Using satellite-tracking software, you should be able to plot the path and the time of passing of a current Space Shuttle mission, the Mir Space Station, or other satellites against the evening stars. Mir is a good satellite to identify because it is continuously circling the Earth, and its track takes passes over our viewing area.

Use information from SatPasses to duplicate the following scenario in the classroom.

This evening at 6:57 p.m., Thursday, September 12, NASA is planning to launch the Space Shuttle Discovery (STS-48). What makes this launch special for those of us in Maine is that it is being launched close to sunset and that it will have a fairly high angle of inclination (57 degrees, which is the angle formed by the path of the shuttle and the equator). If all goes well with the launch and the weather is cooperative, we might be able to spot the Shuttle this evening...Here's how.

First, you'll need to find a clear spot to view the northwest to northeast sky. You should have an unobstructed view of the Big Dipper. Avoid all outside lights if possible. Go outside about fifteen minutes early to locate the Big Dipper and adjust your night vision. Here's what you're looking to see.

Follow the two stars that make up the right edge of the Big Dipper. This will lead you directly to the North Star. The North Star is the brightest star in the area and is also the tail star of the Little Dipper. Why is the North Star important? First, it will tell you that you are facing in the right direction. More importantly, the elevation of the North Star (angle between the horizon and the North Star) is exactly equal to our latitude, which is approximately 43.8 degrees North. You'll see from the enclosed information that the highest elevation of this particular Shuttle pass is 29 degrees, which tells us that the Shuttle will be passing below the North Star. Expect to first see the Shuttle while it is in the vicinity of the Big Dipper.

Here are some important numbers. Azimuth refers to compass bearing - 270 degrees is west, 360 degrees is north, 90 degrees is east, etc. Elevation is the angle formed by the horizon and the Shuttle.

Between 8:42 and 8:46, we should see the Shuttle moving from northwest to northeast in the vicinity of the Big Dipper. It will appear to be moving from your left to your right, and it will pass below the North Star by approximately 15 degrees.

Time Azimuth Elevation  
8:38 257 0 Shuttle is on the west horizon.
8:42 282 18 Shuttle is gaining elevation.
8:45 360 25 The best time to spot the Shuttle.

What will it look like? (Don't expect to see the astronauts waving to you from their windows.) It should look like a bright star moving across the sky.

Timely Travel

The Space Shuttle travels at five miles/second. How long will it take the astronauts to travel from San Francisco to the East Coast of the United States? To London? Around the world?


  • Satellite tracking software
  • Computer