It’s much more complex a question than dividing its mass by the volume of the event horizon. If you want to get a meaningful answer, you have to go deep. If […]

Every object in the Universe is constrained by the laws of physics. Does this mean there are any black holes that shouldn’t exist? When it comes to the objects that […]

What’s more massive than the heaviest known neutron star but lighter than the lightest known black hole? LIGO may be about to solve that mystery. Whenever a star is born in […]

You’ve seen a black hole’s event horizon for the first time thanks to them. But they’re only getting started. Earlier this year, 2019, the Event Horizon Telescope collaboration revealed the first […]

Black holes are regions of extreme gravity, but dark matter barely interacts at all. Do they play well together? Black holes are some of the most extreme objects in the […]

We’re one step closer to solving the mystery of how they get so big so fast. A great cosmic mystery for science is explaining how supermassive black holes form. An ultra-distant […]

Many of them are spinning at nearly the speed of light. When you do the math, there’s no other way it could have been. Take a look out there at the […]

The dream of multi-messenger astronomy is to seen an event with gravitational waves, neutrinos, and light all together. The newest candidate just might get us there. When it comes to cataclysmic […]

A star orbiting past our galaxy’s supermassive black hole offered a chance to test relativity as never before. The supermassive black hole at the center of the Milky Way is the […]

The quest for a quantum theory of gravity is the holy grail of physics. Here’s why it’s murkier than anyone expected. If you want to fully describe how the Universe […]

The Planck length is a lot smaller than anything we’ve ever accessed. But is it a true limit? If you wanted to understand how our Universe operates, you’d have to examine […]

Discovered by NASA’s Chandra X-ray observatory, it’s powered by a supermassive black hole. 2019 marks 20 years of NASA’s Chandra, humanity’s most powerful X-ray observatory. Artist illustration of the Chandra X-ray […]

A vacuum cleaner is the wrong picture. Time to bust that myth. There are no classes of object in our Universe more extreme than black holes. With so much mass present […]

An entire Universe of possibilities await stars like our own, even after they run out of fuel. One of the most profound rules in all the Universe is that nothing lasts […]

There aren’t any holes in the Universe at all. What actually exists is far more interesting. Somewhere, far away, if you believe what you read, there’s a hole in the […]

13.8 billion years isn’t close to enough time, but if we wait long enough, even our Sun will become one. The Big Bang happened approximately 13.8 billion years ago, and it […]

It’s made up of scores of telescopes at many different sites across the world. But it acts like one giant telescope. Here’s how. If you want to observe the Universe more […]

If a star spins and then collapses, what happens to its angular momentum? The most common way to form a black hole in the Universe is to have a massive […]

Now that we’ve seen our first one, we want more, and we want them better. Here’s how to get there. To resolve any astronomical object, you must achieve resolutions superior to […]

It’s the technique, from the Event Horizon Telescope, that brought us a black hole’s image. Here’s how it works. The Event Horizon Telescope has accomplished what no other telescope or telescope […]

And what do we still have left to learn? The original idea of a black hole goes all the way back to 1783, when Cambridge scientist John Michell recognized that a […]

The first image of an Event Horizon is here. Here’s what it means. Variety isn’t just the spice of life, but a natural consequence of living in our Universe. Gravitation, obeying […]

We’ve never seen an image of a black hole’s event horizon before. Here’s what we’re expecting, based on what we already know. For hundreds of years, physicists have hypothesized that the […]

What should a black hole look like? Our theoretical predictions are about to meet our first observations. In science, there’s no moment more exciting than when you get to confront […]

The visible light portion of the spectrum is tiny compared to the whole thing. Here’s what we’re missing. When you look at the Milky Way in visible light, you might see […]

LIGO and Virgo have now detected a total of 11 binary merger events. But exactly 0 were in the Milky Way. Here’s why. One of the most spectacular recent advances in […]

In order to reap the greatest rewards, we have to think big and invest big. One of these four missions will deliver like never before. When it comes to exploring the […]

Even if we don’t destroy ourselves, we always have the Universe to contend with. Wiping out all life on Earth is hard, but causing mass extinctions is easy. The 1991 eruption […]

Gravity gets weaker as the distance squared. But gravitational waves only get weaker as the distance. Why? One of the things we often just accept about the world is that […]

In 2017, we saw gravitational waves a neutron star merger for the first and only time. And it keeps getting more interesting. On August 17, 2017, a cosmic signal arrived […]