Ethan Siegel

Ethan Siegel

A theoretical astrophysicist and science writer, host of popular podcast “Starts with a Bang!”

Ethan Siegel 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.

parallel universe
The Universe's history, from cosmic inflation to the Big Bang to the present, is known. But whether it's infinite or not is still a mystery.
universe temperature
Although the Big Bang occurred at an instant in time long ago, we still see the light from it. Will the evidence ever disappear completely?
Known as hypervelocity stars, we originally thought just one would be ejected every 100,000 years. The real number is much greater.
A computer-generated image of a bright celestial object with an accretion disk, possibly representing what the sun looked like when it was born.
Newborn stars are surrounded only by a featureless disk. Debris disks persist for hundreds of millions of years. So when do planets form?
In December 1968, human beings made their first-ever journey to the Moon aboard Apollo 8. Their most important discovery? Planet Earth.
An image of a blue and white planet in space with starry background and a bright star on the right.
Out beyond Neptune are some fascinating bodies left over from our Solar System's formation. Could one of them truly be spectacular?
fusion power
From forming bound states to normal scattering, many possibilities abound for matter-antimatter interactions. So why do they annihilate?
SARS-CoV-2 first emerged in humans in 2019. Despite much noise generated by lab leak proponents, the evidence indicates a natural origin.
A composite image shows the sun's path in the sky at different times of the year over a grassy landscape, with three arches of sun positions represented by dots, illustrating the earliest solstice.
On June 20, 2024, the summer solstice occurs at its earliest moment since 1796: when George Washington was President of the USA. Here's why.
Two breathtaking pictures of a galaxy and a star taken by the Hubble telescope, highlighting the beauty and cosmic magnitude that fuels the Hubble tension.
There are two different ways to measure the expansion rate of the Universe, and they don't agree. And no, new measurements don't help.
A new all-time record! JWST's discovery of JADES-GS-z14-0 pushes the earliest galaxy ever seen to just 290 million years after the Big Bang.
Abstract representation of a cosmic event with a burst of particles emanating from a central point, blending astrophysical imagery with geometric designs.
If you bring too much mass or energy together in one location, you'll inevitably create a black hole. So why didn't the Big Bang become one?
A deep space image showing numerous galaxies of different shapes and sizes scattered across a dark background, with many stars and cosmic objects, including the ancient Methuselah star, also visible throughout.
The Universe is precisely dated at 13.8 billion years old, but astronomers claim the Methuselah star is 14.5 billion years old. What gives?
proton internal structure
It's 2024, and we still only know of the fundamental particles of the Standard Model: nothing more. But these 8 unanswered questions remain.
standard model color
Predicted way back in the 1960s, the discovery of the Higgs boson in 2012 completed the Standard Model. Here's why it remains fascinating.
Stellar explosion
The expanding Universe, in many ways, is the ultimate out-of-equilibrium system. After enough time passes, will we eventually get there?
A diagram of the solar system illustrates the heliosphere, detailing the termination shock, heliopause, and bow shock, along with the paths of Pioneer 10, Pioneer 11, Voyager 1, and Voyager 2. This visual representation underscores key aspects of fundamental science in our cosmic neighborhood.
Some think the reason fundamental scientific revolutions are so rare is because of groupthink. It's not; it's hard to mess with success.
big crunch
For nearly 25 years, we thought we knew how the Universe would end. Now, new measurements point to a profoundly different conclusion.
LHC insides
CERN's Large Hadron Collider is the most powerful particle accelerator ever. To go even further, we'll have to overcome something big.
planetary nebulae infrared spitzer
In ~7 billion years, our Sun will run out of fuel and die. So will every star, eventually. Here are the different fates they'll encounter.