An artist's illustration of an Earth-like planet. The search for planets that are similar to Earth is one of NASA's main goals. Many planets have already been discovered orbiting other stars, but so far only larger planets (the size of Jupiter or larger) have been found. New missions are being planned by NASA which will be able to detect smaller Earth-sized planets. Some of these missions will also try to detect signs of life on these planets by studying emissions in their atmospheres.


Super-Earth's atmosphere analyzed for first time


Scientists say alien air likely to be thick with water vapor, or haze

The first-ever analysis of the atmosphere of an alien planet classified as a so-called "super-Earth" has revealed a distant world that is likely covered with either water vapor or a thick haze, scientists announced Wednesday.

The exoplanet GJ 1214b, which orbits a star 40 light-years from Earth, offers astronomers a unique chance to study its atmosphere because it passes directly in front of its parent star from Earth's line of sight. That means that once an orbit, the star's light is filtered as it passes through the planet's atmosphere on its way to Earth, taking with it an imprint from the chemicals there. [ Illustration of alien planet GJ 1214b]

"We're trying to get at, what's the main component of this planet's atmosphere?" said lead researcher Jacob Bean, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

GJ 1214b is called a super-Earth because it is larger than our home planet, but still smaller than gas giants like Jupiter and Saturn. It was first discovered in 2009 and has been studied ever since.

A watery super-Earth?

In a comparison with our solar system's inhabitants, GJ 1214b most closely resembles Neptune, Bean said. The alien planet has a radius 2.5 times the size of Earth's and is about 6.5 times the mass of our planet, researchers said.

Astronomers have discovered more than 500 alien planets beyond our solar system so far, with hundreds more expected to be confirmed in upcoming months.

Read the full story here:

For more information:
First Super-Earth Atmosphere Analyzed
First super-earth atmosphere analysis shows water may exist


Odds of Life on Newfound Earth-Size Planet '100 Percent,' Astronomer Says

29 September 2010

An Earth-size planet has been spotted orbiting a nearby star at a distance that would makes it not too hot and not too cold — comfortable enough for life to exist, researchers announced today (Sept. 29).

If confirmed, the exoplanet, named Gliese 581g, would be the first Earth-like world found residing in a star's habitable zone — a region where a planet's temperature could sustain liquid water on its surface. [Illustration of planet Gliese 581g.]

And the planet's discoverers are optimistic about the prospects for finding life there.

"Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say, my own personal feeling is that the chances of life on this planet are 100 percent," said Steven Vogt, a professor of astronomy and astrophysics at the University of California, Santa Cruz, during a press briefing today. "I have almost no doubt about it."

Read the full story here:

For more information:

New Earth-like planet discovered
Gliese 581g is in the 'Goldilocks zone' of its solar system, where liquid water could exist, and is a strong contender to be a habitable world

Earth-Like Planet Can Sustain Life
Located in a solar system that parallels our own, the new world could be habitable -- or even inhabited.

New Planet: There's Life! See Video!
Michio Kaku: Earth-Like Planet Discovered See Video!
Newly discovered planet to save human race See Video!

To learn more about: Gliese 581 Solar System.


Can We Spot Volcanoes on Alien Worlds? Astronomers Say Yes

SOURCE: Harvard-Smithsonian Center for Astrophysics
September 07, 2010

Cambridge, MA - Volcanoes display the awesome power of Nature like few other events. Earlier this year, ash from an Icelandic volcano disrupted air travel throughout much of northern Europe. Yet this recent eruption pales next to the fury of Jupiter's moon Io, the most volcanic body in our solar system.

Now that astronomers are finding rocky worlds orbiting distant stars, they're asking the next logical questions: Do any of those worlds have volcanoes? And if so, could we detect them? Work by theorists at the Harvard-Smithsonian Center for Astrophysics suggests that the answer to the latter is a qualified "Yes."

"You would need something truly earthshaking, an eruption that dumped a lot of gases into the atmosphere," said Smithsonian astronomer Lisa Kaltenegger. "Using the James Webb Space Telescope, we could spot an eruption 10 to 100 times the size of Pinatubo for the closest stars," she added.

