What is the surface of a comet like? That's one of the main questions that motivated Philae's mission to the surface of comet 67P/Churyumov-Gerasimenko. We now know the comet has a rigid crust about 10 to 50 centimeters thick, below which the comet is much more fluffy.
Three years ago, on October 19, 2014, comet C/2013 A1 Siding Spring passed within 138,000 kilometers of Mars. At the 2017 meeting of the Division for Planetary Sciences of the American Astronomical Society, we heard a progress report on Mars orbiter imaging of the comet's nucleus.
2016 marks the 25th anniversary of the creation of what has become one of the primary venues for the publication of research in planetary science: the Journal of Geophysical Research: Planets. This occasion is a good opportunity to look back at what we have learned in this era of expanded exploration and to try to take a peek at the future.
Just over a month ago the European Space Agency’s Rosetta spacecraft finished its mission by spectacularly diving into the comet 67P/Churyumov-Gerasimenko. How did it observations influence and alter our ideas about the typical formation and lifetime of a comet?
The Rosetta mission will end tomorrow when the spacecraft impacts the comet. ESA took advantage of the presence of hundreds of members of the media to put on a showcase of Rosetta science. If there’s one thing I learned today from all the science presentations, it’s this: Rosetta data will be informing scientific work for decades to come.
The European Space Agency has shared plans for the end of the Rosetta mission scheduled for September 30, just three weeks from now. The landing site will be located on the "head" of the comet, next to a prominent pit now named Deir el-Medina.
Ever since its landing, Philae has been elusive. It went silent just three days later and never returned any more science data, though it made brief contact with the orbiter last summer. Now, just a month until the planned end of the Rosetta mission, the orbiter has finally located the lander in a stunning high-resolution view of the surface.