Saturday: “Lately, I’ve been, I’ve been losing sleep. Dreaming about the things that we could be. But baby, I’ve been, I’ve been praying hard, said no more counting dollars. We’ll be counting 9,096 stars, yeah we’ll be counting 9,096 stars.” Luckily, artistic judgment prevailed over scientific precision in the OneRepublic hit “Counting Stars”. According to the Yale Bright Star Catalog, there are 9,096 stars visible to the naked eye across the entire sky if you are observing from a very dark site. In the northern United States, where a part of the sky is never visible, that number drops to about 6,500. In the middle of a small city at mid-latitudes, like Ellensburg, that number drops to a few hundred. No wonder someone has been losing sleep. Learn more about the star count at http://goo.gl/nt8d80.
Sunday: Jupiter is one fist held upright and at arm’s length above the east- southeast at 5:35 a.m. Saturn is about a fist and a half to the upper right of Jupiter.
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: Astronomers are often fascinated with large objects. Planets that could hold 1000 Earths (Jupiter). Stars that would fill up the entire inner Solar System (Betelgeuse). Galaxies with 400 billion stars (Milky Way). But what about the smallest objects? One of the smallest stars is Proxima Centauri, the closest known star other than our Sun. It is about 12% of the mass of the Sun. Three years ago, astronomers announced the discovery of an Earth-sized planet orbiting Proxima Centauri indicating that even very small stars can have planets. The smallest theoretically possible star would be about 7.5% of the mass of the Sun. Any smaller and it could not support the nuclear reactions characteristic of stars. For more on small stars, go to http://goo.gl/EHBdOX.
Wednesday: In this busy world, it is important to know what time it is. We have many devices that give us the time. A phone. A computer. A watch. But who has time to build a phone, computer or even a watch. Not you. But everyone has enough time to build a simple Sun Clock. All you need is a pencil, a compass and a print out of the clock template. Go to https://www.exploratorium.edu/science_explorer/sunclock.html for more information.
Thursday: The Lyrid meteor shower peaks on Tuesday. But there will be increased meteor activity in the vicinity of the constellation Lyra until then. The meteors appear to come from a point to the right of the bright bluish star Vega in the constellation Lyra the lyre. This point is about three fists held upright and at arm’s length above the east-northeast horizon at midnight and close to straight overhead near dawn. Go to https://earthsky.org/?p=158735 for more information.
Friday: Mars is less than a half a fist to the upper left of the Moon at 10:00 p.m. Even next to the crescent Moon, Mars will be easy to see. Give yourself an added challenge and try to find Mars during the day. First find the Moon at 7:00 p.m., about five fists above the southwest horizon. Then hold your fist up so the bottom of your fist is against the upper left portion of the Moon. Mars will be near the middle of your fist. If you need help finding it, first use binoculars. Orient your binoculars so the Moon is in the lower right hand portion. Mars will be in the upper left or just outside the upper left of your field of view. Once you find it with binoculars, lower your binoculars while looking in the direction of Mars. For information on how to photograph Mars and the Moon, as well as a place where you can upload your Mars and Moon photo, go to https://my.astronomerswithoutborders.org/programs/global-astronomy-month/mars-moon.
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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