This month look for the star Alkaid, the star at the end of the Big Dipper’s handle. Astronomers refer to Alkaid as Eta Ursae Majoris and in Arabic the name means “the leader”. Its name is a reference to the star representing the lead daughter (the three stars of the handle are sisters) at a funeral bier. If you know someone who is 104 years old this year, then Alkaid is his or her birthday star. The light of Alkaid you see tonight left in 1910.

Alkaid is a hot star. It’s about four times hotter then the sun and 700 times brighter. It’s hotter and brighter because it has a mass six times greater than our sun’s. The star’s greater mass is crushing its core with a force greater than the sun’s force. That extra compression heats up the core and increases its rate of fusion. On the down side, the star will burn out far sooner than our sun.

The Big Dipper is not a constellation (a pattern of stars officially recognized by professional astronomers). It’s an asterism or popular pattern of stars. The Big Dipper is actually part of a much larger constellation called Ursa Major, the Big Bear. The dipper portion of Ursa Major represents just the bear’s body and a very long tail. The rest of Ursa Major is fainter and is not as well known. However, in dark skies you can make out three legs, head, and snout of the bear.

June Overview
● The length of the day stops getting longer by the 21st of the month. Our day in Idaho lasts13 hours and 17 minutes on the first and is only 21 minutes longer on the 30th. For the rest of the year, the nights begin growing longer at the expense of the length of the day.
● A thin crescent moon is visible on the night of the 1st. In binoculars, you should be able to see Earthshine. A second opportunity to observe earthshine occurs in the morning starting the 22nd as the moon approaches Venus.
● Venus remains very low in the east. You’ll need to look an hour before sunrise (in other words, around 5:00 AM) to see it.
● Mars is located in the southwest after dark and appears as a yellow-orange star. The moon makes a close passage to the planet on the 7th.
● This is your last month to observe Jupiter in the evening. Look for the bright planet low in the west-northwest. The moon appears close to Jupiter on the 1st.
● June is Saturn’s month. The pale yellow-white planet appears in the southern sky after darkness sets. The moon passes close to Saturn and the wide double star Zubenelgenubi on the 9th.
● Summer begins on the 21st at 4:51 AM.