Three Neptune-sized Planets Found Nearby 337
WillAffleckUW writes "CNN reports the discovery of three Neptune-sized planets found in orbit around a sun 41 light years away. The star they orbit is similar to our Sun, and the planetary distribution is probably similar to our Solar System. Recent observations by NASA's Spitzer Space Telescope last year revealed that HD 69830 also hosts an asteroid belt, making it the only other sun-like star known to have one. No word on if they have habitable moons, or monoliths yet."
It's still in the Milky Way (Score:5, Informative)
Re:It's still in the Milky Way (Score:3, Informative)
Re:Which planet again? (Score:2, Informative)
So if I understand you right.... (Score:2, Informative)
Re:Let's use some familiar units people! (Score:1, Informative)
192 planets and counting (Score:3, Informative)
It wasn't that long ago (err, wow, 10 years, maybe that's long) that the first extrasolar planet was discovered. I still remember that news announcement I watched on TV...
Anyway, since the discovery of those 3 planets, another planet has been found. Check out the exoplanet encyclopedia [exoplanet.eu] (my favourite exoplanets site). It has a catalog with all the data of those planets, some with uncertainty factors. Discovery method, size, catalogue number, the whole lot. Try chucking all that into a spread-sheet, and plot some scatter graphs. Should be a lotta fun. The last time I tried this, it was a bit problematic because the masses are not really known (for planets discovered using spectral shifts), but are merely minimum (maximum?) limits only. But still, an order of magnitude plot could be fun.
Anyway, the 3 planets are already in the catalogue under HD 69830 [exoplanet.eu]. Don't forget to check out this one [exoplanet.eu] as well. Exciting times. I look forward to 200 planets!
Re:Inteligent Life (Score:3, Informative)
Very difficult, but perhaps not impossible. (Score:3, Informative)
Assume that the aliens have a radio telescope that is comparable to the one at Arecibo [nasa.gov]. I don't have numbers on its sensitivity after recent upgrades [oemagazine.com], but a ball-park figure I have heard is that it can pick up a cell phone transmission within a sizable part of the solar system near earth.
A rough calculation reveals that perhaps a 10^14 W source at the centre of our galaxy (2.2 x 10^4 light-years away) could be detected by Arecibo. Compare this to terrestrial television (~10^6 W) and radio (~10^5) stations, and you'll find that it could be on the edge of possiblility for Arecibo to pick up TV transmissions from a planet 41 light-years away.
Re:What's the point of all this? (Score:1, Informative)
What is a light-year and how is it used? (Score:3, Informative)
Mars (Score:3, Informative)