A series of images taken with the Gemini Planet Imager (GPI) on the Gemini South telescope in Chile shows an extrasolar gas giant called Beta Pictoris b orbiting its parent star, Beta Pictoris. The images, captured between November 2013 and April 2015, show the exoplanet as it moves through 1.5 years of its 22-year orbital period.
“The images represent the most accurate measurements of the planet’s position ever made,” said Maxwell Millar-Blanchaer of the University of Toronto.
Beta Pictoris b is a gas giant approximately 7 times the mass of Jupiter, with an orbit roughly the diameter of Saturn’s.
It was discovered in November 2008 by Dr Anne-Marie Lagrange of the University Joseph Fourier and co-authors.
The planet orbits a neighboring star called Beta Pictoris, which lies 63 light-years from Earth and is estimated to be only 20 million years old.
The system includes exocomets, orbiting gas clouds, and an enormous debris disc.
Because Beta Pictoris b and the debris disk interact gravitationally, the system provides scientists with an ideal laboratory to test theories on the formation of planetary systems.
This is an artist’s impression of the young exoplanet Beta Pictoris b and its parent star. Image credit: ESO / L. Calçada / N. Risinger, skysurvey.org.
“We’re able to see both the disc and the planet at the same time,” said Millar-Blanchaer, who is the lead author of a paper published in the Astrophysical Journal (arXiv.org preprint) that describes observations of the Beta Pictoris system made with the GPI.
“With our combined knowledge of the disc and the planet, we’re really able to get a sense of the planetary system’s architecture and how everything interacts.”
“It’s fortunate that we caught Beta Pictoris b just as it was heading back – as seen from our vantage point – toward Beta Pictoris,” added co-author Dr Laurent Pueyo of the Space Telescope Science Institute in Baltimore, Maryland.
“This means we can make more observations before it gets too close to its parent star and that will allow us to measure its orbit even more precisely.”
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Maxwell A. Millar-Blanchaer et al. 2015. β Pictoris’ inner disk in polarized light and new orbital parameters for β Pictoris b. ApJ, 811, 18; doi: 10.1088/0004-637X/811/1/18
