Astronomers are watching a giant planet form for the first time, thanks to rare images captured by the Hubble Telescope.
The new Jupiter-sized planet, which is forming around a young star system 370 light-years away from Earth, is one of only a handful of exoplanets to have been directly imaged, and the first that NASA has been able to witness actively growing.
Named PDS 70b after its host star PDS 70, at a mere five million years old the planet is little more than a baby in space terms, and is believed to be ‘the youngest bona fide planet Hubble has ever directly imaged,’ according to Yifan Zhou, a postdoctoral astronomy fellow at the University of Texas, Austin, who led processing of the images.
NASA/European Space Agency
The Hubble Telescope’s ability to capture UV light is helping astronomers estimate how fast the planet is gaining mass by siphoning extremely hot gas and dust material from its solar system.
As a result, PDS 70b is providing NASA with a unique opportunity to analyse first-hand how a giant planet comes to be.
In a press release, UT Austin astronomer Brendan Bowler said:
We just don’t know very much about how giant planets grow.
This planetary system gives us the first opportunity to witness material falling onto a planet. Our results open up a new area for this research.
European Southern Observatory Very Large Telescope
In research published this month in The Astronomical Journal, Zhou and his team estimate that over its five million year lifespan, PDS 70b has gained roughly five times the mass of Jupiter, but its rate of growth is currently slowing down, leading the team analysing the planet to believe it is currently in the ‘tail end’ of its formation.
Of course, capturing a newly-formed planet dozens of light-years away doesn’t come without its challenges. According to Zhou, processing the images required a painstaking effort to isolate the light emitted from the planet from the glare of its parent star, which is an estimated 3,000 times brighter. However as a result of this work, the Hubble Telescope is now capable of observing planets five times closer to their host star than it was previously.
‘Thirty-one years after launch, we’re still finding new ways to use Hubble,’ said Bowler. ‘Yifan’s observing strategy and post-processing technique will open new windows… with future observations, we could potentially discover when the majority of the gas and dust falls onto their planets and if it does so at a constant rate’