Giant Planet Gives Alternative Insight Into Planetary Evolution

A massive young planet, measuring 11 times Jupiter’s size, has given researchers a rare and alternative glimpse at planet formation’s final stage. The fledgling gas giant HD 106906b, which is estimated to be about 13 million years old, is located in the constellation Crux around 300 light-years away from Earth.

The planet that belongs to the star system HD 106906 has roused the curiosity of scientists because its location does not support the current ideas of planet evolution. Researchers generally believe that star systems, such as our own Solar System, start out as a gigantic gas cloud that collapses under its own gravity and forms a debris disk in the process. Subsequently, planets form from the materials the debris disk provides as the gas slowly evaporates.

Until now, scientists have discovered 1,700 debris disks of which 40 have been resolved with infrared or optical imaging. However, what makes HD 106906 different is its planet HD 106906b, which is located 650 times further from its star as compared to the distance between the Earth and Sun. The huge distance makes the planet take 1,500 years to complete one orbit of its central star, which implies that HD 106906b has a larger orbit than any other extra solar discovered to date. However, the planet’s location has brought up questions regarding how and where it formed.

"This is such a young star; we have a snapshot of a baby star that just formed its planetary system," said co-author of the study Smadar Naoz, according to Press Release Point. “Our current planet formation theories do not account for a planet beyond its debris disk."

The recent study, published online in The Astrophysical Journal Letters, suggests that HD 106906b formed outside the debris disk and not inside it. According to the scientists, the findings go against the grain of planet evolution theories, but it works perfectly to explain the debris disk’s shape. The team of researchers came to its conclusion using a software program called Superparticle-Method Algorithm for Collisions in Kuiper belts and debris disks (SMACK), which was developed by study lead author Erika Nesvold from Carnegie Institution for Science.