Depending on how you measure it, there are two different answers that could be right. If you want to see what’s out there in the Universe, you first have to be […]

The world’s greatest observatory can go no further with its current instrument set. The Hubble Space Telescope has provided humanity with our deepest views of the Universe ever. It has […]

Dark matter, dark energy, inflation and the Big Bang are real, and the alternatives all fail spectacularly. If you keep up with the latest science news, you’re probably familiar with […]

The small step that one man took would never have happened without this narrow escape. On July 20, 1969, history was made as humanity set foot on the Moon for the […]

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 […]

How fast is the Universe expanding? The results might be pointing to something incredible. If you want to know how something in the Universe works, all you need to do […]

Nothing is 100% safe or 100% effective, but vaccine-hesitancy is even worse. It’s one of the most important decisions you’ll ever make in your life: do I vaccinate my child, and […]

We’re a long way from the beginnings of life on Earth. Here’s the key to how we got there. The Universe was already two-thirds of its present age by the time […]

Who should sit atop the iron throne? Let your DNA decide. Here on Earth, we hold one important truth to be self-evident above all others: that all humans are created equal. […]

Our Sun will someday run out of fuel. Here’s what it will look like when that happens. The fate of our Sun is unambiguous, determined solely by its mass. If all […]

The whole should equal the sum of its parts, but doesn’t. Here’s why. The whole is equal to the sum of its constituent parts. That’s how everything works, from galaxies to […]

It might be the biggest conundrum facing cosmology today. But perhaps it’s not a controversy; it might be a clue. https://soundcloud.com/ethan-siegel-172073460/starts-with-a-bang-44-the-expanding-universe/ One of the biggest conundrums in the Universe surrounds the […]

And why Einstein’s quest for unification was doomed from the start. If you wanted to answer the question of what’s truly fundamental in this Universe, you’d need to investigate matter and […]

Xenon-124 isn’t stable, and the direct detection of its decay could lead us to an even greater prize. Our Universe is old: 13.8 billion years old, to be precise. Many of […]

Our outer Solar System, from Jupiter to Neptune, isn’t unique after all. In the early 1990s, scientists began detecting the first planets orbiting stars other than the Sun: exoplanets. The easiest […]

Our planet is rare, precious, and fragile. It’s up to all of us to be its steward. With the advent of rocketry and spaceflight, our cosmic perspective changed forever. The very […]

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 […]

There was a first molecule, and we found one just like it. But there’s a big difference. The Universe’s first molecule is found at last! That’s what the headlines have […]

Red, green, and blue? What we call ‘color charge’ is far more interesting than that. At a fundamental level, reality is determined by only two properties of our Universe: the quanta […]

A single thought experiment reveals a paradox. Could quantum gravity be the solution? Sometimes, if you want to understand how nature truly works, you need to break things down to […]

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 […]

Beyond the oceans boiling and the death of our Sun, Earth’s ultimate fate won’t be determined until far in the distant future. It took the Universe 13.8 billion years to create […]

When the Universe gives us clues, we ignore them at our own peril. When you approach the world scientifically, you seek to gain knowledge about how it works by asking it […]

If parallel Universes or the multiverse are real, we might someday encounter a visitor who hails from another one. Here’s what to do. There are a lot of things that are […]

We assume that life is ubiquitous in the Universe. But what if it’s just us? When it comes to the question of extraterrestrial life, humans optimistically assume the Universe is prolific. […]

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 […]