NEO 2004 MN4 - Asteriod 99942 Apophis - Impact with Earth

[Ryan Ruck]

Well, if the UN is heading this up we are royally screwed...

Better start getting your bunkers dug now if this is the case!

Maybe they can send "Hans Brix" and he will determine that there really is no asteroid of mass destruction.

[American Patriot]

Well... I posted that because I found it very interesting to say the least. Several astronauts, and scientists are concerned about this enough to have formed an organization to bring attention to it.

They have talked to NASA in the past and now they are discussing it with the UN.

The UN probably because it's ORIGINALY PURPOSE was to bring nations together, for JUST sSUCH A THING.

My bet is that they will stick to non-impact issues like global warming or say things like "We're doomed anyway because of global warming etc" or at worst ignore this as a non-issue.

If they DO put their bodies, minds and SOULS into this, then they may be able to redeam themselves in the eyes of many especially considering exactly just how dangerous this asteroid is

I didn't pick it out of the tens of thousands for the hell of it, but because it was a dangerous thing to begin with.

[American Patriot]

Science & Technology

Mon 19 Feb 2007
Scientists have estimated the asteroid has a one-in-45,000 chance of striking Earth on 13 April, 2036.












It may hit Earth ... but don't worry, we've got a plan

RAYMOND HAINEY


A £150 MILLION space mission should be launched to deflect an asteroid which is set to pass dangerously close to Earth, experts warned yesterday.


The call for action to protect the world from Apophis - named after the Egyptian god of destruction - came from a coalition of astronauts, engineers and scientists with close links to US space agency NASA.

Scientists have estimated the asteroid has a one-in-45,000 chance of striking Earth on 13 April, 2036. Travelling at 28,000mph it could release 80,000 times the energy of the Hiroshima bomb.


The group believes the United Nations should assume responsibility for a space mission - using a vessel called a "gravity tractor" - to knock Apophis off course.


Experts says that the recent approval of a NASA mandate to upgrade its tracking of near-Earth asteroids is expected to uncover hundreds, if not thousands of threatening space rocks in the near future.


Rusty Schweickart, a former astronaut who orbited the moon in the 1969 Apollo 9 mission, said: "It's not just Apophis we're looking at.


"Every country is at risk and we need a set of general principles to deal with this issue."


Mr Schweickart, a member of the Association of Space Explorers, is planning to present an update to the UN Committee on Peaceful Uses of Outer Space this week on plans to develop a global response to an asteroid threat.


Scientists believe that a gravity tractor - a spaceship which flies alongside the asteroid - is the best way to neutralise the threat of Apophis.


A gravity tractor spaceship exerts a slight pull on the targeted mass, slowly pulling it off course and potentially rendering it harmless to life on Earth.


Ed Lu, a veteran of the International Space Station, said that an asteroid the size of Apophis would take nearly a fortnight to deflect away from a collision course with the Earth.


The US is taking asteroid threat seriously, with a massive upgrading of its tracking of near-Earth asteroids.


The Association of Space Explorers, which also includes Russian cosmonauts, is to host a series of workshops this year to refine plans to avoid a potential disaster, then make a formal proposal to the UN in 2009.


Mr Schweickart said that the UN had to adopt a global plan for assessing asteroid threats and deciding when action would need to be taken to avert a massive rock on a collision course with the Earth. He added that launching an asteroid deflection system early to deal with Apophis would not only increase the chances of success, but need far less energy to put the asteroid on a course which will take it far away from Earth.


Typical stony-type asteroids generally burn up on entry to the atmosphere, but asteroids with a large iron content could survive entry and smash into the ground with devastating effect.


But Paul Slovic, president of the US-based Decision Research, which studies judgment, decision-making and risk assessment, said Apophis could destroy a major city or even a entire region.


The most severe asteroid hit in recent times was the Tunguska airburst explosion in Siberia in 1908. The asteroid exploded with the force of a ten-megaton nuclear bomb, flattening huge areas of forest.


Earth had a narrow escape in 1992, when the one to two-mile wide Toutatis asteroid passed within 2.2 million miles of the planet - very close in space terms. And they warned that if Toutatis had hit Earth, it would have had an impact equivalent to between 100 and 150 hydrogen bombs.
The explosion would have blotted out sunlight, caused rocketing global warming and killed off all plant life.


Scientists have calculated that if even if an asteroid misses Earth, if it passes close enough, the planet's gravitational pull could be enough to drag it on to a collision course.


In 2004, NASA issued its highest ever warning on the Torino threat scale for when it gave the MN4 asteroid a rating of four on a scale of one to ten. The previous highest intergalactic threat warning was just one on the Torino scale. However, it failed to strike the Earth.


Astronomers warned then that between now and 2079, there would be at least 38 potentially hazardous encounters with rogue asteroids.


It is thought that dinosaurs were wiped out 65 million years ago after an asteroid hit earth, creating a greenhouse effect which lasted 10,000 years.
It is estimated that asteroids larger than 800 metres wide strike earth about once every 500,000 years.


Major impacts, however, occur around once in a 1,000 years and the chance of dying due to an asteroid impact is estimated to be 20,000/1 - about the same as death from hurricanes, tornadoes, earthquakes and major floods.


Experts say that nuclear missiles could be used to blow up asteroid threats - but the weapons would have to be triggered some distance away to prevent the asteroid breaking up into smaller, but still dangerous, pieces.


Other suggestions - including using kinetic energy devices to pulverise asteroids and using lasers or solar sails to push threats off-course - have all been dismissed as ineffectual or requiring massive investment in new technology.


Related topic

• Space science
  http://news.scotsman.com/topics.cfm?tid=6

This article: http://news.scotsman.com/scitech.cfm?id=264972007
Last updated: 19-Feb-07 00:47 GMT

[Ryan Ruck]

The group believes the United Nations should assume responsibility for a space mission - using a vessel called a "gravity tractor" - to knock Apophis off course.

Awww... That is the least cool way to do it.

I won't be happy until I get to see an asteroid blown to smitherines:

The explosion would have blotted out sunlight, caused rocketing global warming and killed off all plant life.

...

It is thought that dinosaurs were wiped out 65 million years ago after an asteroid hit earth, creating a greenhouse effect which lasted 10,000 years.

Oh, so sorry. Please play again Al Gore.

The exact opposite would be the result. Blotting out sunlight to the surface would result in global cooling!

I swear, they just try so hard to get their agenda in don't they?

[American Patriot]

Oh, so sorry. Please play again Al Gore.

The exact opposite would be the result. Blotting out sunlight to the surface would result in global cooling!

I swear, they just try so hard to get their agenda in don't they?

Yeah... I don't get it. Which was it?

It would be a global cooling effect.

[American Patriot]

99942 Apophis (2004 MN4)

Current assessments: NEODyS [backup] & JPL NEOPO
Diameter: 250 meters (JPL estimate)
JPL: Orbit Viewer NEODyS: object home page [backup] & observations [backup]
Packed designation: 99942 (originally K04M04N)
Circulars: MPECs 2004-Y25, 2004-Y60, 2004-Y63, 2004-Y64, 2004-Y66, 2004-Y68, 2004-Y69, 2004-Y70 & 2004-Y71
[jump to assessment tables]
Notes: 2004 MN4 was discovered on 19 June 2004 by the team of Roy Tucker, David Tholen, and Fabrizio Bernardi, with Roy Tucker at the 90" Bok Telescope at Kitt Peak in Arizona. It was designated 2004 MN4 at the time, but a discovery MPEC was not issued. This object was rediscovered on 18 Dec. by Gordon Garradd at the Siding Spring Survey (SSS) and it received its first MPEC, 2004-Y25, on the 20th.
After the next observations became available, from SSS on the 22nd, both JPL and NEODyS posted 2004 MN4 with the first-ever Torino Scale 2 rating ("merits concern" for "A somewhat close, but not unusual encounter. Collision is very unlikely."). The next day NEODyS and JPL raised their ratings to yet another unprecedented level — TS-4 ("merits concern" for "A close encounter, with 1% or greater chance of a collision capable of causing regional devastation"). From the 24th forward, both risk monitors also had sets of several impact solutions rated at TS-1 (a routine alert for "merits special monitoring").
On 27 Dec. 2004 it was reported in MPEC 2004-Y70 that 2004 MN4 had been found in images from the Spacewatch 0.9m telescope from March 15th, extending this object's observing arc by a very significant 96.060 days.
Very early on 28 Dec. UT, NEODyS eliminated solutions earlier than 2044 and lowered its overall assessment to TS-1. And JPL soon revised its assessment also to TS-1. On several occasions since going to TS-1, JPL or NEODyS have put out assessments that went to TS-0 (not shown in the compiled risk tables) but were later corrected to TS-1.
2004 MN4 was observed by radar from Arecibo in Puerto Rico on 27, 29, and 30 Jan. and 7 Aug. 2005.
2004 MN4 was numbered 99942 2004 MN4 on 24 June 2005 and 99942 2004 MN4 on 19 July 2005 was named 99942 Apophis after the Greek name for the ancient Egyptian's Apep, god or demon of darkness, chaos, and destruction.
JPL on 5 Aug. 2006 (still the 4th in Pasadena) lowered its 99942 Apophis risk assessment Torino Scale rating to TS-0 ("likelihood of collision is zero, or so low as to be effectively zero"). NEODyS lowered its rating to TS-0 on Sept. 1st.
About astrometry, the Spaceguard Central Node's observing campaign's first page dated April 21st says, "Optical observations not very useful before the apparition in 2013." It was observed again by radar from Arecibo on 6 May 2006, which was reflected in risk assessment updates on May 18th.
Resources (newest first)

