Free Republic

Astronomers announced today the discovery of at least four — and as many as six — planets orbiting two nearby stars. These planets are relatively low mass, ranging from 5 to 25 times the mass of the Earth. For comparison, Jupiter is over 300 times more massive than the Earth, and Uranus 15 times our mass. Three of these extrasolar planets orbit the nearby star 61 Virginis, which is only about 28 light years away (that’s a stone’s throw in galactic terms). 61 Vir has been a target for planet hunters for some time because it’s very much like our...

Sunlike stars that harbor planets are low on lithium, according to a recent study that may offer a new tool in the hunt for planets beyond our solar system. Stars are made almost entirely of hydrogen and helium. A small percentage of a star's mass comes from heavier elements, which astronomers refer to as metals. Young, yellow stars like our sun usually have more metals than older, redder stars, although the exact mix of those metals can vary. But astronomers have been unable to explain why otherwise similar sunlike stars have widely different lithium levels.The new study suggests that the...

Astronomers using the Science and Technology Facilities Council's (STFC) William Herschel Telescope (WHT) on La Palma have confirmed an effective way to search the atmospheres of planets for signs of life, vastly improving our chances of finding alien life outside our solar system. The team from the Instituto de Astrofisica de Canarias (IAC) used the WHT and the Nordic Optical Telescope (NOT) to gather information about the chemical composition of the Earth's atmosphere from sunlight that has passed through it. The research is published June11 in Nature. When a planet passes in front of its parent star, part of the...

If you'd asked 20 years ago the question he's heard over and over -- whether humanity will discover extraterrestrial intelligence in his lifetime -- Frank Drake would have shrugged and said, "sure." Today, the renowned astronomer, who turns 79 next month, admits the chances are slimming. "It's going to be a close call," he said. But even if Drake, professor emeritus of astronomy and astrophysics at the University of California at Santa Cruz, doesn't see the day we learn we're not alone, he knows it's coming. To him, it's a mathematical inevitability. He should know. He wrote the formula. And...

The Kepler launch is coming up on March 5, marking the first time we will have the ability to find a true Earth analogue around another star; i.e., a planet of about Earth’s mass in the habitable zone where water can exist in liquid form on the surface. Which is not to say that COROT may not come close, though Kepler’s enormous star-field (100,000 targets in the Cygnus-Lyra region) and incredibly sensitive camera — a 95-megapixel array of charged coupled devices (CCDs) — is optimized for planets down to Earth size rather than larger ’super-Earths.’ Image (click to enlarge): Kepler’s...

Alan Boss, whose new book The Crowded Universe will soon be on my shelves (and reviewed here), has driven the extrasolar planet story to the top of the news with a single statement. Speaking at the American Association for the Advancement of Science’s annual meeting in Chicago, Boss (Carnegie Institution, Washington) said that the number of Earth-like planets in the universe might be the same as the number of stars, a figure he pegged at one hundred billion trillion. A universe teeming with life? Inevitably. The Telegraph quoted Boss on the matter in an early report on his presentation: “If...

Astronomers have discovered a planet somewhat larger and more massive than Neptune orbiting a star 120 light-years from Earth. While Neptune has a diameter 3.8 times that of Earth and a mass 17 times Earth's, the new world (named HAT-P-11b) is 4.7 times the size of Earth and has 25 Earth masses. HAT-P-11b was discovered because it passes directly in front of its parent star, thereby blocking about 0.4 percent of the star's light. This periodic dimming, called a transit, was detected by a network of small, automated telescopes known as "HATNet," which is operated by the Harvard-Smithsonian Center for...

NASA's Hubble Space Telescope has taken the first visible-light snapshot of a planet circling another star. Estimated to be no more than three times Jupiter's mass, the planet, called Fomalhaut b, orbits the bright southern star Fomalhaut, located 25 light-years away in the constellation Piscis Australis, or the "Southern Fish."Fomalhaut has been a candidate for planet hunting ever since an excess of dust (a telltale sign of planet formation) was discovered around the star in the early 1980s by NASA's Infrared Astronomy Satellite, IRAS. In 2004, the coronagraph in the High Resolution Camera on Hubble's Advanced Camera for Surveys produced...

