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    Default Exoplanets

    Alien worlds abound! NASA scope finds 26 alien planets


    Published January 27, 2012
    | Space.com


    • NASA Ames/UC Santa Cruz
      This artist's concept shows an overhead view of the orbital position of the planets in systems with multiple transiting planets discovered by NASA's Kepler mission, and announced on Jan. 26, 2012. All the colored planets have been verified. The planet candidates shown in grey have not yet been verified.


    NASA's prolific planet-hunting spacecraft has hit the jackpot again, discovering 11 new planetary systems with 26 confirmed alien planets among them.
    The findings nearly double the number of bona fide planets found outside our solar system by the Kepler space observatory.
    "Prior to the Kepler mission, we knew of perhaps 500 exoplanets across the whole sky," Doug Hudgins, Kepler program scientist at NASA headquarters in Washington, said in a statement. "Now, in just two years staring at a patch of sky not much bigger than your fist, Kepler has discovered more than 60 planets and more than 2,300 planet candidates. This tells us that our galaxy is positively loaded with planets of all sizes and orbits."
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    The newly detected worlds vary in size from 1.5 times the radius of Earth to larger than Jupiter; 15 of the 26 planets fall between Earth and Neptune in size. While all of the planets tightly orbit their parent stars, more research will be required to determine which worlds are rocky like Earth, and which have thick, gaseous atmospheres like Neptune, the scientists said.
    Still, all of the 26 new planets orbit closer to their stars than Venus does to our sun. This means that their orbital periods or the time it takes for them to complete one orbital lap around the star range from six days to 143 days, according to the researchers. [Gallery: A World of Kepler Planets ]
    By studying these different planetary systems, scientists can glean valuable information about how planets form.
    Hunting for planets
    The Kepler spacecraft, which orbits the sun, stares at a patch of sky that contains 150,000 stars and locates potential alien planets by measuring the tiny change in brightness that occurs when a planet transits that is, passes in front of a star.
    Once a planetary candidate is identified, further observations are conducted by ground-based observatories to weed out the false positives.
    "Confirming that the small decrease in the star's brightness is due to a planet requires additional observations and time-consuming analysis," Eric Ford, associate professor of astronomy at the University of Florida, explained in a statement.
    Ford is the lead author of a study that confirms two of the new systems, Kepler-23 and Kepler-24.
    "We verified these planets using new techniques that dramatically accelerated their discovery," Ford said.
    Each of the newly found planetary systems holds two to five closely spaced transiting planets, the researchers said. Since these systems are tightly packed, the planets exert gravitational forces on one another, speeding up or slowing down their orbits. The orbital period of each planet is altered in the process.
    By measuring the orbital changes, Kepler can identify potential planets in the system. This method, known as Transit Timing Variation, can be used to verify alien planets without extensive ground-based observations. The technique also increases Kepler's ability to confirm planetary systems around fainter and more distant stars, the researchers said. [Video: Kepler Reveals Lots of Planets: Some Habitable?]
    "By precisely timing when each planet transits its star, Kepler detected the gravitational tug of the planets on each other, clinching the case for 10 of the newly announced planetary systems," Dan Fabrycky, of the University of California, Santa Cruz, said in a statement.
    Fabrycky is the lead author of the paper that confirms the Kepler-29, -30, -31 and -32 systems.
    Alien planets and their host stars
    Five of the systems (Kepler-25, -27, -30, -31 and -33) contain a pair of planets, the inner one circling its star twice in the time it takes the outer planet to make one lap.
    Four of the systems (Kepler-23, -24, -28 and -32) are home to a pair of planets where the outer one orbits the star twice for every three times the inner planet circles the parent star.
    "These configurations help to amplify the gravitational interactions between the planets, similar to how my sons kick their legs on a swing at the right time to go higher," Jason Steffen, a postdoctoral fellow at Fermilab Center for Particle Astrophysics in Batavia, Ill., said in a statement. Steffen is the lead author of a paper confirming the Kepler-25, -26, -27 and -28 systems.

    The system with the most planets is Kepler-33. The star, which is older and more massive than the sun, hosts five planets that range in size from 1.5 to five times that of Earth. All of these planets orbit closer to their star than any planet circles our sun.
    Once the properties of a star are understood, such as the telltale light signature of a planet crossing in front, it becomes easier to eliminate false positives, the researchers said.

