The most massive star in the known Universe is 260 times as heavy as our Sun. But viewing the early Universe will shatter that record. Place enough mass together in one […]

Before there were humans, planets, or even stars and galaxies, we had to make the first elements. Here’s how they happened. From the first moments of Big Bang to the […]

Different measurements of the Universe’s rate of expansion give inconsistent results. But this simple solution could fix everything. In 1915, Einstein’s theory of General Relativity gave us a brand new […]

With every second that goes by, tens of thousands of star disappear from our reach. And it’s getting worse. It’s been nearly a century since scientists first theorized that the Universe […]

The Universe is an enormous place, but we can’t see all the way back to the beginning. Here’s the latest record-breaker. No matter how far back we look in the […]

Space may be enormous, but collisions are inevitable. Here’s what happens when they occur. The Universe as we know it has been around for nearly 14 billion years: plenty of time […]

The ices and rock aren’t green, and neither are the tails. So where does a comet’s green color come from? Every so often, with extreme regularity, comets will plunge from beyond […]

NASA’s Cassini spacecraft taught us more than we ever imagined about Saturn. Could we do something similar for Uranus and Neptune? From where we are in the Solar System, looking out […]

The story of John Couch Adams, “the man who failed to discover Neptune,” and his cosmic redemption. Perhaps its human nature to want to only think positive thoughts about our […]

Three great things all align this August, making the Perseids a can’t-miss show. Here’s how to take advantage. When it comes to meteor showers, we have these dazzling pictures in […]

Mars will never look as big as the full Moon. But it isn’t even the biggest planet. From humanity’s perspective, the Sun and Moon always dominate Earth’s skies. The Moon and […]

It wasn’t just the Milky Way and Andromeda two billion years ago. Here in the Local Group, our two largest galaxies dominate: Andromeda and the Milky Way. Our Local Group of […]

Did the Universe begin at time t=0? Did space and time emerge from that? The Universe, today, is expanding and cooling, as the volume of the Universe increases while the number […]

Our best physical theories predict that a multiverse exists. But if we can’t test it, is it really scientific? The Universe is all there ever was, all there is, and […]

A new set of images from NASA’s Chandra X-ray observatory shows us what we’ve never seen before. The Pillars of Creation, 7,000 light years away in the Eagle Nebula, represents one […]

If we know how big the observable Universe is, why can’t we figure out how big the unobservable part is? 13.8 billion years ago, the Big Bang occurred. The Universe was […]

The most unusual star known has finally had its dimming scientifically explained. Here’s the unusual, dusty resolution. The science of planet-hunting has truly taken off in the 21st century, with […]

In 1987, we detected neutrinos from another galaxy in a supernova. After a 30 year wait, we’ve found something even better. One of the great mysteries in science is determining not […]

Before there were gravitational waves, multi-messenger astronomy got its start with the neutrino. Sometimes, the best-designed experiments fail. The effect you’re looking for might not even occur, meaning that a […]

The brightest galaxies of all neither have the most stars nor the biggest black holes. Here’s how to solve the mystery. With some 400 billion stars burning steadily, the Milky Way […]

How ‘special’ are we for life to have survived and thrived the way it did? While there are hundreds of billions of stars in our galaxy, many with Earth-sized planets at […]

Finding the ingredients for life is a very different prospect than finding the products of life. Perhaps the greatest quest in science today is to find life that originated beyond Earth. […]

There’s a halo of dark matter permeating every galaxy, and that means its particles pass through us, too. The Universe, despite all the planets, stars, gas, dust, galaxies, and more we […]

Forget the spectacular explosions we create here on Earth. The Universe outdoes us in every way imaginable. Forget mere chemical reactions; in space, matter-energy conversion creates unprecedentedly powerful explosive events. […]

Dark energy is pushing distant galaxies apart from one another at an increasing rate. If the Big Rip hypothesis is true, things will only get worse from here. One of the […]

Intelligent aliens, if they exist in the galaxy or the Universe, might be detectable from a variety of signals: electromagnetic, from planet modification, or because they’re spacefaring. But we haven’t […]

Many hoped we could do without dark matter. On cosmic scales, the evidence has finally spoken. For over 40 years, scientists have argued over dark matter’s existence. The extended rotation curve […]

The Universe is expanding, but different techniques can’t agree on how fast. No matter what, something major has got to give. Look out at a distant galaxy, and you’ll see it […]

If you thought LIGO’s recent discoveries were profound and unusual, wait until you meet OJ 287. Recently, LIGO has revolutionized our knowledge of the Universe by discovering merging black holes. The […]

When it comes to the Solar System, all we have left are the survivors. At last, that might be enough to know what happened 4.5 billion years ago. We know what […]