Read the full story here:


706 Earthlike Planets Discovered By NASA Spacecraft‏

18 June 2010

NASA's Kepler spacecraft hunting for Earth-like planets around other stars has found 706 candidates for potential alien worlds while gazing at more than 156,000 stars packed into a single patch of the sky.

If all 706 of these objects pass the stringent follow-up tests to determine if they are actually planets, and not false alarms, they could nearly triple the current number of known extrasolar planets. They were announced as part of a huge release of data from the mission's first 43 days by NASA's Kepler science team this week.

The Kepler space observatory monitors stars for subtle changes in their brightness, which could indicate the presence of alien planets passing in front of them as seen from Earth. Astronomers will use the newly-released data from Kepler to determine if orbiting planets are responsible for the variation in brightness of several hundred stars.

Read the full story here:

For more information:

Millions of Earths? Talk causes a stir See Video!
A World of Difference between 'Earth-Like' and 'Earth-Sized'
140 Earth-like planets discovered in the Milky Way by Kepler See Video!
Dimitar Sasselov: How we found hundreds of Earth-like planets See Video!


NASA's Kepler Space Telescope Discovers Five Exoplanets

January 04, 2010

PASADENA, Calif. -- NASA's Kepler space telescope, designed to find Earth-size planets in the habitable zone of sun-like stars, has discovered its first five new exoplanets, or planets beyond our solar system.

Kepler's high sensitivity to both small and large planets enabled the discovery of the exoplanets, named Kepler 4b, 5b, 6b, 7b and 8b. The discoveries were announced Monday, Jan. 4, by members of the Kepler science team during a news briefing at the American Astronomical Society meeting in Washington.

"These observations contribute to our understanding of how planetary systems form and evolve from the gas and dust disks that give rise to both the stars and their planets," said William Borucki of NASA's Ames Research Center in Moffett Field, Calif. Borucki is the mission's science principal investigator. "The discoveries also show that our science instrument is working well. Indications are that Kepler will meet all its science goals."

Read the full story here:

For more information:

The First Five Worlds of Kepler See Video!
Searching for Alien Earths: The Kepler Space Telescope


Earth-like planets could be found soon: astronomers

January 8, 2010

Astronomers say they are on the verge of finding planets like Earth orbiting other stars, a key step in determining if we are alone in the universe.

A top NASA official and other leading scientists say that within four or five years they should discover the first Earth-like planet where life could develop, or may have already. A planet close to the size of Earth could even be found sometime this year if preliminary hints from a new space telescope pan out.

At the annual American Astronomical Society conference this week, each discovery involving so-called "exoplanets" — those outside our solar system — pointed to the same conclusion: Quiet planets like Earth where life could develop probably are plentiful, despite a violent universe of exploding stars, crushing black holes and colliding galaxies.

NASA's new Kepler telescope and a wealth of new research from the suddenly hot and competitive exoplanet field generated noticeable buzz at the convention. Scientists are talking about being at "an incredible special place in history" and closer to answering a question that has dogged humanity since the beginning of civilization.

"The fundamental question is: Are we alone? For the first time, there's an optimism that sometime in our lifetimes we're going to get to the bottom of that," said Simon (Pete) Worden, an astronomer who heads NASA's Ames Research Center. "If I were a betting man, which I am, I would bet we're not alone — there is a lot of life."

Read the full story here:
Astronomers: We could find Earth-like planets soon


Our Milky Way Galaxy

This is our home galaxy called "Milky Way" This arrow shows us where our sun is in the galaxy.

