Neil deGrasse Tyson

December 17, 2011

I am Neil deGrasse Tyson -- AMA

Once again, happy to answer any questions you have -- about anything.

Are you becoming addicted to Reddit?

No. But clearly others are.

Time travel.. when do we get to do this? And how do you see it coming to fruition?

Space Station Astronauts routinely travel a few thousandths of a second into our future. Beyond that, get over the fact that for the foreseeable future we remain prisoners of the present.

For people like me. Who are you?

Just someone who is in love with the universe. And as Carl Sagan said, "when you're in love, you want to tell the world".

If a space traveling entity approached you with an opportunity to visit any celestial object from any distance and allow you bring one scientific instrument of your choosing, where would you go and what would you bring? The size of the instrument does not matter, but keep in mind the farther away your object of choice is, the more it may have changed (i.e. if you hoped to visit the recently discovered supernova SN 2011fe, you would arrive 21 million years after the event).

I'd bring my iPhone, as the most compact representation of modern culture there is. And I'd visit a civilization on a galaxy 65 million light years away. Assuming I can get there instantaneously, I would look back to Earth with their presumably super telescopes and witness the extinction of the dinosaurs - the light of which is just now reach them.


Last I checked, it was plate tectonics that shaped the mountains. The rest of your statement, to may eyes, waxes more poetic than sensible.

I also just wanted to say, thank you for everything that you do, and for answering our questions. You're a huge inspiration to me.

Kepler 22-b is just the beginning. We need a whole catalog of earth like planets around sunlike stars in the goldilocks zone so that we can learn the statistics of who and what we are. Next steps, seeing if their atmospheres offer telltale signs of surface life - life as we know it, that is. Oxygen, among them.

As for terraforming - we can't predict next week's weather on Earth. The hope of terraforming another planet to our liking in the face of that fact seems among the most far-fetched concepts preoccupying the futurist.

Solar Flares 2012.. Are we screwed?

We currently enjoy an unprecedented capacity to monitor the Sun - in HiDef. So the reporting of solar flares and other surface burps is at an all time high, but in fact the Sun is as "quiet" as it's been in more than a century. So if we don't survive 2012, it will be no fault of the Sun, or any other 2012 hoaxing that pervades the internet.

Once we reach cingularity, is it probable that we will reach multiple levels of cingularity? Eg artificial intelligence creates something that can create technology better than they can?

I think too much has been made of the approaching "singularity". Apart from the fact that the movement stole or perfectly good word for the center of a black hole, the machines (originally) and the computer (recently) have surpassed human performance in countless ways. So If the day comes when a computer can solve other classes of problems, more power to it. But the idea that somehow all of life and society will be recognizably different is, to me, an overstatement.

One bit of advice/text you wish you could broadcast to the world?

"Get over yourselves"

What do you think is your most significant accomplishment in your lifetime so far?

EDIT: Wording.

Raising my children. Still a work in progress, but I'm happy with what I see thus far. whether or not they become scientists, they are no doubt scientifically literate.

You do have any words on the passing of Christopher Hitchens?

My tweet from yesterday summarizes any eulogy I would give: Gone too Soon: Christopher Hitchens 62. Tireless supporter of human rights and fighter of dogma under any guise.


A re-boot of the 1980 Cosmos series presented by Carl Sagan. A sequel befitting the 21st century in which we live. 13 episodes, as was the original. To air in the spring of 2013. On FOX. Yes, on FOX.

Is time linear?

No. All motion and all gravity distorts time. For high precision work, the full hammer of relativity needs to be invoked to get the right answers. GPS satellites, for example, invoke relativistic adjustments to their time-keeping, because of their high (and persistent) orbital speeds.

How does it feel to be as awesome as you are? Serious, you are the reason why I'm majoring in physics in college :)

That for the accolade. But I'm just sharing my love of a subject, folded with my love of life. And in my walks of life I have found that not enough people share, lest the world become a more awesome place.

Do you think we'll find the Higgs boson in 2012, given the recent news? He sounds like a tricky fellow to me.

There will be more reports that they might have found it. And at some point we will all agree that it's there. Would have been much more fun for physics if it was not there. Nothing like a failed prediction to stir the pot.

