Archive
10/19/2021 – Ephemeris – Introducing the DART mission
This is Bob Moler with Ephemeris for Tuesday, October 19th. Today the Sun will be up for 10 hours and 47 minutes, setting at 6:50, and it will rise tomorrow at 8:05. The Moon, 1 day before full, will set at 7:54 tomorrow morning.
Last Saturday morning, the Lucy mission to Jupiter’s Trojan Asteroids was launched. These asteroids are forever locked in Jupiter’s orbit and will never be a hazard to the Earth. Next month, NASA will hopefully launch a mission to a much closer asteroid Didymos, which is considered a potentially hazardous asteroid. The asteroid has a diameter of a bit less than a half mile (780 meters). It also has a satellite named Dimorphos, which has acquired the nickname Didymoon, 520 feet (160 meters) in diameter. The mission called DART for Double Asteroid Redirection Test will see how the impact of a spacecraft hitting the small Didymoon will affect its orbit around the larger asteroid.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT-4 hours). They may be different for your location.