• JPL statement, "Radar Observations Refine the Future Motion of Asteroid 2004 MN4," 3 Feb. 2005
• NEODyS statement, "Near-Earth Asteroid 2004 MN4: current status," 2 Feb. 2005
• JPL statement, "Possibility of an Earth Impact in 2029 Ruled Out for Asteroid 2004 MN4," 27 Dec. 2004
• JPL statement, "Near-Earth Asteroid 2004 MN4 Reaches Highest Score To Date On Hazard Scale," issued 23 Dec., updated on the 24th
• Roy Tucker's 1 July 2004 article, "A sweet position," about the observing run in which 2004 MN4 was first discovered, although not mentioned in the article

News coverage (newest first)

• "Asteroid 2004 MN4: A Really Near Miss!" Sky & Tel. 4 Feb. 2005 article
• "Closest Flyby of Large Asteroid to be Naked-Eye Visible," Space.com 4 Feb. 2005 article
• "Asteroid Earth impact in 2029 ruled out," AP story at CNN 29 Dec. 2004
• "Earth Safe from Asteroid 2004 MN4," Sky & Tel. 28 Dec. 2004
• "2004 MN4: swing and a miss," Astronomy.com 27 Dec., updated 28 Dec. 2004
• "Whew! Asteroid Won't Hit Earth in 2029, Scientists Now Say," Space.com 27 Dec. 2004
• "Asteroid Watch: Odds of 2029 Collision Stuck at 1-in-40," Space.com 27 Dec. 2004
• "Worrisome Asteroid Underscores Planetary Defense Mission," Space.com 27 Dec. 2004
• "Asteroid Has Outside Chance of Hitting Earth in 2029," Space.com 24 Dec. 2004
• "Asteroid gets elevated risk rating, but impact unlikely," AP story at Arizona Central 23 Dec. 2004

[ CRT news | 2004 MN4 top | page top ]

NEODyS Clomon Assessment		JPL NEOPO Sentry Assessment
Years VI PS Cum PS Max T S Arc Days 2036-2076 7 -2.56 -2.57 0 884.519	21 Oct. 06
	20 Oct. 06	Years VI PS Cum PS Max T S Arc Days Prob Cum Diam 2036-2037 2 -2.52 -2.52 0 884.519 2.2e-05 0.250
See the 2004 A/CC CRT Object Archive for the VI history of 99942 Apophis (2004 MN4)

[American Patriot]

Did these calculations on Anomalies some months back, almost two years now I reckon. Anyway, here's the full text of one of the messages there.

quote:

---

That rock would certainly flatten a fair-sized city but not too much else. The one that may have killed the dinosaurs was around 6 miles in diameter. And I read somewhere that one half that size could still create an extinction level event. Not sure though.

---

Well, lemme see here. We can estimate with some accuracy what would happen if a rock this size hit us, given some information, and assuming a bit more. Of course any assumptions we make might be in error, but this will give us a rough guess at what will probably happen upon impact.

With that, let's work out some details.

That rock is about 1/4 mile across. That's 5280*.25=1320 feet, which is 440 meters in diamter.

The minimum impact an object can have is about 11 Km/s. The maximum is about 72 Km/s.

Let's pick something in the middle since I don't know the actual parameters at this point. Say... 45 Km/s.

We have an object which is probably dense rock, density would be about 3000 kg/m^3.

Most probable impact angle would be about 47 degrees. (It will be between 45 and 90, 90 being from straight up.)

Most probable impact location will be ocean. The world is composed of about 2/3s water. So, we're gonna have a water impact. An ocean. Say, the Atlantic, but close to a shore line (we have to see the effects you know). The average depth of the atlantic is about 3900 meters.

Let's set a distance from impact at 100 km. So 100 Km off the coast of California.

Ok, we have some working data now.

Using a calculator program provided by Robert Marcus, H. Jay Melosh, and Gareth Collins found here: http://www.lpl.arizona.edu/impacteffects/ ,
we come up with the following information.

Impact Effects
Robert Marcus, H. Jay Melosh, and Gareth Collins

Your Inputs:
Distance from Impact: 100.00 km = 62.10 miles
Projectile Diameter: 440.00 m = 1443.20 ft = 0.27 miles
Projectile Density: 3000 kg/m3
Impact Velocity: 45.00 km/s = 27.95 miles/s
Impact Angle: 45 degrees
Target Density: 1000 kg/m^3
Target Type: Ice/Water

Energy:
Energy before atmospheric entry: 1.35 x 10^20 Joules = 3.24 x 10^4 MegaTons TNT
The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 3.3 x 10^5years

Atmospheric Entry:
The projectile begins to breakup at an altitude of 69600 meters = 228000 ft
The projectile reaches the ground in a broken condition. The mass of projectile strikes the surface at velocity 42 km/s = 26.1 miles/s
The impact energy is 1.18 x 10^20 Joules = 2.82 x 10^4MegaTons.
The broken projectile fragments strike the ground in an ellipse of dimension 1.31 km by 0.927 km

Major Global Changes:
The Earth is not strongly disturbed by the impact and loses negligible mass.
The impact does not make a noticeable change in the Earth's rotation period or the tilt of its axis.
The impact does not shift the Earth's orbit noticeably.

Crater Dimensions:
What does this mean? (http://www.lpl.arizona.edu/~marcus/c...xp.html#crater)

Crater shape is normal in spite of atmospheric crushing; fragments are not significantly dispersed.

Transient Crater Diameter: 11.3 km = 7 miles
Transient Crater Depth: 3.98 km = 2.47 miles

Final Crater Diameter: 15.5 km = 9.64 miles
Final Crater Depth: 0.676 km = 0.42 miles

The crater formed is a complex crater.
The volume of the target melted or vaporized is 0.742 km3 = 0.178 miles3
Roughly half the melt remains in the crater , where its average thickness is 7.44 meters = 24.4 feet

Thermal Radiation:
What does this mean?

Time for maximum radiation: 0.234 seconds after impact

Visible fireball radius: 9.02 km = 5.6 miles
The fireball appears 20.5 times larger than the sun
Thermal Exposure: 5.06 x 105 Joules/m2
Duration of Irradiation: 12.7 seconds
Radiant flux (relative to the sun): 39.7

Seismic Effects:
What does this mean?

The major seismic shaking will arrive at approximately 20 seconds.
Richter Scale Magnitude: 7.6
Mercalli Scale Intensity at a distance of 100 km:

VI. Felt by all, many frightened. Some heavy furniture moved; a few instances of fallen plaster. Damage slight.

VII. Damage negligible in buildings of good design and construction; slight to moderate in well-built ordinary structures; considerable damage in poorly built or badly designed structures; some chimneys broken.

Ejecta:
What does this mean?

The ejecta will arrive approximately 144 seconds after the impact.
Average Ejecta Thickness: 14.4 cm = 5.66 inches
Mean Fragment Diameter: 9.93 cm = 3.91 inches

Air Blast:
What does this mean?

The air blast will arrive at approximately 303 seconds.
Peak Overpressure: 58700 Pa = 0.587 bars = 8.34 psi
Max wind velocity: 113 m/s = 253 mph
Sound Intensity: 95 dB (May cause ear pain)
Damage Description:

Multistory wall-bearing buildings will collapse.

Wood frame buildings will almost completely collapse.

Glass windows will shatter.

Up to 90 percent of trees blown down; remainder stripped of branches and leaves.

Tell me more...http://www.lpl.arizona.edu/~marcus/effects.pdf

Click here for a pdf document that details the observations, assumptions, and equations upon which this program is based. It describes our approach to quantifying the important impact processes that might affect the people, buildings, and landscape in the vicinity of an impact event and discusses the uncertainty in our predictions. The processes included are: atmospheric entry, impact crater formation, fireball expansion and thermal radiation, ejecta deposition, seismic shaking, and the propagation of the atmospheric blast wave.

My conclusion? It won't destroy life as we know it, but it sure won't be very pretty.

[American Patriot]

Some more copy-over's follow, so that we can follow the science on this

quote:

---

Hitting the ocean at 100Km out should create a tsunami too shouldn't it?

---

Oh yeah. That program doesn't really take that into account exactly. It gives an approximation of what will happen. But, yes. An ocean hit will be even more devastating that would a solid ground hit. The amount of ejecta from such a hit would include water vapor, as steam and vaporized water from the explosion.