Since you're a NYC local, what's your favorite restaurant in the city?

I retain a curious fascination with the Wall Street McDonalds. It has large brass handled front doors. Has a stock ticker in full view. And there's a piano player during lunch. Apart from that, my favorite place to eat in the city is home. The great tragedy of learning to cook a dish better than what you find in a restaurant. Also, wine at home is manifold cheaper than wine in a restaurant.

Hey Neil, can you somehow try to to make it a little easier to grasp the concept of infinity. best wishes from Germany!

No. The human mind, forged on the plains of Africa in search of food, sex, and shelter, is helpless in the face of infinity.

Therein is the barrier to learning calculus for most people -- where infinities pop up often. The best you can do is simply grow accustomed to the concept. Which is not the same as understanding it.

And when you are ready, consider that some infinities are larger than others. For example, there are more fractions than there are counting numbers, yet they are both infinite. Just a thought to delay your sleep this evening.

Hello from Sweden, Neil. It is a real honour to welcome you back to Reddit again.

What do you think of the latest developments at CERN with the Higgs-Boson and what will discovery of this particle do for physics and science in general?

What type of technologies or societal impacts could its discovery lead to?

To discover something you expect to be there does almost nothing to advance physics. We're all focussed now on the misbehaved neutrinos, and any other UNEXPECTED result that may emerge from CERN, the most energetic particle accelerator in the world. FYI: One of many signs that the USA is fading: Our Super-conducting Supercollider, which was cancelled by Congress in the early 1990s, would have been 3X the energy of the current Large Hadron Collider at CERN. Now our particle physicists stand on the Atlantic shores, look across the ocean, and long for the frontier that was once theirs.

If you could move to the earth-like planet 600 light years away, would you buy a beach house or a villa?

If first try to lose some weight. if the planet has the same density as Earth, then at 2.5 x our diameter, you'd weigh 2.5 times more than your Earth weight. After that, I'd surely buy a coastal beach house. Always loved the ocean.

Do you see artificial wormholes ever being produced? Would we ever be able to sustain any 'exotic materials' necessary?

Thanks for being here! :)

Yes. But as long as our energy source is fossil fuels extracted from the ground beneath our feet, we are hopeless far from wielding the energy necessary to open a wormhole in the space-time continuum.

Do you ever wake up, look in the mirror and say, "God damn, I am Neil deGrasse Tyson"?

Ha Ha. No. But your question reminds me of the fact that in a mirror, the optics conspires so that you can only kiss yourself on the lips.

Do you believe neutrinos can exceed the speed of light?

I can accept data, if the data require it of me. But for an extraordinary result such as ultraluminal neutrinos, you must not only repeat the experiment, which they did, somebody else has to duplicate the experiment as well. Only then will the result gain acceptance. This is the way of science. A fact often neglected by journalists - especially those who chase the results of single experiments and report them as new truths.

What is the best thing you have ever eaten, and/or what is your favorite meal?

Fois Gras. On my deathbed that will be the only food I will regret not having eaten more.

Favorite meal? Several. Lobster with a side of pasta in garlic sauce, accompanied by a Les Clos Grand Cru Chablis. I also love my own pistachio-mint encrusted rack of lamb, roasted potatoes, blanched broccoli, accompanied by a vintage Pauillac. And my wife makes an awesome meatless lasagna. FYI: About 2/3 my dinners in a week are vegetarian.


Burbidge, Burbidge, Fowler, & Hoyle 1957 "The synthesis of elements in the Star" which is the first realization that we are stardust.

I am a graduate student in the humanities, and I have also have a tremendous love and respect for the hard sciences. But I find there is a lot of animosity in academia between people like me and people in physics/biology/chemistry departments. It seems to me that we are wasting a huge amount of time arguing amongst ourselves when in fact most of us share similar academic values (evidence, peer review, research, etc).

What can we do to close the gap between humanities and science departments on university campuses?

