Astronomy

The search for dark matter requires all of the best models, theories, and ideas we can throw at it. A new paper from Julia Monika Koulen, Stefano Profumo, and Nolan Smyth from the University of California at Santa Cruz (UCSC) tackles the implications of the sizes and abundance of one of the more interesting dark matter candidates - primordial black holes (PBHs).

Proxima Centauri b is the closest known exoplanet that could be in the habitable zone of its star. Therefore, it has garnered a lot of attention, including several missions designed to visit it and send back information. Unfortunately, due to technological constraints and the gigantic distances involved, most of those missions only weigh a few grams and require massive solar scales or pushing lasers to get anywhere near their target. But why let modern technological levels limit your imagination when there are so many other options, if still theoretical, options to send a larger mission to our nearest potentially habitable neighbor? That was the thought behind the Master’s Thesis of Amelie Lutz at Virginia Tech - she looked at the possibility of using fusion propulsion systems to send a few hundred kilogram probe to the system, and potentially even orbit it.

What new methods can be developed in the search for extraterrestrial intelligence (SETI)? This is what a recent white paper submitted to the 2025 NASA Decadal Astrobiology Research and Exploration Strategy (DARES) Request for Information (RFI) hopes to address as a pair of researchers from the Breakthrough Listen project and Michigan State University discussed how high-energy astronomy could be used for identifying radio signals from an extraterrestrial technological civilization, also called technosignatures. This study has the potential to help SETI and other organizations develop novel techniques for finding intelligent life beyond Earth.

One of the most iconic cosmic scenes in the Universe lies nearly 3.8 billion light-years away from us in the direction of the constellation Carina. This is where two massive clusters of galaxies have collided. The resulting combined galaxies and other material is now called the Bullet Cluster, after one of the two members that interacted over several billion years. It's one of the hottest-known galaxy clusters, thanks to clouds of gas that were heated by shockwaves during the event. Astronomers have observed this scene with several different telescopes in multiple wavelengths of light, including X-ray and infrared. Those observations and others show that the dark matter makes up the majority of the cluster's mass. Its gravitational effect distorts light from more distant objects and makes it an ideal gravitational lens.

Earlier this year, asteroid 2024 YR4 was discovered and found to have a trajectory through the Earth/Moon system in 2032. The world's telescopes focused on the potential threat and downgraded the chance to negligible for the Earth...but it still has a non-zero chance of hitting the Moon. As the asteroid became too dim to continue observing, its Moon impact chance stood at 4%. When will we update this number? Not until it does another close flyby in 2028.

This illustration shows the parts of a space shuttle orbiter. About the same size and weight as a DC-9 aircraft, the orbiter contains the pressurized crew compartment (which can normally carry up to seven crew members), the cargo bay, and the three main engines mounted on its aft end.

Kat Zhou has won the Aquatic Life category in the 2025 BigPicture Natural World Photography Competition, while a shot of a death-defying leap by a lemur took the top prize

Kat Zhou has won the Aquatic Life category in the 2025 BigPicture Natural World Photography Competition, while a shot of a death-defying leap by a lemur took the top prize

Isometric exercises like wall squats are gentle on your body, but can enhance your fitness in a surprisingly efficient way, discovers Grace Wade 

Isometric exercises like wall squats are gentle on your body, but can enhance your fitness in a surprisingly efficient way, discovers Grace Wade 

Foundation's new series is full of new characters and dramatic potential. But instead of mining those rich seams, too many plotlines have become shallow and absurd. It's hard to see a good show go bad, says Bethan Ackerley

Foundation's new series is full of new characters and dramatic potential. But instead of mining those rich seams, too many plotlines have become shallow and absurd. It's hard to see a good show go bad, says Bethan Ackerley

Language is evolving rapidly in a world of social media. Our millennial reviewer finds Adam Aleksic's Algospeak to be a much-needed helping hand

Language is evolving rapidly in a world of social media. Our millennial reviewer finds Adam Aleksic's Algospeak to be a much-needed helping hand

The awe-inspiring distances of the cosmos are hard to visualise, so how can we be certain we are measuring them correctly? Chanda Prescod-Weinstein explains

Feedback has been invited to an event next year in Shaoxing, China. It's an academic conference promising "revolutionary thinkers who are redefining human intimacy through cutting-edge robotics and AI"

The UK's health secretary has announced a 10-year plan to check newborns for a huge range of rare conditions. There are major medical and ethical issues with this, argues neurologist Suzanne O'Sullivan

The population is set to plummet and we don't know how to stop it, warn Dean Spears and Michael Geruso in their new book, After the Spike