The results would include, but not be limited to, tidal waves hitting coast lines in all directions radiating out from the impact zone, and massive amounts of water being thrust into the atmosphere, and even perhaps into space if the rock is big enough.

A few months back, I went to visit Meteor Crater, Arizona. It is something I've wanted to do since I was a six year old and first saw pictures of the crater in astronomy books. Well, let's just say it was "impressive".

That rock was only 300 feet across, and was an iron core meteorite. I touched a piece of it in the museum there, which they estimate weighs about 1100 pounds. It was only about 18 inches long, and perhaps 10 inches in diameter. The fella there said we could "take it home if we could carry it out". I did try to lift it and barely could move it. It was very, very heavy.

The crater that meteor made was over 300 feet deep, and almost exactly one mile across. The distance around the rim is just over 3 miles (diameter * Pi). That meteor was much more dense than our example above too. So supposing that rock is made of iron instead of rock, you can figure it out for yourselves with the calculator. You can also see that if you increase the speed that amount of energy goes up by several magnatudes as well. That's an example of kinetic energy, my friends.

Also, you must realize something else. Depending on how the rock approached the planet can mean a relative change in speed. If it approches the Earth from the "front", that is in front of the orbit, the relative speed increases. The Earth travels at about 29.77 Km/S in orbit around the sun. Anything approaching the Earth in front of this orbit with add to that speed.

Anything approaching us from BEHIND the orbit would subtract this speed differential. So, if we assume some averge, standard speed for our objects impacting, we can use those as a kind of bench marking test.

quote:

---

So basically it would be equal to a large nuclear explosion off the coast of CA.? I guess its kinda moot though since scientists have already decided that it will certainly miss according to the latest news on it.
But its still interesting to see what we could expect.

---

I know they say the chances are low. Who knows though? There are a lot of other factors out there which will determine it's path. Other gravitational fields for instance. Just because it isn't going to hit us next Thursday or in 2028, doesn't mean that another pass beyond Mars won't slow it or speed it a bit more and place it more on a collison path.

There is a chance that ANYTHING that crosses our planetary path will certainly HIT us one day. The chances are very slim really, but, there is still that CHANCE.

[American Patriot]

Earth safe from asteroid

PASADENA, California: Additional observations have ruled out the chance that a recently discovered asteroid, believed to be about 1,300 feet long, could hit Earth in 2029, Nasa scientists said. Last week, asteroid 2004 MN4 had been given a small chance of impacting Earth, based on observations in June and again this month.

Astronomers then began independent efforts to find earlier observations of the asteroid. The Spacewatch Observatory near Tucson, Arizona, with the help of faint pictures of the asteroid in archival images dating to March 15 said, "an Earth impact on April 13, 2029 can now be ruled out."
http://www.gulf-daily-news.com/Story...&IssueID=27285

=================
http://www.mercurynews.com/mld/mercuryne...10516771.htm?1c
Posted on Tue, Dec. 28, 2004

New observations rule out asteroid Earth impact in 2029

Associated Press

PASADENA, Calif. - Additional observations of asteroid 2004 MN4 have ruled out the possibility it could hit Earth in 2029, NASA scientists said.

Based on observations in June and again this month, the big asteroid last week was given a small chance of impacting Earth on April 13 of that year, although the Near Earth Object Program Office at Jet Propulsion Laboratory said it was likely that a collision would be ruled out as more information was learned about its orbit.

Astronomers then began independent efforts to find earlier observations of the asteroid.

Jeff Larsen and Anne Descour of the Spacewatch Observatory near Tucson, Ariz., found faint pictures of the asteroid in archival images dating to March 15, the NEO office said in a statement posted on its Web site this week.

"These observations extended the observed time interval for this asteroid by three months allowing an improvement in its orbit so that an Earth impact on 13 April 2029 can now be ruled out," the NEO office said.

The refined trajectory of the object also ruled out an impact with the moon.

The NEO office noted that the exact position that the asteroid will be in on April 13, 2029, is still not known, but neither the projected position nor possible alternate positions touch Earth.

The pass by Earth will alter the asteroid's path and create some uncertainty about its subsequent trajectory, but the NEO said its analysis of 2004 MN4 indicated that no further encounters in the 21st century were of any concern.

Spacewatch is a group at the University of Arizona's Lunar and Planetary Observatory.

ON THE NET

Near Earth Object Office: http://neo.jpl.nasa.gov/

Spacewatch: http://spacewatch.lpl.arizona.edu/
=================

Worrisome Asteroid Underscores Planetary Defense Mission
By Leonard David
Senior Space Writer
posted: 27 December 2004
08:19 am ET

BOULDER, Colo. -- A cautionary yellow-flag has been raised on a Near-Earth Asteroid (NEA) that is calculated to pass near the Earth in April 2029. The flyby distance is uncertain and an Earth impact cannot yet be ruled out.

The object’s brightness suggests that it measures over 1,300 feet (400-meters) in diameter. If indeed the asteroid -- tagged as 2004 MN4 -- does have Earth’s name on it, this errant space rock, given its apparent size, is capable of causing regional devastation.

While the asteroid is likely to be demoted from its current threat level, the case of 2004 MN4 comes at a time when NASA is weighing the prospect of flying a future asteroid mission that could evaluate planetary defense techniques.

Trajectory modification

Last month, a study team sponsored by the Jet Propulsion Laboratory (JPL) culled together a list of Prometheus-class, fission-powered space missions for early next decade. Prometheus is NASA’s nuclear electric propulsion effort.

Within a list of six potential candidate efforts identified for detailed study is a near-Earth object (NEO) asteroid mission.

According to the JPL study obtained by SPACE.com, that mission would visit several NEOs, the first within three years of launch.

The idea is to rendezvous with and carry out orbiting science at each object. An "extended objective" suggested in the study might be to attempt a landing to assess technologies for surface operation and nudging the object in a test of trajectory modification.

Planetary protection: demonstration flight

Since its creation in 2002, the non-profit B612 Foundation has campaigned for the perfection of asteroid deflection skills.

Former NASA astronaut, Russell Schweickart, is Chairman of the B612 Foundation. The goal of the group of scientists, technologists, astronomers, astronauts, and other specialists is to significantly alter the orbit of an asteroid in a controlled manner by 2015.

A candidate for a Prometheus 1 mission, Schweickart told SPACE.com, is a demonstration trek to an asteroid. It would gather critical engineering design information for a planetary protection system. That "D1" flight would dovetail into a D2, dress rehearsal deflection mission, to further refine and ready full-up, Earth-protecting techniques and technologies.

Schweickart notes from the start that, while the probability of a highly destructive asteroid impact on Earth in the immediate future is slight, the consequence of such an occurrence is extreme, and mitigation efforts should begin now.

In regards to the new observations of asteroid 2004 MN4, Schweickart added, the most likely scenario is that this object will disappear from concern in the next few days and/or weeks.

How high is high enough?

But Schweickart does see asteroid 2004 MN4 as a ringing warning bell.

"It is worth realizing that it is only happenstance that the 2004 MN4 impact date is in April 2029. It could just as well have been 2019...or 2009…or any other date," Schweickart said. "Even with the current 2029 date, the calendar suggests that we should be acting now."

Schweickart said that one wants to arrive at an asteroid to be deflected roughly 10 years
ahead of impact, meaning 2019 in this case. The Prometheus program schedule would barely support this, he said, although it would undoubtedly be compressed if a 2004 MN4 potential impact were to remain a high probability.

But how high is high enough, Schweickart questioned: 1-in-50? 1-in-100? 1-in-20?

"How could we design such a mission unless we knew more about the surface structural characteristics? Our B612 mission seems to have passed most of the NASA ‘sniff’ tests, but we still need to understand the structural characteristics of the surface to design the attachment mechanism for the ‘tugboat’. This is one of the key objectives of our proposed D1 mission," Schweickart stated.

2004 MN4: a wake-up call

Schweickart advised that if a go-ahead was given to begin a deflection maneuver in 2019 to avoid a 2029 impact, he believes that need-to-know design requirements for an asteroid attachment mechanism must be in hand within a 2012-2014 time period.

"That means that we should be planning, as we have said, a mission to an asteroid -- and in this case probably 2004 MN4 itself – now. It would not necessarily have to be a Prometheus type mission. It could be done using conventional means," Schweickart said.

Whatever the case, there is definite need to begin building the necessary knowledge base -- such as understanding the surface properties of NEOs -- "as soon as possible," Schweickart emphasized. "Asteroid 2004 MN4 is indeed a wake-up call!"

Poke, prod and push

Dan Durda, a space scientist at Southwest Research Institute here, is President of the B612 Foundation. He also highlighted the need to know more about asteroids before hustling out on a deflection mission.

"The reason for a mission to go out, poke, prod and push on an actual near Earth asteroid is precisely because there is still so much we don't yet understand about the structure of these objects," Durda told SPACE.com.

The operational objective and exploration goal of a B612/Prometheus demonstration (D-1) mission, Durda said, "is to learn by doing."