    "The approach used to verify the Kepler-33 planets shows the overall reliability is quite high," said Jack Lissauer, planetary scientist at NASA Ames Research Center at Moffett Field, Calif., and lead author of the paper on Kepler-33. "This is a validation by multiplicity."
    The newly discovered planets increase the Kepler mission's tally of confirmed planets to 61, with 2,326 other planetary candidates.
    The four separate papers appear in the Astrophysical Journal and the Monthly Notices of the Royal Astronomical Society.





    Read more: http://www.foxnews.com/scitech/2012/...#ixzz1khR70bRq
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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    Sounds good! Now, when do we leave?

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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    About Thursday.... or was it Xeorpedf?

    I forget.
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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    they should really change focus to looking for planets around stars like Sol. I think we've got it down that there are planets around most stars, let's see if we can find some planets around sun-like stars now.

    they should probably start to coordinate with SETI also. One of you become president so you can put me in charge of NASA....

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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    hehehehe good idea.
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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    New alien planet is perfect for life, scientists say

    By Denise Chow
    Published February 02, 2012
    | Space.com



    • Carnegie Institution for Science
      An artist's conception of the alien planet GJ 667Cc, which is located in the habitable zone of its parent star.


    A potentially habitable alien planet — one that scientists say is the best candidate yet to harbor water, and possibly even life, on its surface — has been found around a nearby star.
    The planet is located in the habitable zone of its host star, which is a narrow circumstellar region where temperatures are neither too hot nor too cold for liquid water to exist on the planet's surface.

    "It's the Holy Grail of exoplanet research to find a planet around a star orbiting at the right distance so it's not too close where it would lose all its water and boil away, and not too far where it would all freeze," Steven Vogt, an astronomer at the University of California, Santa Cruz, told SPACE.com. "It's right smack in the habitable zone — there's no question or discussion about it. It's not on the edge, it's right in there."
    Vogt is one of the authors of the new study, which was led by Guillem Anglada-Escudé and Paul Butler of the Carnegie Institution for Science, a private, nonprofit research organization based in Washington, D.C.
    "This planet is the new best candidate to support liquid water and, perhaps, life as we know it," Anglada-Escudé said in a statement.
    An alien super-Earth
    The researchers estimate that the planet, called GJ 667Cc, is at least 4.5 times as massive as Earth, which makes it a so-called super-Earth. It takes roughly 28 days to make one orbital lap around its parent star, which is located a mere 22 light-years away from Earth, in the constellation Scorpius (the Scorpion).
    "This is basically our next-door neighbor," Vogt said. "It's very nearby. There are only about 100 stars closer to us than this one."
    Interestingly enough, the host star, GJ 667C, is a member of a triple-star system. GJ 667C is an M-class dwarf star that is about a third of the mass of the sun, and while it is faint, it can be seen by ground-based telescopes, Vogt said. [Gallery: The Strangest Alien Planets]
    "The planet is around one star in a triple-star system," Vogt explained. "The other stars are pretty far away, but they would look pretty nice in the sky."
    The discovery of a planet around GJ 667C came as a surprise to the astronomers, because the entire star system has a different chemical makeup than our sun. The system has much lower abundances of heavy elements (elements heavier than hydrogen and helium), such as iron, carbon and silicon.
    "It's pretty deficient in metals," Vogt said. "These are the materials out of which planets form — the grains of stuff that coalesce to eventually make up planets — so we shouldn't have really expected this star to be a likely case for harboring planets."
    The fortuitous discovery could mean that potentially habitable alien worlds could exist in a greater variety of environments than was previously thought possible, the researchers said.
    "Statistics tell us we shouldn't have found something this quickly this soon unless there's a lot of them out there," Vogt said. "This tells us there must be an awful lot of these planets out there. It was almost too easy to find, and it happened too quickly."
    The detailed findings of the study will be published in the Astrophysical Journal Letters.
    An intriguing star system
    Another super-Earth that orbits much closer to GJ 667C was previously detected in 2010, but the finding was never published, Vogt added. This planet, called GJ 667Cb, takes 7.2 days to circle the star but its location makes it far too hot to sustain liquid water on its surface.
    "It's basically glowing cinders, or a well-lit charcoal," Vogt said. "We know about a lot of these, but they're thousands of degrees and not places where you could live."
    But, the newly detected GJ 667Cc planet is a much more intriguing candidate, he said.
    "When a planet gets bigger than about 10 times the size of the Earth, there's a runaway process that happens, where it begins to eat up all the gas and ice in the disk that it's forming out of and swells quickly into something like Uranus, Jupiter or Saturn," Vogt explained. "When you have a surface and the right temperature, if there's water around, there's a good chance that it could be in liquid form. This planet is right in that sweet spot in the habitable zone, so we've got the right temperature and the right mass range."
    Preliminary observations also suggest that more planets could exist in this system, including a gas giant planet and another super-Earth that takes about 75 days to circle the star. More research will be needed to confirm these planetary candidates, as well as to glean additional details about the potentially habitable super-Earth, the scientists said.
    Finding nearby alien planets
    To make their discovery, the researchers used public data from the European Southern Observatory combined with observations from the W.M. Keck Observatory in Hawaii and the new Carnegie Planet Finder Spectrograph at the Magellan II Telescope in Chile.
    Follow-up analyses were also made using a planet-hunting technique that measures the small dips, or wobbles, in a star's motion caused by the gravitational tug of a planet.
    "With the advent of a new generation of instruments, researchers will be able to survey many M dwarf stars for similar planets and eventually look for spectroscopic signatures of life in one of these worlds," Anglada-Escudé said in a statement. Anglada-Escudé was with the Carnegie Institution for Science when he conducted the research, but has since moved on to the University of Gottingen in Germany.
    With the GJ 667C system being relatively nearby, it also opens exciting possibilities for probing potentially habitable alien worlds in the future, Vogt said, which can't easily be done with the planets that are being found by NASA's prolific Kepler spacecraft.
    "The planets coming out of Kepler are typically thousands of light-years away and we could never send a space probe out there," Vogt said. "We've been explicitly focusing on very nearby stars, because with today's technology, we could send a robotic probe out there, and within a few hundred years, it could be sending back picture postcards."





