And, at some point, did the Milky Way lose ours? There are some 400 billion objects flying through the Milky Way galaxy with enough mass that — if they were all made of […]

We can describe what we see happening, but we don’t understand why. Despite our vast cosmic knowledge, enormous unknowns remain. The quantum fluctuations inherent to space, stretched across the Universe […]

At just 3 solar masses, it eliminates the “mass gap.” Searching for black holes is one of the most difficult astronomical games a scientist can play. Emitting no light of their […]

Mass determines a star’s fate… except when it doesn’t. Supernova events are common, visually spectacular astronomical cataclysms. In 1987, a supernova just ~168,000 light-years away was observed in the Large Magellanic […]

Even 13.8 billion years after the Big Bang, we can reconstruct the first 3 minutes. About 100 years ago, we began to truly understand the nature of the Universe for the […]

If you want to know what the Universe is like, you have to look at it in the right way. Only by observing it can we know what the Universe is […]

The densest objects that haven’t collapsed to black holes can tell us information about the Universe unlike anything else. Swarming through our own galaxy, we’ve detected quite a few bizarre objects: […]

Enough mass in one location will always create a black hole. But not all masses are possible. If you take enough mass and compress it into a small enough volume […]

We need more and better data to know, but that’s exactly what’s coming. Over the past few decades, a number of important advances have helped revolutionize our picture of the Universe. […]

Only 17 years after its discovery have we learned we’re safe from asteroid Apophis. Ever since its 2004 discovery, asteroid 99942 Apophis has threatened planet Earth. Asteroid Apophis has been measured […]

When you measure not just light, but light’s polarization, you learn so much more. It’s been over 100 years since the first solution for a black hole was discovered in General […]

Something isn’t adding up, but it isn’t a calibration error. It’s been nearly 100 years since we discovered that the Universe was expanding. Ever since, the scientists who study the […]

Both views are equally spectacular, but unequally informative. Every so often, a creative amateur project highlights our professional achievements. This mosaic shows the region between the constellations of Cygnus and […]

The most massive nearby stars could be the seeds our supermassive black holes need. The problem with the Universe, as we see it today, is that we only get a snapshot […]

One image can give over 100 times the data we now get from Hubble. NASA’s Hubble Space Telescope, launched in 1990, revealed the previously unseen Universe. The most distant galaxy ever […]

We still don’t know what dark matter is, but at least we now know what it’s not. When it comes to science, we often say that it only takes a single […]

And what might we learn as we collect new, never-before-seen data? If you took one of history’s top scientists from 100 years ago and dropped them into today’s world, what […]

The Universe’s idea of a ‘typical star’ has changed dramatically over time. When you look out at the Universe today, you’re not seeing it exactly as it is at one particular […]

The Crab Nebula goes back to 1054, opening a window into our cosmic past. On July 4, 1054, Chinese astronomers recorded a “guest star” in the Taurus constellation. A ‘guest star’ […]

Dark matter was thought to be cold and collisionless. But maybe that’s not the full story. If you look out at the Universe and measure all the matter out there, including […]

By the end of the decade, we may discover one million black holes. A large enough mass in a compact volume inevitably forms a black hole. Both inside and outside the […]

The definitive answer requires better, unbiased data. Despite all the advances that have occurred in human history, one extraordinary puzzle still remains right in our own backyard: we aren’t sure how […]

Debris from Pluto-sized collisions, not aliens, are streaming through the galaxy. In 2017, scientists discovered an object passing through our Solar System that was unlike anything else we had ever seen. […]

NASA’s SOFIA mission is upgraded and back in action, and the Cigar Galaxy makes a perfect target. In theory, cold, neutral gas is the key to stars and galaxies. A visualization […]

Being a small piece of a large experiment is vital to the enterprise of science. Have you ever wondered what it’s like to work as a small (but vital) part of […]

The inevitable long, slow decline is accelerating, and there’s nothing we can do. The Universe, as it is today, is less active, is forming fewer stars, and is creating fewer chances […]

Science was never the same after meeting ‘the particle who lived.’ Back in the early 1930s, there were only a few known fundamental particles that made up the Universe. If you […]

Just say no to artist’s illustrations. This is what the Universe actually looks like. The Universe we observe often surpasses our greatest imaginings. This 20-year time-lapse of stars near the center […]

Avi Loeb says it’s aliens. Every other astronomer disagrees. Here’s why. In 2017, an astronomical event occurred that was unlike any other: for the first time, we observed an object that […]

Think there are habitable super-Earths out there? Think again. Here in our Solar System, we have two very distinct types of planets: small, terrestrial, rocky worlds, with thin (or no) atmospheres […]