The Milky Way is a galaxy that contains at least 200 billion stars and their planetary systems. It is an average-size galaxy of the barred spiral class. This means that there is a central bulge, with arms, which extend for several light-years*. However, the term "barred" means that its central bulge is elongated; in the Milky Way, this elongation is at a ratio of 2:3, meaning that it is about one and a half times as long as it is wide.
The Milky Way has five distinct arms protruding from the central bulge. Their names are as follows: the Cygnus Arm, Centarus Arm, Sagittarius Arm, Orion Arm, and Perseus Arm. Our solar system lies in the Orion Arm.
The Milky Way belongs to a group of galaxies that is known as the Local Group. The Local Group contains about 30 galaxies, two of which are the Andromeda Galaxy and the Triangulum Galaxy. The Local Group is 9 million light-years in diameter.
In turn, the Local Group belongs to a much larger group of galaxies which known as the Virgo Supercluster. The Milky Way lies on the outer edge of the supercluster. The Virgo Supercluster is about 100 million light-years in diameter.
The Milky Way is 100 thousand light-years in diameter. The Milky Way takes approximately 225 million years to rotate, clockwise, even though the arm that we are in is whipping around the center at about 465,000 miles an hour. At that speed, a space ship from Earth would only need a half an hour to get to the moon!

This image is of the night sky the Milky Way Galaxy.
When we look up at the night sky we can see part of the Milky Way galaxy stretching across the night sky even though we are part of the Milky Way. That is because we are located at one small part of the Milky Way Galaxy and from our position we can see the dense cloud of stars formin another piece of the Milky Way.

  Properties of the Milky Way
Diameter of the Galaxy 100,000 light years
Classification of the Galaxy SBbc
Number of stars in the Galaxy 200 billion
Mass of the Galaxy 1 trillion solar masses
Length of the central bar 25,000 light years
Distance of the Sun from the centre 26,000 light years
Thickness of the Galaxy at the Sun 2,000 light years
Velocity of Sun around the Galaxy 220 km/s
Orbital period of Sun around the Galaxy 225 million years

Below - four galaxies which look like the Milky Way. NGC 3953 (top left) is 55 million light years away and 95,000 light years in diameter. NGC 5970 (top right) is 105 million light years away and 85,000 light years in diameter. NGC 7329 (bottom left) is even further at a distance of 140 million light years but it is larger with a diameter of 140,000 light years. NGC 7723 (bottom right) is 80 million light years away with a diameter of 90,000 light years.

 How many galaxies are in the Universe?
The known universe consists of about 200 to 300 billion galaxies.
Visit this great site "We Are Not Alone" for more information about stars and galaxies.

How the Milky Way Worksclick here, here & here.
The Stars of the Milky Way
Galactic Habitable Zone

What is a light year?
*One light year is about 5,878,499,000,000 miles.

New Tourist's Guide to the Milky Way
The picture of our galaxy is constantly changing as technology improves.

Travel 10 million light years.....In 1 minutes. (Video)
Travel through your universe from outside the milky way down into the atoms which make up your world.


'Waterworld' Is Most Earth-Like Planet Yet

SOURCE: Sky News
December 16, 2009

Astronomers have discovered a new "waterworld" 40 light years away, raising the chances of the existence of Earth-like planets.

Evidence suggests it has an atmosphere, and astronomers believe it to be more like Earth than any planet found outside the Solar System so far.

Although the planet is thought to be too hot to sustain Earth-type life, it is believed to consist of 75% water.

Planet GJ1214b is six times bigger than Earth and was discovered orbiting a small faint star 1.3 million miles away.

Although its red dwarf parent star is 3,000 times less bright than the Sun, it hugs the star so closely that its surface temperature is an oven-hot 200C.

"Since this planet is so close to Earth, Hubble should be able to detect the atmosphere and determine what it's made of."

Dr David Charbonneau, from the Harvard-Smithsonian Centre

Graduate student astronomer Zachory Berta, from the Harvard-Smithsonian Centre for Astrophysics in the US, who spotted the first hints of the planet, said: "Despite its hot temperature, this appears to be a waterworld.

"It is much smaller, cooler and more Earth-like than any other known exoplanet."

He said some of the planet's water should be in the form of exotic materials such as Ice Seven - a crystalline form of water that exists at pressures greater than 20,000 times the Earth's sea-level atmosphere.

Scientists want to turn the Hubble Space Telescope towards the planet to allow astronomers to discover its composition.

Dr David Charbonneau, also from the Harvard-Smithsonian Centre, said: "Since this planet is so close to Earth, Hubble should be able to detect the atmosphere and determine what it's made of.

"That will make it the first super-Earth with a confirmed atmosphere - even though that atmosphere probably won't be hospitable to life as we know it."

