Explore the Universe: Double Stars
This Week's Targets and How to Find Them
- Waning Crescent (lunar phase)
- You'll have to get up early in the morning on September 15th. You can see it just west of the Sun after sunrise but you have to be careful not to look at the Sun itself!
- Petavius (lunar crater)
- Hard to find, lower right / eastern side of the moon under Fecunditatis. Has a little central peak that you might be able to see. It's in a row with 3 other craters of similar size, from top to bottom: Langrenus, Vendelinus, Petavius, Furnerius, so it's second from the bottom. Only visible Sept 2nd.
- Cleomedes (lunar crater)
- Just above Mare Crisium towards the north. First crater you can see when moving up from Mare Crisium. Only visible on Sept 3rd, but you might be able to see it on the 2nd as well.
- Cassiopeia (constellation)
- If you turn the summer triangle into an arrow where Deneb is the point and Vega and Altair are at the end of the arms, it points right at Cassiopeia which looks like an M or W. You could also follow the body of Cygnus which points directly at Cassiopeia. Visible all the time but best in fall/winter.
- Zeta Lyr (double star)
- Just so you know, almost all the stars in Lyra are double stars, so you'll have to be careful. This one is the star just south of Vega heading towards Altair. Visible until about January.
- Delta Lyr (double star)
- The star just south of Zeta Lyr heading towards Altair. Beautiful and colourful! Visible until about January.
- Nu Dra CORRECTED(double star)
- Follow the line formed by Vega and Altair north of Vega by 15 degrees (about the width of your hand in the "stop" gesture). You'll come across four stars in a lopsided square formation (the head of Draco, the dragon). Nu Dra (also known as Kuma) is the northwesternmost star, forming a right angle triangle with the two brightest stars. Visible all the time.
- 17/16 Dra (double star)
- Keep going past Nu Dra just under another fist's width to the next bright star. It's much dimmer, only mag 6. Visible all the time.
- Mars! (planet, optional)
- The Moon and Mars will be within 0.5º of each other at their closest in the evening on September 5th! They rise around 9:45pm and will be visible all night, so definitely get out there and catch them! Closest together around 11:30pm EDT.