The New Earth That Wasn't

Scientists have recently announced the discovery of an earthlike planet orbiting around Gliese 581, and I wondered what a few of my favorite astrometric sites had to add to the story.

Sol Station

Al Fin has a satirical piece offering more hope for the future than I currently have in my heart.

ISDB [Internet Stellar Database]

and for the non-geeks, there is Wikipedia.

What does all the jargon mean? Is it really earthlike?

Here is the money quote from the Sol Station HO Librae page:

The more Earth-like planet "c" has at least 5.03 Earth-masses (or 0.0158 Jupiter-masses) and an estimated diameter of at least 1.5 times Earth's if it is rocky, larger if it is composed of mostly ice. It moves around Gliese 581 -- outside of planet b's orbit -- at an average distance of 0.073 AU, in a circular orbit (e=0.28 ± 0.06) which it completes in 12.932 (± 0.007) days. Located within the so-called habitable zone of Gliese 581 (which may be centered around 0.11 AUs from the star), the planet may have a mean temperature between -3 and over 40 degrees Celsius (27 and 104+ degrees Fahrenheit) with water on its surface, depending on whether the planet has a Venus- or an Earth-like albedo.




The data above means no. Not habitable the way we think about it. The planet is close enough to the star to be tidally locked, one side forever facing Gliese 581 as it races nearly 40 mps in it's orbit.
Also, the star is a UV Ceti Flare Star, so it is subject to violent flares and changes in luminosity over time. Not a good place to be without solar armor.
It is exciting, though, that our ability to detect smaller and smaller planets is getting better. I would love to see an observatory built on the farside of the moon before I die, but I am beginning to seriously doubt that, as there are indications that the Luddites are going to win, and we will slide into barbarism for a few millenia before we get another run at leaving the earth. Oh well, it was fun while it lasted.

Can you tell that astronomy and physics were my first, best path? Becoming an astrophysist is quite an expensive proposition...so I went to work after High School.