Astronomers have made a prediction: On Tuesday morning, Nov. 19th, sky watchers in Europe and North America will see hundreds or thousands of meteors streak across the sky during the annual Leonid meteor shower. A dazzling show!

But which is it? Hundreds of meteors? ... or thousands?

You be the judge!

If you can count, you can help NASA decide whose predictions are correct.

Before you rush outside to start counting, however, there are a few procedures we need review to ensure that the counts are scientifically meaningful. The number of meteors you see depends on the light pollution in your area, the altitude of the shower's radiant, whether or not the moon is up, etc. All these need to be recorded so we can make sense of the observations and compare results from different observers.
Place a reclining chair (a lawn chair is fine) in a dark site with an open view of the sky. Dress warmly! You will also need a dim, red-filtered flashlight and a watch. You can make notes with a notebook and a pencil, but a tape recorder is even better. The recorder will allow you to dictate notes in the dark without taking your eyes off the sky. Before you start real observing, give your eyes ten minutes to adjust to the dark.

The full moon will be out on Nov. 19th. Try not to stare at it--it will ruin your night vision. Instead, look away from the moon toward a darker patch of sky.

Each time you see a meteor, make a check mark on your notepad or a comment on the voice recorder. Every ten minutes note the time. We've provided a printable form that might come in handy for making the meteor counts.

For your counts to be meaningful it is absolutely necessary to establish the "limiting magnitude" of your night sky. In other words, what is the dimmest star you can see? One way to check your limiting magnitude is to look at the constellation Leo. The diagram below shows the magnitudes of twelve stars in that constellation.

Done counting? Then it's time to submit your data. Click on the links below to add your counts to the NASA database: