Nov 23 2008
It’s been an interesting week, okay, week-and-a-half since my last post. Although I haven’t made as much progress on the NaNoWriMo novel as I’d have liked, I have got two more short stories out for consideration. I’m not counting those in my NaNoWriMo word counts. It’s also been an interesting time for planetology. We’ve photographed (or perhaps “imaged” might be a more accurate term) planets around no less than three other star systems, and discovered interesting things about the history of water on Mars.
On Nov. 13, NASA announced that the Hubble Space Telescope had succeeded in photographing a planet orbiting the star Fomalhaut, a mere 25 light years away (putting it just within T-Space). Fomalhaut is a youngish star (100 to 300 million years old), with about twice the mass and twenty times the luminosity of our Sun. The planet is Saturn-sized and extremely distant from its sun.
Almost simultaneously, scientists at the Herzberg Institute of Astrophysics announced that, using the Keck and Gemini telescopes, had imaged (in infrared) three planets orbiting the star HR 8799. This star is younger than Fomalhaut (perhaps 60 million years old) and further away, about 130 light years. The planets of younger stars may be easier to spot, especially in infrared, because they’re still glowing with the heat of their own formation.
On Friday, Nov. 21, a team at ESO announced that images of a previously suspected planet around Beta Pictoris had been obtained with the Very Large Telescope. Apparently the image was captured a while back but not noticed until the data was recently re-examined. Beta Pictoris is about 64 light years away and again, bigger and hotter than our sun, and perhaps even younger than HR 8799.
Being so young, none of the above planetary systems are particularly likely to have any life at all, let alone complex or intelligent lifeforms. (The upper age range of Fomalhaut would put it at just about the age where the chemical soup on Earth may have started to favour complex molecules that could replicate.)
Closer to home, and much older, glaciers have been found on Mars much closer to the equator than expected, protected from evaporation by layers of soil, and analysis of gamma-ray spectrometer results from Mars Orbiter adds further evidence that early Mars once had an extensive ocean, or oceans.
So, places that may one day have Earthlike (loosely speaking) planets, and a neighbor planet that was once much more Earthlike than it is now. The hunt is still on for currently Earthlike planets.