Sunday: Venus is a little more than a half a fist held upright and at arm's length above the west-northwestern horizon at 9:15 p.m. Because it is the bright point of light in the sky, it should be fairly easy to find. Mercury will be more challenging. It is about two finger-widths to the lower right of Venus, almost exactly a half a fist above the horizon. But it is more than 100 times dimmer than Venus, in the waxing crescent phase.
Monday: The questions who, what, where, and when can only be asked with a “W”. At 10:00 p.m., the W-shaped constellation Cassiopeia is two fists above the north-northeastern horizon. The middle star in the W was used as a navigation reference point during the early space missions. The American astronaut Gus Grissom nicknamed the star Navi, his middle name Ivan spelled backwards. After he died in the Apollo 1 fire, the star name was kept as a memorial.
Tuesday: The month of June is named after Juno, the queen of the Roman gods and the mythological protector of the Roman state. In ancient Rome, the month began when the crescent moon was first seen in the evening sky from Capitoline Hill in Rome. If we still started months this way, June would start on a different day each year. This year, the month would start in about a week and a half after the next New Moon. This morning, the Moon is in the waning gibbous phase, two fists above the southeastern horizon at 4:30 a.m. Juno’s husband, Jupiter, is a half a fist above the Moon at this time.
Wednesday: Cygnus the swan flies tonight. Deneb, the brightest star in the constellation, whose name means “tail” in Arabic, is about two and a half fists above the northeastern horizon at 10:00 p.m. Cygnus’ wings make a vertical line one half a fist to the right of Deneb. Its head, marked by the star Albireo, is two fists to the right of Deneb. While Deneb is at the tail of Cygnus, it is at the head of the line of bright stars. It is 160,000 times more luminous than the Sun making it one of the brightest stars in the galaxy. It does not dominate our night sky because it is 2,600 light years away, one of the farthest naked eye stars. If Deneb were 25 light years away, it would shine as bright as a crescent moon. Compare that to Vega, its fellow Summer Triangle star. Vega IS 25 light years away and certainly doesn’t rival the light of the crescent Moon. See for yourself by looking nearly four fists above the east-northeastern horizon at 10:00 p.m.
Thursday: Altair, the lowest star in the Summer Triangle, is one fist above due east at 10:15 p.m.
Friday: As the weather warms up, people start thinking about swimming in a nice cool body of water. Recently, astronomers have discovered evidence of an ocean about 20 miles beneath the surface of Saturn’s moon Enceladus. NASA’s Cassini probes measured variations in how the moon’s gravity pulled on the orbiting spacecraft. These variations can be explained by a large amount of liquid water under one section of the ice because liquid water is denser than an equal volume of ice. While you need a very large telescope to see Enceladus, you can easily see Saturn a half a fist above the southeast horizon at 1:00 a.m. They are both two and a half fists above the southern horizon at 4:30 a.m.
The positional information in this column about stars and planets is typically
accurate for the entire week. For up to date information about the night sky,
go to https://nightsky.jpl.nasa.gov/planner.cfm.
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