amma-ray bursts are the most powerful explosions in the Universe, briefly outshining all the stars in their galaxy combined. They typically last for just seconds or a few minutes at the most. In 2022, an ultra-long gamma-ray burst exploded in the sky, lasting so long, with two separate blasts of radiation that it triggered the Fermi Gamma-Ray Burst Monitor twice. The blast was clocked at almost 1000 seconds, with a double blast that made some astronomers wonder if it was due to a gravitational lens.

Determining the age of a star is surprisingly tricky and has wide error bars. It's only inside star clusters that you get a chance to accurately measure a star's age since they all had the exact origin and age. But a new technique hopes to discover the age of stars by measuring their rotation. As stars get older, their rotation rate slows down. By plotting the rotation rates of stars in clusters against their known ages, they can apply it to individual stars which aren't in clusters.

The time to catch Comet T4 Lemmon is now, before it vanishes for another 36,000 years.

NASA's Perseverance rover took its 20th sample from "Emerald Lake," an area filled by rocks that were deposited by an ancient river.

Unlike Earth, Venus lacks the plate tectonics that give rise to volcanoes. But the surface of Venus looks far younger than other worlds, like Mars or the Moon, which means it does have volcanic activity that regularly resurfaces the planet. Because Venus is closer to the Sun, it came farther out in the Solar System and hit the planet at higher velocities. A new study suggests that early catastrophic asteroid impacts melted its mantle, leading to its flavor of volcanism.

Astronomers have found a massive galaxy that contains little to no Dark Matter, something that doesn't fit with current cosmological models.

Here's a new one. Astronomers have found a white dwarf star - the dead remnant from a main sequence star like the Sun - with one hemisphere composed of hydrogen while the other is covered in helium. The star was discovered with the Zwicky Transient Facility, revealing that it rotates every 15 minutes. Spectroscopic data unveiled its two-sided nature. What?! Also. How?! Some white dwarfs transition from hydrogen- to helium-dominated surfaces, and astronomers might have caught it in the act.

Space telescopes use traditional polished mirrors like ground telescopes, which are heavy, unwieldy, and expensive to build. A new type of flexible telescope lens could be lighter and larger, creating space telescopes that could collect 100 times more light than JWST. Instead of a single large, delicate telescope, the Nautilus Space Observatory would consist of a fleet of lighter, cheaper, identical spacecraft working together to produce images. They'd use thin diffractive lenses, which have been improved to the point that they can produce near-perfect image quality.