Astronomers have discovered a Jupiter-sized planet - 163 light-years away - that seems to think it's a comet. It has a prominent "tail" of helium gas.

Venus reached its brightest last week, just as the waning moon swept past.

Use the young moon to find Saturn after sunset on December 8 or 9, 2018. On December 9 and 10, the illuminated portion of the moon will be pointing toward Saturn.

“We were looking for a signal that would prove that this object incorporates some technology."

At least 18 of the new planets are less than 2 times larger than the Earth, and are likely to have rocky compositions with atmospheres comparable to Earth's.

Sundogs - aka parhelia - are caused by ice crystals in the air. They're most easily seen when the sun is low.

The bright planet Mars and faint planet Neptune are in conjunction now, near each other on our sky's dome. Here's a fanciful image and a more realistic one.

As far back as 40,000 years ago, cave-dwellers in what's now Turkey, Spain, France and Germany all used a method of date-keeping based on the stars. Some of their cave paintings aren't just depictions of wild animals; instead they represent constellations in the night sky.

Peering into the heart of the giant Coma cluster of galaxies, the Hubble Space Telescope captured a whopping 22,426 globular star clusters scattered among the Coma cluster's 1,000 galaxies.

We weren't sure if any of you would catch Mercury so near the sunrise glare. But you did!