This Week’s Sky at a Glance, 2019 July 6 – 13 ~by Curt Nason
Although Jupiter appears to be in the constellation Scorpius this summer, it is actually within the official borders of Ophiuchus the Serpent Bearer. By being in the constellation I mean passing in front of it. The stars are much farther than the planets, but how much farther? Neptune is the most distant planet from the Sun, about six times farther than Jupiter and 30 times farther than Earth. Sunlight takes 4.2 hours to reach Neptune but 4.2 years to reach the closest star, Proxima Centauri.
Rasalhague, the brightest star of Ophiuchus and which marks his head, is 49 light years away, while the one at his waist is about ten times farther. Rasalhague is closer to us than it is to some of the other stars that form the constellation. The constellation shapes are a matter of perspective but they will look the same from Neptune as they do from Earth.
Centuries ago the area where Jupiter currently resides was shared by Scorpius and Ophiuchus. When the constellation borders were set by the International Astronomical Union in 1930 this area was designated for Ophiuchus and, since the ecliptic runs through here, it became the 13th constellation of the zodiac. But don’t expect to find it in the daily horoscope.
This Week in the Solar System
Saturday’s sunrise in Moncton is at 5:35 am and sunset will occur at 9:12 pm, giving 15 hours, 37 minutes of daylight (5:43 am and 9:14 pm in Saint John). Next Saturday the Sun will rise at 5:40 am and set at 9:08 pm, giving 15 hours, 28 minutes of daylight (5:48 am and 9:10 pm in Saint John).
The Moon is at first quarter on Tuesday, giving great views through binoculars or a telescope all week. Jupiter is at its highest and best for observing in late evening, and telescope users might see its Red Spot around 11 pm on Thursday. Saturn reaches opposition on Tuesday and will be in the evening sky after sunset throughout the summer. Mercury and Mars are very low in the west after sunset, while Venus is very low in the east before sunrise.
Questions? Contact Curt Nason.