Countdowns

A brief look at how each American president helped shape and steer American activities in space.

Here is a guide to when certain planets will appear brightest and most visible in the 2021 night sky, including a dazzling Venus display at the year's end!

Here are the 10 most noteworthy sky events — including meteor showers and eclipses — that will take place in 2021.

The Mercury program launched the first Americans into space, four on suborbital flights, and two who orbited the Earth.

From having a day longer than its year to its wind speeds faster than tornadoes, Venus is odd.

Earth has been sending probes to Mars for decades, and some missions are especially awe-inspiring.

Humans have sent many missions, both manned and robotic, beyond our planet to explore our neighboring celestial bodies.

Apollo 13 was NASA's third moon-landing mission, but the astronauts never made it to the lunar surface. Here are the events that transpired.

This year's best meteor shower might be the Geminids in December, but if you don't want to skywatch in the cold, the summertime Perseids will also put on a show.

With "Star Wars: The Rise of Skywalker" here and the promise of more plot twists and turns just days away, we look back at the best we’ve ever seen in the "Star Wars" movie franchise.

A rundown of some of the biggest spacecraft to smash into Earth beyond their operators' control.

The annual Perseid meteor shower peaks every August and is often the most dazzling meteor display of the year.

NASA's Apollo program put the first humans on the moon. See how the missions flew in this photo tour.