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How fast is our universe expanding?

Here’s a great New ScienceCast video about the controversial Hubble Constant. It’s the key to knowing the age of our universe and much more.

Zap! Biologist measures electric eel’s shock on his own arm

Talk about dedication to science! This biologist stuck his arm into an eel tank – 10 times – to get an accurate measure of an eel’s shock. He said it felt “like touching a horse fence.”

Aging star blows off smoky bubble

A strikingly beautiful view of a delicate bubble of expelled material around the exotic red star U Antliae helps astronomers understand how stars evolve during the later stages of their life-cycles.

More Cassini legacy: Titan’s bonkers atmosphere

Cassini’s legacy will endure. Click for a video about the atmosphere of Saturn’s large moon Titan, which might resemble that of an early Earth.

Another X-flare from the sun

We’re near solar minimum, but the sun has been active! Click here for a video of solar flares so far in September, 2017 and for news for the sun’s most recent X-flare.

X-ray astronomy and planet-hosting stars

X-ray astronomers explored how quickly young stars settle down after blasting the space around themselves – including any possible planets – with energetic radiation.

Asteroid 3122 Florence: Video and images

This large asteroid swept closest to Earth on September 1. It’s big enough that astronomers are still catching it in small telescopes, as a small, slow-moving “star.”

Mystery of high-energy cosmic rays

Hold out your hand for 10 seconds. A dozen electrons and muons just zipped through your palm. These cosmic rays, scientists believe, come from violent explosions in deep space.

Space station transits sun during eclipse

There was only one part of Earth where you could catch the International Space Station crossing the sun’s face during the August 21 solar eclipse. These guys saw it, and created this video.

The hunt for asteroids

New short video from NASA about the hunt for potentially hazardous asteroids and comets, and ways to defend Earth against them.