Astronomy

Radio astronomers hunting for the faint whispers of the early universe face an unexpected threat from above: satellites designed to be silent are leaking radio noise into space. New research using the Murchison Widefield Array has set the first limits on unintended radio emissions from distant geostationary satellites, revealing that most remain mercifully quiet in the frequency range crucial for next-generation telescopes. The findings offer cautious hope that the Square Kilometre Array, set to become the world's most sensitive radio telescope, might avoid the radio pollution crisis now plaguing observations of low Earth orbit satellites.

It is still

Apollo 17 at Shorty Crater

Scientists have successfully transplanted gene-edited insulin-producing cells into a man with type 1 diabetes—allowing him to make some of his own insulin without immunosuppressants.

Astronomers have been observing the Cosmic Owl for years, wondering if what they were seeing was a long-predicted runaway black hole. Now, 50 years after scientists first predicted the phenomenon, the JWST has provided the clinching evidence.

An oil tanker seized by the U.S. this week reportedly used a technique that scrambled its location, but new advanced visual tracking can help expose such ships’ true coordinates

The NASA/ESA Hubble Space Telescope reobserved interstellar comet 3I/ATLAS on 30 November with its Wide Field Camera 3 instrument. At the time, the comet was about 286 million km from Earth. Hubble tracked the comet as it moved across the sky.

The FDA is reportedly considering the addition of high-level warning labels to COVID vaccines, a move that some experts say may cause unfounded concerns over safety

Efforts to lower the levels of CO2 in the atmosphere may come too late to prevent long-term changes to the Arctic

Efforts to lower the levels of CO2 in the atmosphere may come too late to prevent long-term changes to the Arctic

A new report identifies searching for life as the top science priority for humanity's first landing on Mars, ranking it above understanding water cycles, mapping geology, or even studying how the Martian environment affects astronaut health. The report outlines four possible exploration campaigns, with the highest ranked approach calling for missions totalling 330 sols at a single scientifically rich site where crews could investigate everything from ancient lava flows to active dust storms. By placing the search for extraterrestrial life at the centre of human Mars exploration, the report reimagines the first crewed mission not just as a milestone for spaceflight but as humanity's best chance to answer whether we're alone in the universe.

The Calabash Nebula, pictured here — which has the technical name OH 231.8+04.2 — is a spectacular example of the death of a low-mass star like the Sun. This image taken by the NASA/ESA Hubble Space Telescope shows the star going through a rapid transformation from a red giant to a planetary nebula, during which it blows its outer layers of gas and dust out into the surrounding space. The recently ejected material is spat out in opposite directions with immense speed — the gas shown in yellow is moving close to a million kilometres an hour. Astronomers rarely capture a star in this phase of its evolution because it occurs within the blink of an eye — in astronomical terms. Over the next thousand years the nebula is expected to evolve into a fully fledged planetary nebula. The nebula is also known as the Rotten Egg Nebula because it contains a lot of sulphur, an element that, when combined with other elements, smells like a rotten egg — but luckily, it resides over 5000 light-years away in the constellation of Puppis (The Poop deck).

There are two small moons in orbit around Mars today, but both may be remnants of a much larger moon that had enough of a gravitational pull to drive tides in the Red Planet's lost lakes and seas

There are two small moons in orbit around Mars today, but both may be remnants of a much larger moon that had enough of a gravitational pull to drive tides in the Red Planet's lost lakes and seas

Great news! We'll have dark skies for the year's richest meteor shower.

The post Geminid Meteor Shower Peaks December 13-14 appeared first on Sky & Telescope.

Week in images: 08-12 December 2025

Discover our week through the lens

Image: XMM-Newton sees comet 3I/ATLAS in X-ray light

Video: 00:22:19

Step inside astronaut training with ESA astronaut Pablo Álvarez Fernández as he shares his training journey from Cologne in Germany to Houston in the US. Discover what it’s like to wear a 145 kg spacesuit underwater, train for emergencies like fires and ammonia leaks and prepare for the ultimate astronaut dream: a spacewalk. Plus, Pablo talks about life in Houston, teamwork under pressure and what’s next on his path to the stars. 

This interview was recorded in December 2024. 

You can listen to this episode on all major podcast platforms. 

Keep exploring with ESA Explores!

Let’s say you are transported back in time to some ancient culture. And along the way you somehow forget everything you knew about modern cosmology (don’t worry about the details, it’s just to get us going here, pretend if you have to that it’s a very strange and selective sort of amnesia introduced by the time traveling device).