29 November 2013
Star System Found - Similar to Ours
“We cannot stress just how important this discovery is. It is a big step in the search for a ‘twin’ to the Solar System, and thus also in finding a second Earth. No other planetary system shows such a similar ‘architecture’ to that of our cosmic home as does the planetary system around KOI-351.
Just as in the Solar System, rocky planets with roughly the size of Earth are found close to the star, while, ‘gas giants’ similar to Jupiter and Saturn are found as you move away from the star.
Until now, 771 stars with planets have been identified. However, most of the exoplanets discovered so far are ’solitary’. Only 170 stars are known to be orbited by more than one planet. The outermost planet orbits the star at a distance of about 150 million kilometres, or roughly one Astronomical Unit (AU), so the entire planetary system is compressed into a space corresponding to the distance between Earth and the Sun.
To detect such small planets, a special algorithm was developed by Cabrera. Besides the size of these planets, what is remarkable is the 5:4 orbital resonance. In the time it takes planet b to complete five orbits, planet c has completes exactly four orbits. Similar resonances are found among the inner moons of Jupiter.
Unpublished: early life on earth used fewer minerals, mission incredible :-),
Upplagd av Ola kl. 01:02