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We have heard a lot about exoplanets in the past year. But for all the talk about these planets, which orbit a star other than our sun, we still haven't actually seen one. One tool could change that, giving us our first look at a distant planet that could be the next best thing to Earth. Currently, scientists detect an extra-solar planet by measuring the dimming of its star as the planet passes between it and our line of sight (this is known as the Transit Method). By observing the way the star's light shines around the planet, it's possible...

Earth's flora is responsible for the glaciers and rivers that have created this planet's distinctive landscapeAstronomers are finding lots of exoplanets that are orbiting stars like the sun, significantly raising the odds that we will find a similar world. But if we do, the chance that the surface of that planet will look like ours is very small, thanks to an unlikely culprit: plants. We all know how Earth's landscape came about, right? Oceans and land masses formed, mountains rose, and precipitation washed over its surface; rivers weathered bare rock to create soil and plants took root. Well, new research...

BOSTON—The number of Earth-like extrasolar planets suitable for harboring advanced life could be 10 times higher than has been assumed until now, according to a new modeling study. The finding contradicts the prevailing notion that a terrestrial planet needs a large moon to stabilize the orientation of its axis and, hence, its climate. In 1993, French mathematicians Jacques Laskar and Philippe Robutel showed that Earth’s large moon has a stabilizing effect on our planet’s climate. Without the moon, gravitational perturbations from other planets, notably nearby Venus and massive Jupiter, would greatly disturb Earth’s axial tilt, with vast consequences for the...

Forests might be detectable on extrasolar planetsThanks to a new remote sensing technique, astronomers may soon be able to detect the presence of multicellular life (like trees) on planets outside of the Solar System. Excitingly, we've been able to detect the composition of atmospheres on a handful of planets orbiting other stars. But if next-generation space observatories go online within the next couple of decades, some scientists propose using a new technique to determine details such as tree-like multicellular life on extrasolar planets. While previous studies have discussed the likelihood of detecting life on exoplanets through signs of biogenic gases...

NASA announced some preliminary results of studies by its Kepler probe on June 15: the probe's camera chips had pointed out 706 potential planets in its first 43 days of operation. Though NASA has been issuing cautionary comments, this is thrilling. These are in addition to five planets that were announced earlier by the project, places where life seems extremely unlikely.

The race to find exoplanets — planets outside our solar system — continues to quicken. Last week NASA researchers announced that the agency’s new space telescope, Kepler, has discovered five new exoplanets, expanding the number of known exoplanets to 422, an increase of about 25 percent in the past year alone. A satellite proposed by MIT researchers could accelerate these discoveries and even detect hundreds of Earth-sized planets — a few of which could be natural candidates for life.

WASHINGTON – 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...

(CNN) -- Astronomers announced this week they found a water-rich and relatively nearby planet that's similar in size to Earth. While the planet probably has too thick of an atmosphere and is too hot to support life similar to that found on Earth, the discovery is being heralded as a major breakthrough in humanity's search for life on other planets. "The big excitement is that we have found a watery world orbiting a very nearby and very small star," said David Charbonneau, a Harvard professor of astronomy and lead author of an article on the discovery, which appeared this...

Today, at an international ESO/CAUP exoplanet conference in Porto, the team who built the High Accuracy Radial Velocity Planet Searcher, better known as HARPS, the spectrograph for ESO's 3.6-metre telescope, reports on the incredible discovery of some 32 new exoplanets, cementing HARPS's position as the world’s foremost exoplanet hunter. This result also increases the number of known low-mass planets by an impressive 30%. Over the past five years HARPS has spotted more than 75 of the roughly 400 or so exoplanets now known.

Enlarge ImageEbb tide. A planet the size of Earth can be lifeless if tidal forces are strong enough to roil its interior. Credit: P. Marenfeld/NOAO/AURA/NSF Astronomers scanning the skies for another Earth might need to narrow their search. New research suggests that even if a world lies within the Habitable Zone, in which water is liquid, too much or too little volcanic activity can render it lifeless. When assessing a distant planet's habitability, astronomers currently focus on one main criterion: Could the planet have liquid water on its surface? Too close to its sun, and that water evaporates away;...

