What's up in the Ellensburg, WA sky for the week of July 1, 2023

Saturday: Look straight up at midnight. The head of Draco the dragon will be looking straight down on you. The brightest star in the head is called Eltanin. If you wait for a VERY long time, Eltanin will be the brightest star in the entire night sky. Currently 154 light years away, it is moving towards Earth and will be only 28 light years away in about 1.3 million years, claiming the title as the brightest star.

Sunday: Recently, the Mars Curiosity rover made a comprehensive measurement of the organic carbon found in rocks on the Martian surface. It found more organic carbon in the Gale Crater rocks than in very low-life places on Earth such as the Atacama Desert in South America. This certainly does not prove there is life on Mars now. And it does not prove there was life on Mars in the past. But it definitely strengthens the argument for either. In the past, Gale Crater likely had water, chemical energy sources, low acidity, and other elements common in living organisms. Read more about the findings at https://www.nasa.gov/feature/goddard/2022/mars-total-organic-carbon. Find Mars a little more than one fist above the western horizon at 10:00 p.m. It is just to the upper left of very bright Venus. Regulus, the brightest star in the constellation Leo, is to the immediate upper left of Mars.

Monday: The July full moon is called the Buck Moon to signify the new antlers that form on the forehead of a buck this time of year. Officially, the July full moon is today at 4:30 a.m. Pacific Daylight Time. That means the moon will look full both Sunday and Monday nights. It will be visible nearly the entire night both nights.

Tuesday: Mizar is a star in the middle of the Big Dipper handle. Don’t confuse Mizar with its rhyming brother Izar in the constellation Bootes. Izar is also a binary star with about the same apparent brightness. And both were featured in different episodes of Star Trek. Izar was featured in the Star Trek episode “Whom Gods Destroy” from the original series. It is the base of Fleet Captain Garth, a former big shot in the federation and one of Kirk’s heroes before he went insane. Garth kidnaps Kirk and Spock before eventually being outsmarted. Mizar doesn’t play as big a role in its episode. It is the star of the home world of one of the alien species in The Next Generation episode “Allegiance”. Izar is one fist above the bright star Arcturus and five and a half fists above the west-southwestern horizon at 11:00 p.m. Mizar is five and a half fists above the west-northwestern horizon.

Wednesday: Being in a coma is a bad thing. Looking at the Coma Star Cluster is a good thing. The Coma Star Cluster is an open cluster of about 50 stars that takes up more space in the sky than 10 full Moons. It looks like a fuzzy patch with the naked eye. Binoculars reveal dozens of sparkling stars. A telescope actually diminishes from the spectacle because the cluster is so big and the telescope’s field of view is so small. The Coma Star Cluster is in the faint constellation Coma Berenices (ba-ron-ice’-ez) or Queen Berenice’s hair. Queen Berenice of Egypt cut off her beautiful hair as a sacrifice to the gods for the safe return of her husband Ptolemy III from battle. The Coma Star Cluster is about three fists above the western horizon at 11:00 p.m. 

Thursday: Hot enough for you? Don’t blame the Earth-Sun distance. Surprisingly, the overall temperature of the Earth is slightly higher in July, when the Earth is farthest from the Sun, than in January, when it is closest. That’s because in July, the Northern Hemisphere is tilted towards the Sun. (This is the real cause of the seasons.) The Northern Hemisphere has more land than the Southern Hemisphere. Thus, in July, the large amount of Northern Hemisphere land heats up the entire Earth about two degrees Celsius warmer than in January. In January, the watery Southern Hemisphere is tilted toward the Sun. But, water does not heat up as fast as land so the Earth is a few degrees cooler. The distance between the Earth and the Sun is its greatest today, 152.1 million kilometers. This is called aphelion from the Greek prefix “apo” meaning “apart” and Helios, the Greek god of the Sun.

Friday: Saturn is less than a half a fist to the right of the Moon at 4:30 a.m. They are three fists above the southern horizon. At this time, Jupiter is three fists above the eastern horizon.

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.