December 29, 2010
This discovery, of a solar system similar to ours, was big news in 2010.
A very exciting discovery was announced today at the Observatoire de Haute-Provence, France.
Astronomers have detected a planetary system containing at least five - and maybe seven - planets that orbit a star called HD 10180, which is much like our own Sun. They say this is the "richest" system of exoplanets - planets outside our own Solar System - ever found.
Up until now, astronomers had known of fifteen systems with at least three planets, but never one that was this similar to ours in terms of the number of planets (seven as compared to the Solar System’s eight planets). The team also has evidence that the distances of the planets from their star follow a regular pattern, as also seen in our Solar System (this is known as the Titius-Bode law).
The star is 127 light years away, in the southern constellation of Hydrus.
Researchers used the HARPS (High Accuracy Radial velocity Planet Searcher) instrument at the European Southern Observatory to monitor light emitted from the system. The lead author of the paper, Dr. Christophe Lovis, explained how the planet searcher works. "If there is one planet it will induce a little movement - the star will come towards us and move away….and what works for one [planet] works for many." Using HARP, Dr. Lovis and his team were able to measure this complicated mix of movements and break it down into individual planets, calculating the mass of each planet and the path of its orbit.
Martin Dominik, one of the researchers on the project, told reporters why this discovery is so important to us here on Earth. "[This] marks the way towards gathering the information that will put our own existence into cosmic context."
I have been an amateur astronomer all my life, and was President of the Junior Astronomy Club at the American Museum of Natural History when I was in high school. I love science news stories like these - I guess that is why I’ve written as many books as I have about space. Kids can read more about stars and the exoplanets that orbit them in my book STARS.
Photo Credits for this Science News story:
The first photograph shows a close-up of the sky around the star HD 10180. The picture was created from photographs taken through red and blue filters and forming part of the Digitized Sky Survey 2. Provided courtesy of ESO.
The second image is an artist’s impression of the new solar system, also courtesy of ESO.
Posted by: Liz Nealon
