Find Gemini, Cancer and Leo from The Big Dipper (The Plough)

The Zodiacal Sky:

Finding Gemini, Cancer & Leo

from The Big Dipper

by Martin J. Powell

The well-known asterism (star group) known as The Big Dipper (or The Plough) in Ursa Major (The Great Bear) can be used as a starting point to finding Gemini, Cancer and Leo in the night sky (provided these constellations are above the observer's horizon at the required time). Click on the accompanying thumbnail to see the full-size diagram (26 KB).

To find Leo, project the line between the stars Megrez ( Ursae Majoris) and Phekda ( Ursae Majoris) in a Southward direction until you reach the bright star Regulus ( Leonis) as indicated in the animation.

To find Gemini, project the diagonal line between Megrez and Merak ( Ursae Majoris) towards the South-west until you come across the two leading stars of The Twins, namely Castor ( Geminorum) and Pollux ( Geminorum).

Cancer can be found using the The Big Dipper or, alternatively, by using Gemini and Leo. Project the line formed by Alioth ( Ursae Majoris) and Phekda towards the South-west, into the 'dark' region of sky between Gemini and Leo; Cancer is located about half-way between Castor and Regulus.

Note that this method primarily applies to Northern hemisphere observers. Southern hemisphere observers can only use this method if they are situated North of latitude 28° South (The Big Dipper is not wholly visible at latitudes further South than this).

The lines pointing to Gemini, Cancer and Leo from The Big Dipper can also be seen in the form of an animation (1.2 MB).

Find Gemini, Cancer & Leo from The Big Dipper (Desktop Site)

^ Back to Top of Page

Site hosted by TSOHost