Ethan Siegel
A theoretical astrophysicist and science writer, host of popular podcast "Starts with a Bang!"
Ethan Siegel is a Ph.D. astrophysicist and author of "Starts with a Bang!" He is a science communicator, who professes physics and astronomy at various colleges. He has won numerous awards for science writing since 2008 for his blog, including the award for best science blog by the Institute of Physics. His two books "Treknology: The Science of Star Trek from Tricorders to Warp Drive" and "Beyond the Galaxy: How humanity looked beyond our Milky Way and discovered the entire Universe" are available for purchase at Amazon. Follow him on Twitter @startswithabang.
If your Universe contains any matter at all, a constant Hubble parameter is absolutely impossible. Our observable Universe is an enormous place, with some two trillion galaxies strewn across the […]
Many of them are spinning at nearly the speed of light. When you do the math, there’s no other way it could have been. Take a look out there at the […]
What makes Uranus and Neptune-like worlds so fascinating? If you only knew. What do we really know, and what mysteries are left to solve, about the outer worlds of our Solar […]
When you’re trying to peel back the veil obscuring the fundamental nature of matter, you have to look absolutely everywhere. Sometimes, the solution to a puzzle you’ve been stymied by […]
The dream of multi-messenger astronomy is to seen an event with gravitational waves, neutrinos, and light all together. The newest candidate just might get us there. When it comes to cataclysmic […]
And it’s not because of leap seconds; it’s a fundamental property of most days. Human beings, in marking the passage of time, account for each day equally: with 24 hours. One […]
It’s not a question of could they, but have they? Here’s how we’ll find out. It’s no secret that fragments of asteroids, comets, and other spaceborne objects have been found here […]
From the inflationary state that preceded the Big Bang to our cold, lonely, dark energy-dominated fate, the Universe goes through six different eras. We’re living in the last one already. The […]
A star orbiting past our galaxy’s supermassive black hole offered a chance to test relativity as never before. The supermassive black hole at the center of the Milky Way is the […]
Particle physics is everywhere, even in the palm of your hand. When you hold out your palm and point it towards the sky, what is it that’s interacting with your hand? […]
Our Universe cannot be described by normal matter alone. Vera Rubin’s work led the way. Ask an astrophysicist what our Universe is made of, and you’ll likely receive a shocking surprise. […]
It’s not volcanic activity, and it’s definitely not from a fire. Mars, our red planetary neighbor, is a vastly different world from Earth. Mars and Earth, to scale, shows how much […]
And does it require the idea of ‘negative gravity’ in order to work? The biggest question that we’re even capable of asking, with our present knowledge and understanding of the Universe, […]
Even with the best preparation imaginable, sometimes you have to get lucky, too. Even from our perspective in 2019, 50 years later, humanity’s achievements from July, 1969, still mark the pinnacle […]
A case for looking beyond the planetary scientist’s (or even the astronomer’s) definition. Ever since 2006, when the International Astronomical Union (IAU) officially defined the term planet — introducing the term ‘dwarf […]
You get out what you put in, and we haven’t truly invested in space since Apollo ended. Humanity should be an interplanetary civilization by now. There is no scientific reason that […]
Just because you can design an experiment to test for something doesn’t mean you should trust the results. Is there another Universe out there? The Universe we know and inhabit, the […]
Most of the Moon’s effects on Earth are small and imperceptible. But for the grunion, it’s absolutely essential. Although it’s the closest astronomical body to Earth, the Moon is still […]
It’s very different from the colloquial meanings of “true-and-false” or “right-and-wrong.” In many ways, the human endeavor of science is the ultimate pursuit of truth. By asking the natural world […]
Hunting for dark matter, neutrinos, and other elusive signals isn’t just a satisfying endeavor, it’s a way of life for Dr. Laura Manenti. We know that there’s more to the Universe […]
The nature of our quantum Universe is puzzling, counterintuitive, and testable. The results don’t lie. Although our intuition is an incredibly useful tool for navigating daily life, developed from a lifetime […]
The Soviet Union’s space program was years ahead of the USA’s. So how did they lose the space race? Here in the United States and all across the world, humanity is […]
Physicists sure do give counterintuitive names to the things they find. Most of us are confounded by the idea of relativity when we first encounter it. Objects don’t just move through […]
Not only can’t astronomers and planetary scientists agree, but the IAU made it worse for everyone. If you were alive in 2006, you likely remember a momentous event in astronomy: […]
When stars get ejected from galaxies within massive clusters, they go where the dark matter is. Dark matter is one of the greatest mysteries in the Universe, displaying its effects in […]
General Relativity has nothing to do with light or electromagnetism at all. So how to gravitational waves know to travel at the speed of light? There are two fundamental classes of […]
The laws of physics are not time-reversal invariant. Here’s how we know. No matter when, where, or what you are in the Universe, you experience time in only one direction: forwards. […]
From explosions to their unique and vibrant colors, the fireworks displays we adore require quantum physics. This Thursday, July 4, 2019, is remarkable for a number of reasons. It happens to […]
It’s found everywhere we know how to look, and just might be nature’s perfect fuel. Here’s how to harness it. Dark matter is one of the biggest mysteries in all of […]
No matter how long you wait, the matter that makes you probably won’t end up inside a black hole. It’s one of the most pervasive ideas out there: if you wait […]