    Read more: http://www.foxnews.com/scitech/2012/...#ixzz1lGJPacQK
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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    perfect, have seti aim their scopes at it for a year i say.

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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    good idea....

    http://www.seti.org/
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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    Super-Earths 'In The Billions'
    There could be many billions of planets not much bigger than Earth circling faint stars in our galaxy, says an international team of astronomers.

    March 28, 2012

    The estimate for the number of "super-Earths" is based on detections already made and then extrapolated to include the Milky Way's population of so-called red dwarf stars.

    The team works with the high-precision Harps instrument.

    This is fitted to the 3.6m telescope at the Silla Observatory in Chile.

    Harps employs an indirect method of detection that infers the existence of orbiting planets from the way their gravity makes a parent star appear to twitch in its motion across the sky.

    "Our new observations with Harps mean that about 40% of all red dwarf stars have a super-Earth orbiting in the habitable zone where liquid water can exist on the surface of the planet," said team leader Xavier Bonfils from the Observatoire des Sciences de l'Univers de Grenoble, France.

    "Because red dwarfs are so common - there are about 160 billion of them in the Milky Way - this leads us to the astonishing result that there are tens of billions of these planets in our galaxy alone."

    The Harps team came up with its numbers after surveying 102 carefully chosen red dwarfs, which are dimmer and cooler than our Sun.

    The group found a total of nine super-Earths (which are defined as planets with one to 10 times the mass of the Earth), with two judged to be orbiting inside their stars' habitable zones.

    Putting all its data together, including observations of stars that did not have planets, the team was able to produce an estimate for how common different sorts of planets are around red dwarfs.

    This assessment suggests super-Earths in the habitable zone occur in 41% of cases, with a range from 28% to 95%.

    Given how many red dwarf stars there are in close proximity to the Sun, it means there could be perhaps 100 super-Earth planets in the habitable zones of stars that are less than about 30 light-years distant.

    It raises the obvious question as to whether any of these planets are not just habitable but do indeed host life.

