MetaFilter posts tagged with astronomy and exoplanets

Exoplanet Hunter

Chinese Jet Pilot — Wed, 15 May 2013 14:28:43 -0800

"It was one of those things that was a gift to humanity... We’re all going to lose for sure." Kepler's career is over, but not before answering one of mankind's most profound questions.

The Final Frontier

Artw — Tue, 12 Mar 2013 07:16:10 -0800

Astronomers Conduct First Remote Reconnaissance of Another Planetary System

Ad Astra Incrementis

audi alteram partem — Tue, 01 May 2012 04:14:08 -0800

Carl Sagan wrote, “We began as wanderers, and we are wanderers still. We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars.” But how will humans or our machine representatives fly to the stars? The Tau Zero Foundation describes itself as “a volunteer group of scientists, engineers, entrepreneurs, and writers who have agreed to work together toward practical interstellar flight and to use this quest to teach you about science, technology, and our place in the universe.” The foundation takes its name from Poul Anderson’s 1970 novel. In the book, a crew find themselves trapped on a runaway spaceship. They approach so close to the speed of light that their experience of time dilation, their tau factor, results in tens of billions of years passing in the outside universe while they experience a handful of years on-board. The projects envisioned by the Foundation travel at less fantastic speeds, but they still evoke a sense of wonder. The Foundation’s blog Centauri Dreams, run by Paul Gilster (author of a book by the same title), reports on various astronomical and aerospace research projects relevant to interstellar exploration. True to its motto “Ad Astra Incrementis” the Foundation promotes projects that use today’s technology as stepping stones for future interstellar exploration. While Glister notes that breakthough advances in physics and engineering will always be possible (resulting in warp drives and other exotic means of locomotion), the Foundation focuses on technologies that are in our reach if not our grasp. Coverage includes both technology already deployed (solar sails and ion engines) to theoretical designs (beamed energy sails and nuclear pulse propulsion) that could propel a probe at considerable fractions of light speed. The Foundation considers the technological and cultural infrastructure needed to develop interstellar technologies through the 100 Year Starship Study and the Project Icaraus update to the 1970s Project Daedalus conceptual interstellar probe. One project that could serve as an early testbed for interstellar technology is Claudio Maccone's FOCAL project to send a telescope 550 times the distance from the Earth to the Sun in order to take advantage of Sun’s gravitational lens. Centauri Dreams also tracks projects that could provide specific targets for interstellar probes, particularly methods for studying exoplanets that would show evidence of biological activity, and looking for planets similar to Earth as well as understanding the range of habital biozones possible around stars unlike our own. Ultimately the Foundation sees a dual goal in pursuing interstellar flight:

It touches on the deepest meaning of what we are as a species and our place in the Universe.... The enormous benefits of practical interstellar flight should be obvious. Not only would it free humanity from having just one safe haven, but it would also generate profound technological spin-offs.

1,000 new worlds

IvoShandor — Thu, 01 Mar 2012 19:12:55 -0800

NASA has announced that the latest Kepler data dump contains 1,091 extrasolar planet candidates, with 196 Earth-sized planets among them. The data shows "a clear trend toward smaller planets at longer orbital periods is evident with each new catalog release. This suggests that Earth-size planets in the habitable zone are forthcoming if, indeed, such planets are abundant." Total Kepler candidates as of February 27, 2012: 2,321. Related: *Check out this "orrery-type visualization" of candidate star systems with more than one transiting planet. *Help search for exterrestrial radio signals at setilive.org.

The tiniest star system

IvoShandor — Wed, 11 Jan 2012 15:49:03 -0800

Astronomers using data from NASA's Kepler mission have discovered the three smallest planets yet detected orbiting a star beyond our sun. The planets orbit a single star, called KOI-961, and are 0.78, 0.73 and 0.57 times the radius of Earth. The smallest is about the size of Mars.

Other earths, circling different suns

Kattullus — Mon, 05 Dec 2011 11:21:11 -0800

The Habitable Exoplanets Catalog is a database of the planets outside our solar system which are considered the most suitable for life according to certain steps and metrics. So far 16 have been identified as possible candidates. This Guardian article is a good introduction. You can also just dive into the catalogue, which ranks planets on two main scales, similarity to Earth and surface habitability (note that all images are computer renderings). The catalog is a project of the Planetary Habitability Laboratory at University of Puerto Rico in Arecibo (home to the world's largest radiotelescope).

French scientists reportable habitable planet orbiting another star

Ipsifendus — Thu, 26 May 2011 18:12:25 -0800

French scientists have just published a paper entitled "Gliese 581d is the 1st discovered terrestrial-mass exoplanet in the habitable zone", claiming that their computer model suggests the exoplanet "will have a stable atmosphere and surface liquid water for a wide range of plausible cases." We've discovered a lot of exoplanets. And there are a lot of sites to help you keep track. Previously.

Only YOU can help find exoplanets!

brundlefly — Fri, 17 Dec 2010 14:15:45 -0800

Planet Hunters lets users comb through data from the Kepler mission in search of exoplanets. [via Bad Astronomy]

Planets made of diamond and graphite?

philipy — Wed, 08 Dec 2010 11:53:20 -0800

A hot carbon-rich gas giant exoplanet, WASP-12b, has been discovered. As the lead author of the paper being published today, Nikku Madhusudhan, says: ""This planet reveals the astounding diversity of worlds out there". In particular, the discovery supports theories that there are likely to be planets made of diamond and graphite out there.

"A novel metric of habitability"

IvoShandor — Mon, 20 Sep 2010 22:16:39 -0800

Amid news of new extrasolar planet discoveries, including a system with a possible 7 planets, Greg Laughlin and Sam Arbesman have released a paper that will be published next month in the open-access journal PLoS One. "A Scientometric Prediction of the Discovery of the First Potentially Habitable Planet with a Mass Similar to Earth" (pdf of full paper) boldly predicts that: "the first potentially habitable planet will be discovered, in this case, as early as May 2011, and likely by the end of 2013." NASA's Kepler mission is set to release data on hundreds of candidate planets early next year. The mission has discovered 7 so far. (Pre-vio-usly)

You're not alone

Kronos_to_Earth — Sun, 06 Apr 2008 18:39:25 -0800

Many planets have been found circling other stars, but the prevailing search techniques turn up results encouraging but bizarre. (encouraging, previously) Gravitational micro-lensing has made it possible to OGLE a solar system much like our own.... You're not alone.