Although the image below isn't particularly striking, do focus in on it for a moment. You're looking at what astronomers now consider the coldest brown dwarf yet to be found. Look just down from the top of the image and just left of center for the unusually red pinpoint. This is CFBDS J005910.83-011401.3, thankfully abbreviated CFBDS0059. A science fiction writer with brown dwarf credentials (Karl Schroeder is just the guy) could think of a more poetic name and set up a story around such a place. Image: Three-color image of the star field in which the brown dwarf has been discovered. The brown dwarf is the very red object seen at the top left of the image. This image illustrates how very different is the color of this object compared to the other cold stars around. Image copyright Canada-France-Brown-Dwarf-Survey 2008. As interesting stars go, CFBDS0059 isn't all that far away, some forty light years. Massing between 15-30 Jupiter masses, it's typical of brown dwarfs in at least one...

Keep your eye on a project in the Canary Islands called the New Earths Facility. Using a laser measuring device now being tuned up for the job, scientists intend to continue the hunt for terrestrial worlds with a greater than ever chance of success. Called an astro-comb, the device brings far greater precision to our existing Doppler techniques for finding exoplanets. In fact, early reports suggest it may increase the resolution of these methods by as much as one hundred times, making the detection of an Earth-like world in an orbit similar to ours feasible. Now we're getting into interesting territory indeed, not only in terms of planetary detections themselves but synergies with the ambitious Kepler mission, to be launched in 2009. Read on. Studying the Doppler shift of distant starlight has already achieved a remarkable precision, capable of finding planets down to about five Earth masses in orbits as far from the star as Mercury. But the farther we get from the star, the trickier...

Long before the first exoplanets were found, one speculation about our own Solar System was that a passing star had disrupted the solar nebula so as to promote the formation of planets. We now know that planets form in many ways, but it's interesting to see that HL Tau, a star discussed yesterday at the Royal Astronomical Society meeting in Belfast, may have been influenced by a recent close pass by XZ Tau, another young star nearby. Did this 'flyby' disrupt the circumstellar disk around HL Tau, helping to form a proto-planet that has now been observed? Whatever the case, we do seem to have interesting processes at work around HL Tau. The newly discovered proto-planet is thought to be only one percent of the age of a planet found last year around TW Hydrae, a world ten times the mass of Jupiter that was once the youngest planet yet detected. That one orbited inside the inner hole of a pronounced circumstellar disk. HL Tau b remains little more than a bright clump within its dusty...

Results from the Wide Angle Search for Planets (SuperWASP) could hardly be better. In the last six months, astronomers using wide-field cameras in the Canary Islands and South Africa, working in conjunction with a battery of telescopes around the world, have identified ten new planets around other stars. The findings were announced yesterday at the Royal Astronomical Society's national meeting in Belfast. We're dealing with planetary transits here, planets moving across the face of their star as seen from Earth. 46 transiting worlds are known, of which SuperWASP has now found a solid fifteen. Skymaps, coordinates and background information on all the SuperWASP planets can be found here. You'll want to concentrate on WASP-6b through 15-b for the new ones, which include 'hot Jupiters' like WASP-12b (orbiting its primary, a G-class star 870 light years from Earth, in just over a day) and WASP-15b, one-half the mass of Jupiter, orbiting an F5 star a thousand light years away. The largest...

Budding astrobiologists should be thinking about the significance of red dwarf stars as they approach their careers. Let's say, as pure speculation, that one out of every thousand stars in class M has a planet in the habitable zone. That works out to 75 million potentially habitable planets around these stars in our galaxy alone. Note the assumptions I'm making. First, I peg M dwarfs at 75 percent of the galactic population. That figure is widely in use and I've just run across it again in a new paper by Paul Shankland (US Naval Observatory), David Blank (James Cook University, Australia) and colleagues, about which more in a moment. Another assumption: That the Milky Way holds about one hundred billion stars. That's low-balling the number, I think, because estimates seem to start at that figure and go up to four or five times as high. So my 75 million potentially habitable planets, while just a guess, may not be totally off the wall. Image: An artist's impression of a gas giant...

I've never met George Ricker, but in at least one respect I believe he thinks the way I do. Ricker is senior research scientist at MIT's Kavli Institute for Astrophysics and Space Research, and he's someone who can connect the exoplanetary systems we study with places we might eventually go. As witness this comment in a discussion of a planned satellite-based observatory being designed at the Institute: "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. 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." It's wonderful to see a 'when' rather than an 'if' when referring to starships, even though everyone concerned can appreciate the blue-sky nature of the comment. For my part, I'll take whatever the physics will bear, from close-up imagery of terrestrial exoplanets...

The recent news that there may be an underground ocean on Titan tantalizes us in astrobiological terms. It also brings us up against the question of how to define a habitable zone. The standard definition involves the presence of liquid water at the surface, a reasonable requirement when you're looking for carbon-based life. But it's also true that exobiology may one day be studying forms of life that are nothing like us, living in environments we would at first dismiss from our list of living places. Just how far does a habitable zone extend? First, a short defense of the status quo. As we expand our exoplanet hunt and become capable of detecting the signature of life on distant planets, we need a target list to optimize our search time. It's entirely reasonable to fine-tune that list toward conditions similar to what we find on Earth because the life on our planet is the only kind we've been able to study. Detecting its biomarkers in an alien atmosphere is a sensible goal. We know...

Well-studied HD 189733b is a Jupiter-sized planet again in the news. Studying this transiting world, scientists using Hubble Space Telescope data have made the first identification of an organic molecule -- methane -- in the atmosphere of an exoplanet. What's particularly significant here is the growing sophistication of our use of spectroscopy, splitting light into its components to tease out the constituents of the atmosphere under study. This new finding shows that we're on target in planning to use space-based observatories to make far more challenging detections. Image: A wide field image of the region of sky in which HD 189733b is located. In this image we can see the asterism of the "Summer Triangle" a giant triangle in the sky composed of the three bright stars Vega (top left), Altair (lower middle) and Deneb (far left). HD 189733b is orbiting a star very close to the centre of the triangle. Credit: A. Fujii. Methane in the atmosphere of a gas giant wouldn't rank as a...