    Because red dwarfs are relatively dim and cool, their habitable zones are closer in to the star than the Earth finds itself to the Sun.

    But red dwarfs are known to be prone to stellar eruptions, or flares, which could bathe a nearby planet in X-rays or ultraviolet radiation, and that might make life there less likely.

    "We already have ideas to find traces of life on these planets," commented co-researcher Stephane Udry from Geneva Observatory.

    "If we are lucky to have an eclipse of the star by the planet - it's called a transit - then the light of the star will be going through the atmosphere of the planet before coming to Earth.

    "This light will carry information about the chemical composition of the atmosphere.

    "If we can see traces of elements related to life such as oxygen in that light, then we could get some clues that there is life on that planet.

    "But we will need some big telescopes and probably in space," he told the BBC's Science In Action programme.

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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    Scientists estimate billions of habitable planets in Milky Way




    This artist's impression shows a sunset seen from the super-Earth Gliese 667 Cc. (ESO / L. Calcada / March 28, 2012)


    By Deborah Netburn March 28, 2012, 1:17 p.m.



    Looking for a new planet to colonize? A team of European astronomers says you've got options -- billions of them.


    Using results from the High Accuracy Radical Velocity Planet Searcher (HARPS) at the European Southern Observatory, the scientists say there are likely tens of billions of planets in the Milky Way galaxy alone that may be able to sustain life.


    They estimate that one hundred of those planets are in the sun's immediate neighborhood -- which in space-speak is 30 light years away.


    The generally accepted (though perhaps shortsighted) definition of a planet that can sustain life is one that has a mass between one and 10 times that of Earth, as well as a rocky surface, and the ability to sustain liquid water -- meaning the planet's surface temperature is neither too hot that water would evaporate nor too cold that it would freeze.


    Although there are no planets that meet those criteria in our own solar system, the report suggests that they are common around other stars.


    For this study, scientists focused exclusively on finding planets orbiting red dwarf stars, which are fainter and cooler than our sun, but which make up 80% of the stars in the Milky Way.


    After surveying a carefully chosen sample of red dwarf stars over a period of six years, the team concluded that 40% of all red dwarf stars have rocky planets roughly the same size of the Earth located in the "habitable zone."


    "Because red dwarfs are so common -- there are 160 billion of them in the Milky way -- this leads us to the astonishing result that there are tens of billions of these planets in our galaxy alone," Xavier Bonfils, the French astronomer who led the research team, said in a statement.


    There is a caveat, however, and it's kind of a big one.


    Since red dwarfs are cooler than our sun, a planet would have to be much closer to the star than Earth is to the sun] in order for the planet's surface to be warm enough to sustain liquid water.


    And as team member Stephane Udry of Geneva University notes, the planet may then be all the more susceptible to the "stellar eruptions or flares, which may bathe the planet in X-rays or ultraviolet radiation, and which may make life there less likely."


    Which leads us to conclude that there is no place like home.
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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    I'm ready to go start New America...

    Liberals need not apply.

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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    /snicker

    Hey, what with the ability to build an "Enterprise" with Ion Engines, you could get there in... say, 2 or 3 centuries at the nearest one.

    You know... thinking about this, I'd love to pack it up and head for a new world myself. Let me know how it works out.
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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    You know Ryan, I was thinking about this. Building a ship in space would cost a lot (something like that "Enterprise" idea the guy came up with) - but once built, it could carry a lot of food, supplies, systems to clean air/oxygen and CO2, use the byproducts to feed hydroponics and hydroponics to feed the people/critters.

    You could get to Mars in about 40 days.

    Ion propulsion has proved to work. An ion engine would suck in hydrogen and be ionized, thrust out the back of the engine and slowly increase the speed of the vessel until it approaches light speed.

    Not WARP technology, but absolutely would work.

    Of course anyone aboard the ship wouldn't be coming back to anything they recognized, ever. Once you start bending space-time you no longer belong to the place you left!

    So, things would slow down for you - but speed up for us back on Earth. We'd experience normal time, and the so would the space ship. But we'd not experience it at the same time.

