Nearby Star Not Too Old to 'Birth' Planets; New Study

A star may not be done making planets just yet. A star thought to have passed the age at which it can form new worlds may be still creating them. The disk of material surrounding the star, named TW Hydrae, may be massive enough to produce more planets than we have in our own solar system.

Planets are born from the material swirling around young stars. The mass of this material is a key factor controlling their formation. Older stars usually clear out their surrounding material, making it difficult or impossible for them to create new planets.

At roughly 10 million years old and 176 light years away, the TW Hydrae is relatively close to Earth by astronomical standards and has been well studied in the past. Although the star itself is still relatively young, it's past the age at which giant planets usually form. Yet the findings, observed using the European Space Agency's Herschel Space Telescope, showed that TW Hydrae had more gas than usual surrounding it. The observed material may be one of the reasons why this star is still producing planets. It currently still has enough mass surrounding it to make the equivalent of 50 Jupiters.

But the researchers didn't only note the star's unusual circumstances. The findings also demonstrated a new, more precise method for weighing planet-forming disks. Previous techniques for measuring the mass were both indirect and uncertain. This new method can directly probe the gas that typically goes into making planets. Scientists used Herschel to analyze the light coming from TW Hydrae and pick out the spectral signature of hydrogen deuteride, a gas. With their new method, they were able to measure the levels of this gas and obtain the weight of the disk.

These results could point to the possibility that this star could create a diverse new planetary system. However, there is no guarantee. Researchers are quick to point out that numerous factors are involved when planets are formed.