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.
Mars today is a dynamic place. One visually dramatic sign of change on Mars is "mass wasting," more commonly known as "stuff falling downhill". Scientists presented the results of recent laboratory work on Mars mass wasting at last week's Lunar and Planetary Science Conference.
James Tuttle Keane is increasingly famous (among planetary scientists anyway) for his remarkable illustrated notes from conferences. Here's his work from the Division for Planetary Sciences meeting, illustrating both his own and others' research.
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.
The team reported two weeks ago that the first attempts at observing 2014 MU69 were unsuccessful. But in their third try, on July 17, astronomers in Argentina saw the telltale sign of MU69's presence: a stellar wink.
The third-largest object known beyond Neptune, 2007 OR10, has a moon. The discovery was reported in a poster by Gábor Marton, Csaba Kiss, and Thomas Mueller at the joint meeting of the European Planetary Science Congress and the Division for Planetary Sciences of the American Astronomical Society (DPS/EPSC) on Monday.
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 astronomy world is abuzz today because of ESA's announcement of the first release of data from the Gaia mission. Gaia is a five-year mission that will eventually measure the positions and motions of billions of stars; this first data release includes positions for 1.1 billion of them, and proper motions for 2 million.
Several readers have contacted me recently about reports that a group of international astronomers have detected a strong signal coming from a distant star that could be a sign of a high-technology civilization. Here’s my reaction: it’s interesting, but it’s definitely not the sign of an alien civilization—at least not yet.
What began as a tantalizing rumor has just become an astonishing fact. Today a group of thirty-one scientists announced the discovery of a terrestrial exoplanet orbiting Proxima Centauri. The discovery of this planet, Proxima Centauri b, is a huge breakthrough not just for astronomers but for all of us. Here’s why.
Martian gullies were in the spotlight last week thanks to a NASA press release stating they were "likely not formed by liquid water" based on spectral results. But how does this stack up against their morphology?