The discovery is reported in the journal Nature.

This article: here.

Super-Earth: Astronomers Find a Watery New Planet


Avatar's moon Pandora could be real

SOURCE: Harvard-Smithsonian Center for Astrophysics
December 17, 2009

Cambridge, MA - In the new blockbuster Avatar, humans visit the habitable - and inhabited - alien moon called Pandora. Life-bearing moons like Pandora or the Star Wars forest moon of Endor are a staple of science fiction. With NASA's Kepler mission showing the potential to detect Earth-sized objects, habitable moons may soon become science fact. If we find them nearby, a new paper by Smithsonian astronomer Lisa Kaltenegger shows that the James Webb Space Telescope (JWST) will be able to study their atmospheres and detect key gases like carbon dioxide, oxygen, and water vapor.

"If Pandora existed, we potentially could detect it and study its atmosphere in the next decade," said Lisa Kaltenegger of the Harvard-Smithsonian Center for Astrophysics (CfA).

So far, planet searches have spotted hundreds of Jupiter-sized objects in a range of orbits. Gas giants, while easier to detect, could not serve as homes for life as we know it. However, scientists have speculated whether a rocky moon orbiting a gas giant could be life-friendly, if that planet orbited within the star's habitable zone (the region warm enough for liquid water to exist).

"All of the gas giant planets in our solar system have rocky and icy moons," said Kaltenegger. "That raises the possibility that alien Jupiters will also have moons. Some of those may be Earth-sized and able to hold onto an atmosphere."

Kepler looks for planets that cross in front of their host stars, which creates a mini-eclipse and dims the star by a small but detectable amount. Such a transit lasts only hours and requires exact alignment of star and planet along our line of sight. Kepler will examine thousands of stars to find a few with transiting worlds.

Once they have found an alien Jupiter, astronomers can look for orbiting moons, or exomoons. A moon's gravity would tug on the planet and either speed or slow its transit, depending on whether the moon leads or trails the planet. The resulting transit duration variations would indicate the moon's existence.

View: Full article
For more information:
Sci-Fi's Coolest Worlds
Avatar's 'Pandora' could be a reality
The Real Science of Avatar's Pandora
Pandora: A look at Polyphemis' Exomoon
Avatar's Pandora moon may actually exist
Avatar: A New World That NASA Is Ignoring
'Avatar': The Real-Life Science Behind the Fantasy
Newly Discovered Exoplanets Point the Way to Avatar's Pandora

Visit this great site: PANDORAPEDIA The Official Guide to Pandora.


The Alpha Centauri System and Traveling There

Articles on the Alpha Centauri system, the possibility of traveling there, and other interstellar related articles.

Alpha Centauri & here.
Destination Alpha Centauri
First Ark to Alpha Centauri
How to Get to Alpha Centauri

Traveling from Earth to the Alpha Centauri system
Voyage to Pandora: Humanity's First Interstellar Flight
The Science Behind James Cameron's Avatar Voyaging to the Stars
Cosmic Journeys: Voyage to Pandora: Interstellar Flight See Video!

To learn about Interstellar travel & here.
Spaceship Could Fly Faster Than Light
The Universe - "Science Fiction, Science Fact" See Video!
Mark Millis on the possibilities of interstellar travel See Video!

Stephen Hawking's Warning (2006)
Move to new planet, says Hawking
Humans must colonize other planets: Hawking
Stephen Hawking: Humans Must Leave Earth to Survive
Hawking Says Humans Must Colonize Other Planets to Survive

Stephen Hawking's Warning (2010) UPDATE
Stephen Hawking's Ecological Warning
Stephen Hawking's Warning: Abandon Earth—Or Face Extinction
Abandon Earth or Face Extinction, Stephen Hawking Warns -- Again

Space colonization Click here, here & here.
Space Colonization: Future or Fanatsy?
NASA preps '100-year spaceship' NEW!
Is NASA Covering Up the 100-Year Starship? NEW!
Ion engine could one day power 39-day trips to Mars
Do We Have the 'Right Stuff' to Put an Astronaut on Mars?

