Site Glossary

A straight line matching a curve’s instantaneous slope at a point.

possible evidence of technological activity.

A measure of how hot a star's surface is.

Constant falling velocity reached when drag balances weight.

Distance travelled during a driver’s reaction time.

stretching or compression caused by differences in gravitational attraction.

The interval over which motion occurs.

The elapsed time between two events.

Total time between launch and landing.

study of astronomical objects and events that change over time.