Durda said becoming skilled at how to deploy and operate a power-rich and highly efficient spacecraft system will extend space exploration capabilities. Given that competence, more can be learned regarding the surface properties and internal structure of objects. That data is not only useful for utilizing them for their valuable resources, but also to cancel out an object that is threatening to Earth and our species, he said.

"There's only so much we can learn about near Earth asteroids by studying them from afar," Durda said. "At some point you have to get on the ‘ground’ and get your hands dirty. I hope for that to be literally true someday very soon!"

Key questions

Durda said that computer simulations can only take you so far.

There are several key questions about asteroids in Durda’s mind: How hard can you push on a pile of rubble held together by its own gravity before its internal components begin to shift around?

Furthermore, how much fine debris might cling to an asteroid’s meteoroid-blasted surface? And how might that material mess up the works on your spacecraft if electrostatics makes it stick and creep into every nook and cranny?

"The things that work well and the things that don't work at all on a mission like this will all teach us a great deal about the real world of working on and about the surface of a near Earth asteroid…be it for mining or planetary protection," Durda advised.

Unexpectedly high value

"Every one of these NEA events is different, and often in unexpected ways," noted Clark Chapman, an asteroid expert also at Southwest Research Institute, and a founding member of the B612 group. "Of course, the big thing that is different about this case is the totally unexpectedly high value of 2004 MN4 on the Torino Scale, he explained.

The Torino Scale is used by scientists to categorize the threat of asteroids. The scale uses numbers and colors to indicate risk of collision, all based on complicated analysis of an asteroid's path and calculations of how that path might change as it’s affected by gravity from Earth and other bodies.

The asteroid has been at four on the Torino Scale since last Friday, and the latest observations have actually increased the odds of impact from 1-in-60 to roughly 1-in-40, Chapman said. "I hadn't expected to see such a high probability of impact -- recognizing that there are still 39 chances in 40 that it won’t impact -- by such a large object in my lifetime," he said.

Most newsworthy

The other thing that is different about 2004 MN4, Chapman said, is that its discovery was anomalous. Instead of being discovered by any of the major search telescopes, this finding was made using instrumentation that was new and not fully understood. "So it wasn't until a much later, independent discovery was made that the original data could be linked to the more recent data," he said.

Asteroid 2004 MN4 is "the most newsworthy NEA event that has happened since the NEA threat was recognized," Chapman observed.

"I'm not saying that there should be more news coverage than has been given. In all likelihood, in the next few days or weeks, the impact probability will retreat toward zero, and there's no particular reason to alarm people. After all, the potential threat is a quarter-century away. But given the treatment of NEAs in the past, I'm still surprised that a 1-in-40 chance of a country-destroying impact hasn't been noticed by the media," Chapman said.

[American Patriot]

From Jan 2005:

Observations rule out asteroid impact

Associated Press
http://www.globetechnology.com/servl...ry/Technology/

PASADENA, Calif. —


Associated Press
— Additional observations have ruled out the chance that a recently discovered asteroid, believed to be about 1,300 feet long, could hit Earth in 2029, NASA scientists said.
Last week, asteroid 2004 MN4 had been given a small chance of hitting Earth, based on observations in June and again this month. Astronomers then began independent efforts to find earlier observations of the asteroid.
The Spacewatch Observatory near Tucson, Ariz., found faint pictures of the asteroid in archival images dating to March 15, the Near Earth Object Program Office, located at the Jet Propulsion Laboratory, said in a statement on its website this week.
The pictures from March allowed scientists to refine the asteroid's projected trajectory, and "an Earth impact on 13 April 2029 can now be ruled out," the program office said.
Scientists also ruled out an impact with the moon.
Spacewatch is associated with the University of Arizona's Lunar and Planetary Observatory.

[American Patriot]

And this one I disagree with, but post anyway:

Nasa gaffe that rocked the globe

RICHARD GRAY

http://scotlandonsunday.scotsman.com...fm?id=25242005


IT WILL go down as the most extreme example of crying wolf in the history of mankind.

Scientists who terrified the life out of millions of people over Christmas by issuing an asteroid strike red alert have now admitted they got their sums wrong.

While most people prepared for the seasonal festivities, teams from the US and Italy were nervously studying a 440-yard-long chunk of rock in space called 2004 NM4.

After carrying out calculations, and two days before Christmas, the scientists announced to the world that in 2029 there was a one in 37 chance of a hit. Those odds and size of the asteroid made it the biggest threat to the planet ever recorded.

Panicked sky-watchers across the globe debated what could be done in the next 24 years to avert a collision, an event that could wipe out millions of people.

But after carrying out further calculations, the scientists realised they had bungled: the asteroid would sail past Earth at the relatively comfortable distance of 37,000 miles and mankind was safe - for now.

The asteroid was first spotted in June last year before being rediscovered shortly before Christmas, allowing astronomers to calculate its course across the solar system.

Initially, the teams at Nasa’s Jet Propulsion Laboratory and the University of Pisa estimated it had just a 1 in 300 chance of hitting the Earth on Friday, April 13, 2029 but subsequent calculations dramatically narrowed the likelihood of impact.

The risk posed by asteroids to Earth are calculated using a measurement known as the Terino Impact Hazard Scale, which plots the probability of an object hitting the Earth against the energy it will have on impact.

Before Christmas, astronomers had never spotted an asteroid with a Terino number greater than 2, but 2004 NM4 was found to have a Terino risk of 4.

"In terms of the damage this would do, it would cause significant regional devastation," said Kevin Yates from the Near Earth Object Information Centre in Leicester.

"This certainly got everybody quite excited. It was the highest ever probability we have ever had, so there were a lot of people staying in touch over the festive period to see what was happening."

Slamming into the Earth at an estimated 6,000mph, the initial blast from the strike would destroy everything in the immediate area while the shock wave would cause widespread death and destruction for miles. The material ejected from the blast site would enter the Earth’s atmosphere, causing global cooling and unleashing further disaster.

A week after Nasa’s original announcement on December 23, its astronomers around the world were frantically searching for extra data.

Jeff Larson, of the Spacewatch Observatory at the University of Arizona, found the project’s telescopes had spotted the asteroid back in March but it had gone unnoticed.

With the extra data on the asteroid’s orbit around the sun these sightings provided, Nasa was then able to work out 2004 NM4 would slip harmlessly past between the Earth and the Moon.

Scottish meteorite expert Rob Elliot said the US space agency risked crying wolf.

He said: "Nasa has a habit of announcing objects are going to hit the Earth with frightening regularity.

"They hype up a sighting on very little data before carrying out more calculations which diminish the risk.

"Unfortunately some people take these scares to heart and many people are sick and tired of it.

"There is a certain amount of resentment from the meteorite community that they keep doing this. They should only really release a statement if it warrants it."

But Donald Yeoman, manager of Nasa’s JPL, said: "We have to decide if we do these calculations in private whether to release the data when it is definite or put everything out there in real time. We choose to take the latter option as it is in line with our policy of keeping the public informed.

"On this occasion the object got a much higher risk rating than anything else we have seen in tens of years of doing this. Our subsequent computations gave us possible locations of NM4 in 2029 which did not involve either the Earth or the Moon, ruling out a strike."

John Davies, an astronomer at the Royal Observatory Edinburgh, backed Nasa. He said: "It is a difficult situation for astronomers to know when to say something.

"If they say something too early then they can be accused of crying wolf and if they wait too long then people ask if they have been asleep.

"With something that is not predicted to impact for 25 or 50 years though, waiting a week for further calculations is not going to make much difference.

"One thing this high Terino scale rating has done is to focus our attention on making sure the right procedures are in place on how to respond should another one come along."

The asteroid’s estimated size has been worked out from its brightness, which assumes its reflectivity is similar to that of other asteroids that have been observed.

The closest known near miss in recent times happened last March when a 10-yard asteroid came within 4,000 miles of the planet. The same month, an asteroid 33 yards across missed the planet by 16,780 miles.

[American Patriot]

This one explains why I am concerned about this asteroid.

Earth’s gravity may lure deadly asteroid
The Times (UK) ^ | April 18, 2005 | By Nigel Hawkes

A HUGE asteroid which is on a course to miss the Earth by a whisker in 2029 could go round its orbit again and score a direct hit a few years later.

Astronomers have calculated that the 1,000ft-wide asteroid called 2004 MN4 will pass by the Earth at a distance of between 15,000 and 25,000 miles — about a tenth of the distance between the Earth and the Moon and close enough to be seen with the naked eye.

Although they are sure that it will miss us, they are worried about the disturbance that such a close pass will give to the asteroid’s orbit. It might put 2004 MN4 on course for a collision in 2034 or a year or two later: the unpredictability of its behaviour means that the danger might not become apparent until it is too late.

As a safety precaution, some experts are calling for 2004 MN4 to be “tagged” with a transponder that would constantly radio its position. Scientists hope that this would provide enough warning to allow emergency action if necessary, possibly by diverting the object away from the Earth. Other instruments on the probe could provide information about its composition.

Benny Peiser, from Liverpool John Moores University, who is an expert on asteroid hazards, said: “We don’t know what that asteroid is made of and that might influence the way it’s affected by the Earth’s gravitational pull. There are other close approaches, in 2034 and 2035. In all likelihood it will produce an orbit that will not intercept the Earth, but we don’t know.”

The asteroid is big enough to cause damage on a regional scale, with an expected impact equivalent to a 1,000-megatonne explosion. It was discovered last June and its orbit plotted in detail by December. Startled astronomers calculated at one point that its chances of a direct hit on Friday, April 13, 2029, were 1 in 38. But additional calculations have set those fears to rest. The asteroid is now expected to miss but come close enough to be below the altitude of TV satellites. It should be visible as a rapidly moving point of light.

Brian Marsden, of the Harvard-Smithsonian Centre for Astrophysics in Cambridge, Massachusetts, expects the close encounter to increase the frequency of the asteroid’s orbit, creating the possibility of further close encounters every five to nine years.

An interceptor mission is feasible and Dr Peiser said that an opportunity would arise in 2012, when 2004 MN4 will be ten million miles from Earth. “That’s not a big distance as far as space missions go,” he said.

“This is most likely not the object with our number on it, but one day we will have to address this question and we’ll need the technology. A transponder mission should not be too complicated or costly, and would provide a lot of vital data.”

Copyright 2005 Times Newspapers Ltd.

[American Patriot]

Asteroid will get two shots at Earth
Nigel Hawkes, London
April 19, 2005

http://www.theaustralian.news.com.au...5E2703,00.html

A GIGANTIC asteroid that is on a course to miss the Earth by a whisker in 2029 could go around its orbit again and score a direct hit a few years later.

Astronomers have calculated that the 350m-wide asteroid called 2004 MN4 will pass by Earth at a distance of between 24,140km and 40,235km - about one-tenth of the distance between the Earth and the moon and close enough to be seen with the naked eye.

Though they are sure it will miss us, the astronomers are worried about the disturbance such a close pass will give to the asteroid's orbit. It might put 2004 MN4 on course for a collision in 2034 or a year or two later.

The unpredictability of its behaviour means the danger might not become apparent until it is too late.

As a safety precaution, some experts are calling for 2004 MN4 to be "tagged" with a transponder that would constantly radio its position.

Scientists hope this would provide enough warning to allow emergency action if it is necessary, possibly by diverting the asteroid away from Earth. Other instruments on the probe could provide information about its composition.

Benny Peiser, of Liverpool John Moores University, who is an expert on asteroid hazards, said: "We don't know what that asteroid is made of, and that might influence the way it's affected by the Earth's gravitational pull. There are other close approaches, in 2034 and 2035. In all likelihood it will produce an orbit that will not intercept the Earth, but we don't know."

The asteroid is big enough to cause damage on a regional scale, with an expected impact equivalent to a 1000megatonne explosion. It was discovered last June and its orbit was plotted in detail by December.

Startled astronomers calculated at one point that its chances of a direct hit on Friday, April 13, 2029, were one in 38. But additional calculations have set those fears to rest.

The asteroid is now expected to miss but come close enough to be below the altitude of TV satellites. It should be visible as a rapidly moving point of light.

Brian Marsden, of the Harvard-Smithsonian Centre for Astrophysics in Cambridge, Massachusetts, expects the close encounter to increase the frequency of the asteroid's orbit, creating the possibility of further close encounters every five to nine years. An interceptor mission is feasible and Dr Peiser said that an opportunity would arise in 2012, when 2004 MN4 would be 16million kilometres from Earth.

"That's not a big distance as far as space missions go," he said.

"This is most likely not the object with our number on it, but one day we will have to address this question and we'll need the technology."

The Times

[American Patriot]

Oct 2005:

Once again, this Asteroid is showing up in the news.

Folks... I keep telling you, this is the one to watch.

Rick

http://www.mosnews.com/news/2005/10/03/asteroid.shtml



Photo from http://www.narod.ru
Asteroid Impact May Wipe out Life on Earth in 2035 — Russian Scientists

Created: 03.10.2005 16:38 MSK (GMT +3), Updated: 16:38 MSK, 37 minutes ago

MosNews

A scientific conference dedicated to asteroid and comet security opened in the Practical Astronomy Institute in St. Petersburg on Monday, Russian news agencies report. One of its participants said that the 2004 MN4 asteroid could hit Earth in 2035, wiping out all life on the planet.

One of the scientists taking part in the conference, Viktor Shor of the Practical Astronomy Institute of the Russian Academy of Sciences, said that at present many experts see a real threat of Earth’s collision with the 2004 MN 4 asteroid. Initially the collision was predicted for 2028, but the latest calculations show that in 2028 the asteroid will only pass very close to Earth. However, Shor says that his research predicts that the asteroid’s orbit could change and it may return in seven years this time crashing into the Earth’s surface.

Experts from the Russian Institute of Calculus Mathematics and Mathematical Physics also presented models of space-originated and landslide tsunamis. “A powerful asteroid impact on the ocean could cause tsunamis several hundred meters high,” the scientists said, adding that regular tsunamis caused by earthquakes rarely reach 50 meters high.

According to the model, the impact of a 500-meter asteroid traveling at a speed of 10-20 kilometers per second hitting the ocean would cause a circular wave 200-meters high. An asteroid 10 kilometers in diameter would cause a tsunami 4 kilometers high which would be about 400 meters high as it hit land. The scientists say that a similar disaster took place millions of years ago and resulted in the extinction of 90 percent of all living species.

[American Patriot]

The sky is falling, really
Russell L. Schweickart
Published: March 16, 2007

TIBURON, California: People have been aware for some time now that there is a slim but real possibility — about 1 in 45,000 — that an 850-foot-long asteroid called Apophis could strike Earth with catastrophic consequences on April 13, 2036. What few probably realize is that there are thousands of other space objects that could hit us in the next century that could cause severe damage, if not total destruction.

Last week two events in Washington — a conference on "planetary defense" held by the American Institute of Aeronautics and Astronautics, and the release by NASA of a report titled "Near-Earth Object Survey and Deflection Analysis of Alternatives" — gave us good news and bad on this front. On the promising side, scientists have a good grasp of the risks of a cosmic fender-bender, and have several ideas that could potentially stave off disaster. Unfortunately, the government doesn't seem to have any plan to put this expertise into action.

In 1998, Congress gave NASA's Spaceguard Survey program a mandate of "discovering, tracking, cataloging and characterizing" 90 percent of the near-Earth objects larger than one kilometer (3,200 feet) wide by 2008. An object that size would probably destroy civilization.

The consensus at the conference was that the initial survey is doing fairly well although it will probably not quite meet the 2008 goal. Realizing that there are many smaller but still terribly destructive asteroids out there, Congress has modified the Spaceguard goal to identify 90 percent of even smaller objects — 460 feet and larger — by 2020. This revised survey, giving us decades of early warning, will go a long way toward protecting life on the planet in the future.

The good news is that scientists feel we have the technology to intercept and deflect many asteroids headed toward Earth. Basically, if we have early enough warning, a robotic space mission could slightly change the orbit of a dangerous asteroid so that it would subsequently miss the planet.

Two potential deflection techniques appear to work nicely together — first we would deflect the asteroid with kinetic impact from a missile (that is, running into it); then we would use the slight pull of a "gravity tractor" — a satellite that would hover near the asteroid — to fine-tune its new trajectory to our liking. (In the case of an extremely large object, probably one in 100, the missile might have to contain a nuclear warhead.) To be effective, however, such missions would have to be launched 15 or even 30 years before a calculated impact.

The bad news? While this all looks fine on paper, scientists haven't had a chance to try it in practice. And this is where NASA's report was supposed to come in. Congress directed the agency in 2005 to come up with a program, a budget to support it and an array of alternatives for preventing an asteroid impact.

But instead of coming up with a plan and budget to get the job done, the report bluntly stated that "due to current budget constraints, NASA cannot initiate a new program at this time."

Why did the space agency drop the ball? Like all government departments, it fears the dreaded "unfunded mandate." Congress has the habit of directing agencies to do something and then declining to give them the money to do so. In this case, Congress not only directed NASA to provide it with a recommended program but also asked for the estimated budget to support it. It was a left-handed way for the Congress to say to NASA that this is our priority like it or not. But for some reason NASA seems to have opted for a federal form of civil disobedience.

Another problem with the report was that, while it outlined other possibilities, it estimated that using a nuclear missile to divert an asteroid would be "10 to 100 times more effective" than non-nuclear approaches. It is possible that in some cases — such as an asteroid greater than a third of a mile across — the nuclear option might be necessary. But for the overwhelming majority of potential deflection cases, using a nuclear warhead would be like a golfer swinging away with his driver to sink a three- foot putt; the bigger bang is not always better.

Why the concern? First, even with good intentions, launching a nuclear-armed missile would violate the international agreements by which all weaponry is banned from space. Second, the laws of probability say we would be struck by such a large asteroid only once every 200,000 years — that's a long time to keep a standing arsenal of nuclear asteroid-blasters, and raises all sorts of possibilities of accidents or sabotage — the old "cure being worse than the disease" phenomenon.

