Phil Plait: How to defend Earth from asteroids

www.ted.com What's six miles wide and can end civilization in an instant? An asteroid - and there are lots of them out there. With humor and great visuals, Phil Plait enthralls the TEDxBoulder audience with all the ways asteroids can kill, and what we must do to avoid them.
TEDTalks is a daily video podcast of the best talks and performances from the TED Conference, where the world's leading thinkers and doers give the talk of their lives in 18 minutes. Featured speakers have included Al Gore on climate change, Philippe Starck on design, Jill Bolte Taylor on observing her own stroke, Nicholas Negroponte on One Laptop per Child, Jane Goodall on chimpanzees, Bill Gates on malaria and mosquitoes, Pattie Maes on the "Sixth Sense" wearable tech, and "Lost" producer JJ Abrams on the allure of mystery. TED stands for Technology, Entertainment, Design, and TEDTalks cover these topics as well as science, business, development and the arts. Closed captions and translated subtitles in a variety of languages are now available on TED.com, at www.ted.com/translate.

[@JakeBroe]

"We have a space program and we can vote. Nobody has to die."

[@AB-1023]

Severely underrated video and talk. This should have a million views. Great job, posting this to my website thank you

[@hartmanpeter]

One of the most entertaining and well put together TEDx talks I've seen. And I say that caring not even a little about asteroids and comets. Bravo!

[@Saukko31]

I love Phil's enthusiasm, and this was an interesting lecture.

[@jasonsax2]

he's a great speaker! i enjoyed this one. great timing and content. thanks!

[@Macc504]

Love this guy

[@Deader87]

Me too! Lots of energy and enthusiasm!

[@wyldeman0O7]

Phil Plait has that nerdy-swag going on. He's one of my favorite public figures of science.

[@lgrisotto]

great talk! i hope for more like this

[@martinbondesson]

Omg, Phil's got a TEDtalk now! That's awesome! I'm a huge Phil Plait fan, and have been for many, many years!

[@soulsanctuarymusic1]

MORE SPEAKERS LIKE THIS PLEASE!!

[@Trinivalts]

Good speaker, got me hooked during the 1st minute. Learned something aswell.

[@dancingelf1988]

COMPLETELY. AWESOME. Get this guy back. I want more!

[@eatingtacos000]

great video much thanks

[@RiverSiege]

This was fascinating

[@naybobdenod]

Very entertaining and also very informative.

[@jadagod]

Great talk!

[@yashaouchan]

This is great. I loved it.

[@Heavensrun]

Hey, you got Phil Plait in my TED Talks!

[@DanielVerberne]

Phil Plait is one of my favourite humans. I've never met him but would love to share his company; he's intellectually stimulating and has fantastic diction. Love his scientific outreach, he's a brilliant advocate of the value of science to our species.

[@Lundix]

@xjaskix I'm very curious about how you would handle an ailment that usually requires some form of medication. Say ... type 1 diabetes, asthma, or perhaps a little angina. Would you: A) Take the drug? B) Pray really, really hard? C) Refuse to acknowledge the ailment alltogether? Perhaps there's another alternative I've missed? Please do refrain from replying with the "it wouldn't happen" routine though, try to stick with the hypothetical case here.

[@DaMDryer]

@dunbar9finger My point: Think about how fast a comet is.Than think about exhaust velocity of your ion drive of choice.They are around the same magnitude (10-100km/s).For Tempel 1 and a 2*10³kg probe the distance between their centers of mass would be roughly 15km, leaving at least 7km of space between them. So now, we assume Tempel 1 traveling at 20km/s and the ion drive to have double the exhaust velocity. The ions would need 0,175s to reach, but the comet already moved 3,5km!

[@toonpig6345]

Real interesting talk. If you enjoyed it read his blogs very good reading

[@ksn1337]

@RareAirSupply very useful, thank you.

[@silentdoctorable]

I like this guy! I hope he speaks on TED again!

[@DaMDryer]

@DaMDryer Additionally: Comets rotate, and even if the ion hit somewhere at the edge; after said comet moved 3,5km they would speed/slow its rotation at best. In this case, most of the time, the ions would not even reach at all.

[@chessdude67]

Thumbs Way Up! This guy is great.

[@dunbar9finger]

@DaMDryer Firstly this wasn't necessarily comets. It was any sort of impact body, comet or meteor. Secondly, this entire gravity-tow proposal is based on the premise that the probe is matching velocities with the target so it can travel alongside it. In that frame of reference it is incorrect to calculate as if the meteor moves out of the way of the particles unless you're picturing a form of friction (in a vacuum?) acting on those particles after they are expelled from the probe.

[@NormanVsNorman]

Love it!