The accusations of cultural relativism in the science is a movement led by humanities academics. This should a profound absence of understanding for how (and why) science works. That may not be the entire source of tension but it's surely a part of it. Also, I long for the day when liberal arts people are embarrassed by, rather than chuckle over, statements that they were "never good at math". That being said, in my experience, people in the physical sciences are great lovers of the arts. The fact that Einstein played the violin was not an exception but an example.

And apart from all that, there will always be bickering of university support for labs, buildings, perfuming arts spaces, etc. That's just people being people.

What is your favorite quote from a scientist?

Ptolemy, in the margins of his greatest work AD 150, "Almagest" (which literately translates from the Arabic to "The Greatest"): In this book he lays out the mathematical foundations for the geocentric universe. Reflecting on the motions of the planets, not fully understanding what's going on, he penned: "When I trace at my pleasure the windings to and fro of the heavenly bodies, I no longer touch earth with my feet. I stand in the presence of Zeus himself, and take my fill of ambrosia."

What do you believe will be the biggest technical innovation within the next 20 years and why?

These are always hard to predict. Who would have thought 20 years ago that the smart phone would out-perform every handheld device ever portrayed in a science fiction story, even those taking place centuries into our future. With that caveat, I'd say machine-brain implants that connect the internet directly to our neurophysiology. That'll be fun. Perhaps then we can beat Watson on Jeopardy.

My 8th-grader's science teacher has no idea who you are. Therefore, I am concerned about her education. Should we move to another school district?

If she does not know who I am it probably means she watches very little television. A person can hardly be faulted for that. My biggest concern would not be that she didn't recognize who I am but if the ideas I share about the universe are foreign to her. Ideas should always matter more than people.

Any favourite Observatory?

LIGO: Like Don Quijote, trying to accomplish the near-impossible. These are physicists trying to detect the passage of gravity waves across earth, sent by distant colliding black holes.

If you were given free reign to affect the curriculum of schools, what would you change in science education?

I would teach how science works as much as I would teach what science knows. I would assert (given that essentially, everyone will learn to read) that science literacy is the most important kind of literacy they can take into the 21st century. I would undervalue grades based on knowing things and find ways to reward curiosity. In the end, it's the people who are curious who change the world.

Which books should be read by every single intelligent person on planet?

The Bible [to learn that it's easier to be told by others what to think and believe than it is to think for yourself]; The System of the World (Newton) [to learn that the universe is a knowable place]; On the Origin of Species (Darwin) [to learn of our kinship with all other life on Earth]; Gulliver's Travels (Swift) [to learn, among other satirical lessons, that most of the time humans are Yahoos]; The Age of Reason (Paine) [to learn how the power of rational thought is the primary source of freedom in the world]; The Wealth of Nations (Smith) [to learn that capitalism is an economy of greed, a force of nature unto itself]; The Art of War (Sun Tsu) [to learn that the act of killing fellow humans can be raised to an art]; The Prince (Machiavelli) [to learn that people not in power will do all they can to acquire it, and people in power will do all they can to keep it]. If you read all of the above works you will glean profound insight into most of what has driven the history of the western world.

What is your favorite moment with Stephan Colbert?

Was fun to be interviewed with him out of character in this event: But my favorite private moment was at his home, the day before he was flying to LA. In his library I noticed a blank space on a shelf, adjacent to a stretch of trophies and awards he's won for his comedy and journalism. I asked why that spot was blank. He said it's for the Grammy he was going to win that weekend - which he did.

Hey guys, to avoid the same questions as last time take a look at Neil's previous AMA

Thanks. So that I don't have to be the meanie.

If moving faster than the speed of light were possible, What place would you visit first?

Or what would be the first thing you did?

If moving faster than light were possible, it would also mean you could go back in time. I would go straight to the Big Bang -- and earlier. Surely the most awesomest moments in all of time

Fairfield University physics major here. My buddy and I (the only two sophomore physics majors) are coming to your lecture on campus in April!

We have a large liberal arts core curriculum (60 credits), so majoring in physics is extremely difficult schedule-wise and damn near impossible to do without knowing you want to study physics beforehand. This, and that physics scares people for some reason, explains why our department is so small.

As a science educator, any ideas on how to make studying physics more appealing?

PS: I can't wait for you to come to campus!! Any chance you'll want to meet our small physics crowd?

