What does your nighttime sky look like? Are you observing light pollution in your sky?

This simulation will help you visualize the effects of light pollution on your ability to see faint stars in the night sky. To get started, click your location on the map, below, left. Then choose which constellation you will be observing (note that Crux can only be seen in the southern latitudes).

Now you are ready to explore the effects of light pollution. The gradient that runs along the bottom of the star chart represents varying levels of artificial light outside. As you run your mouse along the strip, you’ll see numbers appear. These represent the limiting magnitude that results from a given level of light pollution. The darker the sky, the greater the magnitude. Click a number to see how many stars you can see in the sky for that limiting magnitude.

Note: the field of view of the first 4 Magnitude Charts below is 100 degrees which is the same in length as 10 closed fists at arm’s length in the direction of Leo. The field of view of the last 4 Magnitude Charts is 50 degrees which is the same in length as 5 closed fists at arm’s length in the direction of Leo.

Have fun exploring!

Constellation: Orion    Latitude: 30 North    Magnitude limit: 4   

world map Latitude: 60 North Latitude: 50 North Latitude: 40 North Latitude: 30 North Latitude: 20 North Latitude: 10 North Latitude: Equator Latitude: 10 South Latitude: 20 South Latitude: 30 South Latitude: 40 South Latitude: 50 South

Choose a magnitude:
0 1 2 3 4 5 6 7

Choose a constellation:
Orion Leo Crux

Field of View

Adapted from http://answers.askkids.com/Weird_Science/what_is_field_of_view:

The field of view is a term used to describe what something is seeing at any moment in time. While humans have about 180 degree field of view, some birds and insects have almost 360 degree field of view. For the Globe at Night magnitude charts, it is the angular view shown by the chart. You can find more information here: http://en.wikipedia.org/wiki/Field_of_view