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Cosmology
Why does dark matter, if it doesn’t dissipate energy, become gravitationally bound at all? One of the most puzzling components of the Universe has to be dark matter. Although we have […]
The anthropic principle has some fascinating scientific uses. And abuses, too. For thousands of years, humans have pondered the meaning of our existence. From philosophers who debated whether their minds could […]
The Twin Jet nebula, shown here, is a stunning example of a bipolar preplanetary nebula. At the center, a dying star is in the final stages of life where it […]
We just found a system that we can’t explain. Here’s what’s going on. One of the most fascinating facts about the Universe is that there’s so much of it out there. […]
We’re still not sure what the ultimate question is. Here are 5 excellent candidates. One of the most amusing stories in all of science fiction is Douglas Adams’ The Hitchhiker’s […]
Could this finally be the clue we’ve hoped for in uncovering the truth about dark matter? In the physical sciences, theory and observation are supposed to work hand-in-hand. Theorists work out […]
If we waited long enough, would even protons themselves decay? There are certain things in the Universe that, if you leave them alone for long enough, they’ll eventually decay away. […]
Is the “big freeze” our inevitable fate, or can dark energy save us? When we look out at the Universe today, we see sources of light practically everywhere we look. In […]
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 […]
We may be different in many ways, but the cosmic story is the same for each of us. In all the Universe, you won’t find another planet identical to Earth. Planet […]
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 […]
Just because you have “star” in your name doesn’t mean you are one. When we think about the objects in our Universe, they fall into two categories: self-luminous objects, like stars, […]
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 […]
Black holes are the darkest objects of all. But are they made of dark matter? When it comes to the Universe, few objects are more compelling, fascinating, or extreme than black […]
When two black holes that shouldn’t exist are seen merging, physics has some explaining to do. After years of searching for gravitational waves, it finally happened: LIGO bagged the biggest one […]
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 […]
If they have mass, then why don’t we see any slow-moving ones? For decades, the neutrino was among the most puzzling and elusive of cosmic particles. It took more than […]
The largest moon around our last planet didn’t originate with Neptune. When it comes to the moons of our Solar System, there’s only one planet that doesn’t fit in with our […]
There was a time in the Universe before we formed stars. Here’s how we’re exploring it. When we look out at the Universe today, we see that it’s full 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 […]
The Big Bang started it all. And then we realized there was more. Of all the questions humanity has ever pondered, perhaps the most profound is, “where did all of this […]
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 […]
It’s fundamentally different from space. Here’s how. Here’s a question that most of us have been asked at some point in our lives, “what’s the shortest distance between two points?” By […]
When one group says “A” and another group says “B,” consider that everyone might be wrong. One of the biggest enemies of scientific truth is the setup of a false dichotomy. […]
They’re one of the brightest windows into our Universe’s star-forming past. When we look out at the galaxies in the Universe, almost all of them have supermassive black holes at […]
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 […]
It comes from a supernova seen just 33 years ago, and it doesn’t pulse. 33 years ago, a supernova occurred just 168,000 light-years from Earth. This new image of the supernova […]