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Ethan Siegel
43,989 followers -
Science writer, professor and theoretical astrophysicist
Science writer, professor and theoretical astrophysicist

43,989 followers
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“NASA’s Office of Education, in its current incarnation, oversees and administers around sixty different programs that benefit educators, K-12 students, as well as undergraduate, graduate and postdoctoral students and researchers. With the Trump administration officially announcing their budget for the next fiscal year, they provide only $37 million for NASA’s Education Office, with one major stipulation: the office must be eliminated entirely.”

So, here we are, encountering one another on the internet. There’s a really good chance that this is because you have some interest in space, science, astronomy, astrophysics, or some related area. Although I am an astrophysicist with a Ph,D. in theoretical physics, my focus over the past decade or so has been on education and public outreach: science communication. There’s an incredible Universe out there that we’re exploring, and the more we learn about it, the more effort we need to put into education and outreach if we want a society that’s with us on the cutting edge. That understands where we are and what we’re doing; that creates valuable opportunities for the next generation of scientists to participate and contribute to the enterprise of science.

So why, then, would we be okay with just eliminating NASA’s Office of Education? If we care about America, we won’t be. Read on.

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“Just four months later, under the right wind conditions, the bridge was driven at its resonant frequency, causing it to oscillate and twist uncontrollably. After undulating for over an hour, the middle section collapsed, and the bridge was destroyed. It was a testimony to the power of resonance, and has been used as a classic example in physics and engineering classes across the country ever since. Unfortunately, the story is a complete myth.”

If you’ve only ever seen one bridge collapse ever, it was probably the Tacoma Narrows Bridge. On November 7th, 1940, high, sustained winds sent the bridge from an up-and-down undulation into a twisting, rocking pattern that led to the eventual collapse of the structure. It’s been used as a classic example of resonance at work, similar to how a wine glass will shatter when exposed to the right frequency pitch. While the shattering of glass is due to resonance, and it is a real phenomenon, the numbers just don’t add up for the bridge. Instead, it’s a much more intricate phenomenon that caused that infamous bridge collapse, known as flutter. If you’ve heard the resonance explanation, you’re not alone: it’s probably the most common misconception in all of physics and engineering!

Don’t be fooled any longer. Come get the full – and correct – story today!

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“By 1961, Thorp and Shannon had built and tested the world’s first wearable computer: it was merely the size of a cigarette pack and able to fit into the bottom of a specially-designed shoe. Toe switches would activate the computer once the wheel and ball were set into motion, collecting timing data for both. Once the computer calculated the most likely result, it would transmit that value as musical tones to a tiny speaker lodged in an earpiece. The wires were camouflaged as much as possible.”

Did you know the world’s first wearable computer was built all the way back in the 1960s, was worn on your feet… and was used to help gamblers cheat at roulette? Physicists and mathematicians work with probability and predicting the behavior of a given system a lot, and when you combine that with the science of simple motion (as on a roulette wheel), the possibility of ‘beating the odds’ suddenly becomes real. Security measures that seem commonplace today in casinos, such as roulette wheels with no observable defects, a ban on computers and ‘table talk,’ and the inability to place late bets, all came about because of how scientist/gamblers have successfully beaten the house in the past.

From the 1940s up to the modern day, come hear the story of how simple physics helped defeat the casinos, and how the saga, for a few people, is still ongoing today!

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“Perhaps, as many suggested, this was evidence of an alien megastructure being constructed? But another astrophysical scenario could explain it: a recently devoured planet. Gases would dim the star overall, while outbursts and flares create irregular flux dips.”

Earlier this decade, the Kepler mission became the most successful planet-finding endeavor of all time, turning up thousands of new worlds by measuring the transit data of some 150,000 stars. When planets passed in front of their parent star, they blocked a tiny fraction of their light, leaving behind an imprint of a periodic dimming signal. But one star dims differently from all the others. KIC 8462852, known as Tabby’s star, has irregular dips of up to 20% in brightness, equivalent to ten times the effect of all the Solar System’s planets combined. What could be causing this? While a few astronomers have proposed alien megastructures, another, simpler explanation might explain it all: a recently devoured planet.

As a new dimming event is underway, astronomers hope to collect enough quality observations to validate or disfavor all the ideas bouncing around. Find out more today!

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"The success rate for landing on Mars in general is still appallingly low, and the ESA, JAXA and the RSA have never yet had one successful lander between them all. But sometimes, you put a new system in place and it works brilliantly, as it did with Curiosity. I would accept your recommendation to not “count on” the ExoMars Rover, just as I’d remind everyone that space exploration of all types will always carry a risk of failure. I think this applies to crewed spaceflight as well, and while it might be a good soundbite to say, “failure is not an option,” it’s always a risk. One well worth taking, IMO."

No words ever spoken have been more damaging to our investment as a planet in human, crewed exploration than, "Failure is not an option." If we can't accept that we might fail, we have no right to spend out time and energy trying. After all, landers, rovers and orbiters fail; when they do, we learn the lessons and try again.

Well, we've covered a lot this week: artificial intelligence, supernovae, galactic mergers, the big crunch, and exploration of the Solar System, among others. Do you like getting a dose of bonus science, and considering perspectives other than your own? Well, then, you won't want to miss this edition of our comments of the week!

