For the first time ever, a team of researchers from University of Arizona has captured the photo of a baby planet being born. The birth of a new planet took place near a young star known as LkCa 15 which is located 450 light years away from Earth.
Of the roughly 2,000 known exoplanets previously spotted and confirmed outside our Solar System, only one has been observed shining strongly at a particular wavelength that betrays the presence of glowing hydrogen. Science reports that at a distance like that, hydrogen would likely only be heated that strongly when accreting onto a growing planet. The findings were published in the journal Nature.
“This is the first time that we’ve imaged a planet that we can say is still forming,” says Steph Sallum, a UA graduate student, who led the research with Kate Follette, a former UA graduate student.
LkCa 15 is surrounded by a special kind of protoplanetary disk that contains an inner clearing, or gap. Protoplanetary disks form around young stars using the debris left over from the star’s formation. Researchers suspect that by sweeping up the dust and debris – as the material falls onto the planets instead of staying in the disk or falling onto the star – planets are formed inside what is called protoplanetary disk. An inner clearing (gap) is then cleared in which the planets can reside.
These planetary findings were only possible because of the very specialized techniques and instruments the researchers developed, which include the Large Binocular Telescope, or LBT, the world’s largest telescope, located on Arizona’s Mount Graham, and the UA’s Magellan Telescope and its Adaptive Optics System, MagAO, located in Chile.
Atmospheric turbulence, the mixing of hot and cold air, makes it difficult to capture sharp images of distant objects. “When you look through the Earth’s atmosphere, what you’re seeing is cold and hot air mixing in a turbulent way that makes stars shimmer,” says Laird Close, UA astronomy professor and Follette’s graduate adviser, in a statement.
“To a big telescope, it’s a fairly dramatic thing. You see a horrible-looking image, but it’s the same phenomenon that makes city lights and stars twinkle.”
Getting the infrared images of LkCa 15 was only possible because of the Large Binocular Telescope adaptive optics system and a novel imaging technique. Close and Follette used Magellan’s adaptive optics system MagAO to independently corroborate these planetary findings.
Below is the photographic evidence of the birth of a new planet. It shows a composite where blue represents the MagAO data taken at H-alpha, and green and red show the LBT data taken at Ks and L’ bands. The greyscale is a previously published millimeter image of the disk.
“Results like this have only been made possible with the application of a lot of very advanced new technology to the business of imaging the stars,” says professor Peter Tuthill of the University of Sydney and one of the study’s co-authors, “and it’s really great to see them yielding such impressive results.”
Researchers hope their findingS will help astronomers refine their models of how solar systems and planets grow and evolve.
[Hat Tip: The University of Arizona, Accreting protoplanets in the LkCa 15 transition disk; Image: Stephanie Sallum]