Comets travel at incredibly variable speeds, depending on where they are in their orbit. Here's a breakdown:

* At their farthest point from the Sun (aphelion): Comets are traveling at their slowest, often just a few kilometers per second.

* As they approach the Sun (perihelion): They speed up dramatically due to the Sun's gravitational pull. Some comets reach speeds of over 100 kilometers per second!

Here are some examples:

* Halley's Comet: Reaches speeds up to 70 kilometers per second at perihelion.

* Comet Hale-Bopp: Travelled at around 50 kilometers per second at perihelion.

Important Note: A comet's speed is not constant. It's continuously changing as it orbits the Sun, with the greatest changes occurring as it moves closer or farther from the Sun's gravity.