Thursday, July 23, 2026

Chandrasekhar and the Limits of Physics, Part 4: Vindication

The remnant of Tycho's supernova, a Type Ia explosion, in X-ray light. Such blasts happen when a white dwarf reaches the Chandrasekhar limit. Credit: NASA / Wikimedia Commons (public domain).

The collapsing stars Eddington swore couldn't exist turned out to be everywhere, and half a century later the world handed Chandrasekhar his Nobel. How the 1.4 solar mass limit became one of the most important numbers in modern astronomy.



Probing the Universe's Missing Matter With Mysterious Fast Radio Bursts

This illustration shows a Fast Radio Burst form a distant galaxy reaching Earth. In new work, researchers used thousands of FRBs to probe the Universe for its missing matter. Image Credit: ESO/M. Kornmesser

Astronomers aren't certain where Fast Radio Bursts come from. But they still have utility. They can use them to find the Universe's "missing matter."



Wednesday, July 22, 2026

The Milky Way Flipped its Disk Billions of Years Ago

The Milky Way in the sky over the ESO's La Silla Observatory in Chile's Atacama Desert. The Milky Way's thick disk is full of older stars and rotates more slowly than its thin disk, which is full of younger stars. New research says a cosmic flip is responsible for this puzzling arrangement. Image Credit: ESO/B. Tafreshi (twanight.org)

The Milky Way has two disks, the thin disk where most of the stars dwell, and the thick disk, populated by much older stars. The ESA's Gaia mission showed us that the thick disk rotates more slowly than the thin disk. The culprit, according to powerful simulations, was a disk flip in the MW's past, driven by a merger.



Tuesday, July 21, 2026

Electrically Charged Mars Storms Threaten Future Exploration

Orbital image of the global dust storm occurring in Martian Year 34 (mid-2018), which enveloped the entire Red Planet. (Credit: NASA/ESU)

Martian dust storms are some of the most fascinating and mysterious planetary surface processes ever observed, as Earth, Mars, and Saturn’s moon Titan are the only known planetary bodies to have active dust storms. However, the major difference for Mars is its dust storms can blanket the entire planet at once, resulting in the surface becoming completely unobservable and blocking out sunlight, with the scientific community concerned this might hinder robotic, and even human, space exploration. But what if covering the surface and blocking sunlight wasn’t the only issue Martian global dust storms pose for future missions?



NASA's Psyche Spacecraft Captured a Time-Lapse Video of its Mars Flyby

In May, NASA's Psyche spacecraft performed a gravity-assist maneuver that sent in on its way to its target, the metal-rich asteroid 16 Psyche. The flyby was also an opportunity to test the spacecraft's instruments, including its multispectral camera. NASA has released a time-lapse video of the encounter. Image Credit: NASA/JPL

NASA's Psyche mission used a gravity assist maneuver at Mars to gain velocity and adjust its trajectory to its eventual target. The asteroid 16 Psyche is a metal-rich asteroid that may be the remnant rocky core of a protoplanet. The flyby not only shepherded the spacecraft on to its target, it was also an opportunity to test Psyche's science instruments and cameras. NASA has released a timelapse of the flyby.



Astronomers Are Still Trying to Understand How a Galaxy's Spiral Arms Form

The Whirlpool Galaxy (M51) is the classic grand design spiral galaxy. It was the first object recognized as a spiral, though at the time astronomers thought they were nebulae. Astronomers have been pondering spiral galaxies for a long time, trying to understand how their spiral arms persist. New research has at least a partial answer. Image Credit: NASA, ESA, S. Beckwith (STScI) and the Hubble Heritage Team (STScI/AURA)

Spiral galaxies, including grand spirals like the Whirlpool galaxy, are plentiful. But it's still a mystery how their spiral arms form and persist for hundreds of millions of years, and why some galaxies have one, two, or three or more arms. New research based on Euclid data finds links between galaxy mass, star formation rate, and number of arms, and hints at their formation.



Astronomers Catch a "Dark Comet" Red-Handed

Artist's depiction of a near-Earth asteroid with an elongated orbit. Credit - NASA/JPL-Caltech

Our ability to track and visualize small rocks in space is still improving. And occasionally we’ll find a space rock that will remind us of that fact. One such rock is detailed in a new paper, led by Davide Farnocchia of NASA’s Jet Propulsion Laboratory, and recently published in Nature Astronomy, where the research team discovered what they thought was a normal, run of the mill asteroid, was actually a “dark comet”.