![An expanding cloud of debris from a supernova](jpg/snr0519c72e.jpg)
Surprising Supernova Scars Cover the Earth
A supernova showering Earth with radioactive debris is a surprisingly common cosmic occurrence
Phil Plait is a professional astronomer and science communicator in Virginia. He writes the Bad Astronomy Newsletter. Follow him online.
Surprising Supernova Scars Cover the Earth
A supernova showering Earth with radioactive debris is a surprisingly common cosmic occurrence
How Can You ‘See’ a Black Hole?
How do astronomers find the darkest objects in the universe?
Don’t Panic—At Least, Not about a Nearby Supernova
An exploding star is a catastrophe on a cosmic scale, but here on Earth we’re safe from such astral disasters—for now
Where Is the Edge of the Solar System?
The solar system’s outer limits aren’t as clear-cut as you might think
The Threat of a Solar Superstorm Is Growing—And We’re Not Ready
Someday an unlucky outburst from our sun could strike Earth and fry most of our electronics—and we’ve already had some too-close-for-comfort near misses
How to See the Lunar Far Side Right Here on Earth
Perspective and subtle motion allows us to peek over the moon’s edge and into its far side
How Tides Move Heaven and Earth
The ocean’s twice-daily rise and fall is only the most obvious effect of tides—they slow Earth’s spin and shape stars and galaxies, too
A Solar Eclipse Is Too Special to See Through Your Smartphone
To make the most of any total solar eclipse, put down your gadgets and bask in one of our solar system’s most glorious spectacles
Do Stars Outnumber the Sands of Earth’s Beaches?
Figuring out whether there are more stars in the universe than sand grains on Earth’s seashores requires math—and imagination
Earth Has More Than One Moon
Quirks of orbital mechanics make a cadre of sun-orbiting asteroids appear to be moons of Earth
Astronomers Are Snapping Baby Pictures of Planets by the Dozen
Snapshots of a plethora of planet-forming disks offer more than just eye candy—they also reveal some fundamental aspects of how worlds are born
NASA’s Hopes for Space Solar Power Are Looking Dim
Exorbitant launch costs and daunting engineering challenges make the dream of space-
based solar power look dicey for the space agency
The Scale of Space Will Break Your Brain
The scale of the cosmos exceeds the bounds of human comprehension. But that doesn’t mean the universe is beyond our understanding
Speeding Stars Can Reveal the Milky Way’s Fate
Maps of stellar motions can show whether the Milky Way will someday merge with the Andromeda galaxy—and a whole lot more
Why Do We Have a Leap Year Anyway?
Without adding an extra day to February every four years, our calendar would get increasingly out of sync with the cosmos
Under Pluto’s Sunny Skies, You’d Have to Wear Shades
Despite being some six billion kilometers away, the sun from Pluto would be a dazzling sight to behold—carefully, that is
Planets Orbiting Dead Stars Foretell the Solar System’s Far-Future Fate
Images of possible planets around white dwarf stars suggest that some gas-giant worlds survive the deaths of their stellar host
When We Find Earth 2.0, What’s Next?
We’re looking for another Earth. But how likely is it that we’ll find a duplicate of home?
Where Does Outer Space Begin?
The popular limit of a 100-kilometer altitude for the edge of space should probably be adjusted down to 80 km
How Far Away Is the Horizon?
The edge of the world is closer than you think, and simple geometry proves it
This Nearby Brown Dwarf May Have Auroras—And a Moon, Too
Glowing methane on a brown dwarf dozens of light-years from Earth may signal the presence of a large lunar companion
Earth’s Wobble Wreaks Havoc on Astronomers—And Astrologers, Too
Our planet’s precession is scarcely noticeable during anyone’s lifetime, but across history, it has had enormous effects
Sky Spectacles to Watch in 2024
Here’s a calendar of cosmic events to keep your eyes on in the coming year
Behold—the Best Space Images of 2023
This year’s most interesting space images include infrared views of galactic “bones,” an asteroid’s double moon, Jupiter’s giant polar vortex, and more