Lunar eclipse paints portrait of Earth that could aid hunt for distant habitable planets.The rosy glow of a lunar eclipse helped astronomers capture the Earth's transmission spectrum.Daniel Lopez Astronomers have seen what the Earth's atmosphere might look like from outer space by using the Moon as a giant mirror. Sunlight that bounced back from the Moon carried a fingerprint of the Earth's atmosphere that could help astronomers determine if the extrasolar planets they're finding harbour life.The astronomers, at Spain's Institute of Astrophysics of the Canary Islands, made their observations on 16 August 2008 during a lunar eclipse — in which...

A Europan Scenario Between living dirigibles on gas giants and potential organisms under the ice, we’ve had quite a week in terms of exotic life-forms. I didn’t have space in yesterday’s review of Unmasking Europa to talk about the book’s chapter on biology, but here’s an interesting glimpse of a not implausible biosphere on that moon, as presented by physicist Richard Greenberg:

Next week brings a milestone in the search for extraterrestrial life with the scheduled launch Friday of NASA's Kepler satellite. The mission, named for 16th- and 17th-century German astronomer Johannes Kepler, will study a group of stars for three-plus years in search of subtle, periodic dips in stellar brightness—the telltale signs of planetary orbits. Although more than 300 planets outside the solar system have already been found using this method, among other techniques, Kepler's strength will lie in its instruments' sensitivity to smaller, cooler planets more hospitable to life and more like our own. In a new book, planetary scientist...

Detecting Alien Vegetation Could we find evidence of vegetation on distant exoplanets? The answer may be yes, according to recent work by Luc Arnold (Observatoire de Haute Provence) and team. If green vegetation on another planet is anything like what we have on Earth, then it will share a distinctive spectral signature called the Vegetation Red Edge, or VRE. The new paper creates climate simulations that explore whether planets with a distinctively different climate than modern Earth’s could be so detected.Two earlier eras are useful here. The Last Glacial Maximum (LGM) occurred 21,000 years ago, with global temperatures on...

Finding Terrestrial Worlds in the Dust October 13th, 2008 Computer simulations are showing us how to detect the signature of Earth-like planets — indeed, planets nearly as small as Mars — around other stars. That interesting news comes out of NASA’s Goddard Space Flight Center, where a supercomputer named Thunderbird has been put to work studying dusty disks around stars similar to the Sun. Varying the size of the dust particles along with the mass and orbital distance of the planet, the team led by Christopher Stark (University of Maryland) ran 120 different simulations. “It isn’t widely appreciated that planetary...

Researchers are racing to find the first planet that might support life as we know it.Gliese 876 is a modest star, just one-third the mass of our sun and only 15 light-years away, but it has a history-making planetary system all its own. In 1998 a team led by Geoff Marcy of the University of California at Berkeley detected the first sign of something interesting there: a giant planet, twice the mass of Jupiter, circling Gliese 876 once every two months, its gravity yanking the star back and forth at the speed of a jet plane. Three years later the...

How large a planet is depends upon its composition and mass. Earth is largely made of silicates, with a diameter of 7,926 miles at the equator. Imagine an Earth mass planet made of iron and youÂ’re looking at a diameter of a scant 3000 miles. Interestingly, the relationship between mass and diameter follows a similar pattern no matter what material makes up the planet. Running the numbers, an Earth mass planet made of pure water will be 9500 miles across. Sara Seager (Massachusetts Institute of Technology) has been studying these things as part of a project to model the kind...

The search for planets orbiting other stars, otherwise known as "exoplanets", is unearthing new discoveries at an ever increasing rate. In fact, this is one of the fastest-developing aspects of humanity's investigation of the Universe. This and other themes are explored in the Open University's new series Cosmos: A Beginner's Guide. At the last count there were at least 244 known exoplanets. More than 40 of these celestial bodies have been discovered in the first seven months of 2007 alone.

