Ending 2025 with a bang

Space Snapshot

The future starts with people like you. Are you in?

You’re part of the world’s largest, most respected, and most effective citizen space organization. With all that’s at stake for space science and discovery in the year ahead, we’re counting on you so we can show up where it matters most, when it matters most to save NASA science, work hard to advance our goals, and fund innovative programs like our STEP and Shoemaker NEO grants. Please donate today to help build our future in space!

Pictured: This James Webb Space Telescope (JWST) image shows the Westerlund 2 star cluster, 20,000 light-years away from Earth. This particular region is home to some of the hottest, brightest, and most massive stars known. Image credit: ESA/NASA/CSA, et al.

Fact Worth Sharing

JWST’s extraordinary power and sensitivity allow it to detect things that other telescopes cannot. In the Westerlund 2 star cluster, for example, it observed previously-unseen brown dwarfs as small as about 10 times the mass of Jupiter.

From The Planetary Society

Speaking of brown dwarfs… The boundaries of planethood can sometimes be blurry. For example, a free-floating object several times the mass of Jupiter might be considered a rogue planet (a planet that isn’t gravitationally bound to a star) or a brown dwarf (a “failed star” that isn’t massive enough to fuse helium). Learn more in our guide to rogue planets — what they are, how they form, and how they challenge categorization. Pictured: An artist’s impression of a rogue planet. Image credit: NASA/JPL-Caltech.

A world’s a world, no matter how small. That’s Kate Howells’ view when it comes to moons. Even tiny planetary satellites are fascinating worlds unto themselves, as she explores in her book “Moons: The Mysteries and Marvels of our Solar System.” The author (who also serves as The Planetary Society’s public education specialist) discusses moons big and small in her interview in The Planetary Society’s book club, featured in this month’s Planetary Radio: Book Club Edition.

It’s been a huge year for space policy and advocacy. In this week’s Planetary Radio, The Planetary Society’s space policy team unpacks what happened, why funding uncertainty matters, and what comes next for space science. You can also watch last week’s virtual Q&A with the team about what’s happened since our October Day of Action and what to expect in the coming months.

Our team is taking some time off for the holidays. That’s why there are no Mission Briefings in this week’s Downlink. We’ll skip those next week, too, but will still bring you other great space content to kick off 2026. Happy Holidays!

What's Up

In the early evening, look for yellowish Saturn high up in the west, coming somewhat close to the first quarter Moon on Dec. 26. Very bright Jupiter rises in the mid-evening.

Help save space missions. Join today!

If you are not already a member, we need your help. NASA is at a crossroads, and your support is needed today! Funding for space science and exploration is at risk. It needs the support of passionate advocates like you.

NASA is facing major budget cuts for the first time in a decade, and thousands of skilled scientists, engineers, and technicians have already been laid off at NASA centers across the United States. NASA funding must grow, not shrink, if the agency is to succeed in returning to the Moon, exploring the Solar System, and seeking out life beyond Earth.

We must prevent budget cuts. When you become a member of The Planetary Society, you join the world’s largest and most influential space advocacy nonprofit. Will you join us and enable the future of space exploration?

Wow of the Week

If you love New Year’s Eve fireworks, this one’s for you. This spectacular image shows the aftermath of a supernova explosion. The myriad colors come from X-ray, visible, and infrared data collected by the Chandra, Hubble, Webb, and Spitzer space telescopes. Image credit: NASA et al.

Send us your artwork!

We love to feature space artwork in the Downlink. If you create any kind of space-related art, we invite you to send it to us by replying to any Downlink email or writing to [email protected]. Please let us know in your email if you’re a Planetary Society member!