A green comet,Winning Exchange cancer-sniffing ants, stealthy moons ... hang out with us as we dish on some of the coolest science stories in the news! Today, Short Wave co-hosts Emily Kwong and Aaron Scott are joined by editor Gabriel Spitzer. Together, they round up headlines in this first installment of what will be regular newsy get-togethers in your feed.

Green Comet

Emily plans to spend her Friday night stargazing, scanning the skies for a visitor that was last seen when Neanderthals and saber-toothed cats prowled the earth. Comet C/2022 E3 ZTF has been out of sight for about 50,000 years. In its triumphant return, the comet comes wrapped in a green halo – the result, Emily says, of light scattering off the diatomic carbon in the comet. "I like to think of it like it's an ancestor coming to visit," she says. "It's this chemical message in a bottle from our early solar system."

King Of The Moons

Saturn has been the gold medal holder for most known moons in our Solar System. But a recent announcement from the Minor Planet Center has shuffled the standings. The MPC identified 12 new moons orbiting Jupiter, making the big gas giant the solar system's new Moon King. Many of the newly discovered moons have retrograde orbits, meaning they revolve around Jupiter in the opposite direction of the planet's rotation. That suggests these moons weren't born there, but were captured by Jupiter's irresistible gravity.

Cancer-Sniffing Ants

Ants have exquisitely well-tuned sniffers, and now scientists are harnessing their super-smell to detect human cancers. Aaron explains how researchers in France have trained ants to distinguish between urine from a mouse with a human tumor and a cancer-free mouse. The study showed that in as few as three sessions, ants can be trained to tell the difference. Scientists are treating this as a proof of concept, rather than a practical diagnostic tool, for now. But researchers are also teaching other animals like dogs to sniff out cancer!

Have suggestions for what we should cover in our next news roundup? Email us at [email protected].

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This episode was produced by Thomas Lu and edited by Rebecca Ramirez, with help from Brent Baughman. Anil Oza checked the facts, and the audio engineer was Alex Drewenskus.