Mars to lose its moon but gain a ring

摘要

In 20 to 40 million years, Mars's largest moon, Pho-bos, will likely shred and the pieces will form a ring around the planet, similar to the rings encircling Saturn and Jupiter. New research concludes that Phobos will not be able to resist the tidal forces that will pull it apart when it approaches Mars. Just as Earth's Moon pulls on our planet in different directions, which raises tides in the oceans, Mars tugs on different parts of Phobos. As Phobos approaches Mars, the tugs are enough to actually pull the moon apart, the research shows, because it is highly fractured, with lots of pores and rubble. The rubble would then form a ring around the planet.