Exo-planet which shouldn't be there

[MargaritaMc]

THE UNIVERSITY OF ARIZONA
Department of Astronomy

December 5, 2013

The discovery of a giant planet orbiting its star at 650 times the average Earth-Sun distance has astronomers puzzled over how such a strange system came to be.

... Weighing in at 11 times Jupiter’s mass and orbiting its star at 650 times the average Earth-Sun distance, planet HD 106906 b is unlike anything in our own Solar System and throws a wrench in planet formation theories.

"This system is especially fascinating because no model of either planet or star formation fully explains what we see," said Vanessa Bailey, who led the research. Bailey is a fifth-year graduate student in the UA's Department of Astronomy.

... “Every new directly detected planet pushes our understanding of how and where planets can form," said co-investigator Tiffany Meshkat, a graduate student at Leiden Observatory in the Netherlands. "This planet discovery is particularly exciting because it is in orbit so far from its parent star. This leads to many intriguing questions about its formation history and composition. Discoveries like HD 106906 b provide us with a deeper understanding of the diversity of other planetary systems.

The research paper, “HD 106906 b: A Planetary-mass Companion Outside a Massive Debris Disk,” has been accepted for publication in The Astrophysical Journal Letters and will appear in a future issue.

Full article and graphics at:
http://uanews.org/story/ua-astronomers- ... t-be-there

M

[rstevenson]

Very interesting article. My first impression was that this must be a binary pair where there wasn't quite enough material for the second star to form, and indeed the authors of the forthcoming paper mention that. But they say our current models of planet and star formation don't allow such a thing. And that leaves me wondering, why not? I can imagine a model constraining what happens close in to a star like the Sun, because that's a system we understand well. But we're only just beginning to get a grasp on other systems, so surely our models shouldn't be so constraining yet.

Rob

[MargaritaMc]

Yes, our model has, inevitably, been drawn from a sample of one...

M