Avid skywatchers had a chance to witness tonight’s close pairing between Jupiter and the First Quarter Moon — a nice sky event that kicked off the celebration of the National Astronomy Week 2013 in the Philippines. If you look closely at Jupiter in this image, you’ll also see a hint of its 4 Galilean moons.
During the closest approach, Jupiter and the Moon were 0.5 degree apart. For comparison, the angle covered by the diameter of the full moon is about 31 arcmin or 0.5 degree.
Astronomers use angular measurements to describe the apparent size of an object, or the distance between them. Knowing how to measure angular distance is an essential skill to finding your way around the sky.