In the end, this is not just America's problem. The best course is international coordination on deflection technology, along with global agreements on what should be done if a collision looks likely. Along these lines, the Association of Space Explorers, a group of more than 300 people from 30 nations who have flown in space (of which I am a member), is beginning a series of meetings in cooperation with the United Nations to work out the outlines of such an agreement.

Still, as with many global issues, little will be accomplished unless the United States takes the lead. With the entire planet in the cross hairs, NASA can't be allowed to dither. If Congress' mandates and budget requests aren't energizing the agency, perhaps public hearings would shame it into action.

Russell L. Schweickart, a former Apollo astronaut, is the chairman of the B612 Foundation, which promotes efforts to alter the orbits of asteroids.

[American Patriot]

The Sky Is Falling
By Russell L. Schweickart
(The New York Times)



AMERICANS who read the papers or watch Jay Leno have been aware for some time now that there is a slim but real possibility — about 1 in 45,000 — that an 850-foot-long asteroid called Apophis could strike Earth with catastrophic consequences on April 13, 2036. What few probably realize is that there are thousands of other space objects that could hit us in the next century that could cause severe damage, if not total destruction.

Last week two events in Washington — a conference on “planetary defense” held by the American Institute of Aeronautics and Astronautics, and the release by NASA of a report titled “Near-Earth Object Survey and Deflection Analysis of Alternatives” — gave us good news and bad on this front.

On the promising side, scientists have a good grasp of the risks of a cosmic fender-bender, and have several ideas that could potentially stave off disaster. Unfortunately, the government doesn’t seem to have any clear plan to put this expertise into action.

In 1998, Congress gave NASA’s Spaceguard Survey program a mandate of “discovering, tracking, cataloging and characterizing” 90 percent of the near-Earth objects larger than one kilometer (3,200 feet) wide by 2008. An object that size could devastate a small country and would probably destroy civilization.

The consensus at the conference was that the initial survey is doing fairly well although it will probably not quite meet the 2008 goal. Realizing that there are many smaller but still terribly destructive asteroids out there, Congress has modified the Spaceguard goal to identify 90 percent of even smaller objects — 460 feet and larger — by 2020. This revised survey, giving us decades of early warning, will go a long way toward protecting life on the planet in the future.

The good news is that scientists feel we have the technology to intercept and deflect many asteroids headed toward Earth. Basically, if we have early enough warning, a robotic space mission could slightly change the orbit of a dangerous asteroid so that it would subsequently miss the planet.

Two potential deflection techniques appear to work nicely together — first we would deflect the asteroid with kinetic impact from a missile (that is, running into it); then we would use the slight pull of a “gravity tractor” — a satellite that would hover near the asteroid — to fine-tune its new trajectory to our liking. (In the case of an extremely large object, probably one in 100, the missile might have to contain a nuclear warhead.) To be effective, however, such missions would have to be launched 15 or even 30 years before a calculated impact.

The bad news? While this all looks fine on paper, scientists haven’t had a chance to try it in practice. And this is where NASA’s report was supposed to come in. Congress directed the agency in 2005 to come up with a program, a budget to support it and an array of alternatives for preventing an asteroid impact.

But instead of coming up with a plan and budget to get the job done, the report bluntly stated that “due to current budget constraints, NASA cannot initiate a new program at this time.” Representative Bart Gordon, Democrat of Tennessee, was right to say that “NASA’s recommended approach isn’t a credible plan” and that Congress expected “a more responsive approach” within the year.

Why did the space agency drop the ball? Like all government departments, it fears the dreaded “unfunded mandate”; Congress has the habit of directing agencies to do something and then declining to give them the money to do so. This is understandable.

But in this case, Congress not only directed NASA to provide it with a recommended program but also asked for the estimated budget to support it.

It was a left-handed way for the Congress to say to NASA that this is our priority ... like it or not. But for some reason NASA seems to have opted for a federal form of civil disobedience.

Another problem with the report was that, while it outlined other possibilities, it estimated that using a nuclear-armed missile to divert an asteroid would be “10 to 100 times more effective” than non-nuclear approaches. It is possible that in some cases — such as an asteroid greater than a third of a mile across — the nuclear option might be necessary. But for the overwhelming majority of potential deflection cases, using a nuclear warhead would be like a golfer swinging away with his driver to sink a three-foot putt; the bigger bang is not always better.

Why the concern? First, even with good intentions, launching a nuclear-armed missile would violate the international agreements by which all weaponry is banned from space. Second, the laws of probability say we would be struck by such a large asteroid only once every 200,000 years — that’s a long time to keep a standing arsenal of nuclear asteroid-blasters, and raises all sorts of possibilities of accidents or sabotage — the old “cure being worse than the disease” phenomenon.

In the end, of course, this is not just America’s problem, as an asteroid strike would be felt around the globe.

The best course is international coordination on deflection technology, along with global agreements on what should be done if a collision looks likely. Along these lines, the Association of Space Explorers, a group of more than 300 people from 30 nations who have flown in space (of which I am a member), is beginning a series of meetings in cooperation with the United Nations to work out the outlines of such an agreement.

Still, as with many global issues, little will be accomplished unless the United States takes the lead. With the entire planet in the cross hairs, NASA can’t be allowed to dither. If Congress’s mandates and budget requests aren’t energizing the agency, perhaps public hearings would shame it into action.

(Russell L. Schweickart, a former Apollo astronaut, is the chairman of the B612 Foundation, which promotes efforts to alter the orbits of asteroids)

---

Asteroid Apophis to Ram Earth in 2029
What should be done to protect our planet? Specialists consider two options at the moment. One involves demolition of the asteroid, the other one is to push it aside. Pushing the monster aside is less dangerous than an explosion producing thousands of fragments with unpredictable flight patterns. Where will those fragments fly to?
On April 13th, 2029, the asteroid may crush into Earth causing an explosion 100 times bigger than the blast of the A-bomb dropped on Hiroshima in 1945. A large part of Moscow is likely to disappear.

Apophis was discovered by Steve Chesley at NASA in June 2004. He stirred up a lot a buzz among his colleagues by saying that the thing is definitely going to ram into Earth. The colleagues rushed to telescopes and checked the photographs of the celestial sky. They found the asteroid on a photograph taken back in March.

The diameter of MN4 was initially measured at 500 meters. Researchers reduced the diameter to 320 meters after conducting a series of additional calculations. The asteroid rotates once in every 323 days, it crosses Earth's orbit twice a year. There is a real threat of collision, but it is not so deadly as previously thought. The asteroid will not be smashing our planet on April 13th, 2029. But it is expected to cross the sky in a really close vicinity to Earth.

It might as well destroy a communications satellite.

Things may turn for the worse after the near-miss experience. It is not yet clear what will happen after the dangerous rendezvous.

Some astronomers believe the earth's gravitation is capable of diverting the flight path of the asteroid. What direction will it take? Specialists are still busy trying to guesswork the year of a potential disaster: 2035, 2036 or 2037. They release scary estimates saying that the whole Northern Hemisphere may be under threat. The end of the world is out of question though densely populated areas would sustain heavy casualties. An area of 40 square kilometers would lay waste.

What should be done to protect our planet? Specialists consider two options at the moment.

One involves demolition of the asteroid, the other one is to push it aside. Pushing the monster aside is less dangerous than an explosion producing thousands of fragments with unpredictable flight patterns. Where will those fragments fly to?

NASA astronauts Edward Lu and Stanley Love recently came up with an idea ofpushing it aside by using a heavy spaceship. The ship should be heavy enough, from 20 tons to 30 tons.

It would spin around Apophis. The asteroid's trajectory would be deflected by the ship's gravitational effects.

In the meantime, scientists are going to take a closer look at the dangerous heavenly bodies. European Space Agency is planning to launch a spacecraft which is expected to land on asteroids to collect necessary data and images. Astronomers will be able to see the space rocks coming closer to Earth.

(UFO Digest)

[American Patriot]

Techniques like gravity tractors or space tugs might be better ways to deflect asteroids than nuclear blasts—although not necessarily in the eyes of NASA. (credit: B612 Foundation)
The three D’s of planetary defense

by Jeff Foust
Monday, March 19, 2007

To take Hollywood’s word for it, stopping an incoming asteroid or comet from hitting the Earth is fairly straightforward. NASA discovers, or is alerted to the discovery of, an object on an impact course, and quickly cobbles together—either by itself or in cooperation with the Russians—a plan to deflect or outright destroy the intruder with nuclear weapons. Sometimes the job is done by some convenient (if treaty-violating) nuclear weapons already in orbit, but usually it’s a team of astronauts, with some non-professionals with critical skills thrown in, who quickly fly off in a highly modified shuttle to save the day. And save the day they do, although not before some fragments hit the Earth and wreak some havoc. It’s a storyline that has been used and reused a number of times, from Meteor to Deep Impact and Armageddon to, most recently, the pretty awful Sci-Fi Channel film Earthstorm (whose twist is that, this time, the asteroid hits the Moon, and threatens to break it up until our intrepid astronauts—and an explosives expert—save the day.)