Three exoplanets orbiting the same star have been imaged directly

The idea that life on Earth might have originated elsewhere, on Mars, for example, has gained currency in recent times as we’ve learned more about the transfer of materials between planets. Mars cooled before the Earth and may well have become habitable at a time when our planet was not. There seems nothing particularly outrageous in the idea that dormant bacteria inside chunks of the Martian surface, blasted into space by comet or asteroid impacts, might have crossed the interplanetary gulf and given rise to life here. But what of an interstellar origin for life on Earth? The odds on...

Astronomers using robotic cameras - including some in Australia - say they have found 10 new planets outside our solar system, while a second team says they have found the youngest planet yet. The findings add to a growing list of more than 270 so-called extrasolar planets, they told a meeting of astronomers in Belfast, Northern Ireland. The robot team is called "SuperWASP," for Wide Area Search for Planets, and the cameras look for planets transiting, or crossing in front of, their stars. The light from the sun fades just slightly when this happens, and astronomers can extrapolate the size...

Earth Barely Big Enough for Life, Study Says Richard A. Lovett for National Geographic News January 10, 2008 Astronomers searching for habitable worlds might do best to look for rocky planets several times larger than Earth. That's because, according to a new study, our planet is at the lower end of the size range needed for plate tectonics—which scientists believe are vital for stabilizing temperatures enough for life. Tectonics—the continent-shifting forces that build mountains and fuel volcanoes—recycle Earth's crust by drawing it underground, where it melts and later re-emerges as magma, pointed out Diana Valencia of Harvard University. That helps...

For the first time, the scattered light from a planet orbiting a distant star has been detected by an international team of astronomers led by Prof. Svetlana Berdyugina (ETH Zurich). Similar to how polaroid sunglasses filter away reflected sunlight to reduce glare, the scientists have used tricks with polarized light to enhance the faint reflected starlight "glare" from an extrasolar planet. This allowed them to trace directly the orbit of the planet and infer the size of its swollen atmosphere, in contrast to other exoplanets detected by various indirect methods. The exoplanet circles a red dwarf star, called HD189733, in...

WASHINGTON (Reuters) - Small, rocky planets that could resemble the Earth or Mars may be forming around a star in the Pleiades star cluster, astronomers reported on Wednesday. One of the stars in the cluster, also known as the Seven Sisters, is surrounded by an extraordinary number of hot dust particles that could be the "building blocks of planets" said Inseok Song, a staff scientist at NASA's Spitzer Science Center at the California Institute of Technology. "This is the first clear evidence for planet formation in the Pleiades, and the results we are presenting may well be the first observational...

WASHINGTON (Reuters) - NASA scientists said they discovered a fifth planet orbiting a star outside our own solar system and say the discovery suggests there are many solar systems that are, just like our own, packed with planets. The new planet is much bigger than Earth, but is a similar distance away from its sun, a star known as 55 Cancri, the astronomers said on Tuesday. Four planets had already been seen around the star, but the discovery marks the first time as many as five planets have been found orbiting a solar system outside our own with its eight...

This is a pic i took of Mars with a 6 mega pixel Kodak digital camera in my back yard. Its not a telescope view but it goes ta show how close Mars actualy is this year to Earth. I have a friend who has a nice telescope and we can see the ice caps and crators on Mars like looking at the moon, but have no way to hook a camera up to it.

It’s that time of year on Uranus — time for the semiannual ring-plane crossing, when the planet’s ring system appears edge-on to observers on Earth. (Unlike the other planets, Uranus spins on its side, making for extreme changes in viewing angles.) The crossing allows telescopes to take pictures of the rings from the unlighted side, free from the glare that can obscure faint parts of them. Of course, a year on Uranus is equivalent to 84 Earth years, so this semiannual event is happening for the first time since the planet’s rings were discovered, in 1977. And it’s causing some...

Pluto has suffered yet another blow to its status. Not only has it been demoted from planet to "dwarf planet", research now shows that it cannot even lay claim to being the biggest of these. A study has confirmed that the dwarf planet Eris - whose discovery prompted Pluto's relegation from planet to dwarf - outranks it in mass. snip

HONOLULU — Astronomers have discovered 28 new planets outside of our solar system, increasing to 236 the number of known exoplanets, revealing that planets can exist around a broad spectrum of stellar types, from tiny, dim stars to giants.An artist's concept of the Neptune-sized planet GJ436b (right) orbiting the M-class dwarf star Gliese 436 at a distance of 3 million miles.