50% of my college education was in courses that had nothing to do with math or science. And I don't regret a moment of it. There's something to be said for when all parts of the brain fire at all times. Harvard, for example, a liberal arts school, has many more Nobel Prizes in the sciences than does MIT. Just a random fact to reflect on.

About making physics more appealing, not enough attention is given to the power it grants the student. it's typically taught as just another subject, rather than as the foundation of nearly all knowledge of the natural world. If more people knew that, perhaps they'd be flocking to the physics classes rather than shunning them.

If there was any sci-fi show you could be a regular on, which one would it be and why?

No question about that one: Big Bang Theory. The characters are playful and I can relate to every one of them, either from personal experience or from close friends and colleagues.

Do you think the commercial availability of space tourism is in the near future? I'd gladly save up my whole life to see Earth from the outside.

yes. But not as currently conceived by Branson and others. They promise orbital flight, as a natural next step from the vertical joy-rides that take you above the light-scattering molecules of Earth's atmosphere. To go up and back is VERY DIFFERENT from reaching orbit with the requisite speed of 17,000 miles per hour -- sideways. That being said, who wouldn't take such a trip. I'd surely save several years of vacation money for those 20 minutes or so. Good luck to them.

do you have a favorite planet or solar system?

Saturn in our own solar system. And You gotta love Alpha Centauri. The closest star system to our own. Not yet known if it has planets, but it's always best to meet your neighbors.

Do you use reddit outside of these AMAs?

This is my second time ever on Reddit.

I only wanted to say thank you.

: - )

what do you do in your spare time for leisure?

Broadway & Off-Broadway Theater. Fancy restaurants, half the time reflecting that I could make it better myself. Wine tastings. Reading antiquarian books on science - especially those on which our understanding of the physical universe pivoted. Playing with my kids

What are your thoughts on the recent findings that hint at the Higgs Boson's existence?

But as discoveries tend to show up when our theories are wrong, what happens if we don't find any evidence suggesting the Higgs?

No Higgs will force a re-consideration of the "Standard Model of Particle Physics". But it can force much change since the idea and concept works quite well, as is - three energy families of particles that correspond to the Quark, the photon, the electron, and the neutrino. So any new idea will more likely enclose the Standard Model than full-up replace it.

Hi, I am an astrophysicist myself. What gives you inspiration when working in this amazing field? I am young and I have a lot of momentum right now, but would like to hear some ideas of yours.

Looking up at a star-filled sky.

What is the biggest hurdle you've encountered when arguing for increased scientific funding? (i.e., in schools, in the public, etc)

EDIT - I also wanted to say that your last AMA truly blew my mind away with ideas I hadn't considered before... such as that a photon of light does not experience the passage of time since, by it's nature, it's traveling at light speed.

Many people are not prepared to understand how innovations in science, technology, engineering, and math (STEM) are fundamental to the economic health of nations. they think that scientists are just another special interest group fighting for money like everybody else. In my next book (Feb 2012) titled "Space Chronicles" I make this point at length.

Any advice to a 15-year-old black man who needs to tell his family that he does not believe in god?

You don't need to tell them anything

Apart from that fact, it is they who need advice, the day you finally tell them.

As one approaches the speed of light and the time inside a ship is much shorter than that relative to those, let's say, on earth. Now if those in the craft are going near the speed of light and the destination was 100 lightyears away, would it actually take 100 years of time for those inside the craft or is it 100 years to those on earth while those in the craft feel little effect (like a months or a few years go by). Does that make sense?

The 100 years passes on Earth. The duration of the trip for the traveler can be made arbitrarily short, just by increasing their speed relative to that of light. Then when they return 200 years later, everyone on Earth will have forgotten about them -- a hidden cost of fast space travel.

p.s. none of this has anything to do with "making sense"

How can I meet you?

Come to a public lecture. Always listed here:

Heard you for the first time on the Nerdist, now I'm an avid Star Talk podcast listener! So thank you for giving me more interesting things to listen to on my commute.

There's been a lot of buzz on SOPA lately for obvious reasons, do you have any opinions on the issue? Wouldn't it somewhat restrict the sharing of many great discoveries from reputable educational establishments?

