WEBVTT 00:01.533 --> 00:07.433 position:10% line:85% size:80% (MUSIC) JOAN CARTAN-HANSEN, 00:07.433 --> 00:11.700 position:10% line:85% size:80% HOST: MARS HAS NOT ONE BUT TWO MOONS: PHOBOS AND DEIMOS. 00:11.700 --> 00:14.100 position:10% line:85% size:80% PHOBOS IS ABOUT 14 MILES ACROSS. 00:14.100 --> 00:18.433 position:10% line:85% size:80% IT ORBITS ONLY 37 HUNDRED MILES ABOVE THE SURFACE OF MARS AND 00:18.433 --> 00:21.333 position:10% line:85% size:80% ZIPS AROUND THE PLANET THREE TIMES A DAY. 00:21.333 --> 00:23.800 position:10% line:85% size:80% DEIMOS IS SMALLER AT ONLY ABOUT EIGHT MILES ACROSS. 00:23.800 --> 00:27.066 position:10% line:85% size:80% IT OBITS MORE THAN 12 THOUSAND MILES ABOUT THE SURFACE. 00:27.066 --> 00:30.333 position:10% line:85% size:80% AND TAKES ABOUT 30 HOURS TO TRAVEL AROUND MARS. 00:30.333 --> 00:32.166 position:10% line:85% size:80% BOTH LOOK MORE LIKE ASTEROIDS. 00:32.166 --> 00:34.700 position:10% line:85% size:80% THEY'RE SHAPED KIND OF LIKE LUMPY POTATOES AND HAVE LOTS OF 00:34.700 --> 00:36.266 position:10% line:85% size:80% CRATERS ON THEIR SURFACE. 00:36.266 --> 00:40.066 position:10% line:85% size:80% AND UNLIKE OUR MOON, THE MOONS AROUND MARS ARE NOT IN A STABLE 00:40.066 --> 00:41.533 position:10% line:85% size:80% ORBIT. 00:41.533 --> 00:44.433 position:10% line:85% size:80% PHOBOS IS SLOWLY SPIRALING INWARD TO THE SURFACE. 00:44.433 --> 00:48.166 position:10% line:85% size:80% SO WITHIN 50 MILLION YEARS, IT WILL EITHER COLLIDE WITH MARS OR 00:48.166 --> 00:50.633 position:10% line:85% size:80% BREAK APART INTO A RING OF RUBBLE. 00:50.633 --> 00:53.800 position:10% line:85% size:80% DEIMOS, ON THE OTHER HAND, IS SLOWLY DRIFTING AWAY FROM MARS. 00:53.800 --> 00:56.633 position:10% line:85% size:80% IT WILL EVENTUALLY JUST FLOAT OFF INTO SPACE. 00:56.633 --> 00:59.500 position:10% line:85% size:80% FOR MORE INFORMATION ABOUT MARS, CHECK OUT THE SCIENCE TREK 00:59.500 --> 01:00.266 position:10% line:85% size:80% WEBSITE. 01:00.266 --> 01:04.100 position:10% line:85% size:80% YOU'LL FIND IT AT IDAHOPTV.ORG/SCIENCE TREK