This Week’s Sky at a Glance, July 1 – July 8 ~by Curt Nason
Saturn is in the constellation Ophiuchus the Serpent Bearer this summer; “in” meaning in the same direction. The stars are much farther than the planets, but how much farther? Neptune is the most distant planet from the Sun, about three times farther than Saturn and 30 times farther than Earth. Sunlight takes 4.2 hours to reach Neptune and 4.2 years to reach the closest star, Proxima Centauri. Stand on one leg* while you read this article, and then try to imagine continuing for 4.2 hours. Doing that for 4.2 years is as incomprehensible as picturing a distance of 4.2 light years.
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. We are closer to Rasalhague than some of the stars that form the constellation. The constellation shapes are a matter of perspective but they will look the same from Saturn’s moons as they do from Earth.
Centuries ago the area where Saturn 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 5:32 am and sunset will occur at 9:13 pm, giving 15 hours, 41 minutes of daylight (5:40 am and 9:15 pm in Saint John). Next Saturday the Sun will rise at 5:36 am and set at 9:11 pm, giving 15 hours, 35 minutes of daylight (5:45 am and 9:13 pm in Saint John). Earth is at aphelion, its greatest distance from the Sun for the year at 152, 092,504 kilometres, around suppertime on Monday. Don’t bother putting on a sweater.
The Moon is at first quarter and near Jupiter on June 30, giving great views for holiday partiers who are fortunate enough to have clear skies this weekend. The waxing gibbous Moon is near Saturn on Thursday. On Wednesday, those with a telescope might catch Jupiter’s moon Europa playing “now you see me, now you don’t.” At 10:43 pm it starts emerging from behind Jupiter, only to disappear into the planet’s shadow four minutes later. Saturn’s rings are on display in a scope all evening, and in steady binoculars it will look somewhat elongated. Mercury sets an hour after sunset midweek but you will likely need binoculars to locate it. Venus rises two and a half hours before the Sun and dominates the morning sky with its brilliance.
The Saint John Astronomy Club meets on Saturday, July 8 at 7 pm in the Rockwood Park Interpretation Centre. All are welcome.
Questions? Contact Curt Nason at nasonc@nbnet.nb.ca.
*I am not responsible for any physical or emotional damage resulting from doing this. My lawyer tells me I do have a leg to stand on.