Space Historian Sees Cyborgs in Our Future
Future Space Explorers Could Be Humans 2.0
Humans Only Have 200-300 Years Left on Earth
Visit this great site: The Future of Human Evolution

An artist picture of a future astronaut`s 1st breath of air on an alien planet.

"The long-term survival of the human race is at risk as long as it is confined to a single planet. Sooner or later, disasters such as an asteroid collision or nuclear war could wipe us all out. But once we spread out into space and establish independent colonies, our future should be safe. There isn't anywhere like the Earth in the solar system, so we would have to go to another star."
-- Stephen Hawking, Physicist

"By 2025 we expect new spacecraft designed for long journeys to allow us to begin the first ever crewed missions beyond the Moon into deep space. So we’ll start by sending astronauts to an asteroid for the first time in history. By the mid-2030s I believe we can send humans to orbit Mars and return them safely to Earth. And a landing on Mars will follow and I expect to be around in see it."
--President Barack Obama, Cape Canaveral, Florida. Speech outlining his administration's space policy, 15 April 2010.

"We'll build new ships to carry man forward into the universe, to gain a new foothold on the Moon and to prepare for new journeys to the worlds beyond our own. . . . We do not know where this journey will end, yet we know this: human beings are headed into the cosmos."
-- President George W. Bush, speech at NASA headquarters, 14 January 2004

"All civilizations become either spacefaring or extinct."
-- Carl Sagan, Astronomer


First Super-Earths Discovered Orbiting Sun-Like Stars

SOURCE: Science Daily
Dec. 14, 2009

An international team of planet hunters has discovered as many as six low-mass planets around two nearby Sun-like stars, including two "super-Earths" with masses 5 and 7.5 times the mass of Earth. The researchers, led by Steven Vogt of the University of California, Santa Cruz, and Paul Butler of the Carnegie Institution of Washington, said the two "super-Earths" are the first ones found around Sun-like stars.

"These detections indicate that low-mass planets are quite common around nearby stars. The discovery of potentially habitable nearby worlds may be just a few years away," said Vogt, a professor of astronomy and astrophysics at UCSC.

The team found the new planet systems by combining data gathered at the W. M. Keck Observatory in Hawaii and the Anglo-Australian Telescope (AAT) in New South Wales, Australia. Two papers describing the new planets have been accepted for publication in the Astrophysical Journal.

Three of the new planets orbit the bright star 61 Virginis, which can be seen with the naked eye under dark skies in the Spring constellation Virgo. Astronomers and astrobiologists have long been fascinated with this particular star, which is only 28 light-years away. Among hundreds of our nearest stellar neighbors, 61 Vir stands out as being the most nearly similar to the Sun in terms of age, mass, and other essential properties. Vogt and his collaborators have found that 61 Vir hosts at least three planets, with masses ranging from about 5 to 25 times the mass of Earth.

Recently, a separate team of astronomers used NASA's Spitzer Space Telescope to discover that 61 Vir also contains a thick ring of dust at a distance roughly twice as far from 61 Vir as Pluto is from our Sun. The dust is apparently created by collisions of comet-like bodies in the cold outer reaches of the system.

Read More:
For more information:

Super-Earths Orbit Neighboring Stars
Super-Earths found orbiting nearby stars
Super-Earths Found Around Sun-Like Stars


Astronomers find 'super Earth' around another star; call it Rocky

SOURCE: The Christian Science Monitor
September 16, 2009

Quick! Before you begin reading, drop down to the bottom of the post, activate the YouTube link, then quickly scroll back up here (all you really need is the sound).

Laydeeezzz and gentlemun, boyzzz and girlzzz, an international team of astronomers on the Third Rock from the sun gives you the best evidence yet for a rocky planet -- not too much bigger than Earth -- orbiting another star.

The planet is called CoRoT-7b. And it appears to have a sibling super-Earth, CoRoT-7c, though much less is known about it. This makes the system the first dual super-Earth system astronomers have found. The team summarized its findings today at the European Planetary Science Congress, meeting this week in Postdam, Germany.

You can find a lay-language summary here. You can find a PDF of the formal results, accepted for publication in the journal Astronomy and Astrophysics, here.

