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Ethan Siegel
Works at NASA's The Space Place
Attended University of Florida College of Liberal Arts and Sciences
Lived in Bronx, New York
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Ethan Siegel

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Did you miss me live on TV tonight, talking about the new Earth-like planet with the potential for liquid water and maybe life on it?

Reach for the stars and catch the best 5 minutes of science on TV this week!
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Beam me up.
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Ethan Siegel

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Want to know about the most Earth-like exoplanet ever discovered? Watch me on KGW's The Square Live @ 7PM (PDT) tonight!
Here's where you can peek behind the scenes of Live @ 7.
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Ethan Siegel

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"N is for Nebula, what forms when stars die,
this recycled fuel makes cosmic apple pie."

From A for Aurora to Z for Zenith, it's the alphabet as you've never seen it before!
Every letter holds a special story for those who marvel at the Universe.
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"There are some album covers that probably stick in your mind as the “most iconic” when you think about them. Maybe it’s the Beatles’ Abbey Road album, Nirvana’s Nevermind album, or Springsteen’s Born in the U.S.A.

What Harvezt has done is imagine what these covers might look like when viewed from behind, and the result is not only visually arresting, it adds a new layer of depth to the album itself!"

We all have our favorite album covers. What would they look like from behind? An amazing reimagined art project.
From the Beatles to Nirvana, this artist’s imaginings make the originals even better!
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Very good! I particularly like Springsteen's quote ~
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Ethan Siegel

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"We read a paper — published in a prestigious education research journal — decrying the abominable state of literacy in America, which noted that 50% of all seven-year-olds were reading at a below average level.

Think about that for a moment.

Yes, 50% were below average. And — although the paper didn’t say one way or another — my assumption is that 50% were above average, as well. Because in almost all samples like this (as a consequence of the central limit theorem), that’s kind of the definition of average. In other words, there was no education or literacy crisis, at least, not based on the actual information that was being used to argue that point."

For the TL;DR crowd: the answer is "maybe not!"
As teachers begin using new and questionable methods, will students suffer and get left behind?
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+Ólafur Jens Sigurðsson Iceland did pretty good last PISA round, MATH 493, READING 483, SCIENCE 478 (OECD ave 494, 496, 501 respectively).  Canada did allright, although there's a downward trend that's concerning (or should be).  
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Have him in circles
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Ethan Siegel

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"4.) Quantum Gravity. The Standard Model makes no effort nor any claims to incorporate the gravitational force/interaction into it. But our current best theory of gravity — General Relativity — makes no sense at extremely large gravitational field or extremely small distances; the singularities it gives us are indicative of physics breaking down. In order to explain what goes on there, it will require a more complete, or quantum, theory of gravity. You might’ve thought, “well, the other three forces are quantized, but maybe gravity doesn’t have to be,” and that would’ve been a reasonable assumption, except for one thing.

The recently released BICEP2 results — assuming the B-mode polarization it detected did, in fact, come from inflation — could not have been generated by primordial gravitational waves unless gravity was a quantum theory! (If you want to have quantum fluctuations stretched across the Universe, your field — in this case, gravitational — needs to be a quantum one.)"

Go read all 5 reasons that we know the Standard Model can't be all there is!
The Standard Model can’t be all there is. Here are five compelling reasons why.
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Ethan Siegel

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"[N]ot only is helium-4 lighter than two protons and two neutrons individually, it’s lighter than four individual protons! It isn’t by all that much — just 0.7% — but with enough reactions, it adds up quickly. In our Sun, for example, somewhere around a whopping 4 × 10^38 protons fuse into helium-4 every second in our Sun; that’s how many it takes to account for the Sun’s energy output.

But it’s not like you can just turn four protons into helium-4; in point of fact, you never get more than two particles colliding at the same time. So how, then, do you build up to helium-4? It might not proceed how you expect!"

