SUNSET: 
Triple Supernova Image Stokes Hubble Constant Controversy
A unique supernova image provides astronomers with an alternative way to measure the universe’s current expansion, hinting that it’s (still) faster than expected.
Solar Probe Duo Unravel Solar Wind Mystery
For decades, scientists have wondered what accelerates solar wind particles as they move away from the Sun. New evidence points to magnetic switchbacks.
High School Citizen Scientists Join the Hunt for Exoplanets
A group of high school astronomy students helped confirm and characterize a planet slightly smaller than Saturn that closely orbits its star.
Webb Telescope Finds Strangely Bright Galaxies at Cosmic Dawn
Another record-breaker: Two galaxies date to only 300 million years after the Big Bang. How did they grow so big and bright so quickly?
Webb Telescope Finds Most Distant Black Hole Merger
A new JWST study has found evidence of two galaxies colliding 740 million years after the Big Bang.
April Fool’s on the arXiv, 2024 edition
On this April 1st, astronomers reveal fascinating discoveries inspired by astrology, pasta, Star Wars, and flamingos.
Webb Telescope Measures Universe’s Expansion
Astronomers have used the Webb telescope to observe Cepheid variable stars, ruling out one source of the prevailing "Hubble tension.”
Largest-ever Catalog of X-ray Sources Tests Cosmology
Results from a brand-new high-energy observatory are rocking the field of cosmology. In particular, a study of more than 5,000 galaxy clusters relieves tension in the standard cosmological model.
How Strong Is Dark Energy? Intriguing Findings from New Supernova Catalog
The largest sample of Type Ia supernovae ever made by a single telescope sheds light on dark energy.
Atomic Oxygen Detected on Venus
New data provide direct evidence for the existence of atomic oxygen in Venus's upper atmosphere, enabling new science on our sister planet.
How Did Two Hot and Super-dense Neptunes Form?
Astronomers have discovered two Neptune-size planets that are denser than rock and in searingly close orbits to their star. How did these odd worlds form?
Another Early-Universe Mystery: JWST Spies Dust at Cosmic Dawn
Dust is usually the product of generations of star formation. So what is all this dust doing in the early universe, just a few hundred million years after the Big Bang?
Webb Telescope Tracks Universe's First Light
New results from the James Webb Space Telescope find that radiation from ordinary galaxies cleared the primordial haze left over from the Big Bang, allowing the first light to shine through the early universe.
Does This Star Cluster Host a Black Hole in Its Core?
The well-known star cluster Messier 4 might have an elusive, midsize black hole hidden at its center, but the evidence isn’t conclusive yet.
The James Webb Space Telescope May Have Spotted a Baby Galaxy Merger
New JWST images reveal that one of the most distant objects ever observed is actually two baby galaxies on a possible collision course.
The Moon Deimos Might Be a Piece of Mars
Surprising new results from the United Arab Emirates' Hope probe call the origin of Mars's smaller moon into question.
Giant Planets Around Small Stars
Leading theories say giant planets shouldn’t be able to form around very low-mass stars. But a new study finds that, nevertheless, they do.
New Planets in the Neighborhood
A planet-hunting consortium is marking five successful years by releasing data on more than 50 worlds.
Webb Telescope Surveys a Hot Saturn
A collection of five research studies delve into the atmosphere of exoplanet WASP-39b as astronomers seek to better understand the chemistry of a world beyond the solar system.
Tentative Evidence of the First Generation of Stars
Scientists have detected something unusual around a distant quasar — perhaps the first real evidence of a first-generation star.
