Last year, the European Space Agency (ESA) successfully sent its Rosetta probe into orbit around a comet. Now, finally, scientists have published research on what they've concluded from images sent back from the spacecraft to Earth—and what they've found is that comet 67P is home to many, many sinkholes.
A study published in Nature this week explains that 18 "cometary pits" have been spotted on comet 67P's surface.
According to Reuters, some of the pits are very, very large: around 650 feet across and 590 feet. That means some are almost big enough to hold the Great Pyramid of Giza. Some of them are spewing jets of dust into the cosmos.
Most likely, the jet-spewing pits mean that the inside of the comet is rather volatile. Lead study author Jean-Baptiste Vincent explained to the Guardian: "Many comet formation models predict that under the surface they should be homogenous, the same throughout, but we show that this cannot be the case."
NASA's Paul Weissman told Reuters that "Finding the pits was a total surprise." Seems like space is full of pyramid-sized surprises these days.
Danielle Wiener-Bronner is a news reporter.