Reality, of course, is a bit more complex than what can be compressed into a two-hour movie. Dealing with an object that’s on a collision course is more complicated than sending some astronauts in a nuclear-powered shuttle to blow it up with an atomic bomb: besides the fact that there are no nuclear-powered shuttles that can zip across the solar system, blowing up or even trying to deflect an asteroid with nuclear weapons can cause more harm than good. Movies also tend to gloss over the difficulty in discovering these objects and refining their orbits to confirm that they indeed pose a threat to the Earth: they’re discovered, their orbits plotted, and that’s it. Also overlooked is the decisionmaking process required to determine how best to deal with that impact threat, and who—besides the United States—should be involved in that effort. Those three areas—detection, decisionmaking, and deflection—are critical to successfully dealing with the problem posed by near Earth objects (NEOs), but as recent events have shown, there’s no consensus yet on how it should be done.
Detection

The one facet of planetary defense where there are ongoing official efforts is in the detection of NEOs. For a number of years there have been several efforts underway to search for NEOs, and these efforts have been yielding an increasing bounty of objects thanks to improved techniques and technologies. As a result, about 4,000 NEOs have been discovered to date, according to Don Yeomans, head of the NEO program office at JPL, including some 700 “large” ones with diameters of one kilometer or more.

“The point is that discovery surveys are job one for protecting Earth from asteroid impacts,” said JPL’s Chesley.

Those search efforts have, so far, failed to turn up any objects that have the Earth definitively in its crosshairs. The biggest alarm in recent years came in late 2004, when asteroid 2004 MN4 (since renamed (99942) Apophis) had, based on the orbital information available, about a 2.7-percent probability of colliding with the Earth on April 13, 2029. It failed to make headlines because of the timing (around Christmas and the Asian tsunami that took place soon thereafter); by the time people would have paid attention other observations had reduced the odds of a 2029 impact to zero. (See “Sounding an alarm, cautiously”, The Space Review, May 31, 2005) Still, Apophis does have about a 1-in-45,000 chance of colliding with the Earth in 2036, depending on if it passes through a narrow “keyhole” during its 2029 close approach to the Earth; JPL’s impact risks page lists, as of March 18th, 137 NEOs, including Apophis, that have a non-zero (albeit extremely small) chance of colliding with the Earth at some point in the next 100 years.


That makes the detection and tracking of NEOs critical. “If it’s part of your job to keep the Earth safe from asteroid attacks, there are three important things you always have to remember,” quipped Steve Chesley, a planetary astronomer at JPL, during a press conference at the annual conference of the American Association for the Advancement of Science (AAAS) last month in San Francisco. “First is, you have to find them as early as possible. And the other ones I can never remember. The point is that discovery surveys are job one for protecting Earth from asteroid impacts.”


In a talk during a later session of the AAAS conference, Chesley noted that, in general, impact probabilities will increase as new observations are added, then quickly drop to zero once enough observations are made—assuming that the object is not, in fact, actually on a collision course. Because of that, Chesley said, “you want to delay your efforts [to deflect an asteroid] as long as possible in the hope that the observations move the asteroid off the Earth, in a sense, rather than having to send a spacecraft to do the work.”


While current search systems, like LINEAR in New Mexico and Spaceguard in Arizona, are doing a good job finding large NEOs, they are not as well-suited for detecting the far larger numbers of smaller NEOs believed to exist.


Current estimates suggest that there may be up to 100,000 NEOs 140 meters in diameter or larger, only a tiny fraction of which have been discovered to date. To deal with this issue, Congress, as part of a NASA authorization bill it passed in late 2005, required NASA to perform a study to investigate ways to discover at least 90 percent of these NEOs by 2020.
The study, a summary of which was released by NASA earlier this month, examined a wide variety of ways to do it, from part-time use of existing and planned ground-based telescopes to an array of dedicated telescopes on the ground and in space. By sharing two planned ground-based survey telescopes, the Panoramic Survey Telescope & Rapid Response System (PanSTARRS) and Large Synoptic Survey Telescope (LSST), it would be possible to discover about 83 percent of the potentially hazardous objects 140 meters or larger in diameter by 2020; the 90-percent threshold would be reached in 2026. The 2020 deadline set by Congress could be achieved if those telescopes were augmented with either a dedicated version of the LSST, or a space-based infrared telescope in a Venus-like orbit. In the latter case, this system would find 97 percent of the objects by 2020.


The problem with these enhanced systems, however, is their cost. The NASA study estimated that, in fiscal year 2006 dollars, the system that used the shared telescopes plus a dedicated LSST would cost $835 million through 2020. The system with the shared telescopes and the space-based telescope, not surprisingly, was even more expensive: $1 billion through 2017, the date when it would achieve the 90-percent threshold. That’s big money for a program that currently gets only about $4 million a year for current survey efforts.

If an impact of blast breaks up an asteroid, said Lu, “Essentially what you’re doing is creating orbital debris on a solar system scale… What would be the uproar if we were to break up an asteroid?”

“NASA recommends that the program continue as currently planned, and we will also take advantage of opportunities using potential dual-use telescopes and spacecraft—and partner with other agencies as feasible—to attempt to achieve the legislated goal within 15 years,” the report concluded. “However, due to current budget constraints, NASA cannot initiate a new program at this time.”
Deflection

For many years—dating back at least to the Project Icarus study in the late 1960s (see “Giant bombs on giant rockets: Project Icarus”, The Space Review, July 5, 2004)—the preferred method for dealing with a NEO found to be on an impact course with the Earth was to hit it with one or more nuclear weapons. This was based on the assumption that asteroids were big hunks of rock and/or metal that could be simply pushed by the force of a nuclear blast.


In recent years, however, research into asteroids, including spacecraft missions to or past several asteroids like Eros and Itokawa, have challenged this approach. Small bodies in particular are less likely to be integral chunks of rock than “rubble piles”: agglomerations of smaller objects loosely held together by self-gravity. Attempting to deflect these objects with a nuclear blast could have, in the words of NASA astronaut Ed Lu, “unintended consequences”.


Lu, a member of the board of directors of the B612 Foundation, an organization devoted to the study of asteroid deflection and impact threat mitigation, said at the AAAS conference that nuclear weapons or even a kinetic impact, like that used on NASA’s Deep Impact mission, could break apart a rubble pile asteroid, creating complications in tracking and dealing with all the fragments. “If you do break it up into pieces, what’s your Plan B?” said Lu, who likened such a fragmentation to the orbital debris created by a Chinese ASAT test in January and the controversy that followed. “Essentially what you’re doing is creating orbital debris on a solar system scale… What would be the uproar if we were to break up an asteroid?”


“If you have a way of doing a controlled deflection, you should do that first,” Lu said. And Lu and fellow astronaut Stanley Love have come up with an alternative: the “gravity tractor”. The gravity tractor would be a spacecraft that positions itself near a threatening asteroid, and maintains its position using ion thrusters. The hovering spacecraft imparts a feeble but steady gravitational force that tugs at the asteroid, gradually changing its trajectory.


While the gravity tractor would only make a minor change in the asteroid’s orbit, it would be useful for cases like Apophis where only a slight change is needed to prevent a collision, and other cases where there is plenty of warning. Moreover, since the gravity tractor never makes physical contact with the asteroid, there is no need to be concerned about the asteroid’s composition, structure, spin rate, or other factors that pose hazards to an explosion or impact approach. Nor, Lu added, would it require new technology, since ion engines have already been used on a number of spacecraft, such as Deep Space 1.


Interestingly, though, the recently-released NASA report summary isn’t as generous in praise of the gravity tractor or other so-called “slow push” approaches, such as a tug physically attached to the asteroid or a mass driver that propels small pieces of the asteroid away from the main body. “‘Slow push’ mitigation techniques are the most expensive, have the lowest level of technical readiness, and their ability to both travel to and divert a threatening NEO would be limited unless mission durations of many years to decades are possible,” the NASA report concluded.


The report instead fell back on the old approach of nuclear weapons, but with a slight modification: instead of exploding them on or underneath the surface of the asteroid, they would be detonated at some distance above the surface. “While detonation of a nuclear device on or below the surface of a threatening object was found to be 10-100 times more efficient than detonating a nuclear device above the surface, the standoff detonation would be less likely to fragment the target,” the report concluded. “A nuclear standoff mission could be designed knowing only the orbit and approximate mass of the threat, and missions could be carried out incrementally to reach the required amount of deflection.”
Decisionmaking

Between detection and deflection, though, lies an oft-forgotten step: deciding the course of action to be taken to mitigate the threat posed by the NEO. Who should be responsible for making a decision whose effects impact—figuratively and potentially literally—people around the world?

Apophis has been, said Schweickart, “a terrific learning experience for all of us, because it has tickled every possibility that there is in this business.”