On Monday morning at the American Astronomical Society meeting in Honolulu, an international team of astronomers announced the discovery and identification of 28 new extrasolar planets. This largest-ever announcement, made by post-doctoral fellow Jason T. Wright and newly minted Ph.D. John Asher Johnson, both of the University of California-Berkeley, brings the total number of planets known outside our solar system to 236. "In the last year we've found 37 substellar objects," says Wright, "the 28 new planets constituting more than 10 percent of those now known." Wright reported that 7 of the substellar objects are thought to be brown dwarfs,...

When I was growing up in the '50s, there was a long list of things I was told never would happen. A Catholic never would be elected president, there never would be an end to the Cold War and we never would know what killed the dinosaurs. Those predictions turned out to be wrong. John F. Kennedy won the White House in 1960, the Soviet Union fell in 1991 and most scientists now agree that the dinosaurs were killed by an asteroid. However, there was still one thing I was sure I'd never live to see: evidence of life on...

Astronomers have found the most Earth-like planet outside our Solar System to date, a world which could have water running on its surface. The planet orbits the faint star Gliese 581, which is 20.5 light-years away in the constellation Libra. Scientists made the discovery using the Eso 3.6m Telescope in Chile. They say the benign temperatures on the planet mean any water there could exist in liquid form, and this raises the chances it could also harbour life. "We have estimated that the mean temperature of this 'super-Earth' lies between 0 and 40 degrees Celsius, and water would thus be...

Munich, April 24: An international team of astronomers from Switzerland, France and Portugal have discovered the most Earth-like planet outside our Solar System to date. The planet has a radius only 50 percent larger than Earth and is very likely to contain liquid water on its surface. The research team used the European Southern Observatory’s (ESO’s) 3.6-m telescope to discover the super-Earth, which has a mass about five times that of the Earth and orbits a red dwarf already known to harbour a Neptune-mass planet. Astronomers believe there is a strong possibility in the presence of a third planet with...

In the film Star Wars, Luke Skywalker gazed at a twin sunset from his desert homeworld The dual suns that rise and set over Luke Skywalker's homeworld in the film Star Wars may be more than just fantasy, according to data from Nasa.In a classic scene from the 1977 movie, the hero gazes into the distance as two yellow suns set on the horizon. Nasa's Spitzer Space Telescope has found that planetary systems are as common around double stars as they are around single stars, like our own Sun. Details of the research have been published in the Astrophysical...

This could be a banner year in the search for alien planets. Earlier this month, a new European satellite began its mission to spot planets as they orbit in front of their stars. Meanwhile, a research team has demonstrated the power of that technique by using Hubble Space Telescope data to trace activity in the outer atmosphere of an alien world. It's the first time such meteorological details have been gathered from a planet in another star system. Astronomers have found 209 "exoplanets," the name they give to alien worlds. More could be reported at any time. Observers have found...

One half of the camera is designed to look for planets; the other half is optimised to detect the subtle variation in a star’s light, caused by sound waves rippling across the surface. These waves are the equivalent of seismic waves on the Earth... The technique is known as asteroseismology. ESA’s Solar and Heliospheric Observatory (SOHO) has been pioneering similar investigations of the Sun for many years. It has proved to be an extremely successful way to probe the internal conditions of a star and astronomers are eager to extend the technique to other stars. COROT will target at least...

Newswise — The steady discovery of giant planets orbiting stars other than our sun has heightened speculation that there could be Earth-type worlds in nearby planetary systems capable of sustaining life. Now researchers running computer simulations for four nearby systems that contain giant planets about the size of Jupiter have found one that could have formed an Earth-like planet with the right conditions to support life. A second system is likely to have a belt of rocky bodies the size of Mars or smaller. The other two, the models show, do not have the proper conditions to form an Earth-size...

A FIFTH terrestrial planet may once have orbited between Mars and Jupiter. Although gravitational disturbances would have sent the planet hurtling into the sun or out into space long ago, traces of this long-gone world may still be visible in part of the asteroid belt today. Recent simulations have suggested that the gas giants of our solar system formed with circular orbits but moved into their more elongated paths about 4 billion years ago – 700 million years after the solar system formed. While the gas giants were in circular orbits, rocky planets should have formed in stable orbits out...

