Meteorologists issue warnings, watches and advisories as extreme heat grips Pacific Northwest this weekend, into next week. Triple-digit highs expected.

Krill in the Southern Ocean are projected to decline about 30% this century, due to human-driven climate change. But natural variability also plays a role. A new study tries to tease out the difference.

A popular adage among mushroom foragers is, “you can eat any mushroom ... once.” Some wild mushrooms are poisonous and will make you sick. A few can kill.

Researchers used the Large Hadron Collider to investigate the 1st matter formed in the 1st microsecond of Big Bang. They said it had liquid-like properties.

A new experiment aboard the ISS is studying tardigrades - aka water bears - to better understand how they tolerate extreme environments, including the one astronauts experience in space.

NASA Administrator Bill Nelson wants the space agency to start taking a closer look at UFO reports like the ones coming from Navy pilots in recent years. He has directed NASA scientists to move forward with new ways of discussing the decades-old phenomenon.

Space officials called it a "lucky strike" when space debris smacked into the skinny robotic arm on the space station, creating a hole now seen in images.

The US Pentagon UFO report - an unclassified document - is due in June 2021. It's supposed to reveal everything government agencies know about UFOs.

Enjoy a few photos of the May 21, 2021 lunar eclipse from EarthSky friends around the world. Thanks so much to all who shared your photos with us!

The complex interplay among many factors - African monsoons, ocean temperatures, wind shear, El Niño and La Niña – that go into predicting hurricane season.