Soon after it was spotted in December 2024, worldwide telescopic observations quickly positioned it as the most dangerous space rock ever discovered—one that stood a 3.1-percent (or 1-in-32) chance of crashing into Earth on December 22, 2032. If it were to hit one of the cities potentially in its path, this 60-meter asteroid would have unleashed a force comparable to several atomic bombs, devastating the unfortunate metropolis.
How the most massive objects in the universe first formed is one of the biggest headscratchers in astrophysics. With more advanced telescopes, astronomers have found fully formed galaxies and colossal black holes earlier and earlier in the cosmos, just a few hundred million years after the Big Bang. This shouldn't be enough time for these structures to reach their incredible size; to astronomers, it's like stumbling on a fully-grown oak tree that's only a year old.
When the James Webb Space Telescope sent its first high-definition infrared images back to Earth, astronomers noticed several tiny, glowing, crimson stains. These objects, quickly named "Little Red Dots," were too bright to be normal galaxies, and too red to be simple star clusters. They appeared to house supermassive black holes that were far more massive than they had any right to be.
This particular exoplanet quickly captured astronomers' attention with its extreme variations in brightness. Most objects in space appear to blink, due either to physical changes within the planet or star, or external factors. For super-Jupiter exoplanets, Zhang said, this change in brightness is usually minimal, hovering at 1 to 2%. But on VHS 1256b, brightness variations neared 40%, the largest ever recorded for an object of its size.
Getting your Trinity Audio player ready... Today is Thursday, Dec. 25, the 359th day of 2025. There are six days left in the year. This is Christmas Day. Today in history: On Dec. 25, 2009, passengers aboard Northwest Airlines Flight 253 foiled an attempt to blow up the plane as it was landing in Detroit by seizing Umar Farouk Abdulmutallab (OO'-mahr fah-ROOK' ahb-DOOL'-moo-TAH'-lahb), who tried to set off explosives in his underwear. (Abdulmutallab later pleaded guilty and was sentenced to life in prison.)
Day 20 of the 2025 Space Telescope Advent Calendar: The Cosmic Cliffs. The James Webb Space Telescope peered inside a region at the edge of a gigantic gaseous cavity within the star cluster NGC 3324. The cluster, about 9,100 light-years away, near the Carina Nebula, is believed to be fairly young, only about 12 million years old.
ESA / Webb, NASA & CSA, G. Mahler Day 7 of the 2025 Space Telescope Advent Calendar: A Warped View Through an Einstein Ring. You are seeing two galaxies here, one in front of the other. The more distant spiral galaxy appears warped and distorted due to the gravitational lensing occurring around a massive, much closer galaxy, which is part of galaxy cluster SMACSJ0028.2-7537.
Day 4 of the 2025 Space Telescope Advent Calendar: Star Birth in the Lobster Nebula. NASA's James Webb Space Telescope recently imaged a region where the radiation and winds from a group of superhot infant stars are blasting and sculpting dense clouds of surrounding dust.
For the first time, scientists have directly detected molecules in a Frisbee of gas and dust swirling around an alien gas-giant planet. I didn't think this was possible, says astronomer Sierra Grant of Carnegie Science in Washington, D.C. Typically such a faint signal would be invisible in the glare of a star. Grant and her co-author Gabriele Cugno of the University of Zurich, who published the results recently in the Astrophysical Journal Letters, think the carbon-rich disk is a lunar nursery.
Astronomers say NASA's James Webb Space Telescope may have spotted the universe's first "dark stars," primordial bodies of hydrogen and helium that bear almost no resemblance to the nuclear fusion-powered stars we've come to know.
Astronomers were astonished to find an abundance of phosphine, a molecule produced by microbes on Earth, in the atmosphere of a brown dwarf, an unusual type of object that lives in the grey zone between a giant planet and a tiny star. As detailed in a new paper published in the journal Science, astronomers said they had found "undepleted phosphine," a molecule made up of three hydrogen atoms and one phosphorus atom, in the atmosphere of Wolf 1130C, a brown dwarf 54 light-years from Earth.
At the moment, there's no bet­ter way to see any­thing in space than through the lens of the James Webb Space Tele­scope. Pre­vi­ous­ly fea­tured here on Open Cul­ture, that ten-bil­lion-dol­lar suc­ces­sor to the Hub­ble Space Tele­scope can see unprece­dent­ed­ly far out into space, which, in effect, means it can see unprece­dent­ed­ly far back in time: some 13.5 bil­lion years, in fact, to the state of the ear­ly uni­verse.
To back up his far-fetched theory, Loeb has pointed out that 3I/ATLAS' highly unusual trajectory brings it suspiciously close to Jupiter, Mars, and Venus. In a new blog post, the astronomer pointed out that the object will come within just 1.67 million miles of Mars' path around the Sun, in what he characterized as a "remarkable fine-tuning" of the object's path.