    For us on Earth, we'd never hear from the "Enterprise" again.... and they'd leave everything they ever knew - including perhaps a living Earth. If they came back they might find us millions of years advanced, and not even look like humans!

    lol
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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    And here is an article to help out

    How Long Would it Take to Travel to the Nearest Star?

    by Ian O'Neill on July 8, 2008

    Tweet7




    We’ve all asked this question at some point: How long would it take to travel to the stars? And could I do it in my lifetime? There are many answers to this possibility, some very simple, others in the realms of science fiction. To make this easier to answer, we’ll address how long it would take to travel to the nearest star to the solar system, Proxima Centauri. Unfortunately, any route you take to the stars will be slow, even if you are powered by the most powerful nuclear propulsion technology…






    In April, I examined how long it takes to travel to the Moon. We took the fast-track with New Horizons Pluto mission, powering past Earth’s only natural satellite in a mere eight hours and 35 minutes. We also had the leisurely ion drive-propelled SMART-1 mission that trundled its way to the Moon for 13 months. So, from the speedy rocket-propelled spacecraft to the economical ion drive, we have a few options open to us when flying around local space (plus we could use Jupiter or Saturn for a hefty gravitational slingshot). But say if we build a dedicated mission to somewhere a little more extreme?






    The nearest star to Earth is our Sun. It is a fairly “average” star in the Hertzsprung – Russell diagram’s “Main Sequence.” Our Sun is surprisingly stable, providing Earth with just the right sunlight for life to evolve on our planet. We know there are planets orbiting other stars near to the Solar System, but could they support life as efficiently as our Sun? In the future, should mankind wish to leave the Solar System, we’ll have a huge choice of stars we could travel to, and many could have the right conditions for life to thrive. But where would we go and how long would it take for us to get there?


    First choice would probably be Proxima Centauri, the closest star to the Solar System. Part of a triple star system called Alpha Centauri; Proxima is 4.22 light years from Earth. Alpha Centauri is actually the brightest star of the three in the system, and so the system is named after this star. Alpha Centauri is part of a closely orbiting binary about 4.37 light years from Earth, but Proxima Centauri (the dimmest of the three) is an isolated red dwarf star 0.15 light years from the binary. Red dwarf stars generate far less energy than our Sun, so we’d have to find a planet in a closer orbit to this red dwarf to sustain life as we know it.





    Interstellar travel probably conjures up some outlandish theories about the technology we could use to get there. Star Trek‘s warp drive will have to wait and stay in the “sci-fi” category for now, it is more likely any deep space trip will take generations rather than a few days. So, starting with one of the slowest forms of space travel, how long will it take to get to Proxima Centauri? Remember, this is all conjecture as there is currently no benchmark for interstellar trips…

    Slowest: Ion drive propulsion, 81,000 years



    Ion drive propulsion was considered to be science fiction only a few decades ago. In recent years however, the technology to support ion propulsion has moved from theory and into practice in a big way. The ESA SMART-1 mission for example successfully completed its mission to the Moon after taking a 13 month spiral path from the Earth. SMART-1 used solar powered ion thrusters, where electrical energy was harvested from its solar panels and used to power its Hall-effect thrusters. Only 82 kg of xenon propellant was used to propel SMART-1 to the Moon. 1 kg of xenon propellant provided a delta-v of 45 m/s. This is a highly efficient form of propulsion, but it is by no means fast.



    One of the first missions to use ion drive technology was the 1998 Deep Space 1 mission to Comet Borrelly. DS1 also used a xenon-powered ion drive, consuming 81.5 kg of propellant. Over 20 months of thrusting, DS1 was designed to reach a cometary flyby velocity of 56,000 km/hr (35,000 miles/hr).



    Ion thrusters are therefore more economical than rocket technology as the thrust per unit mass of propellant (a.k.a. specific impulse) is far higher, but it takes a long time for ion thrusters to accelerate spacecraft to any great velocity. As the maximum velocity of ion thruster-powered spacecraft depends on the amount of fuel it can carry and the amount of electricity it can generate, although slow, if ion thrusters were to be used for a non-time critical mission to Proxima Centauri, the ion thrusters would need a huge source of energy production (i.e. nuclear power) and a large quantity of propellant (although not as large as less-economical forms of space travel, such as rockets). As interstellar ion engines do not exist yet, I will quickly calculate how long it would take for an interplanetary ion engine spacecraft, like Deep Space 1 to travel to our nearest stellar neighbour.





