The astronomy community is rocking. Say La Silla Chile 123 trilion times fast.
Scientists in Europe believe they have found a terrestrial planet orbiting a little ember of a star called Gliese 581 a mere 20.5 light-years from our solar system.
Astronomers separate known planets into “terrestrial” and “Jovian” types. The former, like Earth, are smaller, and made mostly of metal and dirt. The latter, like (you guessed it) Jupiter, are large and largely gaseous, consisting of methane and other substances surrounding a small solid core. At least that’s how I remember things.
As with members of multiple-star systems, the planet, dubbed 581 c, has given itself away by its effect on Gliese 581, which “wobbles” in a specific way as a result of its companion’s influence. We can’t see it; it’s believed to be less than 7 million miles from its sun, or about one eighteen-milionth the distance between us and the whole wonderful production. Its year is a fleeting 13 days. Methuselah would have lived to a grand old 25,000 or so there.
We already know of another planet orbiting Gliese 581, this one about the size of Neptune. The reason the discovery of 581 c is so compelling is that between Gliese 581’s size and temperature and 581 c’s orbital radius, the temperature on the planet is warm enough to support the existence of liiquid water. You can guess at the possible — not likely, but possible — implications.
The Bad Astronomy Blog has malefic coverage. Also, here’s a list of the 50 (or 49) nearest star systems, not including “the” sun; note that only seven of these are visible to the unaided eye, and only two would be considered bright.