Tag: cosmic

Curious asteroid Selam, spotted by NASA’s Lucy spacecraft, is a cosmic toddler

When NASA’s Lucy mission passed by the near-Earth asteroid Dinkinesh last November, it discovered that Dinkinesh had a companion — a little moonlet that astronomers soon named Selam. And now, scientists have measured Selam’s age. Their estimate suggests that tiny Selam separated from its larger partner Dinkinesh just 2 to 3 million years ago, making […]

Earth got hammered by cosmic rays 41,000 years ago due to a weak magnetic field

Earth is under constant bombardment by high-energy charged particles called cosmic rays. We’re normally shielded from this barrage by Earth’s magnetic bubble, the magnetosphere. But what happens when this shield weakens? Cosmic rays are primarily hydrogen nuclei blasted into space by powerful celestial events such as the supernova deaths of massive stars. These incredibly energetic […]

The mystery of how strange cosmic objects called ‘JuMBOs’ went rogue

At the end of 2023, astronomers made a startling discovery in the Orion Nebula. Using the James Webb Space Telescope (JWST), the team found 40 pairs of planetary mass objects — none of which orbit a star. They’re called Jupiter-Mass Binary Objects, or JuMBOs. In short, this discovery directly challenged both star birth and planet […]

Tim Pennings: Cosmic distances

Did you experience the recent solar eclipse? Have you ever considered how special such an event is? Not because it happens only every few years, but because it happens at all. The moon and sun are just the right sizes and just the right distances from Earth that the apparent size of the moon is […]