Earth-like Planet Discovered by David H. Rogstad, April 25, 2007 © 2007 Reasons To Believe The news media is abuzz with the recent discovery of a new exoplanet (planet orbiting a star other than our Sun). It is the most Earth-like of any of the more than 200 planets detected so far (see here for a catalogue). The European team of astronomers responsible for this work (press release) has reported: on two new planets orbiting the M-type dwarf star Gl 581 in Libra a third body, a larger Neptune-sized planet (at least 16 times the mass of the Earth) had...

Interesting discussion with astronomer about the new planet. Listen to your local station or online --- http://www.coasttocoastam.com/

Stars incubating developing planets would do best to stay at least 1.6 light years away from very massive stellar neighbours. If they venture any closer than this, they risk having the raw materials needed for planet formation blown away from them, a new study says. Previous studies have shown that radiation from very massive stars can evaporate the planet-forming discs of gas and dust around other nearby stars. But the exact size of the 'danger zone' around massive stars was not known. Now, Zoltan Balog of the University of Arizona in Tucson, US, and colleagues have used NASA's Spitzer Space...

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...

A mysterious giant hexagon lies above Saturn's north pole, captured by cameras on Nasa's Cassini Orbiter. Spanning 25,000km - equivalent to the width of two planet Earths - the bizarre geometric feature appears to remain virtually still in the atmosphere as clouds swirl around it. The infra-red images show the hexagon - which contains a smaller six-sided formation - extends about 60km down into the clouds. The hexagon is similar to Earth's polar vortex, which has winds blowing in a circular pattern around the polar region. On Saturn, the vortex has a hexagonal shape. The six-sided shape is in stark...

Nasa release on the topography of the south polar region of Mars Scientists studying pictures from Nasa's Odyssey spacecraft have spotted what they think may be seven caves on the surface of Mars.The candidate caves are on the flanks of the Arsia Mons volcano and are of sufficient depth their floors mostly cannot be seen through the opening. Details were presented here at the Lunar and Planetary Science Conference in Houston, Texas. Temperature data from Mars Odyssey's Themis instrument support the idea. The authors say that the possible discovery of caves on the Red Planet is significant. The caves...

The Cassini radar image (left) shows one of Titan's seas is larger than Lake Superior (right) Nasa's Cassini probe has found evidence for seas, probably filled with liquid hydrocarbons, at the high northern latitudes of Saturn's moon Titan.The dark features, detected by Cassini's radar, are much bigger than any lakes already detected on Titan. The largest is some 100,000 sq km (39,000 sq miles) - greater in extent than North America's Lake Superior. It covers a greater fraction of Titan than the proportion of Earth covered by the Black Sea. The Black Sea is the Earth's largest inland sea...

What should follow the great success of Cassini-Huygens? The European and US space agencies are moving ahead on their next major missions to explore the Solar System. Nasa has begun choosing a destination for a "flagship" robotic venture along the lines of Cassini-Huygens, which has been exploring Saturn and its moons. It is considering four targets: the Jupiter system, Jupiter's moon Europa, and Saturn's moons Enceladus and Titan. The European Space Agency has called for proposals for one flagship mission and another medium-sized mission. Europa, Titan and Enceladus are also among the destinations expected to be proposed under the...

Alien Light: Taking the spectra of extrasolar planets Ron Cowen Astronomers have for the first time recorded the spectra of light emitted by two extrasolar planets. This achievement provides a new, direct way to analyze the atmosphere of alien worlds light-years from Earth. OBSCURED ORB. Clouds may sheathe the atmosphere of some extrasolar planets, masking the presence of water vapor at lower altitudes, as in this artist's depiction. JPL-Caltech/NASA Obtained by NASA's Spitzer Space Telescope, the infrared spectra represent a milestone in the study of distant planets, says David Charbonneau of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. Both...

WASHINGTON - Scientists taking their first "sniffs of air" from planets outside our solar system are a bit baffled by what they didn't find: water. One of the more basic assumptions of astronomy is that the two distant, hot gaseous planets they examined must contain water in their atmospheres. The two suns the planets orbit closely have hydrogen and oxygen, the stable building blocks of water. These planets' atmospheres — examined for the first time using light spectra to determine the air's chemical composition — are supposed to be made up of the same thing, good old H2O. But when...

