The northern sky’s two most prominent sky patterns – the constellation Cassiopeia the Queen and the Big Dipper – both circle around Polaris, the North Star, once a day. They are opposite each other – one on either side of the North Star.
The constellation Cassiopeia the Queen is easy to recognize in the northern sky, either in the evening or before dawn. This constellation is shaped like a W or M and contains five moderately bright stars. The distinctive shape of Cassiopeia makes her very noticeable among the stars of the northern sky.
And, of course, Ursa Major the Greater Bear – which contains the Big Dipper asterism – is one of the most famous of all star patterns. At nightfall this month, Cassiopeia shines high in the north while the Dipper lurks low. They are always on opposite sides of the North Star. From the southern half of the U.S., the Big Dipper is actually partially or totally beneath the horizon this month in the evening hours. North of about 40 degrees north latitude (the latitude of Denver, Colorado), the Big Dipper always stays above the horizon. Nonetheless, the Big Dipper’s proximity to the horizon may cause haze low in the sky or obstructions close to the horizon to obscure these stars in the evening at this time of year.
That’ll change as night passes, as the great carousel of stars wheels westward (counter-clockwise) around Polaris, the North Star. Polaris resides halfway between Cassiopeia and the Big Dipper, so these two star formations are like riders on opposite sides of a Ferris wheel. Looking northward, they rotate counter-clockwise around Polaris – the star that marks the sky’s north pole – once a day. Approximately every 12 hours, as Earth spins beneath the heavens, Cassiopeia and the Big Dipper trade places in the sky.
Thus, around 11 p.m. tonight, Cassiopeia circles directly west (left) of Polaris, whereas the Big Dipper sweeps to Polaris’ east (right). Before dawn tomorrow, the Big Dipper climbs right above the North Star, while Cassiopeia swings directly below.
Watch the celestial clock and its two great big hour hands – Cassiopeia and the Big Dipper – as they swing around the North Star every night!
Kudos! Almost every morning the first thing I do after turning on my computer is checking EarthSky to see what is happening that night.
What’s up with the moon?
My family and I were out for a drive lastnight when we noticed the moon on the horizon it looked to be much larger than normal so we pulled over to snap some photos.
Most scientists agree that the reason the moon looks bigger is purely in our minds. Our mind interprets the things we see in interesting ways. For instance, if you look at any door frame you can see that it is rectangular. But if you were to sketch the outline of the door frame from the angle that you are looking at it, most likely you would sketch a trapezoid. Your mind adjusts the door so that you perceive it as a rectangle from whatever angle you look at it. That theory is called shape constancy.
Basically i agree with what Sig said, but let me provide u with a context specific to the phenomenon u observed: So when the moon is low, we see it in the same field as objects on the ground, i.e. trees, buildings, etc. Since we know it is farther, our brain interprets this to mean that the moon is HUUUGE (which compared 2 any of those objects it really is). But when it is high in the sky, though in reality our eyes see it as the same size, since it is not next to the ground our brain isn’t comparing it to those objects, so it loses the frame of reference it had, making it perceptually not as big.
We just saw a huge dark arc around the moon with what looked like an aurora of sorts, with a beam of light projecting out into the sky (and a weaker beam from the moon to the lights). Never seen anything like it!
What did we see?
probably what u saw was an effect caused by the moon shining thru a high cloud deck, causing the “arc” and aurora (u were probably referring to an aureole, which also happens frequently happens with the sun). when moonlight “peeks” thru a gap in thicker clouds u can sometimes see the beam.
The moon is really, really, really odd tonight. It looks like a cup of tea. Some people are saying it is because it is closer to Mars than it has been in years..anyone?
nope. just that’s the moon’s phase, which makes it about half-full, like a half-full cup. absolutely nothing 2do with mars.
Coffee on the deck this a.m. w/ the same arc and aureole and beam of light shooting out the other side. Appears to be the same size arc (pretty big). Never seen anything like it!