TRAPPIST-1e shows no signs of its first atmosphere, but hints of a secondary one remain. Liquid water could still be possible ...

The autumnal equinox arrives Monday, marking the start of the fall season for the Northern Hemisphere and the spring in the ...

But the best option is to stay on standard time all year. According to their study, doing this could prevent 300,000 cases of ...

Earth has a number of mini-moons and quasi-moons. Mini-moons are objects that orbit our planet. But they make for fickle fans: They tend to swing around Earth for only a matter of months. One example ...

The autumnal equinox, aka astronomical fall, is the specific moment determined by Earth’s tilt and its position during its ...

This article was originally published on mentalfloss.com as Autumn Equinox: The Science Behind the First Day of Fall.

Here's what happens as the direct rays of the sun slip south of the equator as the seasons change.

September will have a trio celestial conjunction. Here's how to see the moon and Venus together in Arizona and upcoming alignments.

On Sept. 21, Earth will find itself in between Saturn and the Sun. Here's everything you need to know about this astronomical ...

Day and night will get equal time for a brief moment Monday as much of the world heads into fall. The autumnal equinox marks ...

Much as we may treasure and proclaim our independence, we actually live in a protective bubble called the heliosphere.