Depends on how broadly SOPA gets invoked. If it's just to stop piracy then who but ardent hackers could argue against that. Even so, there's so much legitimate public domain content on the internet than it just might not have the devastating effect that people fear.

What awesome gifts are you giving away this Christmas?

Then it wouldn't be a surprise.

I was reading the other day about space elevators. What kind of safety procedure would be required if the elevator gets stuck in the upper levels of the atmosphere?

Send hamsters first. If the elevator where itself a hoistable mini-hotel, then who would complain about having to stay in space a few more days?

Would you be willing to purchase a trip to LEO?

Low Earth Orbit? Yes. But would rather go to the Moon or Mars.

What's your opinion on popularisers of science who, although are enthusiastic and well-qualified in the subject, dumb it down for the layman to the point where it borders falsehood?

I have unorthodox views on that subject. The exact truth of what a popularizer says is not as important as whether the program or speech or interview sparks interest within the viewer. In the end, true enlightenment must be a self-driven quest. And the details are incidental to this journey.

Are you the sexiest astrophysicist alive?

I was in the year 2000, apparently. In People magazine's sexiest man alive issue. Hard to get big-headed about it. Consider the category. And that year, Brad Pitt was the sexiest man alive, transcending category. So not only was all that 11 years (and 30 lbs) ago. The category was without precedent, and has never repeated. Which led one of my students to assert, "That means you are the Sexiest Astrophysicist there ever was, and ever will be".

So it's an innocently playful moniker that I carry, but I never volunteer it.

This infamous picture.

Discuss? With the sideburns and pythons that could strangle Hulk Hogan, the masses are curious as to what was going through the mind of a young Neil deGrasse Tyson.

If you've done an AMA before and answered this, I missed it.

If you are referring to that bootlegged photo of me from many moons ago: the time, I was still wrestling and doing a bit of dance. So I was in very good shape. My mutton chops would be gone within a year of that photo, replaced with pointy sideburns. My continuing, silent homage to the original StarTrek series. I don't remember the event for when the photo was taken, but given the glow of sweat on my skin it was probably a party and I was surely dancing.

When humans invent something, they take something that already exists and change it. Is it possible for humans to create something new? Is it possible for humans to create a fully independent machine intelligence?

Most inventions are incremental. The best are not. Consider the microwave oven. That was not an incremental advance on the traditional oven. Consider also atomic weapons. These are fundamentally different things from conventional weapons, even though their power is still measure in units of a previous technology - in that case, "tons of TNT".

A curious fact that is. Light bulbs were once measured in "Candle-power" Cars are still measured in Horse Power. Glad we don't measure rockets in car power.

Are you expecting the Mars rover Curiosity to find life, or signs of life?

Curiosity is not designed to find life. Instead it will look for biochemistry that would serve life. That being said, if a creature scurries by, or crawls up to the camera, that would not require complex chemistry experiments to confirm.

Do you ever have massive problems watching science fiction shows for gross inaccuracies or do you secretly watch every episode of Doctor Who and Star Trek with glee?

I criticize only the shows that claim accuracy and fail. The rest, I sit back and enjoy. I admit (confess) to enjoying Armageddon, where Bruce Willis saves the world from a killer asteroid. That one violated more laws of physics than any other in memory. But it's operated on very little pretense of accuracy. So I'm okay with it.

Now about that sonic screwdriver....

If you where to die and you could challenge Death to a game to avoid dying, what game would you choose? (blatantly stolen from here)


In your opinion, what is the most beautiful image we have of/from space?

How do you feel about privatizing space travel?

If you didn't have to worry about funding, government oversight, or anything, and you had an unlimited budget, what specifically would you spend your time researching?

Gotta love earth from space, on any scale. My favorite recent image is taken by Cassini in orbit around Saturn. In this image, Saturn has eclipsed the Sun. And in this view there's a four-pixel sized speck to the left of the ball, outside the ring, barely visible without a zoom. That's Earth.

What would you say to a science-minded kid in a school refusing to teach evolution? And do you have any words of advice for someone (me) strongly considering a career in science education?