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“What happens when a black hole has lost enough energy due to hawking radiation that its energy density no longer supports a singularity with an event horizon? Put another way, what happens when a black hole ceases to be a black hole due to hawking radiation?”

One of the most puzzling things about Black Holes is that if you wait around long enough, they’ll evaporate completely. The curved spacetime outside of the event horizon still undergoes quantum effects, and when you combine General Relativity and quantum field theory in exactly that fashion, you get a blackbody spectrum of thermal radiation out. Given enough time, a black hole will decay away completely. But what will that entail? Will an event horizon cease to exist, exposing a former black hole’s core? Will it persist right until the final moment, indicative of a true singularity? And how hot and energetic will that final evaporative state be?

Incredibly, even without a quantum theory of gravity, we can predict the answers! Find out on this week’s Ask Ethan.

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“Interestingly, this could also lead to a renewed interest in the search for glueballs, which would be the first ever direct evidence of a bound state of gluons in nature! If the exotic QCD predictions of tetraquarks and pentaquarks are borne out in our Universe, it stands to reason that glueballs should be there as well. Perhaps the existence of these composite particles will be verified at the LHC as well, with incredible implications for how our Universe works either way.”

Nuclear physics has, for decades now, been regarded less as a window into fundamental physics and more of a derived science. As we’ve discovered that nuclei, baryons, and mesons are all composite particles made out of quarks, antiquarks, and gluons, though, we’ve realized that there are other possible combinations that nature allows, that should exist. In recent years, we’ve discovered tetraquark and pentaquark states of quarks and antiquarks, and yet there should be even more. QCD, our theory of the strong interactions, predicts that a set of exotic states of bound gluons – known as a glueball – should exist. Finding them, or proving that they don’t exist, might be a way to crack open the Standard Model in an entirely new way.

Nuclear physics might, after all these years, hold the key to going beyond the current limitations of physics.

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“It’s a great way to spend a great deal of money, advancing science and humanity in no appreciable way. Instead, why not learn the lessons from humanity’s greatest successes? Don’t look at the technology you’ve already developed and ask, “what can we do with it?” Look at the goal you want to achieve and ask, “what will it take to accomplish this?"”

It’s been more than 40 years since humans last set foot on the Moon. The final space shuttle flight occurred six years ago already, and the International Space Station is set to reach the end of its life a few years from now. At the 33rd Space Symposium last month, NASA announced their new, bold plan for crewed spaceflight: a crewed space station that orbits the Moon. While this has the cost advantages of utilizing systems that have already been designed and, in some cases, built, it represents a failure of imagination, vision, and scientific goals. As a result, we’ll be no closer to returning to the Moon, exploring Mars, capturing an asteroid, or any other actual goal we may have.

If we want to accomplish something great, it’s up to us to at least attempt it. We need NASA to share that same vision!

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“Cosmic fireworks like these don’t truly happen at random; they are clustered in time and space around the most massive, intense star-forming regions of all. You can’t have a bigger star-forming region than one that includes the entire galaxy, and the sweeping, grand, irregular arms of the Fireworks galaxy are as good as they come. Based on what we see, we expect this elevated rate to continue for more than a million years.”

Every once in a while, a new light appears somewhere in the night sky: the result of a massive star reaching the end of its life. From many millions of light years away, the brilliance of a supernova shines across the cosmos. Just a few days ago, a new light was discovered in a galaxy only 22 million light years away, making it the closest supernova discovered in three years. The galaxy housing it is a hotbed of supernova formation, having been home to ten such explosions in the past 100 years: more than we’ve found in any other galaxy. The reason? This entire galaxy, despite having only half the stars of the Milky Way, is a giant star-forming region. Starburst galaxies like this are the best place to look for cataclysmic events like this, and NGC 6946 is maybe the best example of all.

Come see the night sky’s newest, closest supernova, and learn how to see it for yourself!

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“But there’s a fun, important, and underappreciated consequence of Bayes’ theorem that can tell us something vital about any of these steps: the odds of any one of them happening, no matter how small, could not have been infinitesimal. If you want to create our Universe with our laws of physics, our local group, our Sun, our Earth, and every one of us, given all the conditions that existed before the Big Bang, that probability may be very, very small, but it can’t be infinitely small. If it were, our model for the conditions that existed before the Big Bang could be ruled out immediately, with no need to gather data or make measurements.”

There are a great many events that occurred to give rise to the world, the Universe, and you. Everything from the Big Bang to the existence of the laws of physics to the cosmic history that created Earth to the biological history that gave rise to the 7+ billion of us today needed to unfold exactly as it did in order for things to be the way they are today. It’s an exceedingly unlikely story, and yet the fact that we’re here is evidence that it happened exactly in this fashion. But no matter how unlikely it appears, we can be 100% certain that our arrival at this point in time with these exact conditions wasn’t infinitely unlikely. In fact, it’s an inescapable consequence of Bayes’ theorem that the existence of things as they are today implies it had a finite, not infinitesimal, probability of turning out this way.

No matter how unlikely every event may have been in the past, the odds weren’t infinitely small. Find out how we know today!
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