Cosmology

Cosmology

If you traveled in a straight line for far enough, would you come back to where you started? If you were to set out on a journey from anywhere on Earth’s […]
Find a clear western horizon after sunset, and this ‘triple treat’ of a dance can be yours. Every once in a while, the night sky provides a spectacular feast for our […]
There are three things your new theory must do in order to be taken seriously as science. This one’s 0-for-3. Every once in a while, a revolutionary idea comes along that […]
There’s a million things we haven’t done. But just you wait. The Universe as we know it began some 13.8 billion years ago with the onset of the hot Big Bang. […]
On the largest scales, dark matter holds the Universe together. But on small ones, it helps reveal exactly what it is… and isn’t! Dark matter is often thought of as the […]
All the things that surround us and make us up weren’t always here. But where did it all come from? The Universe, as we see it today, sure is full of […]
We all share atoms with every person, living or dead, on Earth. There’s more in common among us than you might think. When you eat food, drink liquids, or even breathe […]
A generation ago, NASA launched their great observatories to explore the Universe. It’s time for round 2. Throughout the history of astronomy, every advance we’ve ever made has come about because […]
It’s 100 years since astronomy’s famous ‘great debate.’ We still haven’t learned the most compelling lesson of all. So, you’ve arrived at a crossroads: you think the world works in a […]
It should be just as sticky (or non-sticky) as normal matter. Here’s how we know. Not only here on Earth, but everywhere in the Universe that we look, we find structures […]
Over the past 30 years, we’ve revolutionized what we know about the Universe. But we couldn’t have done it without these lessons. On April 24, 1990, the Hubble Space Telescope rocketed […]
The dream of an ‘Earth-like’ planet showcases our astrobiological ignorance. Over the past decade, our understanding of what planets exist around stars other than our own has exploded. The number […]
Its record-holding galaxy is 32 billion light-years away, in a Universe that’s only 13.8 billion years old. On April 24, 2020, humanity celebrates the 30th anniversary of NASA’s Hubble Space Telescope. […]
We might live in a quantum Universe, but we’ll violate the principle of relativity if space is discrete. If you try and divide matter into smaller and smaller chunks, you’ll […]
The original Hubble Deep Field truly showed us what the Universe looks like. Later this month, the Hubble Space Telescope will celebrate its 30th anniversary. This photo of the Hubble Space […]
There are three factors all competing to determine the fate of the Earth, and the one that’s winning now won’t win in the end. If you could measure the average distance […]
In 774/775, tree rings show a spike in carbon-14 unlike anything else. At last, scientists think they know why. Every once in a while, science gives us a mystery that comes […]
We’re not made out of the densest elements, but we’re the densest planet nonetheless. Here’s why. Of all the planets, dwarf planets, moons, asteroids and more in the Solar System, only […]
Hawking radiation should really be happening, but black holes are farther from decaying than ever before. Black holes are, in many ways, the most extreme objects that will ever exist in […]
It’s not just for Earth-like planets around Sun-like stars. Not even close. Shortly after Earth first formed first formed, life quickly took hold, thriving ever since. Both reflected sunlight on a […]
It isn’t just that mass and energy are equivalent and interchangeable. It tells us something fundamental about mass itself. Of all the equations that we use to describe the Universe, perhaps […]
A year ago, a puzzling gap existed between black holes and neutron stars. With nearly a year of new data, LIGO solves the puzzle. On Monday, March 16, 2020, astrophysicist Carl […]
Today, our observable Universe extends for 46 billion light-years in all directions. But early on, things were much smaller. There are few things we can conceive of that are as mind-bogglingly […]
And if you have a friend at the same longitude, you can even measure its circumference. This year’s equinox, on March 19/20 of 2020 (longitude-dependent), is Earth’s earliest in 124 […]
You’d have to throw out a lot of known physics for this to even be a possibility. Here’s why. It’s an undeniable scientific fact that dark matter must exist in order […]
Dark matter is perhaps the most mysterious substance in the Universe. What exactly it is, however, still eludes us. Dark matter is one of the most mysterious and yet most ubiquitous […]
No one has seen an equinox this early since the 19th century. And you’d better get used to it. This year, on March 19, 2020, the equinox will occur. For a […]
After the Big Bang, merging supermassive black holes are unparalleled. Here’s how we’ll find the first one. Last week, NASA’s Chandra X-ray observatory made history by announcing the most energetic explosive […]
It isn’t just a day that comes every four years; it’s everything we need to keep our calendar aligned with Earth’s orbit. Once every four years, at least under most circumstances, […]
Ever wonder, exactly, how stars form from molecular gas and dust? So do scientists. One of the great challenges for astronomy is to determine, in gory detail, how stars are […]