Gemini and Keck directly image planetary system
I hope to post more on topic soon. I haven’t been able to recently due to various commitments.
This just seemed so cool, though, that I thought it was worth a short post, and more importantly, a link.
According Dr. Marois, this discovery is the first time we have directly imaged a family of planets around a normal star outside of our solar system. Team member Bruce Macintosh of the Lawrence Livermore National Laboratories adds, “Until now, when astronomers discover new planets around a star,
all we see are wiggly lines on a graph of the star’s velocity or brightness. Now we have an actual picture showing the planets themselves, and that makes things very interesting.” The discovery article is published in the November 13, 2008, issue of Science Express, an international weekly science journal.
The host star (a young, massive star called HR 8799) is about 130 light years away from Earth. Comparison of multi-epoch data show that the three planets are all moving with, and orbiting around, the star, proving that they are associated with it rather than just being unrelated background objects coincidentally aligned in the image. HR 8799 is faintly visible to the naked eye, but only to those who live well away from bright city lights or have a small telescope or even binoculars, see online finder charts here.
The planets, which formed about sixty million years ago, are young enough that they are still glowing from heat released as they contracted. Analysis of the brightness and colors of the objects (at multiple wavelengths) shows that these objects are about seven and ten times the mass of Jupiter. As in our solar system, these giant planets orbit in the outer regions of this system – at roughly 25, 40, and 70 times the Earth-Sun separation. The furthest planet orbits just inside a disk of dusty debris, similar to that produced by the comets of the Kuiper Belt objects of our solar system (just beyond the orbit of Neptune at 30 times the Earth-Sun distance). In some ways, this planetary system seems to be a scaled-up version of our solar system orbiting a larger and brighter star. First Direct Images Of A Planetary Family Around A Normal Star
While this is a fairly special case, which won’t be often replicated in other stellar systems with the present telescopes, we’re getting a lot closer to actually studying extra-solar planets. Which does, of course, have a lot to do with the evolution of life.
We really need the space-based interferometers and other instruments to study extra-solar planets, and possibly to find out something about the origin and evolution of life on other planets.