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It wasn’t the birth of space and time. But it was truly essential to our cosmic story. For more than 50 years, we’ve had definitive scientific evidence that our Universe, as […]
California’s Bobcat Fire has reached Mount Wilson Observatory’s doorstep. 100 years ago, our understanding of the Universe was very different from what it is today. Einstein’s General Relativity, our theory […]
There are only 3 populations of stars, but “generations” is a more complex question. When we look out at the stars in the Universe, we classify them into three different […]
Have any of the stars we can see burned themselves out completely? When we look out across the Universe, we’re also peering back in time. In the early 21st-century, we’ve […]
In 2006, the IAU demoted Pluto. Here’s what we know today. In 2006, the last planet in our Solar System suffered an unforgettable insult, as Pluto — known for generations as our ninth […]
The view is different for each of us, but this perspective unites us all. From anywhere on Earth, the entire sky rotates a full 360° every 24 hours. From Earth, star […]
The pendulum didn’t tick right when they brought it here: the start of a fascinating story. For nearly three full centuries, the most accurate way that humanity kept track of […]
There was less than a 2 second delay between gravitational waves and light, but that’s incredibly meaningful. There’s an important rule in relativity that — as far as we know — all objects must […]
Just because something’s unlikely doesn’t mean that anything’s wrong. In our quest to understand the Universe, theoretical physics is perhaps the most powerful tool we have as far as making […]
It likely isn’t the rare occurrence we once thought it was. In our Solar System, there’s one overwhelming source of mass that all the planets orbit around: our Sun. Each planet […]
As the Universe ages, will it eventually fade away entirely? The earliest signal we’ve ever directly detected from the Universe comes to us from shortly after the Big Bang: when […]
Everything is being driven apart. But there’s hope of reaching what’s currently so far away. For the first 7.8 billion years, the Universe unfolded exactly as scientists would have expected in […]
There could have been life on Mars in the past, but that’s only the beginning of the story. For as long as humanity has been watching the skies, we’ve been fascinated […]
Some of them may have formed just 200 million years after the Big Bang. When we look out at the Universe, we’re not seeing objects as they are today, but rather […]
There are exposed planetary cores orbiting stars, and we may have already found them. When we take a look at the planets in our Solar System, there’s a pretty clear difference […]
There’s a boundary to how far back we can observe everything that exists. Despite everything we’ve learned about our Universe, there are many existential questions that remain unanswered. We don’t know […]
Our galactic home in the cosmos — the Milky Way — is only one of two trillion galaxies in the observable Universe. Our galactic home in the cosmos — the Milky Way — is merely one among the […]
For the first time in many years, there’s currently a comet visible to the naked eye in Earth’s night sky: comet NEOWISE. For the first time in many years, there’s currently […]
For northern hemisphere skywatchers, it might just be the century’s best comet so far. Every once in a while, large, icy objects pass through the inner Solar System. C/2014 Q2 (Lovejoy) […]
We still don’t know how it came to be this way. Every once in a while, we find an object in the Universe that completely mystifies us. For generations, astronomers have […]
Here’s how the closest place to “hell” in our Solar System might actually be home to life. From afar, Venus seems like the most uninhabitable planet of all. NASA’s Magellan mission […]
The theoretical reasons to expect it are compelling, but the technology required to detect it is unfathomable. All throughout our galaxy, millions of black holes of a variety of masses […]
There’s a lot left to understand, ponder, and investigate. And there always will be. For hundreds of thousands of years — nearly all of human history — we had no definitive answers to some of […]
From the right place at the right time, it’s a sight unlike any you’ll find on Earth. In our Solar System, any planet with moons has a chance for a solar […]
It’s perhaps the most famous thought experiment in all of physics, but is full of popular myths and misconceptions. One of the most bizarre ideas about the quantum Universe is […]
Without a little help from Einstein, we couldn’t have made this discovery. NASA’s Hubble Space Telescope, currently celebrating its 30th anniversary, still churns out novel discoveries. The Hubble eXtreme Deep […]
This year’s June solstice coincides with a new Moon and an annular solar eclipse. Here’s how rare it truly is. As the Earth orbits the Sun, it rotates on its axis. […]
Nothing in the Universe can travel faster than the speed of light. So how does space itself do it? One of the fundamental rules we all learn in physics — set forth by […]
Too little breathing room, tear gas, and insufficient masks are a recipe for disaster. Police are worsening all three. Across the nation and the world, people of all skin colors are […]
Solid, liquid, and gas are the three everyone learns. Plasma is the fourth. But there are two more, and they’re fascinating. How many states of matter are there? When you […]