CoRoT-7b is the smallest exoplanet found so far. It's slightly more than 1.5 times as large as Earth. But any vague resemblance stops there.

The parent star -- 500 light-years away in the constellation Monoceros -- is some 1.5 billion years old. The planet orbits its star at a distance of less then 2 million miles, giving it a "year" that lasts about 20 hours.

With an orbit that close, the team estimates that the temperatures on the planet's surface range somewhere between 1,527 to 2,327 degrees Celsius on the sunlit portion (think molten on the surface) and a frosty -200 degrees C on the night portion.

Read More:

First rocky planet found outside solar system


Kepler Spacecraft

NASA's Kepler spacecraft has begun its search for other Earth-like worlds. The mission, which launched from Cape Canaveral on March 6 2009, will spend the next three-and-a-half years staring at more than 100,000 stars for telltale signs of planets. Kepler has the unique ability to find planets as small as Earth that orbit sun-like stars at distances where temperatures are right for possible lakes and oceans.

For more information:

New space telescope to search for earth-sized planets
Planet-Hunting Spacecraft Beams Home First Images
Telescope can find "oodles" of Earths: NASA
Kepler spacecraft sees its first exoplanets
Kepler Detects an Exoplanet Atmosphere
Spacecraft blasts off in search of 'Earths'
Nasa launches search for second Earth
The Inspiring Boom in "Super-Earths"
Let the Planet Hunt Begin
Kepler Spacecraft
Kepler works!


Galaxy has 'billions of Earths'

15 February 2009

There could be one hundred billion Earth-like planets in our galaxy, a US conference has heard.

Dr Alan Boss of the Carnegie Institution of Science said many of these worlds could be inhabited by simple lifeforms.

He was speaking at the annual meeting of the American Association for the Advancement of Science in Chicago.

So far, telescopes have been able to detect just over 300 planets outside our Solar System.

Very few of these would be capable of supporting life, however. Most are gas giants like our Jupiter, and many orbit so close to their parent stars that any microbes would have to survive roasting temperatures.

But, based on the limited numbers of planets found so far, Dr Boss has estimated that each Sun-like star has on average one "Earth-like" planet.

This simple calculation means there would be huge numbers capable of supporting life.

"Not only are they probably habitable but they probably are also going to be inhabited," Dr Boss told BBC News. "But I think that most likely the nearby 'Earths' are going to be inhabited with things which are perhaps more common to what Earth was like three or four billion years ago." That means bacterial lifeforms.

Dr Boss estimates that Nasa's Kepler mission, due for launch in March, should begin finding some of these Earth-like planets within the next few years.

Recent work at Edinburgh University tried to quantify how many intelligent civilisations might be out there. The research suggested there could be thousands of them.

This article:
For more information:

The Milky Way Could have Billions of Earths
Galaxy may be full of 'Earths,' alien life


Telescope sees smallest exoplanet

3 February 2009

The smallest planet yet found outside the Solar System has been detected by a French space telescope.

The rocky world is less than twice the size of Earth.

Only a handful of planets have so far been found with a mass comparable to Earth, Venus, Mars or Mercury.

The discovery was made by Corot, an orbiting observatory with a 27cm-diameter telescope to search for planets orbiting other stars.

About 330 of these "exoplanets" have been discovered so far. But most of them have been gas giants similar to Jupiter or Neptune.

"For the first time, we have unambiguously detected a planet that is 'rocky' in the same sense as our own Earth," said Malcolm Fridlund, Corot project scientist from the European Space Agency (Esa).

"We now have to understand this object further to put it into context, and continue our search for smaller, more Earth-like objects with Corot," he added.

The new find, Corot-Exo-7b, orbits its Sun-like star once every 20 hours. Although very close to Earth in terms of width, its mass is several times that of our own planet.

Because the planet is so close to its parent star, its temperature is between 1,000 and 1,500C - far too hot to support life.

