MAIN ARTICLE: Super Earth + Ice = Alien Life?
""We know there are a lot of super-Earths out there, and the next generation of telescopes will be even better at spotting them," - Scott Gaudi, assistant professor of astronomy at Ohio State University.
Poll Results: A strong turnout in yesterday'spoll:"Should America fund a COTS-D program to close the gap." Scroll down to see the most recent space DKOS members opinion poll results
Star Trek: In the News. T'Bonz from Trek Today discusses recent comments by JJ Abrams. For everything Star Trek scroll down. Click subscribe to stay informed.
Yesterday's Comments: "Curiously, it was also my nickname in college" - The Fonging
Today's Poll: "Looking for Life in all the Wrong Places."
Scientists are looking for possable planetary locations for alien life and stretching the search to include some unlikely planets. Icey cold "Super Earths" huge planets buried in ice orbiting stars outside our solar system.
EXOPLANET:
"An extrasolar planet, or exoplanet, is a planet beyond the Solar System, orbiting around another star. As of December 2008, 333 exoplanets are listed in the Extrasolar Planets Encyclopaedia.[1] The vast majority have been detected through radial velocity observations and other indirect methods rather than actual imaging.[1] Most announced exoplanets are massive gas giant planets thought to resemble Jupiter, but this is a selection effect due to limitations in detection technology. Projections based on recent detections of much smaller worlds suggest that lightweight, rocky planets will eventually be found to outnumber extrasolar gas giants.
Extrasolar planets became a subject of scientific investigation in the mid-19th century. Many astronomers supposed that such planets existed, but they had no way of knowing how common they were or how similar they might be to the planets of the Solar System. The first confirmed radial velocity detection was made in 1995, revealing a gas giant planet in a four-day orbit around the nearby G-type star 51 Pegasi. The frequency of detections has tended to increase on an annual basis since then.[1] It is estimated that at least 10% of sun-like stars have planets, and the true proportion may be much higher.[3] The discovery of extrasolar planets sharpens the question of whether some might support extraterrestrial life.
Currently, Gliese 581 d, the third planet of the red dwarf star Gliese 581 (approximately 20 light years from Earth), appears to be the best example yet discovered of a possible terrestrial exoplanet that orbits close to the habitable zone surrounding its star. Although Gliese 581 d appears to reside outside the so-called "Goldilocks Zone", a potential greenhouse effect might raise the planet's surface temperature high enough to support liquid water."
Looking for extraterrestrial life in all the right places
"We know there are a lot of super-Earths out there, and the next generation of telescopes will be even better at spotting them," said Scott Gaudi, assistant professor of astronomy at Ohio State University.
Despite the name, a super-Earth has little in common with the Earth that we know -- other than the fact it is has a solid surface. A super-Earth is covered with ice, and may have a substantial atmosphere – perhaps much thicker than the Earth’s.
Yet Gaudi joined with Eric Gaidos of the University of Hawaii and Sara Seager of the Massachusetts Institute of Technology to model whether such planets might harbor a liquid ocean that could support life, and whether they might be detectable from Earth.
Gaidos reported the team's early results at the
American Geophysical Union meeting in San Francisco.
"It turns out that if super-Earths are young enough, massive enough, or have a thick atmosphere, they could have liquid water under the ice or even on the surface," Gaudi said. "And we will almost certainly be able to detect these habitable planets if they exist."
"The most promising technique for finding super-Earths is the one Gaudi prefers: gravitational microlensing. When one star happens to cross in front of another as seen from Earth, it magnifies the light from the more distant star like a lens. If planets are orbiting the lens star, they boost the magnification briefly as they pass by.
Gaudi and his colleagues first discussed the project this summer at an Aspen Center for Physics workshop. The workshops are sponsored by the National Science Foundation, and they offer an informal atmosphere for scientists to propose new ideas.
There, the three talked about using microlensing to search for life in a new way.
Most such efforts focus on finding planets in another solar system's "habitable zone" -- the distance from a star where temperatures are just right for supporting liquid water on the surface and thus life as we know it.
But water is much more plentiful beyond the habitable zone, in the outer reaches of a solar system, Gaudi explained. It's most often found as ice -- at the heart of gas planets such as Jupiter, on frozen moons such as Europa, and on super-Earths. In fact, Earth's water probably originated elsewhere, and found its way here on comets or asteroids."
Will life be found? It would be early to start speculating but with an estimated 500 billion planets in the Milky Way Galazy alone it would seem likely there is life somewhere else.
Gravitational microlensing:
"is an astronomical phenomenon due to the gravitational lens effect. It can be used to detect objects ranging from the mass of a planet to the mass of a star, regardless of the light they emit. Typically, astronomers can only detect bright objects that emit lots of light (stars) or large objects that block background light (clouds of gas and dust). These objects make up only a tiny fraction of the mass of a galaxy. Microlensing allows the study of objects that emit little or no light.
When a distant star or quasar gets sufficiently aligned with a massive compact foreground object, the bending of light due to its gravitational field, as discussed by Einstein in 1915, leads to two distorted unresolved images resulting in an observable magnification. The time-scale of the transient brightening depends on the mass of the foreground object as well as on the relative proper motion between the background 'source' and the foreground 'lens' object.
Since microlensing observations do not rely on radiation received from the lens object, this effect therefore allows astronomers to study massive objects no matter how faint. It is thus an ideal technique to study the galactic population of such faint or dark objects as brown dwarfs, red dwarfs, planets, white dwarfs, neutron stars, black holes, and Massive Compact Halo Objects. Moreover, the microlensing effect is wavelength-independent, allowing to study source objects that emit any kind of electromagnetic radiation.
