Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2015 January 29
Close Encounter with M44
Image Credit & Copyright: Carlo Dellarole, Andrea Demarchi
Explanation: On Monday, January 26, well-tracked
asteroid 2004 BL86 made its closest approach, a mere 1.2 million kilometers from our fair planet. That's about 3.1 times the Earth-Moon distance or 4 light-
seconds away. Moving quickly through Earth's night sky, it left this streak in a 40 minute long exposure on January 27 made from Piemonte, Italy. The remarkably pretty field of view includes
M44, also known as the Beehive or Praesepe star cluster in Cancer. Of course, its close encounter with M44 is only an apparent one, with the cluster nearly along the same line-of-sight to the
near-earth asteroid. The actual distance between star cluster and
asteroid is around 600 light-years. Still, the close approach to planet Earth allowed detailed radar imaging from NASA's Deep Space Network antenna at Goldstone, California and revealed the
asteroid to have its own moon.