Read More:


Rocky Planets May Form Around Most Sun-like Stars

SOURCE: Universe Today
Feb 18 2008

Astronomers have found numerous Jupiter-like planets orbiting other stars. But because of the limits of our current technology, they haven̢۪t yet found any other terrestrial Earth-like planets out in the universe. But new findings from the Spitzer Space Telescope suggest that terrestrial planets might form around many, if not most, of the nearby sun-like stars in our galaxy. So perhaps, other worlds with the potential for life might be more common than we thought.

A group of astronomers led by Michael Meyer of the University of Tucson, Arizona used Spitzer to survey six sets of stars with masses comparable to our sun, and grouped them by age. "We wanted to study the evolution of the gas and dust around stars similar to the sun and compare the results with what we think the solar system looked like at earlier stages during its evolution," Meyer said. Our sun is about 4.6 billion years old.

They found that at least 20 percent, and possibly as many as 60 percent, of stars similar to the sun are candidates for forming rocky planets.

Read More:

Planet-hunters set for big bounty


Astronomers search for habitable moons

Source: National Geographic

September 2, 2009--A Jupiterlike planet peeks through the clouds above a so-called exomoon in an artist's rendering. It's possible that NASA's planet-hunting satellite Kepler, launched earlier this year, will find habitable moons as well as Earthlike worlds, astronomers announced this week.

Kepler looks for planets outside our solar system by searching for periodic dips in the brightnesses of distant stars, thought to be due to orbiting planets crossing the faces of the stars.

Now a new model suggests that the probe could also look for changes in the speed and position of a transiting planet caused by the gravitational tug of a moon. Knowing the host planet's size, mass, and distance from its star would then reveal whether the moon might be able to support liquid water, and thus life.

For more information:

Habitable moons could to be spotted by 2014
Scientists devise method to detect exomoons
Astronomers search for habitable moons
Planet wobbles could reveal Earth 2.0
Planet-hunter will find alien moons
Search for life elsewhere expands
How to spot moons far, far away
Detecting Life-Friendly Moons
Habitable Moons
And more

Artist’s impression of a hypothetical exomoon in orbit around a Saturn-like planet in another planetary system. (Click image to enlarge)

New Video Sees Earth from Alien Perspective

18 July 2008

NASA's Deep Impact spacecraft has made a movie of the moon passing in front of the Earth from the probe's vantage point millions of miles away.

Astronomers plan to use the video to develop techniques to look for Earth-like worlds in other solar systems.

"Making a video of Earth from so far away helps the search for other life-bearing planets in the universe by giving insights into how a distant, Earth-like alien world would appear to us," said Michael A'Hearn of the University of Maryland and the principal investigator for the Deep Impact extended mission.

Deep Impact, which sent an impactor into comet Tempel 1 on July 4, 2005, is currently 31 million miles away from Earth on its way to a flyby of comet Hartley 2 on Nov. 4, 2010.

During its cruise to Hartley 2, Deep Impact will be searching for extrasolar planets.

Read More:

What would Earth look like to alien astronomers? See Video!

Trio of 'super-Earths' discovered orbiting one star

June 16, 2008

Artist's impression of the trio of super-Earths discovered using the ESO's 3.6-m telescope at La Silla, Chile, after five years of monitoring. The three planets, having 4.2, 6.7, and 9.4 times the mass of the Earth, orbit the star HD 40307 with periods of 4.3, 9.6, and 20.4 days, respectively. (ESO)

European astronomers said Monday they have discovered five "super-Earths" — including three orbiting a single star — which they say suggests Earth-like planets could be very common outside our solar system.

The discoveries, revealed at a conference in France, were made using a spectrograph at the La Silla Observatory in Chile, which is run by the European Organization for Astronomical Research in the Southern Hemisphere, or ESO.

Planet hunter Michel Mayor, best known for discovering the first confirmed planet outside our solar system, said in a statement the finds suggest the search for Earth-like planets has just begun.

Read More:

For more information:
  1. Three "Super-Earths" Found Orbiting Sun-Like Star
  2. Three Super-Earths Found Orbiting One Star
  3. Three super-Earths found around one star

New rocky planet found in constellation Leo

April 9, 2008

Spanish and UCL (University College London) scientists have discovered a possible terrestrial-type planet orbiting a star in the constellation of Leo. The new planet, which lies at a distance of 30 light years from the Earth, has a mass five times that of our planet but is the smallest found to date. One full day on the new planet would be equivalent to three weeks on Earth.

