Astronomers have identified that the light from PDS 110 is regularly blocked by a large object — and they predict that these eclipses are caused by the orbit of a giant gas planet.
Artist’s impression of the giant exoplanet orbiting the star PDS 110. The planet, PDS 110b, has an estimated mass about 50 times that of Jupiter and is encircled by a ring of dust. Image credit: University of Warwick.
PDS 110 is a rare Fe/Ge-type star, a 10-million-year-old accreting intermediate-mass star.
Also known as HD 290380, IRAS 05209-0107 and 2MASS J05233100-0104237, the star is slightly larger than our Sun but has the same temperature.
PDS 110 is located in the constellation of Orion, approximately 1,125 light-years from Earth.
This distance makes PDS 110 consistent with being a member of the Orion OB1a association, the group of very young stars northwest of the Orion Belt stars.
Using data from the Wide Angle Search for Planets (WASP) and Kilodegree Extremely Little Telescope (KELT), an international team of astronomers analyzed 15 years of the PDS 110’s activity.
“We found a hint that this was an interesting object in data from the WASP survey, but it wasn’t until we found a second, almost identical eclipse in the KELT survey data that we knew we had something special,” said Hugh Osborn, a PhD student in the Astronomy and Astrophysics group at the University of Warwick, UK, and lead author of a new paper in the Monthly Notices of the Royal Astronomical Society (arXiv.org preprint) describing the discovery.
Osborn and co-authors discovered that every 808 days, the light from PDS 110 is reduced to 30% for about two to three weeks.
Two notable eclipses observed were in November 2008 and January 2011.
“What’s exciting is that during both eclipses we see the light from the star change rapidly, and that suggests that there are rings in the eclipsing object, but these rings are many times larger than the rings around Saturn,” said Dr. Matthew Kenworthy, an astronomer at Leiden Observatory.
The next eclipse event is predicted to take place in September 2017 and could be monitored by amateur and professional astronomers across the world.
“September’s eclipse will let us study the intricate structure around PDS 110 in detail for the first time, and hopefully prove that what we are seeing is a giant exoplanet and its moons in the process of formation,” Osborn said.
The astronomers suggest that there are moons could be forming in the habitable zone around PDS 110 — pointing to the possibility that life could thrive in this planetary system.
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H.P. Osborn et al. Periodic Eclipses of the Young Star PDS 110 Discovered with WASP and KELT Photometry. MNRAS, published online May 20, 2017; doi: 10.1093/mnras/stx1249
