Category Astronomy/Space

You might have seen an interesting phrase popping up in your social media feeds lately: “Chiron is in retrograde.” If you’re anything like me, you’ve never heard of Chiron before—and I’m a professional astronomer.

So what is Chiron, and what does it mean to be in retrograde? The short answer is that Chiron is an asteroid-slash-comet orbiting somewhere past Jupiter and Saturn. And until January 2026, it’s going to look like it’s going backwards in the sky. If you can spot it.

But there’s a bit more to the story.

What is Chiron?
Chiron’s official name is (2060) Chiron. First things first: it’s pronounced “kai-ruhn,” with a hard K sound.

It was discovered by astronomer Charles Kowal in 1977...

Astronomers have discovered potentially the most massive black hole ever detected. The cosmic behemoth is close to the theoretical upper limit of what is possible in the universe and is 10,000 times heavier than the black hole at the center of our own Milky Way galaxy.

It exists in one of the most massive galaxies ever observed—the Cosmic Horseshoe—which is so big it distorts spacetime and warps the passing light of a background galaxy into a giant horseshoe-shaped Einstein ring.

Such is the enormousness of the ultram...

The imaging team of NASA’s Perseverance Mars rover has taken advantage of clear skies on the red planet to capture one of the sharpest panoramas of its mission so far. Visible in the mosaic, which was stitched together from 96 images taken at a location the science team calls “Falbreen,” are a rock that appears to lie on top of a sand ripple, a boundary line between two geologic units, and hills as distant as 40 miles (65 kilometers) away...

A recent study led by Dilda Berdikhan, a Ph.D. student from the Xinjiang Astronomical Observatory (XAO) of the Chinese Academy of Sciences, has uncovered compelling evidence that a cloud–cloud collision has triggered active star formation in the molecular cloud G013.313+0.193 (hereafter G013.313) in the Milky Way. The findings are published in Astronomy & Astrophysics.

Using observational data from the NanShan 26-m Radio Telescope and the Delingha 13...