    Assuming all the 81.5 kg of xenon propellant translates into a maximum velocity of 56,000 km/hr (assuming there is no other forms of propulsion, such as a gravitational slingshot, and this velocity remains constant for the duration of the journey), Deep Space 1 would take over 81,000 years to travel the 4.3 light years (or 1.3 parsecs) from Earth to Proxima Centauri. To put that time-scale into perspective, that would be over 2,700 human generations. So I think we can categorically say, interplanetary ion engine mission speeds are far too tiny to be considered for manned interstellar missions. But, should ion thrusters be made bigger and more powerful (i.e. ion exhaust velocity would need to be higher), with enough propellant for the spacecraft’s entire 4.3 light year trip, the 81,000 years would be greatly reduced.


    Fastest: Gravitational assists, 19,000 years


    The 1976 Helios 2 mission was launched to study the interplanetary medium from 0.3AU to 1AU to the Sun. At the time, Helios 1 (launched in 1974) and Helios 2 held the record for closest approach to the Sun. However, to this day, Helios 2 holds the record for fastest ever spacecraft to travel in space. Helios 2 was launched by a conventional NASA Titan/Centaur launch vehicle (the craft itself was built in Germany) and placed in a highly elliptical orbit. Due to the large eccentricity (e=0.54) of the 190 day solar orbit, at perihelion Helios 2 was able to reach a maximum velocity of over 240,000 km/hr (150,000 miles/hr). This orbital speed was attained by the gravitational pull of the Sun alone.



    Gravitational assists are a very useful spaceflight technique, especially when using the Earth or massive planets for a much needed boost in velocity. The Voyager 1 probe for example used Saturn and Jupiter for gravitational slingshots to attain its current 60,000 km/hr (38,000 miles/hr) interstellar velocity. Technically, the Helios 2 perihelion velocity was not a gravitational slingshot, it was a maximum orbital velocity, but it still holds the record for being the fastest manmade object regardless.


    So, if Voyager 1 was travelling in the direction of the red dwarf Proxima Centauri, how long would it take to get there? At a constant velocity of 60,000 km/hr, it would take 76,000 years (or over 2,500 generations) to travel that distance. And what if we could attain the record-breaking speed of Helios 2′s close approach of the Sun? Travelling at a constant speed of 240,000 km/hr, Helios 2 would take 19,000 years (or over 600 generations) to travel 4.3 light years.


    Again, these speeds are prohibitively slow for any quick forms of transportation to the stars. Other technologies are required (wormholes, warp drives and teleportation will remain in the “sci-fi” drawer for now)…


    Fastest (theoretical): Nuclear Pulse Propulsion, 85 years


    Nuclear pulse propulsion is a theoretically possible form of fast space travel. Very early on in the development of the development of the atomic bomb, nuclear pulse propulsion was proposed in 1947 and Project Orion was born in 1958 to investigate interplanetary space travel. In a nutshell, Project Orion hoped to harness the power of pulsed nuclear explosions to provide a huge thrust with very high specific impulse. It is a major advantage to extract maximum energy from a spacecraft’s fuel to minimize cost and maximize range, therefore a high specific impulse creates faster, longer-range spaceflight for minimum investment.

    For archived prototype video of pulsed propulsion using conventional explosives, watch this video »


    The Partial Test Ban Treaty of 1963 is largely attributed to the cancellation of Project Orion (due to the obvious design flaw that huge amounts of radioactive waste would be pumped into space), but what kind of velocities could a nuclear pulse propulsion spaceship attain? Some estimates suggest a ballpark figure of 5% the speed of light (or 5.4×107 km/hr). So assuming a spacecraft could travel at these speeds, it would take a Project Orion-type craft approximately 85 years to travel from the Earth to Proxima Centauri.


