Category Archives: Astronomy

Our galaxy’s stars keep a record of its past

Rebecca Boyle writes: Late in the evening of October 5, 1923, Edwin Hubble sat at the eyepiece of the Hooker telescope at the Mount Wilson Observatory, atop the mountains overlooking the Los Angeles basin. He was observing an object in the northern sky. To the unaided eye, it was visible as a faint smudge. But… Read More »

Back to New Jersey, where the universe began

Dennis Overbye writes: On a field just below the summit of Crawford Hill, the highest point in Monmouth County, N.J., almost within sight of the skyscrapers of Manhattan, sits a cluster of shacks and sheds. Next to them is the Holmdel Horn Antenna, a radio telescope somewhat resembling the scoop of a giant steam shovel:… Read More »

Will the universe ever stop expanding?

Sarah Scoles writes: From Earth, the night sky looks fairly static. Sure, the stars rotate from evening to evening, and the planets move among them. But from a terrestrial perspective, the celestial sphere appears essentially unchanging. Perception, though, is not reality: our eyeballs don’t hint that beyond nearby planets, stars and galaxies, everything is moving… Read More »

Is there a crisis in cosmology?

Adam Frank and Marcelo Gleiser write: Not long after the James Webb Space Telescope began beaming back from outer space its stunning images of planets and nebulae last year, astronomers, though dazzled, had to admit that something was amiss. Eight months later, based in part on what the telescope has revealed, it’s beginning to look… Read More »

JWST spots giant black holes all over the early universe

Charlie Wood writes: Years before she was even sure the James Webb Space Telescope would successfully launch, Christina Eilers started planning a conference for astronomers specializing in the early universe. She knew that if — preferably, when — JWST started making observations, she and her colleagues would have a lot to talk about. Like a… Read More »

James Webb Space Telescope prompts a rethink of how galaxies form

Adam Mann writes: Katherine Whitaker was on a video call with colleagues last summer when NASA released the first pictures from the ultra-powerful James Webb Space Telescope (JWST). Among the many awe-inspiring images was one of a sliver of sky surrounding the galaxy cluster SMACS 0723: It was brimming with some of the oldest and… Read More »

A year of cosmic wonder with the James Webb Space Telescope

The New York Times reports: By now, perhaps, we should be getting used to unreal images of the cosmos made with the James Webb Space Telescope. But a year after NASA released the cosmic observatory’s first imagery, the space agency has dropped yet another breathtaking snapshot of our universe. Wednesday’s image was Rho Ophiuchi, the… Read More »

Neutrinos build a ghostly map of the Milky Way

The New York Times reports: From ghostlike particles, astrophysicists have pieced together a new map of the galaxy we live in. For now, that map of the Milky Way is blurry and incomplete. But as more data is gathered, it will become clearer and will help illuminate galactic convulsions like the expanding remnants of exploded… Read More »

Scientists thrill at first hints of cosmic ‘hum’ from giant gravitational waves

Scientific American reports: After nearly two decades of listening, astronomers are finally starting to “hear” the rumbles of gravitational waves they believe emanate from the behemoths of our universe: supermassive black holes. The result comes from a National Science Foundation–sponsored initiative known as the North American Nanohertz Observatory for Gravitational Waves (NANOGrav). Since 2004 NANOGrav… Read More »

Where Earth got its water

Sean Raymond writes: When Carl Sagan famously called Earth the “pale blue dot,” he was judging a book by its cover. Even though three quarters of our planet’s surface is covered by oceans, our planet is actually very dry. Water makes up about one part in a thousand of Earth’s mass (most of it is… Read More »