Fri., August 3 5:37 7:57
Sat., August 4 5:38 7:56
Sun., August 5 5:39 7:55
Mon., August 6 5:40 7:53
Tues., August 7 5:41 7:52
Wed., August 8 5:42 7:51
Thurs., August 9 5:43 7:50
Fri., August 10 5:44 7:48
A gibbous moon dominates the evening sky this weekend and well into the coming week. The moon rises tonight soon after sunset. The moon is two days past full moon, and still a bright night-time object.
The moon spends the weekend moving through the zodiacal constellation Aquarius into Pisces.
The word “gibbous” draws the most interest of any astronomical term used in this column. Gibbous describes a phase when the size of the illuminated portion is greater than half, but not a full moon. The moon is full one day a month, but it is gibbous for several days on either side of the full moon.
The red planet Mars and the yellow planet Saturn form a triangle with the bright star Spica low in the southwestern sky after sunset. All three are in the zodiacal constellation Virgo. Can you tell them apart?
Mars is easy, with its reddish tint. Spica has a blueish tint and is closest to the horizon. In the nights ahead, the triangle will get smaller and smaller. The three will appear to form a line by midmonth and that will be short-lived.
For those who have been watching the three for weeks, note that both Saturn and Spica are slowly getting closer and closer to the western sky, while Mars appears to ride through the stars staying far from the horizon. It is moving in between Saturn and Spica. There is plenty of change ahead. As we get later in the year, Mars eventually will follow Saturn and Spica and slip into the evening twilight, to reappear months from now as a morning planet.