ALMA Captures the Best Image to Date of Planets Forming Around an Infant Star

Astronomers have officially captured the best image to date of planet formation around an infant star. The findings reveal a bit more about the evolution of planets, and also reveal the astounding capabilities of the Atacama Large Millimeter/submillimeter Array (ALMA).

The new image reveals the planet-forming disk around HL Tau, a sun-like star that's located about 450 light-years from Earth in the constellation Taurus. It reveals unprecedented features in this system, including multiple concentric rings separated by clearly defined gaps. These structures in particular suggest that planet formation is already well underway.

HL Tau itself is hidden in visible light behind a massive envelope of dust and gas. But since ALMA observes at much longer wavelengths, it was able to peer through the intervening clouds in order to examine the processes at the core.

All stars are thought to form within vast clouds of gas and dust that collapse under gravity. Over time, the dust particles surrounding the star stick together, growing into sand, pebbles and, over time, planets. Once these planetary bodies acquire enough mass, they reshape the disk around the star and form rings and gaps.

"This new and unexpected result provides and incredible view of the process of planet formation," said Tony Beasley, one of the researchers, in a news release. "Such clarity is essential to understand how our own solar system came to be and how planets form throughout the universe."

 In fact, the findings reveal a bit more about planet formation. This, in turn, shows that ALMA can be used to make even more discoveries.

"This is truly one of the most remarkable images ever seen at these wavelengths," said Crystal Brogan, NRAO astronomer. "The level of detail is so exquisite that it's even more impressive than many optical images. The fact that we can see planets being born will help us understand not only how planets form around other stars but also the origin of our own solar system."