Belt Of Comets Around Multi-Planet System Offers Clues About Wandering Planets

Wandering planets were directly imaged by astronomers by the use of the Atacama Large Millimeter, Submillimeter Array or ALMA, a radio observatory located in Chile. The team of astronomers was able to have the first ever high-resolution image of the strip of comets around the HR 8799, the star where the planets have been recently imaged.

The orbits of the wandering planets were observed to be inconsistent with the disk's shape, specifically the inner edge. According to the team, this shows that either the planets have changed their position over a period of time or there could be another wandering planet in the system that is yet to be found.

The report about the wandering planets, which was published in the Monthly Notices of the Royal Astronomical Society, will allow for the first time an image of the inner edge of the disk. Such disk fills the region of about 150 to 420 times the distance of the Sun and Earth and also created the existing collisions of those cometary bodies of the star system's outer regions.

In addition, the radio observatory ALMA was successful in imaging the emission coming from the millimeter-size bits of debris in the disk. The researchers said that the tiny size of these dust particles indicates that the wandering planets in the system are bigger that the Jupiter.  Based on past observations using other telescopes, such discrepancy in the disk was not detected, Phys.Org reported.

However, it is not certain if the difference was caused by the low resolution of the past observations or may likely due to different wavelengths that seem to be sensitive to various grain sizes.

Capturing the image of a multi-planet system, including the orbiting dust is first of its kind that allows direct comparison with the dynamics and the formation of the solar system. According to co-author Antonio Hales of the National Radio Astronomy Observatory, this would provide relevant information about the wandering planets, UPI reported.