All hail the diproton! (The WHAT? No, seriously!)
You never would’ve guessed that nuclear physics could be this easy.
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Its always good till they go stealth mode need info red or a fire would be better, major led lights, im fits toooo....
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"In 1779, there was a comet right in this very region of the sky, and Charles Messier could have found this nebula; he observed it before anyone else. In fact, you may remember that the original purpose of the Messier catalogue was to help skygazers avoid confusing these fixed, deep-sky objects with potential comets, yet that’s exactly what Messier did here! He mistook M61 for a comet, and instead credit for this object’s discovery goes to Barnabus Oriani, who beat Messier to the punch by a mere six days. But 235 years later, it still appears, all but unchanged from how Messier viewed it."

Ever hunt for a deep-sky galaxy near a full Moon? During tonight's total lunar eclipse you can! #MessierMonday
Washed out by the full Moon on any other night, the lunar eclipse makes this one visible tonight!
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Ethan Siegel

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"But when it comes to energy, a factor of 1000 is huge. At energies 1000 times greater than room temperature, it is impossible for electrons to stay bound to atomic nuclei, but at room temperature, the odds of an atom becoming ionized from the 300 K thermal radiation is practically zero. Similarly, at energies 1000 times lower than room temperature, helium loses all viscosity, and becomes a superfluid.

The odds of this happening at room temperature, of course, are also practically zero. Energy effects are exponentially suppressed, so when you have a factor of 1000 difference, your odds of having the thing-you-want happen are suppressed by somewhere around e^(-1000), which is about 1-in-10^430. It’s not impossible, but I think we can safely say it’s very effectively suppressed."

Plus one for all the language nitpickers out there.
“It is dangerous to be right in matters on which the established authorities are wrong.” -Voltaire It’s been another great week over on the main Starts With A Bang blog, where we got to touch on a number of remarkable topics, including: Why are we made of matter? (For Ask Ethan #31) Trompe-l’œil Art (For our Weekend Diversion)…
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Ethan Siegel

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"But remember that all the stars that formed made up just 10% of the mass of the initial molecular clouds that birthed them, and then half of those stellar masses were returned again to the interstellar medium. Given that 95% of all the mass that initially formed these stars was eventually returned to the interstellar medium as burnable fuel, we’ll still have stars lighting our night sky for trillions upon trillions of years, and the atoms from our Solar System will be a part of innumerable future generations of them."

All stars dies, but does every star really live? The lives-and-deaths of Sun-like stars, a perfect #tbt.
From how they’re born to how they live to the end of their life cycle, this story is common to them all.
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Reading this made me feel so ignorant of all there is. I really enjoyed the article.
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Have him in circles
44,799 people
Theoretical Astrophysicist / Writer / Educator
  • NASA's The Space Place
    Columnist, 2013 - present
  • Trap!t
    Head Editor: Science/Health, 2011 - present
  • Starts With A Bang!
    Science Writer, 2008 - present
  • Lewis & Clark College
    Visiting Assistant Professor of Physics, 2009 - 2011
  • University of Portland
    Professor/Lab Coordinator, 2008 - 2009
  • Steward Observatory/University of Arizona
    Postdoctoral Research Associate, 2007 - 2008
  • University of Wisconsin
    Faculty Assistant, 2006 - 2007
  • University of Florida
    Teaching/Research Assistant, Fellow, 2001 - 2006
  • King/Drew Medical Magnet High School
    Teacher, 2000 - 2001
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Bronx, New York - Yonkers, New York - Evanston, Illinois - Torrance, California - Gainesville, Florida - Madison, Wisconsin - Tucson, Arizona - Portland, Oregon - Houston, Texas - Rome, Italy
Contributor to
Science writer, professor and theoretical astrophysicist
Theoretical Astrophysicist, Science Writer and Communicator, expert in (some aspects of) dark matter and dark energy, physical cosmology, and sometimes professor, teacher and educator.

Creator and writer of Starts With A Bang!, the 2010 Physics Blog of the Year! Author of over 1,000 articles, featured in Esquire, the St. Petersburg Times,'s Page 2, and many others.

Competitive beardsman and amateur acrobat / halloween-costumer extraordinaire.
  • University of Florida College of Liberal Arts and Sciences
    Physics, 2001 - 2006
  • Northwestern University
    Physics, Classics, Integrated Science Program, 1996 - 2000
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