
Hypervelocity Stars Hint at a Supermassive Black Hole Right Next Door
Some stars streaking through the Milky Way at millions of kilometers per hour probably trace back to a supermassive black hole in a neighboring galaxy
Phil Plait is a professional astronomer and science communicator in Virginia. His column for Scientific American, The Universe, covers all things space. He writes the Bad Astronomy Newsletter. Follow him online.

Hypervelocity Stars Hint at a Supermassive Black Hole Right Next Door
Some stars streaking through the Milky Way at millions of kilometers per hour probably trace back to a supermassive black hole in a neighboring galaxy

What Makes Stars Twinkle?
The quirks of light moving through gas are the cause of stellar twinkling, which can be a bane—and sometimes a boon—for astronomers

What Is a Galaxy?
Galaxies come in many shapes and sizes, and trying to define them is difficult

Could the Sun Fry Earth with a Superflare?
Stars like the sun might erupt with extreme explosions about once per century

Can There Be Sound in Space?
It seems contrary to common knowledge, but sound can travel through some parts of space quite well

Strange Circles in the Sky Are Still Baffling Astronomers
ORCs—odd radio circles—are one of the weirdest recent discoveries in the heavens above

What Defines a Star?
At the lower end, and to the bitter end, defining a star is tougher than you might expect

How Many Rogue Planets Roam the Milky Way?
According to new simulations, many, even most, planets get ejected from their star early in their history

When Was the First Exoplanet Discovered?
Evidence of alien worlds goes back farther than you think

What Makes a Moon?
Defining the word “moon” is harder than you might think

Are the Colors in Astronomical Images ‘Real’?
In colorful photographs of galaxies, stars, planets, and more, what you see isn’t necessarily what you get

How to Watch the Total Lunar Eclipse on March 13
The March 13–14 lunar eclipse will be an all-night affair you won’t want to miss

If Aliens Looked at Earth from Far Away, What Might They See?
The question of whether aliens can detect our modern civilization depends on what signs they’re looking for—and, crucially, their distance from us

What’s on the Milky Way’s Far Side?
With radio and infrared telescopes, astronomers can pierce the dusty veil of our galaxy and map its farthest reaches

JWST Spies a Giant Space Hamburger—and Maybe Planetary Origins, Too
It’s neither fast nor food, but a spectacular object called HH 30 looks appetizing for astronomers in a new image from the James Webb Space Telescope

How Can We Know If an Asteroid Will Hit Earth?
“Keep your eye on the ball” is a motto for many athletes—and for astronomers trying to find Earth-threatening space rocks

How Many Planets Are in the Solar System?
The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define

Saturn’s Rings Are Disappearing—But They’ll Be Back
This year, from Earth’s perspective, Saturn’s rings will appear nearly edge on, making them almost invisible

NASA’s Hubble Space Telescope Was Never Meant to Look at the Sun. Astronomers Tried It Anyway
A little-known chapter of the Hubble Space Telescope’s history is a reminder of the risks of looking at the sun

Here’s What to Watch in 2025’s Skies
The heavens will provide a bounty of viewing treasures in the coming year

What Is the Zodiac—And What Does It Mean for You?
The familiar zodiac constellations are defined by Earth’s motion around the sun, but they don’t define your fate

An Earth-Rocking Cosmic Explosion Turns 20
Twenty years ago today a magnetar’s epic tantrum made our planet ring like a bell from tens of thousands of light-years away

What’s in a (Star’s) Name?
With billions of stars in the Milky Way, some nomenclature standardization is necessary

How Do Astronomers Navigate the Sky?
The celestial equivalent to latitude and longitude lets astronomers find their way across the heavens