    In conclusion, if you were hoping to travel to the nearest star within your lifetime, the outlook isn’t very good. However, if mankind felt the incentive to build an “interstellar ark” filled with a self-sustaining community of space-faring humans, it might be possible to travel there in a little under a century if we developed nuclear pulse technology. So your descendents may touch down on a planet closely orbiting Proxima Centauri, but unless we make a breakthrough in interstellar travel (and science fiction becomes more like science fact), we’ll be stuck with long-term, pedestrian transits for the foreseeable (and distant) future…
    Sources:
    NASA
    ESA SMART 1
    NASA Helios 2


    Read more: http://www.universetoday.com/15403/h...#ixzz1xtWg8D4u
    Libertatem Prius!


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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    To date there have been almost 1000 exo-planets discovered.

    Here's the first cloud structure being mapped.

    First Cloud Map of a Planet Beyond our Solar System

    Posted by Andrew Fazekas in StarStruck on October 1, 2013

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    Kepler-7b (left), which is 1.5 times the radius of Jupiter (right), is the first exoplanet to have its clouds mapped. The cloud map was produced using data from NASA’s Kepler and Spitzer space telescopes. Image credit: NASA/JPL-Caltech/MIT



    After cataloging nearly a thousand worlds beyond our solar system, astronomers can now for the first time forecast cloudy skies on a distant exoplanet.

    While the above image may not resemble a weather map, it shows a first look at clouds on a hot, Jupiter-like world dubbed Kepler 7b, which resides nearly 1000 light years away from Earth.


    By combining three years worth of infrared and visual observations from NASA’s Spitzer and Kepler space telescopes, a low -resolution map was stitched together showing high clouds in the gas giant’s western hemisphere. The planet’s eastern side sports clear skies, instead.

    While a sticky gyroscope wheel has sidelined Kepler, it has banked four years of data on thousands of candidate planets still awaiting analysis. Kepler 7b was one of the first of more than 150 confirmed exoplanets that Kepler has discovered. Before it lost its bearings, the space telescope was able to see Kepler-7b undergoing phases changes like the waxing and waning of the moon and spy a mysterious bright spot on its western hemisphere. All of this was detected as the planet zipped around its parent star, circling it completely in just under 7 days.


    Not able to tell if the bright spot was due to clouds or heat, astronomers swung Spitzer into action. Spitzer measured the planet’s temperature, which led the astronomers to confirm that the source of light was due to its host star’s light bouncing off the cloud tops on its western sun-facing hemisphere.


    “Kepler-7b reflects much more light than most giant planets we’ve found, which we attribute to clouds in the upper atmosphere,” said Thomas Barclay, Kepler scientist at NASA’s Ames Research Center in a press release.


    “Unlike those on Earth, the cloud patterns on this planet do not seem to change much over time — it has a remarkably stable climate.” Hopes are that this same observation techniques can be applied to smaller, more Earth-like worlds.

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    Default Re: Alien worlds abound! NASA scope finds 26 alien planets

    Here's a piece of information:

    An extrasolar planet, or exoplanet, is a planet outside the Solar System. Around a thousand such planets have been discovered (990 planets in 754 planetary systems including 168 multiple planetary systems as of 30 September 2013)

    An image of three planets:


    An infrared image of the HR 8799 system. The central blob is noise left over after light from the star has been largely removed. The three known planets can be seen: HR 8799d (bottom), HR 8799c (upper right), and HR 8799b (upper left).




    This one has water:

    http://www.pcmag.com/article2/0,2817,2424036,00.aspScientists Discover Signs of Water on Nearby Planet



    Is there a water planet just 42 light years from Earth? Japanese scientists this week said their investigations of a nearby exoplanet suggest it "is likely to have a water-rich atmosphere."


    Gliese 1214 b (GJ 1214 b), discovered in 2009, is a so-called super-Earth—an extrasolar planet that's larger and more massive than our own but significantly smaller than icy giants like Uranus or Neptune. Not much is known about super-Earths, how they form, or why our own solar system doesn't have one despite their apparent prevalence in other star systems.


    But now it appears that we may have a better idea of the atmospheric conditions on at least one of them. GJ 1214-b is located in the constellation Ophiuchus and is about 2.5 times the size of Earth and about seven times more massive.


    While GJ 1214-b isn't listed as a prime candidate for life among known exoplanets orbiting within their stars' habitable zones, it was suspected of having liquid water from the time of its discovery.

