The Celestial Sphere from Latitude 45° North

0900 Hours Sidereal Time

The sky from 45°N at 0900 hours sidereal time

This page contains a description of the stars, constellations, and deep-sky objects that can be seen in the sky at around 0900 hours sidereal time. It is assumed that the observer is located at approximately 45° latitude north.

To use the sky map, orient it so that the direction you are facing is at the bottom of the map. Zenith, the point directly overhead in the sky, is located at the centre of the map.

Looking North

The 'Big Dipper' or 'Plough' is almost perfectly upside-down high in the northern sky. This asterism is just a small part of the larger constellation Ursa Major. The star in the bend of the handle of the 'Big Dipper' is called Mizar and as a test of both seeing conditions and eyesight acuity, look for its faint companion Alcor. The two stars at the end of the bowl of the 'Big Dipper' point to the brightest star in Ursa Minor, second magnitude Polaris. Polaris is about 1° away from the north celestial pole so the entire sky seems to pivot around it. Long exposure photographs reveal the truth, however; Polaris itself is also making a tiny circle around the pole. The 'lozenge' of stars marking the head of Draco is starting to rise off of the ground. The body of the dragon can be found slithering between Ursa Major and Ursa Minor. Below Ursa Minor is the constellation Cepheus. His wife is Cassiopeia, the M-shaped constellation just to the west. Perseus is a little further around to the west and the bright star above it is Capella in the constellation Auriga.

Following the arc of the handle of the 'Big Dipper' leads to the bright star Arcturus in the east. It stands at the bottom of the kite- or ice cream cone-shaped figure Boötes. Between Boötes and the eastern horizon is a small semi-circle of stars called Corona Borealis.

Looking South

Spica, the brightest star in the otherwise faint zodiacal constellation Virgo, is also rising in the east. More conspicuous, however, is Leo high overhead. Regulus stands at the bottom of the 'Sickle' of Leo, looking like the dot at the bottom of a backward question mark. Just west of Leo is another member of the zodiac, Cancer. There are no bright stars to be found here but binoculars may reveal M44, Praesape or the Beehive Cluster.

The splendid winter constellations are heading for the western horizon. Just west of zenith are the brothers Castor and Pollux of Gemini. The bright star below this constellation is Procyon in Canis Minor. The true 'Dog Star' is further south. Sirius, the brightest star in Canis Major (and indeed in the night sky), is actually one of the closest stars to the Sun. Orion dominates the southwest. Red Betelgeuse can be found in the upper left hand corner of the hourglass-shaped figure with blue Rigel in the lower right hand corner. Betelgeuse, Procyon and Sirius make up an asterism called the 'Winter Triangle' which is every bit as dazzling as its summertime counterpart.

Taurus is backing away from the threatening Orion. The three belt stars of Orion point toward the bull's eye Aldebaran. The V of stars outlining the bull's head is the Hyades, an open cluster. M45, the Pleiades, also stands on this imaginary line from Orion. The Pleiades is another open cluster of young stars. When viewed with a small telescope, this cluster reveals traces of nebulosity around its stellar components.