The team of astronomers from the Spanish Research Council (CSIC) working with Dr Jean-Philippe Beaulieu, a visiting astrophysicist at UCL, made the discovery from model predictions of a new exoplanet (meaning planet outside our solar system) orbiting a star in the constellation of Leo.

Simulations show that the exoplanet, dubbed GJ 436c, orbits its host star (GJ 436) in only 5.2 Earth days, and is thought to complete a revolution in 4.2 Earth days, compared to the Earth’s revolution of 24 hours and full orbit of 365 days. On Earth, a full day (sunset to sunset) coincides quite closely with the rotation period. On the new planet these two periods do not coincide, since the orbital translation period and the rotation period are very similar. For this reason, a full day on the new planet would take four planetary years, or roughly 22 Earth days.

The study, published this week in Astrophysical Journal, predicted the presence of a small exoplanet perturbing an inner planet (already known), producing changes on its orbit. A re-analysis of archival radial velocities also permitted the identification of a signal that perfectly matches the simulations and corresponds to a planet in resonance with the inner one, meaning that for every two orbits of the known planet the new planet completes one.

Ignasi Ribas, lead author of the study from CSIC, says: “After final confirmation, the new exoplanet will be the smallest found to date. It is the first one to be identified from the perturbations exerted on another planet of the system. Because of this, the study opens a new path that should lead to the discovery of even smaller planets in the near future, with the goal of eventually finding worlds more and more similar to the Earth.”

Dr Jean-Philippe Beaulieu, visiting astrophysicist at UCL Physics and Astronomy, says: “This is the fourth super-Earth planet discovered. This planet is the hot twin of the frozen super-Earth (OGLE-2005-BLG-390lb) we discovered by microlensing two years ago. Other previously discovered planets of this class are the two hot super-Earths Gl 581b and Gl 876d detected by their Doppler wobble.“

Dr Giovanna Tinetti, UCL Physics and Astronomy who recently calculated the putative properties of this planet, says: “Calculations indicate that the temperature of the planet could be within 400-700 Kelvin [127-427 Celsius], but it could locally be as low as 350 K [77 C] at the poles, depending on the type of atmosphere.”

Most of the 280 or so planets discovered to date are gas giants similar to Jupiter, although some with masses below 10 times that of the Earth have already been found. Planets with masses of between one and 10 times the Earth are often dubbed super-Earths. In this case, current models predict that the new planet is a rocky type and has a radius some 50 per cent larger than the Earth.

Source: University College London

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For more information Small Earth-like Planet Discovered


MIT aims to search for Earth-like planets with Google's help

March 19, 2008

MIT scientists are designing a satellite-based observatory that they say could for the first time provide a sensitive survey of the entire sky to search for planets outside the solar system that appear to cross in front of bright stars. The system could rapidly discover hundreds of planets similar to the Earth.

Google, the Internet search powerhouse that in recent years has expanded to include mapping of the stars as well as the surfaces of the moon and Mars and which has an ongoing collaboration with NASA's Ames Research Center, provided a small seed grant to fund development of the wide-field digital cameras needed for the satellite. Because of the huge amount of data that will be generated by the satellite, Google has an interest in working on the development of ways of sifting through that data to find useful information.

Dubbed the Transiting Exoplanet Survey Satellite (TESS), the satellite could potentially be launched in 2012. "Decades, or even centuries after the TESS survey is completed, the new planetary systems it discovers will continue to be studied because they are both nearby and bright," says George R. Ricker, senior research scientist at the Kavli Institute for Astrophysics and Space Research at MIT and leader of the project. "In fact, when starships transporting colonists first depart the solar system, they may well be headed toward a TESS-discovered planet as their new home."

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Google Joins MIT in Search for Earth-like Planets


Extrasolar Planet Art Gallery

Here are some art pictures of extrasolar planets or exoplanets and other worlds beyond our solar system. Click the images for larger pictures.

Weird Worlds
Gallery — Strangest Alien Planets
What is an Extrasolar Planet?, click here & here.