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    Default At Least 8.8 Billion Earth-Size, Just-Right Planets Found, Study Says

    At Least 8.8 Billion Earth-Size, Just-Right Planets Found, Study Says

    November 5, 2013

    Space is vast, but it may not be so lonely after all: A study finds the Milky Way is teeming with billions of planets that are about the size of Earth, orbit stars just like our sun, and exist in the Goldilocks zone -- not too hot and not too cold for life.

    Astronomers using NASA data have calculated for the first time that in our galaxy alone, there are at least 8.8 billion stars with Earth-size planets in the habitable temperature zone.

    The study was published Monday in the journal Proceedings of the National Academy of Science.

    For perspective, that's more Earth-like planets than there are people on Earth.

    As for what it says about the odds that there is life somewhere out there, it means "just in our Milky Way galaxy alone, that's 8.8 billion throws of the biological dice," said study co-author Geoff Marcy, a longtime planet hunter from the University of California at Berkeley.

    The next step, scientists say, is to look for atmospheres on these planets with powerful space telescopes that have yet to be launched. That would yield further clues to whether any of these planets do, in fact, harbor life.

    The findings also raise a blaring question, Marcy said: If we aren't alone, why is "there a deafening silence in our Milky Way galaxy from advanced civilizations?"

    In the Milky Way, about 1 in 5 stars that are like our sun in size, color and age have planets that are roughly Earth's size and are in the habitable zone where life-crucial water can be liquid, according to intricate calculations based on four years of observations from NASA's now-crippled Kepler telescope.

    If people on Earth could only travel in deep space, "you'd probably see a lot of traffic jams," Bill Borucki, NASA's chief Kepler scientist, joked Monday.

    The Kepler telescope peered at 42,000 stars, examining just a tiny slice of our galaxy to see how many planets like Earth are out there. Scientists then extrapolated that figure to the rest of the galaxy, which has hundreds of billions of stars.

    For the first time, scientists calculated -- not estimated -- what percent of stars that are just like our sun have planets similar to Earth: 22 percent, with a margin of error of plus or minus 8 percentage points.

    Kepler scientist Natalie Batalha said there is still more data to pore over before this can be considered a final figure.

    There are about 200 billion stars in our galaxy, with 40 billion of them like our sun, Marcy said. One of his co-authors put the number of sun-like stars closer to 50 billion, meaning there would be at least 11 billion planets like ours.

    Based on the 1-in-5 estimate, the closest Earth-size planet that is in the habitable temperature zone and circles a sun-like star is probably within 70 trillion miles of Earth, Marcy said.

    And the 8.8 billion Earth-size planets figure is only a start. That's because scientists were looking only at sun-like stars, which are not the most common stars.

    An earlier study found that 15 percent of the more common red dwarf stars have Earth-size planets that are close-in enough to be in the not-too-hot, not-too-cold Goldilocks Zone.

    Put those together and that's probably 40 billion right-size, right-place planets, Marcy said.

    And that's just our galaxy. There are billions of other galaxies.

    Scientists at a Kepler science conference Monday said they have found 833 new candidate planets with the space telescope, bringing the total of planets they've spotted to 3,538, but most aren't candidates for life.

    Kepler has identified only 10 planets that are about Earth's size circling sun-like stars and are in the habitable zone, including one called Kepler 69-c.

    Because there are probably hundreds of planets missed for every one found, the study did intricate extrapolations to come up with the 22 percent figure -- a calculation that outside scientists say is fair.

    "Everything they've done looks legitimate," said MIT astronomer Sara Seager.

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    Default Re: At Least 8.8 Billion Earth-Size, Just-Right Planets Found, Study Says

    I posted that already (or an article like it!)


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    Default Re: At Least 8.8 Billion Earth-Size, Just-Right Planets Found, Study Says

    I thought so after I posted it. I know it isn't exactly breaking news. Clearing out saved news articles I've got and haven't had a chance to post.

    Probably should have gone with my gut and searched. I'll close this one down.

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    Default Re: At Least 8.8 Billion Earth-Size, Just-Right Planets Found, Study Says

    No biggie. I think I posted it in Science (or maybe space depending on where I go the material). But I wouldn't bother closing it.

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