Regulus Star: The Little King at the Heart of Leo the Lion

Look toward the constellation Leo on a spring evening and you will find a single blue-white point of light sitting at the base of...

What Is a Constellation? A Beginner’s Guide to the Sky’s 88 Star Patterns

A constellation is a group of stars that forms a recognizable pattern in the night sky, one we've given a name, usually after a mythological figure, animal, or object. There are 88 of them officially recognized, and together they map out the entire sky....

How Many Planets Are There? The Real Answer Is Bigger Than Eight

There are eight planets in our solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn,...

What Is a Galaxy? A Simple Guide to the Great Islands of Stars

A galaxy is an enormous collection of stars, gas, dust, and dark matter, all...

Einstein Said This Would Never Be Detected. He Was Off by 100 Years.

At 5:51 a.m. Eastern time on September 14, 2015, a signal lasting a quarter...

What Is Dark Energy? The Mysterious Force Pulling the Universe Apart

In just two weeks, NASA is launching a telescope specifically built to chase down...

How Far Is the Sun From Earth? The 93-Million-Mile Answer and Why It Keeps Changing

The Sun sits an average of about 93 million miles (150 million kilometers) from...

How Old Is the Universe? The 13.8-Billion-Year Answer and How We Measured It

The universe is about 13.8 billion years old. More precisely, 13.787 billion years, give...

How Old is the Oldest Thing on the Planet from Our Solar System?

Ever look up at the night sky and wonder what's actually the oldest thing on the planet, or even in the whole solar system?...

She Measured the Universe. Nobody Let Her Touch a Telescope.

Henrietta Leavitt spent her career at Harvard doing work considered too tedious for the...

The Orion Nebula (M42): A Stellar Nursery You Can See With Your Own Eyes

Most of the jaw-dropping objects in deep space are hopelessly out of reach. You...

How Many Planets Are There? The Real Answer Is Bigger Than Eight

There are eight planets in our solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn,...

Galaxies & Deep Space

Supermoon: What It Really Is, Why It Happens, and When to Catch the Next One

A supermoon is a full moon that lines up with the Moon's closest approach...

What Is a Constellation? A Beginner’s Guide to the Sky’s 88 Star Patterns

A constellation is a group of stars that forms a recognizable pattern in the...

How Many Planets Are There? The Real Answer Is Bigger Than Eight

There are eight planets in our solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn,...

What Is a Galaxy? A Simple Guide to the Great Islands of Stars

A galaxy is an enormous collection of stars, gas, dust, and dark matter, all...

How Far Is the Sun From Earth? The 93-Million-Mile Answer and Why It Keeps Changing

The Sun sits an average of about 93 million miles (150 million kilometers) from...

The Mars Rover’s Last Words: The True Story Behind “My Battery Is Low and It’s Getting Dark”

There's a line about a dying robot on Mars that has made grown people...

How Far Is the Moon From Earth: The Real Distance and Why It Keeps Changing

The Short Answer On average, the Moon sits about 384,400 kilometres from Earth, which is...

Why Does Saturn Have Rings But Earth Doesn’t Explained

Have you ever gazed at the night sky and wondered about the majestic beauty...

What is Hoag’s Object?

If you scan through deep space photos taken by the Hubble Space Telescope, most...

The 12 Zodiac Constellations: The Real Astronomy Behind the Star Signs

Everyone knows their star sign. It's on birthday cards, dating profiles, and the back...

What Are Saturn’s Rings Made Of? The Icy Truth Behind the Solar System’s Most Famous Feature

Ask a kid to draw a picture of a planet and theres a solid...

What Can You See in the Night Sky Without a Telescope Tonight

Many people think you need expensive gear to explore space. Friends often say they...

Astronomers Just Found Three Supermassive Black Holes Sharing One Galaxy

Most large galaxies host exactly one supermassive black hole at their center. A galaxy...

Observe the Sky’s Colorful Stars: A Beginner’s Stargazing Guide

Most people's mental image of the night sky is pretty simple, a scattering of...

Planets

Discover 10 Space Facts That Sound Fake But Are True

Have you ever wondered if the universe is playing a trick on your imagination? While we often look at the night sky as a calm, predictable void, the reality of our cosmos is far more bizarre than any science fiction novel. Modern astronomy constantly reveals...

Four Hypothetical Stars So Strange Scientists Still Aren’t Sure They’re Real

Most of what we know about stars fits into a fairly predictable pattern, they're...

Types of Galaxies: Spiral, Elliptical, and Irregular Explained

Every galaxy you've ever seen a photo of falls into one of a small...

What’s the Difference Between a Galaxy and a Solar System?

These two terms get mixed up constantly, and honestly, it's an easy mistake to...

How Far Is the Moon From Earth: The Real Distance and Why It Keeps Changing

The Short Answer On average, the Moon sits about 384,400 kilometres from Earth, which is...

Space Missions

Meet the 10 Nearest Stars to Our Solar System

Look up at a truly dark sky and you're seeing light from thousands of stars, but almost none of them are actually close. In...

The Moon Phases Explained: A Simple Guide to Why the Moon Changes Shape Every Night

Look up at the Moon on two different nights and it can seem like...

How Far Is the Sun From Earth? The 93-Million-Mile Answer and Why It Keeps Changing

The Sun sits an average of about 93 million miles (150 million kilometers) from...

The Closest Black Holes to Earth, Ranked

Somewhere in the Milky Way, roughly 100 million stellar-mass black holes are drifting through the galaxy right now. Astronomers have confirmed a small handful of them. Here's exactly how close the nearest ones actually sit, and why you shouldn't lose any sleep over it. The...

How Long Is a Year on Saturn? The Ringed Planet’s Orbit Explained

Have you ever wondered what your birthday would look like if you lived on Saturn? You probably wouldn't be celebrating very often. So, how long...

Planet Earth

Does Venus Have Moons: Why Earth’s Twin Is a World Without a Single Moon

The Short Answer No, Venus has no moons at all. Zero. Along with Mercury, it's...

Is Pluto a Planet: The Real Story Behind the Solar System’s Most Famous Demotion

The Short Answer No, Pluto is no longer classified as a planet. In 2006 the...

Mars Gravity Compared to Earth: What You’d Really Weigh on the Red Planet

Picture yourself stepping off a lander onto the rusty dust of Mars. First thing...

What Is a Pulsar? The Spinning Stellar Lighthouses of the Galaxy

In the summer of 1967, a 24 year old graduate student named Jocelyn Bell...

The Photo That Needed an Earth-Sized Camera to Take

Nobody had ever seen a black hole. Not because telescopes weren't powerful enough in the ordinary sense, but because the object researchers wanted to photograph was 55 million light-years away and so compact that capturing it would be, as one scientist put it, like...

All Articles

The Closest Black Holes to Earth, Ranked

Somewhere in the Milky Way, roughly 100 million stellar-mass black holes are drifting through...

Which Planets Have Rings? Saturn Isn’t Even the Biggest One

Ask most people which planet has rings, and Saturn is the only answer you'll...

Is There Life on Other Planets? Here’s What the Evidence Actually Shows

NASA puts it about as plainly as an agency can: so far, the only...

Planets in Order: The Complete Guide to Our Solar System

Eight planets orbit the Sun, and their order never changes: Mercury, Venus, Earth, Mars,...

A Galaxy Named After a Vegetable Just Turned Out to Have Two Feeding Black Holes Inside It

Astronomers have a habit of naming things exactly what they look like, and Green...

Cassini Has Been Gone for Eight Years. It’s Still Making Discoveries.

Cassini deliberately burned up in Saturn's atmosphere back in September 2017, ending its mission...