Rusty Schweickart, the Apollo-era astronaut who serves as chairman of the board of the B612 Foundation as well as chairman of the NEO committee of the Association of Space Explorers (ASE), believes that any decisionmaking process must be international in nature. He notes that, in the process of deflecting an asteroid initially on a course to hit one country, the risk of an impact might temporarily shift to another country during the course of the deflection. Moreover, such decisions might have to be made long before the probability of an impact becomes one in order to have enough time to deflect the object. That means all the countries involved need to have a say in the decisionmaking process, even if they are not involved with the deflection itself, and with more potentially hazardous NEOs to be discovered in the years to come, more and more countries will face the risks of an impact. “Inherently every nation is going to be involved in making this decision,” said Schweickart at the AAAS conference. “There is one agency, namely the United Nations, which therefore has got get involved in this decisionmaking process.”


Schweickart said he doesn’t know what that decisionmaking process should be, but he is embarking on an effort to help develop one. His ASE NEO committee is planning a series of four workshops, starting in May in Strasbourg, France, to bring together experts to determine what the best approach might be. The goal of this effort is to present to the United Nations in 2009 a proposed treaty that would serve as a protocol should the need arise.


Although Schweickart was clear to state in his AAAS presentation that the UN should be the forum for the decisionmaking process, not the body actually charged with carrying out any deflection, some interpreted his comments to suggest that he believed the UN—an organization not known for its decisive and efficient processes—should be given complete responsibility for planetary defense. “We are not in any proposing that the United Nations create a bureaucracy or that the United Nations be responsible for taking action,” he said during a public forum that was part of the Planetary Defense Conference in Washington earlier this month. The UN, though, “has to be in a position to make a timely decision” and then contract the actual task out to NASA or another organization or consortium.


This effort was prompted in large part by Apophis, even though this asteroid has only a very slim chance of posing a threat to the Earth in 2036 or beyond. New search programs, even without the dedicated telescopes that are too expensive for NASA, will in the years to come discover more and more objects that might pose a threat to the Earth years or decades from now. “Apophis is an unusual case and we may not see another one for a long time like it,” said Schweickart. “But it’s been a terrific learning experience for all of us, because it has tickled every possibility that there is in this business.”

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Jeff Foust (jeff@thespacereview.com) is the editor and publisher of The Space Review. He also operates the Spacetoday.net web site and the Space Politics and Personal Spaceflight weblogs. Views and opinions expressed in this article are those of the author alone, and do not represent the official positions of any organization or company, including the Futron Corporation, the author’s employer.

[American Patriot]

Don't look now, but an asteroid may be heading our way - in 2036

Article by: John Bachmann
Campus Reporter
• jbachman@northernstar.info

DeKALB | To borrow from Michael Stipe: Is it the end of the world as we know it?


That's what a group of engineers and scientists say could happen - even if it's a long shot. According to Reuters, an asteroid named Apophis could strike the earth on April 13, 2036.


The chance of the asteroid striking earth is 1 in 45,000, which gives some scientists reason to insist that the United Nations should take responsibility and develop a space mission to deflect the asteroid.


If the United Nations does decide to take action, the task could cost up to $300 million.


Even though the asteroid has a low probability of making an impact, NASA is updating its tracking of asteroids near Earth.


Despite the worry, NIU physics professor Dave Hedin isn't taking it too seriously.


"I don't think people should be worried at all, especially since these kinds of cases occur every year," Hedin said. "The right response that should be taken is to continue to monitor the asteroid and see what comes out of this. In reality, if the asteroid does hit Earth, there's nothing that anybody could do to prevent it from happening."


Hedin doesn't think students or people in general should waste their time worrying about something that might not even happen.


"I think there's a greater chance that a student could get hit by a Huskie Bus than this asteroid hitting Earth," Hedin said.

[American Patriot]

An inconvenient asteroid

Christopher Skeet

Issue date: 3/5/07


Move over, Al Gore. We've got a new threat to the planet the Oscars don't have a category for.

According to NASA astronomers, the asteroid Apophis might collide with Earth on April 13, 2036.

Former astronaut Rusty Schweikart is presenting a plan to the U.N. Committee on Peaceful Uses of Outer Space for a "global response" to the Apophis threat. He wants the United Nations to "adopt procedures for assessing asteroid threats and deciding if and when to take action."

NASA may not be regarding Apophis as too serious a problem if we're going to the U.N. for help.

Schweikart should remove the "when" from his plea, considering the U.N.'s inability to clear the "if" hurdle in regards to Bosnia, Rwanda, Sudan, Iraq, Iran, the Indonesian tsunami, the Hariri assassination, Hezbollah rearmament, its own stagnated reform and virtually every other issue it is being funded billions annually to deal with.

Until NASA produces compelling proof that asteroids are inhabited by third world preadolescent girls starving enough to trade sex for food, I don't foresee the blue helmet brigades taking much interest.

But let's assume Apophis is a serious threat. Astronaut Ed Lu announced that NASA's favored solution would be to build the so-called Gravity Tractor, which would be dispatched into space to exert a gravitational pull on Apophis and pull it off the collision course with Earth. Mission costs would run roughly $300 million.

It doesn't take a sandwich board prophet to predict the results of what Schweikart calls a "global response."

The U.N. will deliberate. Then they'll debate. Then they'll deliberate on whether or not to debate about deliberations and non-binding resolutions will be passed condemning asteroid activity.

When funding for the Gravity Tractor stalls, the EU will condemn America's unwillingness to shoulder more than 99.98 percent of the bill as proof of our hostility to internationalism. The Arab League will demand that a clause condemning Zionism be attached. On April 12, 2036, one day before Apophis strikes Earth, the U.N. will bring a binding resolution to vote. Russia and China will veto it.

In the meantime, outside the U.N. building in New York, some Himalayan shaman will have started a hunger strike to protest that deflecting asteroids upset the fragile spiritual balance of his temple, or something. A movement called "Gravity Emitting Tractors Assist Lying Imperialist Fascist Empires would arise, with chapters springing up at college campuses across America.

But let's get serious. If a Gravity Tractor is actually built and sent into space to deflect Apophis, the bulk of the financial and scientific support will come from the United States, with contributions from Japan, Australia and a couple European countries.

The United Nations would do little besides claim credit for the mission. So what good would it do us trying to work through the U.N. when we'll just end up doing it ourselves?

Last week, a U.N. cargo ship freighting food to Somalia was hijacked by Somali pirates and its crew held captive.

Somali patrol boats, aided by a U.S. warship, caught up to and surrounded the hijacked vessel. A few pirates who had earlier made it to land were arrested by Somali police. There's something very, very sad about the U.N., an organization representing international law and order, being bailed out by police from the most disordered, anarchic nation on the planet.

Even those who place faith in the U.N. must admit that some baby steps are needed before serious missions are undertaken.

Let the U.N. learn to overcome obstacles like ragtag pirates before raising the bar to killer asteroids.

NASA says the odds of Apophis actually striking Earth are 1 in 45,000, which aren't great, but they are better than the odds of the U.N. solving the problem.

[American Patriot]

Science in brief
Issue date: 3/19/07 Section: Science

http://media.www.thevarsity.ca/media...78-page2.shtml

Lessons in political 'science'

Pseudoscientific political ruckus broke out at last Thursday's House Committee of Science and Technology, a hearing that implicated the U.S. government for inadequatly funding many NASA programs. But space exploration was not the only hot topic of the committee.

Congressman Dana Rohrabacher, a Republican from California, wanted to prioritize the hunt for asteroids with the potential to strike and devastate Earth. He said that a fraction of the billions of dollars spent "proving" global warming should have been directed to finding and dealing with asteroid threats. A disbeliever in man-induced global warming, Rohrabacher had previously been quoted as suggesting dinosaur flatulence could have been a cause of cyclical changes in climate in the past.

Asteroid threats have been surveyed for the past decade in an international effort to detect and understand possible space-borne hazards. Last month, astronauts at the Association of Space Explorers determined that the asteroid Apophis has a one in 45,000 chance of striking Earth.

Rohrabacher also commented on recent reports from St. Petersburg's Pulkovo Astronomical Observatory implying that climactic warming on Mars and Earth-both today and in the past-could be caused by solar activity and not by man.

Rohrabacher's comments elicited responses defending scientific findings of man-induced global warming, and drew a challenge from Mark Undall, a Democrat from Colorado who demanded Rohrabacher acknowledge and move to reduce humanity's effect on climate before focusing on possible asteroid damage.

Luckily, peace was re-established by the chairman of the committee, Bart Gordon.

"NASA does not have to spend any more money proving global warming. It's already been done," he said.

After all, the $2.26 billion cut in NASA's five-year budget is a more serious matter than whether or not Rohrabacher can be made to believe in global warming.

"I think it's clear we have a budgetary situation that bears little resemblance to the rosy projections offered by the administration when the president announced his 'Vision for Space Exploration' three years ago-a vision that is now growing increasingly blurred," concluded Gordon.

Source: New Scientist and Committee on Science and Technology news service

-S.H.