NASA Media Teleconference on Planets Beyond Our Solar System PASADENA, Calif. - Astronomers are scheduled to announce new findings about planets beyond our solar system at a media teleconference Wednesday, Feb. 21, at 10 a.m. PST. The findings are from NASA's Spitzer Space Telescope. Reporters should call the media relations office at NASA's Jet Propulsion Laboratory, Pasadena, Calif., at 818-354-5011 for participation information. Audio of the event will be broadcast live at 1 p.m. on the Web at:

A planet-hunting satellite that launched in December has opened its eye to the stars. Its first images suggest the satellite's instruments are in good working order, paving the way for planet searching to begin in February. The mission, called Convection Rotation and planetary Transits (COROT) and led by France's Centre Nationale d'Etudes Spatiales (CNES), launched on 27 December from the Baikonur cosmodrome in Kazakhstan (see Planet-finding telescope blasts off). It will use a 27-centimetre telescope to look for the tiny brightness dips of stars caused by planets passing in front of them, potentially spotting planets just two or three times...

We must stop the U.S. Administration from foisting this disastrous anti-science, antiexploration agenda on NASA. I want to help the Society fend off these attacks that are threatening both space science and human and robotic exploration of other worlds. PETITION TO PRESIDENT GEORGE W. BUSH Your administration's proposal to cut the budget for NASA's Space Science and exploration programs will inflict long-term, possibly irreparable, harm to the future of space exploration. Your own Vision for Space Exploration is being distorted. This budget, if passed, threatens to cancel decades of vital exploration, the very thing that gains the United States international...

An infrequent astronomical sight — tiny Mercury inching across the surface of the sun — takes place Wednesday afternoon in North America. But you'll need the right kind of telescope to see it.

Astronomers have discovered a new class of planets that take less than a day to whiz round their parent stars. Observations with the Hubble Space Telescope revealed the existence of the planets, which orbit closer to their stars than any previously known. Dr Kailash Sahu and colleagues report finding the planets in a faint, crowded star field in a region of the Milky Way known as the Galactic bulge. The team has published its findings in the scientific journal Nature. They uncovered the existence of 16 planets in the category of close orbiters, taking between 0.4 and 3.2 days...

Astronomers have discovered two new planets outside our solar system, both extremely close to their stars and thus among the hottest ever found. A University of Florida astronomer is among more than three dozen astronomers who found the new large planets, announced today at the Transiting Extrasolar Planets Workshop at the Max Planck Institute for Astronomy in Heidelberg, Germany. Stephen Kane, a UF postdoctoral associate, said he and his colleagues pinpointed the planets by detecting the slight dimming of starlight that occurs when the planets pass in front of their stars. Of about 200 planets discovered so far, the new...

GREENBELT, Md.: The odds of finding another temperate, Earth-like planet beyond our galaxy may be “significantly higher” than earlier thought, a new study has suggested. Scientists at NASA's Astrobiology Institute said it is more likely to find a planet covered with deep oceans and providing conditions that can sustain life, conditions similar to our own planet. The researchers had focused on the behavior of giant gas planets called 'Hot Jupiters' which are known to orbit very close to their parent. Such gas giants were also observed to plow through any stellar material in its path often creating a “habitable zone”...

WASHINGTON (Reuters) - Earthlike planets covered with deep oceans that could harbor life may be found in as many as a third of solar systems discovered outside of our own, U.S. researchers said on Thursday. These solar systems feature gas giants known as "Hot Jupiters," which orbit extremely close to their parent stars -- even closer than Mercury to our sun, University of Colorado researcher Sean Raymond said. The close-orbiting gassy planets may help encourage the formations of smaller, rocky, Earthlike planets, they reported in the journal Science. "We now think there is a new class of ocean-covered, and possibly...

Astronomers using NASA's Hubble Space Telescope have photographed one of the smallest objects ever seen around a normal star beyond our Sun. Weighing in at 12 times the mass of Jupiter, the object is small enough to be a planet. The conundrum is that it's also large enough to be a brown dwarf, a failed star.

Pluto got its walking papers yesterday. Throw away the place mats. Redraw the classroom charts. Take a pair of scissors to the solar system mobile. After years of wrangling and a week of debate, astronomers voted for a sweeping reclassification of the solar system. In what many of them described as a triumph of science over sentiment, Pluto was demoted to the status of a “dwarf planet.” In the new solar system as defined by the International Astronomical Union, meeting in Prague, there are eight planets instead of nine, at least three dwarf planets and tens of thousands of so-called...