Btw, you rock. Thanks for doing this.

Learn evolution on your own. There's nobody stopping you from accomplishing that. And if the absence of evolution is state sanctioned, then move from the state. Such an exodus (if you allow the term) will render the region without scientifically literate people and the local economy will collapse in this technologically competitive 21st century in which we live. My hope is that Americans usually pay attention to when they lose money. So poverty may be the force required to effect these changes.

As for a career in science education, just remember that you sparking interest and enthusiasm in a student is far more valuable than the simple imparting knowledge.

Could you please explain how time works in relation to traveling real fast? The fact that when light travels it happens instantaneously, but it in our time it takes years. I remember seeing you mention it before, but I don't completely understand it enough to be able to explain it to somebody else.

The bizarre effects of Relativity come about from three cosmic facts: The speed of light in a vacuum is always measured to be the same value by everyone, at all times, no matter your state of motion. And the laws of physics are the same everywhere. From that comes all these bizarre effects on time and space -- things you learn in the first two weeks of Intro Relativity. A favorite (classic) book I can recommend on this subject is "The ABC of Relativity" by Bertrand Russell

what would you do if you dreamt of god speaking to you? would it have any impact on yourself and your thought processes? after all, dreams come from your self!

Of course I'd find out what he had to say. But I'd be all questions: I'd see if he was deep, and more informed than the rampant science illiteracy contained in Biblical Genesis. I'd ask him where he was, and what it looked like there. I'd ask what's the ambient temperature, and if he's wearing clothes. If so, i'd then I'd ask why. I'd also comment on how crowded things must be if all (or most) of the 100-billion dead people were in heaven with him. I'd ask why he keeps trying to kill us all with disease, pestilence, and natural disasters. I'd ask why 99% of all species there ever were are now extinct -- if God works in mysterious ways, that way is mysteriously genocidal. I'd ask why, in I Kings VII he gets the wrong value for Pi -- would have been an excellent place to display knowledge of math ahead of the state of knowledge of the day. AFter all that I'm guessing he might just escape and occupy somebody else's head.

A reminder, Neil deGrasse Tyson has done an AMA before, so don't ask him any of the questions he's already answered here.

Thank you.

What has been your most frightening experience in life?

Eyewitness to 9/11. Four blocks from my dining room window. A distance closer to the base than the height of the towers themselves. The escaping lower Manhattan with my family. No need to recount it here. It's actually all on my website:

If you were the head of NASA public affairs what would you do differently to get the word out about the International Space Station. Too few know of the implications this great machine has on our present and our future.

Congress did the right thing and declared it a National Laboratory. It's now receiving proposals from the scientific community for Zero-G science to be conducted. At that level, I don't know if public engagement is necessary. Any more than you know or care about the dozen or so other National laboratories across the country.

Do you agree that we shouldn't be actively pinging or trying to communicate with other life? I think I'm talking about what Stephen Hawking mentioned.

If aliens are just like us, then they should be feared.

Why are you so handsome? ;-)

I think I'm average-looking, But persistent TV appearances force a level of grooming beyond what is normal. I was thinking if giving a semi-annual vanity report on my Facebook page (long ago reached its 5000 limit, sorry about that. And although one exists, I have no interest in maintaining the fan-page) but haven't gotten around to it yet. So the lesson here is that whatever you look like when you wake up, you can always look better.

Would you rather skateboard through the halls of the LHC, or do weightless spins and flips on the ISS?

Weightless, all the way. (But after a few doses of dramamine.)

I just listened to you on the Nerdist podcast, and I must say I love you. What got you started doing what it is you're doing? When you were a kid, did you want to be an astrophysicist or something kid-like, such as a cop or astronaut?

Thanks for asking. It's all here.

Banana Hammock.

I like the passion and fervor with which Reddit users participate in discussions. I would not have done an AMA or its equivalent in any other venue. I have several Q&A portals on my website that open and close depending on load. (They're closed right now.) Several of my colleagues assist this effort. Beyond that, I prefer to write and give talks.

If you had to describe your life, all that you've experienced, all that you've discovered, in one single sentence, what would you say?

Also, who's your scientific hero?