Habitable, Earth-like planets can form even after giant planets have barrelled through their birthplace on epic migrations towards their host stars, new computer simulations suggest. The finding contradicts early ideas of how planets behave and suggests future space missions should search for terrestrial planets near known "hot Jupiters". Many of the 160 or so known extrasolar planets are hot Jupiters - massive planets that are closer to their stars than Mercury is to our Sun. But the planets probably did not form in these scorching regions because there would not have been enough gas and dust there to amass such...

NASA Announces Spitzer Planet Finder Update Astronomers using NASA's Spitzer Space Telescope will hold a media teleconference at 1 p.m. EDT Wednesday, April 5 to announce the discovery of a strange place where planets might be forming.

Marc Kuchner at Goddard Space Flight Center is aiming to attack a question that has puzzled us since we first peered into the heavens: Are we alone in the universe? Kuchner came to the Greenbelt research center six months ago from Princeton to step up a search for habitable Earth-like planets outside our solar system. He is writing a proposal for NASA funding for a new space hunting probe and, over the next few years, plans to hire a staff of five or six researchers for the fledgling ExoPlanets and Stellar Astrophysics Laboratory. The size of the staff will depend...

March 14, 2006— A team of astronomers has discovered a large, ice-rock planet that dominates a distant solar system, much like Jupiter reigns in our bit of Milky Way real estate. Taking into account other discoveries of extrasolar planets, the finding of an Earth-class planet leads scientists to theorize that the type of planetary system that develops around a star depends on the size of the star.

Due for launch in 2006, Corot will be the first mission capable of detecting rocky planets outside our Solar System. This week EuroNews takes a closer look at this 30-centimetre diameter space telescope which will be able to detect tiny changes in brightness from nearby stars.

The search for alien life outside our solar system has been made a little less daunting thanks to a new list drawn up by astronomer Margaret Turnbull that includes the known stars most likely to support habitable stellar systems. Turnbull, an astronomer at the Carnegie Institute of Washington, listed 10 of what she believes are likely to be habitable stellar systems, or “habstars,” capable of supporting Earth-like planets and life. The list was presented at the recent annual meeting of the American Association for the Advancement of Science in St. Louis. Five of the stars on the list are thought...

ST. LOUIS - An astronomer involved in a NASA mission to look for Earthlike planets beyond our solar system has winnowed through thousands of stars to come up with a top-10 list that includes some of the favorite haunts for science-fiction aliens. Actually, the lineup from Margaret Turnbull at the Carnegie Institute of Washington is broken down into two top-five lists: one for the radio-based search for extraterrestrial intelligence, or SETI, and the other for the NASA mission, known as the Terrestrial Planet Finder. The SETI stars will be on the list of targets for the privately funded Allen Telescope...

In the search for life on other worlds, scientists can listen for radio transmissions from stellar neighborhoods where intelligent civilizations might lurk or they can try to actually spot planets like our own in habitable zones around nearby stars. Either approach is tricky and relies on choosing the right targets for scrutiny out of the many thousands of nearby stars in our galactic neighborhood. Margaret Turnbull, an astronomer at the Carnegie Institution of Washington, has devoted herself to the painstaking search for candidate stars that may harbor zones of habitability where life--primitive or otherwise-- might thrive. Turnbull announced her shortlist...

he basic molecules of life are scattered through the universe, collecting in faraway galactic clouds, on passing comets and asteroids, and on the planets here in our solar system. But scientists still don’t know how these molecules came to be, or how they originally came together to form life. Now, for the first time ever, astronomers have found some of the basic compounds necessary to build organic molecules and proteins found in DNA within the inner regions of a planet-forming disk. “We see prebiotic organic molecules in comets and the gas giant planets in our own solar system and wonder,...

Astronomers have found a debris disk around a sun-like star that may be forming or has formed its terrestrial planets. The disk - a probable analog to our asteroid belt - may have begun a solar-system-scale demolition derby, where the rocky remains of failed planets collide chaotically. "This is one of a very rare class of objects that may give us a glimpse into what our solar system may have looked like during the formation of our terrestrial planets," said Dean C. Hines of the Space Science Institute, a leader of the team that discovered the rare objects with NASA's...

