Cosmology’s Great Debate began a century ago – and is still going

Harlow Shapley and Heber Curtis debated the nature of galaxies like Andromeda in 1920 Bettmann/Getty Images;…

Crash clock says satellites in orbit are three days from disaster

An artist’s representation of satellites in orbit around Earth yucelyilmaz/Shutterstock A collision would occur in just…

The stargazing events to look forward to in 2026

Watching the solar eclipse in Menan, Idaho in 2017 Natalie Behring/Getty Images As one year draws…

Saturn’s rings form a giant dusty doughnut encircling the planet

Saturn and its rings, captured by the Cassini spacecraft NASA/JPL-Caltech/Space Science Institute Specks of dust from…

Mars may once have had a much larger moon

The Gale crater on Mars ZUMA Press, Inc./Alamy A Mars crater may have once contained water…

Earth and solar system may have been shaped by nearby exploding star

SNR 0519, the remnant of a supernova that exploded about 600 years ago Claude Cornen/ESA/Hubble &…

Comets were on fire this year – for better or worse

Comet Lemmon, photographed from northern Italy on 26th October 2025 Marcel Clemens/Alamy I don’t think anyone…

Why we only recently discovered space is dark not bright

Adobe Stock Photo/Phoebe Watts A blue Earth ascends over the barren surface of the moon, against…

Odd elements in supernova blast might have implications for alien life

The supernova remnant Cassiopeia A NASA/JPL-Caltech/O. Krause (Steward Observatory) Hidden within Cassiopeia A, the youngest known…

Comet 3I/ATLAS from beyond solar system carries key molecule for life

Comet 3I/ATLAS is only the third known visitor to our solar system from elsewhere International Gemini…