Wednesday, May 1, 2024

The Ellensburg, WA sky for the week of May 4, 2024

Saturday: The Eta Aquarid meteor shower peaks just before dawn this weekend. Since this meteor shower has a broad peak range, you should start looking before dawn every morning this week. The moon is close to the new moon phase near the peak, meaning even dimmer meteors will be visible. Meteor showers are named after the constellation from which the meteors appear to originate. The meteors appear to come from a point in the constellation Aquarius near the star Eta. This point is about one fist held upright and at arm’s length above the east horizon at 4:00 a.m. The Eta Aquarid meteors slam into the Earth at about 40 miles per second. They often leave a long trail. The Eta Aquarid meteors are small rocks that have broken off Halley’s Comet. For more information about the Eta Aquarids, go to http://earthsky.org/?p=158833.

Sunday: Mother’s Day is next Sunday. What are you going to get her? Get her a Gem(ma). The star Gemma, also known as Alphekka, is the brightest star in the constellation Corona Borealis, the Northern Crown. Gemma, Latin for jewel, is the central gemstone for the crown. It is four fists above due east at 9:30 p.m.

Monday: It is often said that Earth is a water world because about 70% of the Earth’s surface is covered by water. What would it look like if all that water on the surface were gathered up into a ball? That “ball” would be about 700 km in diameter, less than half the diameter of the Moon. The Astronomy Picture of the day shows us right here https://apod.nasa.gov/apod/ap120515.html.

Tuesday: Give me an “M.” Give me a “3”. What does that spell? “M3.” “Big deal,” you say. It was a big deal to French comet hunter Charles Messier (pronounced Messy A). M3 was the 3rd comet look-alike that Messier cataloged in the late 1700s. M3 is a globular cluster, a cluster of over 100,000 stars that is 32,000 light years away. It is too dim to be seen with the naked eye but is fairly easy to find with binoculars. First find Arcturus five and a half fists above due southeast at 10:30 p.m. Move your binoculars up one binocular field of view so two stars of nearly identical brightness are in your field of view. When the top star is in the lower left part of your field of view, there should be a fuzzy patch near the center of your field of view. This is M3.

Wednesday: Saturn is one fist above the east-northeastern horizon at 4:45 a.m.

Thursday: Mars’ two small moons, Phobos and Deimos, are not visible in typical backyard telescopes. But they are an interesting study. The former view among astronomers was that both moons are captured asteroids. That makes sense given Mars’ proximity to the asteroid belt. But recent findings by European astronomers indicate that Phobos is very porous and made of material like the surface of Mars. This implies that Phobos may consist of chunks of Martian debris that was blasted off by numerous impacts and gravitationally bound together. Unfortunately, the Russian Phobos-Grunt probe launched late 2011 to collect material from Phobos crashed to Earth after malfunctioning. For more information about this recent model of Phobos’ formation, go to https://sci.esa.int/web/mars-express/-/31031-phobos. For more information about Mars, look a half a fist above the eastern horizon at 4:45 a.m.

Friday: This weekend, celebrate Mother’s Day with the big mom of the sky, Virgo. Ancient Greeks and Romans associated this portion of the sky with their own goddess of the harvest, either Demeter (Greeks) or Ceres (Roman). Demeter was the mother of Persephone and Ceres was the mother of Proserpina. According to myth, each of these daughters was abducted causing their mothers great grief. The first star in Virgo rises in the afternoon. Spica, the bright bluish star in the constellation rises at 7:00 p.m. and is three fists above the south-southeastern horizon at 10:00 p.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. All times are Pacific Time unless noted. 

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