Sun rises at 5:41am
Sun sets at 6:52pm
Moon phase: first quarter, waxing crescent
Moon rises: 9:33am, Saturday
Moon sets: 10:32pm, Saturday
This weekend, let’s keep gazing northward, this time with our goal of locating the Northern Crown. Also called Corona Borealis, you will find it medium high in the northern sky, between two bright stars: the slightly orange star Arcturus (in the constellation Bootes) and the blue-white star Vega (in the constellation Lyra).
Having trouble telling the colours of stars? They all look white to you? This is something that comes slowly if you keep studying the stars with eyes wide open, the subtle nuances become more and more noticeable over subsequent nights, weeks, months and years of careful observations. Don’t give up hope; keep trying and one night you will see the faint red light of Mars, the orange-ness of Arcturus and the blue-white of Vega or Saturn.
The Northern Crown looks faint, but on a dark and moonless night, you can pick it out; it looks like a half circle. The brightest star in the crown itself is called Gemma, a Latin word meaning the gem in the crown, but this same star is known to the Arabic stargazers as Alphecca, which in their language means the brightest one in the dish! Modern scientists know this is a very special star because it’s actually a binary system, that is, two stars orbiting around each other (this is only detectable with a strong professional level telescope). These two stars are, from our vantage point, very close together and they pass in front of each other every 17.4 days! Check the image provided for an artist’s impression of a binary star system similar to that of Gemma.
As you are looking northward, also keep track of our North Star, low on the horizon, and its two close companions the Big Dipper and the Little Dipper. The North Star is the only celestial body that doesn’t change its position in the sky, it is always there and all the other stars and the sun and moon rotate around it. The provided time lapse photograph shows this with amazing clarity.
Thank you for keeping up with the Night Sky articles. If you are out later on in the week, each star rises about four minutes earlier each day than written here, and the moon rises 50 minutes later. Night Sky is researched and compiled by Lisa Davis-Burnett. Earthsky.org is a key resource for information and images. Questions or comments? Email [email protected]