Nearby Solar System Looks Like Home 62
sciencehabit writes "Gliese 581 is a red dwarf star just 21 light-years from Earth that boasts a number of planets. Now astronomers are reporting another feature that earthlings would find familiar: a ring of dust far from the star which resembles the Edgeworth-Kuiper belt, a zone of objects, each much smaller than Earth, that lies beyond Neptune's orbit and includes Pluto. The newfound debris disk is about as large as the Edgeworth-Kuiper belt, even though Gliese 581 is small and all of its known planets lie closer to their sun than Earth does to ours. The scientists speculate that the little red star harbors a more remote planet whose gravity stirs up the belt's small objects, causing them to collide and spew the dust that Herschel has discerned."
Frost Line and Hot Jupiters (Score:4, Insightful)
The scientists speculate that the little red star harbors a more remote planet whose gravity stirs up the belt's small objects, causing them to collide and spew the dust that Herschel has discerned.
This seems plausible if the frost line [wikipedia.org] hypothesis is correct. In that case you would always expect to have gas giants stirring up matter on the edge of a solar system. The problem is that many gas giants have been found very close to stars and inside the frost line (the Hot Jupiters [wikipedia.org]). Until there is a good explanation for the Hot Jupiters, I don't think we can just blindly expect to find gas giants beyond the frost lines stirring up asteroids.
Re:Less Speculation, Please (Score:5, Insightful)
I don't see speculation anywhere in the scientific method.
You don't? Perhaps you should reflect on the meaning of the word "hypothesis."
Despite all the complaining... (Score:5, Insightful)
This would leave the Fermi paradox without one of its better possible explanations: that habitable worlds are exceedingly rare.
It also means that human colonies in other solar systems may be more plausible than it currently seems.
Re:Spoiler: (Score:5, Insightful)