Newton is scientific hero. unquestionable. Just search Tyson and Newton on YouTube and you should go straight to see me waxing poetic on the man. (Unless Mike Tyson has a Newton video too, but that's unlikely.)

I can do better than a single sentence. I offer a single word: "Maybe"

What was your favorite holiday present as a kid?

As a group, brain teaser books and small puzzles. I was endlessly fascinated by them. To this day, perhaps. I spent a week straight in astrophysics graduate school, when I surely should have been studying something or another, teaching myself to solve the Rubick's cube.

Do you view sending humans back to the Moon, or sending humans to Mars as more important? Do you think the Moon base is a necessary step for the Mars trip?

All in my next book "Space Chronicles". You just have to wait until February 27, 2012. Sorry.

Is Earth your favorite planet?

I suppose if pressed to answer I'd have to agree. But after Earth, it's Saturn. See my Saturn desk lamp in this video:

Will humans ever be able to travel to another galaxy in a reasonable time (say 5 days of flight) or are we limited by speed of light forever?

Wormholes. Wormholes. Wormholes.

Do you think we may be close to probing Europa for signs of life?

It's a little beyond our technology at the moment, that's why it fell in priority among planetary scientists for what missions they want to do next. But I'd say yes, definitely in the next 20-30 years.

How long do you think it will take until we have the means to actually live somewhere else in the Universe?

Live or visit? Visit, sure. Live, perhaps never. There's no place like home.

Did you know that Antarctica is wetter and balmier than Mars, yet people are not lined up to build condos there.

What are your feelings on SOPA and the general effect of our government on the ability to share and discover information? What do you see as the solution?

Addressed above.

You, Sir; are absolutely top notch. Any plans on giving India a visit?

Never been to India - the world largest democracy. It's nonetheless on my list. Thanks for warm request.

I've got a six hour drive today, any music/podcast suggestions?

StarTalk Radio: (also in iTunes)

My favorites from the archive: Jon Stewart 1 & 2 / Physics of Superheroes 1 & 2 / Conversation with Nichelle Nichols 1 & 2 / conversation with John Hodgman / & Live at the Bell House 1 & 2


Why are the orbits of the planets almost circular instead of highly eccentric like many objects in our solar system?

Big objects formed from the original rotating gas cloud. Google the "Nebular Hypothesis" for more on this. But it also accounts for why the planets (and asteroids) all orbit the same direction and in approximately the same plane. Everything else - especially wayward comets, were likely flung into odd orbits by close encounters with Jupiter, whose gravity wreaks havoc on passersby.

I know this isn't science related but what are your thoughts on the political situation in the US? For example NDAA, SOPA, PIPA, Occupy Wallstreet, etc, etc.

Gotta be my last question. Sorry for all whose questions follow this one. Three hours is a good chunk of time for any activity.

Curious thing about protests: People are shocked when they turn violent, with police exercising force far greater than the forces they oppose. But its the very act of police violence that garners headlines. And it's those headlines that trigger change more than any other force.

People praised Mayor Bloomberg for allowing the protesters to stay on location. But it was not his authority to grant or deny. The right to protest for grievances with the government to be redressed is fundamental to what it is to be American -- a nation founded on the need to protest the abuses of government.

In a free market economy you can't dictate the salaries of what a board chooses to compensate its executives. We have all bought into the capitalist system of our nation. Outlawing the fact that some people get too much money would be like handing out speeding tickets at the Indy 500. But what one can do is draft a manifesto that offers guidelines for what is a sensible distribution of compensation in a company -- for example, setting a maximum ratio of salaries between the highest compensated person and the lowest. Companies that comply would then get listed as best for its workers. This would put social pressure on the system, in much the same way the Green Moment has put social pressure on companies to conduct business with greater respect for the environment. That may be the best hope for the 99% movement.

Bye Reddit for now. Maybe another one in February 2012. As always, keep looking up.

-Neil deGrasse Tyson tweeting @neiltyson!/neiltyson

This interview was transcribed from an "ask me anything" question and answer session with Neil deGrasse Tyson conducted on Reddit on 2011-12-17. The Reddit AMA can be found here.