Sunday June 21
Summer Solstice for 2015 occurred this morning at 09:39 PDT (12:38 pm EDT). At this time, the most direct rays of the sun fall on the northern-most position possible on Earth, at the Tropic Of Cancer. Summer officially began today. The most daylight of the year occurs, and daytime gets progressively shorter until the Winter Solstice in December.
Monday June 22
Morning deep-sky object today is NGC 6946, a beautiful face-on spiral galaxy with bright knots in its arms. It has the most recorded supernovae, so some call it the Fireworks Galaxy. At 2/3rds of a degree in angular size, it appears dimmer than its 9th magnitude, but in darker skies it is a great sight. Although close to the constellation Cepheus, it resides in Cygnus. See if you can also get NGC 6939, a nice open cluster of about the same size and a bit brighter, into the same field of view.
Tuesday June 23
This will help show what an asterism is. In the left panel, the constellation Ursa Major, the Great Bear, is shown. The right panel shows the asterism we know as the Big Dipper. The Big Dipper is a shape we recognize, made by stars, but is not a constellation. The Big Dipper asterism is part of Ursa Major.
Wednesday June 24
First Quarter Moon occurred this morning at 03:04. Here you see the moon in the constellation Virgo, forming a right angle with the constellation’s brightest star Spica, and Arcturus in Bootes above it.
Mercury also reached greatest elongation this afternoon at 16:23. It was visible this morning in Taurus in the eastern predawn skies. You can see it again tomorrow morning.
Thursday June 25
Moon targets are always fun, with lots of detail on the easiest of all objects to find.
Copernicus is a classic view. A well-defined circular crater 35 miles in diameter, with very steep and tortured slopes. It contains a smooth floor with a central crater featuring several peaks.
Reinhold is right on the terminator tonight. It is smaller than Copernicus but also has steep slopes. Watch the light move across it.
Then check out Bullialdus, also on the terminator. A 50mm refractor at minimum for these craters
Friday June 26
This evening see if you can find the constellation Canes Venatici, the Hunting Dogs. It has only two stars, Cor Caroli the brighter of the two, and Chara, the other “dog.” They follow The Great Bear, Ursa Major. Cor Caroli was named in 1660 by physician Charles Scarborough in honor of the King Charles of England, and means The Heart of Charles.
Of course, you should be watching Venus and Jupiter too, as they approach their conjunction on 30.
Saturday June 27
If you have a clear eastern horizon, try finding Mercury as the sky brightens. It will be next to Taurus’ brightest star Aldebaran. Equally bright Capella will be higher up nearby to the north.