A giant gas planet is believed to be the cause of the regular eclipses experienced by PDS 110, a young star located more than 1,000 light-years away in the constellation of Orion.
The exoplanet is estimated to have about 50 times the mass of Jupiter and is likely surrounded by a disk of debris that extends for at least 45 million kilometers (28 million miles). Astronomers have observed two eclipses, where about 30 percent of the light of the star was blocked. Each eclipse lasted about 25 days, so researchers believe a ringed planet is the best explanation. The study is due to be published in the Monthly Notices of the Royal Astronomical Society.
PDS 110 is an intermediate mass star, slightly larger than our Sun but much younger at only 10 million years old. The team used data from the Wide Angle Search for Planets (WASP) and the Kilodegree Extremely Little Telescope (KELT) to understand exactly what's going on.
“We found a hint that this was an interesting object in data from the WASP survey,” lead author Hugh Osborn, from the University of Warwick, said in a statement. “But it wasn’t until we found a second, almost identical eclipse in the KELT survey data that we knew we had something special.”
From the data, they estimated that the eclipse happens every 2.5 years, with one taking place in November 2008 and a second one in January 2011. Both eclipses looked remarkably similar, hence the suggestion they were caused by the same object, which is believed to be located twice as far from the star as our planet is from the Sun.
“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,” co-author and Leiden astronomer Matthew Kenworthy added.
The next eclipse is expected in September this year. The star is bright enough to be visible even with smaller instruments, so amateur astronomers should try having a look in that direction later in the summer to see if researchers are right about their hypothesis.
“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," added Hugh Oborn.
If this is confirmed, it could also help explain Tabby’s star. Recently, a ringed planet and asteroids have been proposed to explain its unusual dips in light.