Earth’s magnetic field protects us from deadly space radiation. What if it were drastically weakened, as a precursor to flipping upside down? I mean, it has before … many, many times..

Spaceship Earth has a literal deflector...

Every astronomy textbook tells us that soon after the Big Bang, there was a period of exponentially accelerating expansion called cosmic inflation. In a tiny fraction of a second, inflationary expansion multiplied the size of the...

Do you want to major in Astrophysics? Are you thinking about becoming (or ever just wondered how one becomes) an Astrophysicists? Do you want to know Matt O’Dowd’s origin story? Then buckle up and enjoy the ride and try your astrophysics...

The holy grail of physics is to connect our understanding of the tiny scales of atoms and subatomic particles with that of the vast scales of planets, galaxies, and the entire universe. To connect quantum physics with Einstein’s general...

The power of Dark Energy may be increasing as the universe ages. Subtle clues are emerging that the accepted model for the nature of dark energy and dark matter may not be all that. We saw the first such clue recently in our recent...

Our universe seems pretty complicated. We have a weird zoo of elementary particles, which interact through very different fundamental forces. But some extremely subtle clues in nature have led us to believe that the forces of nature were...

We already have the technology to bring humans safely to Mars and set up small settlements - or at least could do within a generation. But those settlements will need to be cocooned - shielded against the deadly cold, intense radiation,...

The universe is expanding, and that expansion is accelerating. We don’t know what’s causing that acceleration, but that hasn’t stopped us from giving it a name. We call this unknown influence dark energy. The observed acceleration is,...

Reality has cracks in it. Universe-spanning filaments of ancient Big Bang energy, formed from topological defects in the quantum fields, aka cosmic strings. They have subatomic thickness but prodigious mass and they lash through space at...

We humans have always been explorers. The great civilizations that have arisen across the world are owed to our restless ancestors. These days, there’s not much of Earth left to explore. But if we look up, there’s a whole universe out...

Our universe started with the big bang. But only for the right definition of “our universe”. And of “started” for that matter. In fact, probably the Big Bang is nothing like what you were taught.

A hundred years ago we discovered...

We know that gravity must cause clocks to run slow on the basis of logical consistency. And we know that gravity DOES cause clocks to run slow based on many brilliant experiments. But I never explained WHY or HOW gravity causes the flow...

So, how do you take a picture of a black hole? The beast in question is the supermassive black hole in the center of this – the M87 elliptical galaxy. It has an estimated mass of several billion times that of the Sun, which gives it an...

In astronomy we study things that are very far away. It’s a powerful challenge because even the brightest objects are almost impossibly faint when you view them from the other side of the universe. But there’s an up side. If the light...

Fast Radio Bursts were puzzling physicist for quite some time. They were thought to be the result of large cataclysmic events such as supernovae, but this theory was proven wrong when it was discovered that they could repeat themselves....

How do you see the unseeable - how do you explore the inescapable? Our cleverest astronomers have figured out ways to catch light that skims the very edge of black holes. Let’s find out what they learned.
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A few weeks ago a...

Black holes are about the worst subjects for direct study in the universe. But at this stage, it’s all we can do to convince ourselves of their existence. Actually studying the physics of real black holes is much, much harder. I mean, we...

Black holes are really only dangerous if you get too close. Ha, who am I kidding. It turns out they may be responsible for ending star formation across the entire universe.
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When we first realized that black holes could have...

The discovery of the Higgs boson ten years ago in the Large Hadron Collider was the culmination of decades of work and the collaboration of 1000s of brilliant and passionate people. It was the final piece needed to confirm the standard...

The weird rules of quantum mechanics lead to all sorts of bizarre phenomena on tiny scales— particles teleporting through walls or being in multiple places at once or simultaneously existing and not. Shame all this magical behavior...

When we detected the very first gravitational wave, a new window was opened to the mysteries of the universe. We knew we’d see things previously thought impossible. And we just did - an object on the boundary between neutron stars and...

It’s about time we discussed an obscure concept in physics that may be more fundamental than energy and entropy and perhaps time itself. That’s right - the time has come for Action.

When we scan the heavens with giant telescopes we see galactic cannibalism everywhere. We see moments that appear frozen on the human timescale, but are really snapshots of the incredibly violent process of galaxy formation. This is how...

It may be that for every star in the universe there are billions of microscopic black holes streaming through the solar system, the planet, even our bodies every second. Sounds horrible - but hey, at least we’d have explained dark matter.