Live coverage of the countdown and launch of a Proton rocket with Europe’s ExoMars Trace Gas Orbiter and the Schiaparelli entry, descent and landing demonstrator module to Mars. Text updates will appear automatically below; there is no need to reload the page. Follow us on Twitter.
Where did the two natural satellites of Mars, Phobos and Deimos, come from? For a long time, their shape suggested that they were captured asteroids. However, the shape and course of their orbits contradict this hypothesis. Two independent and complementary studies now provide an answer: these satellites formed from the debris of a gigantic collision between Mars and a protoplanet one-third its size.
This NASA/ESA Hubble Space Telescope image shows the globular cluster NGC 1854, a gathering of white and blue stars in the southern constellation of Dorado. NGC 1854 is located about 135,000 light-years away, in the Large Magellanic Cloud (LMC), one of our closest cosmic neighbours and a satellite galaxy of the Milky Way.