A new optical device might allow astronomers to view extrasolar planets directly without the annoying glare of the parent star. It would do this by "nulling" out the light of the parent star by exploiting its wave nature, leaving the reflected light from the nearby planet to be observed in space-based detectors. The device, called an optical vortex coronagraph, is described in the December 15, 2005 issue of Optics Letters. About ten years ago the presence of planets around stars other than our sun was first deduced by the very tiny wobble in the star's spectrum of light imposed by...

NASA's Spitzer Space Telescope has spotted the very beginnings of what might become planets around the puniest of celestial orbs - brown dwarfs, or "failed stars." The telescope's infrared eyes have for the first time detected clumps of microscopic dust grains and tiny crystals orbiting five brown dwarfs. These clumps and crystals are thought to collide and further lump together to eventually make planets. Similar materials are seen in planet-forming regions around stars and in comets, the remnants of our own solar system's construction.

A newly discovered planet has bountiful sunshine, with not one, not two, but three suns glowing in its sky. It is the first extrasolar planet found in a system with three stars. How a planet was born amidst these competing gravitational forces will be a challenge for planet formation theories. "The environment in which this planet exists is quite spectacular," said Maciej Konacki from the California Institute of Technology. "With three suns, the sky view must be out of this world -- literally and figuratively." The triple-star system, HD 188753, is located 149 light-years away in the constellation Cygnus. The...

Astronomers from across Europe today (July 7th) took a step closer to making their plans for a giant telescope a reality when they unveiled the scientific case for an Extremely Large Telescope (ELT) - a monster telescope with a light capturing mirror of between 50 and 100 metres, dwarfing all previous optical telescope facilities. The announcement was made at a meeting in Dwingeloo, the Netherlands and initiates the design phase of the project. Astronomers plan to use the ELT to search for planets like the Earth in other star systems and to find out when the first stars in the...

Two amateur New Zealand astronomers have played a central role in the discovery of one of the most distant planets ever found, using a pioneering technique that might one day find a world similar to our own. Astronomer Grant Christie, of Espom in Auckland, and a colleague from Stardome Observatory, Jennie McCormick, who built an observatory at her Pakuranga home, used telescopes plenty of serious space scientists would scoff at.

AUSTRALIAN researchers today told how they helped discover a huge planet in the Milky Way galaxy. The Tasmanian astronomers used a new scientific technique to detect the planet, renewing hopes of finding Earth-like planets.

Astronomers have found a second extrasolar planet with a technique known as gravitational microlensing. Scientists say the discovery of this new giant planet gives additional credence of this method of planet finding.

A reddish speck photographed near a dim and distant star last year is indeed a planet, about five times the mass of Jupiter, an international team of astronomers is reporting today. They say the results bolster their claim, put forward last fall, that this image was the first of a planet orbiting a star outside the solar system. The planet, about 230 light-years from Earth in the constellation Hydra, orbits a kind of failed star known as a brown dwarf at a distance of at least five billion miles, twice as far as icy Neptune is from our own Sun....

Maggie Turnbull, an astronomer with the Carnegie Institution, has spent many years thinking about what kind of stars could harbor Earth-like planets. Her database of potentially habitable star systems could be used as a target list for NASA's upcoming Terrestrial Planet Finder (TPF) mission. Turnbull presented a talk, "Remote Sensing of Life and Habitable Worlds: Habstars, Earthshine and TPF," at a NASA Forum for Astrobiology Research on March 14, 2005.

Another Jupiter Twin Found in Flood of Planet Discoveries By Robert Roy Britt Senior Science Writer and Tariq Malik Staff Writer WASHINGTON, D.C. - European astronomers announced this week the discovery of a Jupiter-like planet around another star, a finding that comes less than a week after a similar announcement of a Jovian lookalike around another star by a U.S.-led team. The latest discovery is a gas giant world similar in mass to Jupiter in an orbit at 3.7 astronomical units (AU). One AU is the distance from Earth to the Sun. Jupiter orbits at 5.2 AU. Though the discovery...