Microlensing by an isolated object was first detected in 1993. Since then, microlensing has been used to constrain the nature of the dark matter, detect extrasolar planets,"
"Gaidos and Seager found that very big super-Earths, ones around 10 times the mass of Earth, could retain enough heat from their formation to form a liquid ocean beneath the ice -- even though those planets would be located some five times farther from their star than the Earth is from its sun.
Gaudi determined that such planets would be detectable. In fact, microlensing is best at detecting planets that far out in a solar system, he said.
"A more worrisome question is, if these planets have life on them, how would we know it? We have a hard enough time trying to figure out where there's life on Europa, let alone something that's hundreds of light years away," he added."Searching For Life On Colder Planets
FUTURE TELESCOPES:
KEPLER:
"The scientific objective of the Kepler Mission is to explore the structure and diversity of planetary systems. This is achieved by surveying a large sample of stars to achieve several goals:
Determine how many terrestrial and larger planets there are in or near the habitable zone of a wide variety of spectral types of stars
Determine the range of sizes and shapes of the orbits of these planets
Estimate how many planets there are in multiple-star systems
Determine the range of orbit size, brightness, size, mass and density of short-period giant planets
Identify additional members of each discovered planetary system using other techniques
Determine the properties of those stars that harbor planetary systems"
JAMES WEBB:
"The James Webb Space Telescope (JWST) is a planned space infrared observatory, the successor to the aging Hubble Space Telescope. The main scientific goal is to observe the most distant objects in the universe, those beyond the reach of either ground based instruments or the Hubble. JWST is a NASA-led international collaboration between NASA, the European Space Agency and the Canadian Space Agency. Formerly called the Next Generation Space Telescope (or NGST), it was renamed after NASA's second administrator, James E. Webb, in 2002. The telescope's launch is planned for no earlier than June 2013. It will be launched on an Ariane 5 rocket."
Future Ares V Missions (70 pages covering 12 different missions)
With NASA's new proposed heavy lift launch vehicle, Ares V, many in the scientific community are already looking at new missions that could take advantage of the 207 tons it can lift to Low Earth Orbit (LEO).
The National Academies: Advisors to the Nation on Science, Engineering and Medicine
"The Space Studies Board and the Aeronautics and Space Engineering Board of the National Research Council (NRC) have begun a study of science opportunities enabled by NASA’s Constellation system of launch vehicles and spacecraft. The Committee on Science Opportunities Enabled by NASA’s Constellation System will first analyze a set of "Vision Mission" concepts provided by NASA. The results of this analysis will be included in an interim report to be completed by the end of April 2008. The mission concepts that the committee is analyzing for its interim report are listed on the committee’s website." - Call for Papers
POLL RESULTS:
Yesterday's poll, "Should America fund a COTS-D program to close the gap."
41% of members voting wanted 2 billion spent on a COTS-D program only 15% thought private industry should pony up all the funding themselves.
STAR TREK: In the News.
"Following the recent news that Majel Barrett will be reprising her role as the computer voice for the new Trek film, director J.J. Abrams said this week that such guest appearances aren't simply meaningless cameos.
"I think what you'll see is there are -- both story-wise and performance-wise, visually and aurally -- many connections to what is familiar and what has come before," Abrams told MTV. "Which for the new fans of Star Trek, the newcomers to the world, will be irrelevant. But for those people who are fans and who hope for or expect certain familiar nods, they will undoubtedly get those." " - Trek Today
YESTERDAY'S COMMENTS:
Is this the place for science-y stuff? I just read an article that talks about how Scientists have recently found a hole in the Earth's magnetic field! I have a linky too:
Scientists find hole in Earth's magnetic field I found it interesting at least..." - Luthien Tinuviel
Science links are welcome! Feel free to post any interesting space or science diary or link. If you are posting a personal diary then giving this diary a plug would be greatly appreciated.
"Private contractors - Reminds me of the quote from Armageddon.
'You know we're sitting on four million pounds of fuel, one nuclear weapon and a thing that has 270,000 moving parts built by the lowest bidder. Makes you feel good, doesn't it?' " - Casual Wednesday
"Stolen from a quote attributed to John Glenn on his first orbital flight in 1962:
"As I hurtled through space, one thought kept crossing my mind: Every part of this capsule was supplied by the lowest bidder."
(So sez Wikibut no one's posted an original source yet. Even so, the quote is referenced in Tom Wolfe's The Right Stuff, so if it isn't stolen from Glenn it's stolen from Wolfe.)
I am morally certain that whoever put together Armageddon managed to get hold of (NB I did not say "steal") a copy of an early script for Deep Impact (which came out about the same time) & said, Jeezus key-Rist this is pretentious, how about we put together a script that parodies the living crap out of it & then get Bruce Willis to deliver the smartass lines... Compare the two sometime & then tell me I'm wrong." - Uncle Cosmo
"I'll be contrarian tonight - I believe we should focus our space activities on our own troubled planet. If the science we need to do to help understand and address climate change and its consequences can best be accomplished with womaned space flight, then the expense is justified. If not, then it might be better to call manned flight off for a while. It encourages escapist fantasies, at the expense of neglecting Spaceship Earth. There is a limited science budget and every funding decision entails opportunity costs. I suspect the opportunity costs of the manned space program are too large. If the warriors were not interested in space, we would not be sending people up there. I say only poets should lift off." - catadromous
TODAY'S POLL:
As space telescopes continue to improve in capability it will soon be possible to detect a rocky earth in the "habital zone". That area who's distance from it's parent star allows water to stay as a liquid rather then boiling off or staying a frozen iceball.
Once we detect them we can start analyzing the atmosphere to see if there is life. The question is, should we be looking and if we find it, then what? Try and make contact?