For the first time, a planet has been seen and photographed while it is still in the process of forming around its star. A “baby planet” as it were, still in its infancy.
The gas giant planet, also known as a protoplanet (one which is still forming) is known as LkCa 15 b, orbiting the star LkCa 15, which is about 450 light-years from Earth. It was photographed using the Keck Observatory telescopes as part of a survey of 150 nearby young dusty stars, stars with protoplanetary disks of dust and gas surrounding them. It is inside these disks that new planets form, including those which formed in our own solar system. This star is only about 2 million years old, very young in cosmological terms.
LkCa 15 b, still quite hot, is inside a wide gap of clear space between the star and the outer dusty disk, surrounded by a cooler swath of dust and gas. It is believed that as new planets form, they clear away the space where they orbit as material continues to conglomerate together, resulting in gaps in the disk, similar to the gaps in Saturn’s rings.
“LkCa 15 b is the youngest planet ever found, about 5 times younger than the previous record holder,” said astronomer Adam Kraus of the University of Hawaii’s Institute for Astronomy. “This young gas giant is being built out of the dust and gas. In the past, you couldn’t measure this kind of phenomenon because it’s happening so close to the star. But, for the first time, we’ve been able to directly measure the planet itself as well as the dusty matter around it.”
Protoplanetary disks have been seen and photographed before, and are well known, but to be able now to photograph the relatively tiny and dim planets forming inside them is an exciting new breakthrough.
This article was first published on Examiner.com.