PRAGUE, Czech Republic - Leading astronomers declared Thursday that Pluto is no longer a planet under historic new guidelines that downsize the solar system from nine planets to eight. After a tumultuous week of clashing over the essence of the cosmos, the International Astronomical Union stripped Pluto of the planetary status it has held since its discovery in 1930. The new definition of what is — and isn't — a planet fills a centuries-old black hole for scientists who have labored since Copernicus without one. Although astronomers applauded after the vote, Jocelyn Bell Burnell — a specialist in neutron stars...

only 8 planets now in the solar system

The original definition of planet is wanderer, from the Greeks who watched these bright lights wander through the firmament of fixed stars. Observers discerned nine of these travelers over the course of human history, the last being Pluto in 1930. But recent discoveries of more objects orbiting the sun, both bigger than Pluto and similarly rounded in shape, called into question the arbitrary limit of nine, with some proposing that Pluto did not merit its planetary status. Now the International Astronomical Union (IAU) has crafted a new definition for what constitutes a planet that would expand the solar system to...

ASSOCIATED PRESS PRAGUE, Czech Republic -- Scientists have to agree on a universal definition for what qualifies as a planet, the head of a global astronomy organization said Tuesday, as scientists debate the future designation of Pluto. "People have to be able to agree on a terminology that's used to describe things in the universe," Ronald D. Ekers, president of the International Astronomical Union, told reporters in Prague. "We don't want an American version, a European version and a Japanese version." Ekers made his comments on the sidelines of a meeting of nearly 2,500 astronomers from 75 countries. During the...

A pair of strange new worlds that blur the boundaries between planets and stars have been discovered beyond our Solar System. A few dozen such objects have been identified in recent years but this is the first set of "twins". Dubbed "planemos", they circle each other rather than orbiting a star.

  Double vortex at Venus South pole     ESA’s Venus Express data undoubtedly confirm for the first time the presence of a huge 'double-eye' atmospheric vortex at the planet's south pole. This striking result comes from analysis of the data gathered by the spacecraft during the first orbit around the planet.  On 11 April this year, Venus Express was captured into a first elongated orbit around Venus, which lasted 9 days, and ranged between 350 000 and 400 kilometres from Venus' surface. This orbit represented for the Venus Express scientists a unique opportunity to observe the planet from...

Greater understanding of the characteristics of sun-like stars has provided astronomers with additional evidence for the uniqueness and fine-tuning of the solar system. The sun’s outer debris field, known as the Kuiper Belt, contains objects that provide important information about solar system formation. Hubble Space Telescope images reveal debris disks around other stars analogous to the Kuiper Belt. However, these debris disks show a wide variety of sizes, densities, locations, and planetary configurations - even when looking at stars that astronomers expect would form solar systems like the sun’s. Instead of providing evidence for the averageness of the solar system,...

Astronomers knew there was something odd going on when they looked for Uranus' newly discovered outer rings. For starters, they could only find one. After months of analysis, they figured out why: Unlike its red partner, the missing ring is so blue, it fell outside the telescope's range. "It's funny that this research got started by something we didn't see," said Imke de Pater, with the University of California at Berkeley and lead author of a paper describing the discovery in this week's journal Science. The initial discovery of a pair of outer rings circling Uranus was made by astronomers...

Astronomers have discovered that the planet Uranus has a blue ring - only the second found in the Solar System. Like the blue ring of Saturn, it probably owes its existence to an accompanying small moon. Scientists suspect subtle forces acting on dust in the rings allow smaller particles to persist while larger ones are recaptured by the moon. Smaller particles reflect blue light, giving the ring its distinctive colour, the US team reports in Science. All other rings - those around Jupiter, Saturn, Uranus and Neptune - are made up of both large and small particles, making the...

For Release: April 5, 2006 NASA's Spitzer Space Telescope has uncovered new evidence that planets might rise up out of a dead star's ashes. The infrared telescope surveyed the scene around a pulsar, the remnant of an exploded star, and found a surrounding disk made up of debris shot out during the star's death throes. The dusty rubble in this disk might ultimately stick together to form planets. This is the first time scientists have detected planet-building materials around a star that died in a fiery blast. "We're amazed that the planet-formation process seems to be so universal," said Dr....

LOS ANGELES - Scientists think they have solved the mystery of how planets form around a star born in a violent supernova explosion, saying they have detected for the first time a swirling disk of debris from which planets can rise. The discovery is surprising because the dusty disk orbiting the pulsar, or dead star, resembles the cloud of gas and dust from which Earth emerged. Scientists say the latest finding should shed light on how planetary systems form. "It shows that planet formation is really ubiquitous in the universe. It's a very robust process and can happen in all...