Here’s an introduction to Comet C/2023 A3—the latest bright comet to grace our skies in the inner solar system.

Header Image: Comet C/2022 E3 (ZTF) showing its green glow and three blue ion tails. Image Credit: Jose Francisco Hernández Everyone is talking about the “Green Comet”—aka Comet C/2022 E3 (ZTF)—right now! This cosmic fuzzball recently made its closest approach to the Sun, and has the potential to be bright enough to be seen from […]

Header Image: Comet C/2022 E3 (ZTF) showing its green glow and three blue ion tails. Image Credit: Jose Francisco Hernández Editor’s Note: Updated to include information about hyperbolic orbits. Comet C/2022 E3 (ZTF), informally called the “Green Comet”, recently made its closest approach to the Sun, after having traveled tens of thousands of years from […]

Header Image: The outside of the Adler Planetarium at night with the Moon, Jupiter, and Saturn brightly lit in the background. Image Credit: Mike Smail If skies are clear, we’ll get a chance to see all the planets visible to the unaided eye—and, just maybe, a comet—this month, December 2021. Comet Leonard, discovered in January […]

Image Caption: The Andromeda Galaxy taken by an astrophotographer. Image Credit: Nick Lake From galactic paintings to space poetry, everyone’s favorite out-of-this-world muse—aka our universe—inspires all kinds of stellar works of art. Our staff came together and composed a few short poems all about aspects of space that inspire them. STAGES In my youth, I […]

What’s better than the near approach of a comet? How about the near approach of two comets? That’s what we’re expecting during the month of May, 2020! Comet C/2019 Y4, also known as Comet ATLAS, was discovered late last December. It will come closest to Earth on May 23rd, at a distance of about 72 […]

Header Image: While C/2019 Q4 (Borisov) is too far away for us to get detailed images, it probably looks something like this image taken on March 27, 2016, by the Rosetta spacecraft, 329 km from the nucleus of Comet 67P/Churyumov-Gerasimenko. The image measures 28.7 km across. Image Credit: ESA/Rosetta/NavCam The Day the Adler Met an […]

Have you ever seen a comet in the night sky? I suspect most of the people reading this haven’t. It’s not that there aren’t a lot of comets in the Solar System—more than 5,000 have been discovered so far and several dozen can be spotted using very large telescopes each year—but because most comets are […]