[@LeonidasGGG]

FAN-TAS-TIC! Now, THIS is TED.

[@DaRealPatMan]

This guy is a genius!! Love him!

[@dustintaber]

What a good crowd

[@jayswaggjones4239]

He said its not but it's good to research these things

[@gneisstuffwacke]

I used this talk for my comm class hmwk.

[@JohnMahony75]

Cool as always, Bad Astronomer!

[@RevyNai]

@Raazh Have you ever put a hot pyrex dish into cold water? (or the other way around works too). I mean, I'm definitely no expert on asteroids and such, but I have no problem imagining an icy body exploding when it's suddenly super heated.

[@Iregosha]

This guy is a good speaker.

[@JakeBroe]

Agreed, this should have more views than it does

[@Azimuthas]

I love this guy.

[@CooperTroopa]

quality!

[@dunbar9finger]

@DaMDryer The only way to solve the problem is the make the "exhaust" of the ion drive miss the asteroid so it doesn't push it away just as hard as the gravity of the probe is pulling it. And the only way I can think of to do that is this: Aim to push away from the asteroid at a skewed angle to the left so the exhaust misses the asteroid, fire the engine for a while like that, then rotate to a new position that aims to miss the asteroid to the right, fire for a while, repeat.)

[@justgivemethetruth]

@RevyNai Pyrex is not really the best substance to use for your example, it is a monocrystal so expands and contracts evenly and is break resistant in that cse. Regular glass would be a better analogy. They used to. maybe still do, make coffee pots out of pyrex to boil water.

[@cheddar2648]

Gravity tug: simplicity, reliability. It just requires a lot of lead time.

[@Skeluz]

Like a boss!

[@DaMDryer]

@DaMDryer ... inelastic, the ions would only erode the surface insignificantly before bouncing back into space. They would never significantly cancel out the gravitational pull of the probe.

[@zahra-bs2pz]

Phil Plait is an icon

[@karadan100]

Kind of ironic they did this at Boulder..

[@dustdust7]

The "if" in "if we detect them" if quite a big one.

[@DistinctiveBlend]

Hey it's Phil! This guy is great and he has his own channel. /user/TheBadAstronomer

[@evanformcr]

Dean Pelton from Community 10:43

[@GMLSX]

Two KZbinrs in a row? Thats something new.

[@1980albatros]

Phil has got to be the coolest science presenter ever. how else could you make a crowd laugh while discussing impending doom and ways to prevent it. }:)

[@majinspy]

@0r14n583lt Probably harder than you think. The HUGE gravity of the sun is causing these things to rotate around the sun. Therefore, it would be very hard to just right-angle their trajectory directly into the sun. We can probably push / pull it, but the idea of completely overriding the sun's force is a bit rough.

[@littlekima]

he is amazing:D

[@bizzee1]

Phil Plait gives me such a nerdgasm.

[@datlik9]

I like this guy

[@xyoop]

He is talking in such passion that I wish for asteroid to try to mess with us right now

[@Trazynn]

I always watch the intro twice.

[@dunbar9finger]

But, if the probe's ion drive is throwing mass toward the meteor to propel itself away from it, how does that mass not collide with the meteor and push it in the opposite direction thus canceling things out? The ion drive exhaust would have to "miss" the meteor and that would mean the probe isn't pulling directly away from the meteor.

[@Astrostevo]

Cheers BA, superluminous interesting talk. :-) One small thing ,, how do we know for sure that the dinosaurs didn't vote? ;-)

[@GetMeThere1]

We're here. We're self-aware and have learned a bit about ourselves and how things work. We're established. Now, the two fundamental things we have to figure out first (from a scientific AND social perspective) are how to keep our planet healthy from 1) Destructive processes generated here, 2) Big rocks from outer space whacking us. After that, it's star trekking time...

[@PotadoTomado]

Hehe, that's a good talk!

Would it be possible to catch Apophis and place it on our orbit? I mean are we capable of building probe with enough gravitational thrust so that it would be able to stop Apophis before it comes back from the sun?

[@Stringprodigy]

@leisulin "So, yeah, no need for a "facepalm"....since the "asteroid defense" you are referring to would consist, almost certainly, of simply LOOKING FOR THEM and finding out if any are going to hit us any time soon." Again, they've been doing this for years. Get with the program.

[@ScottishAtheist]

@WyldOrbit Yes, I'm sure there is.

[@ferocioustick]

My immediate reaction would be to say no, it cannot be slowed down to land on earth softly. However, I am not a cosmologist/astronomer/engineer, so I could be completely wrong. Smashing it into the moon or Mars? That seems possible, and it gives us the opportunity to examine a newly formed asteroid impact somewhere other than our own planet. Still, it would be difficult

[@lilgabagool]

haha great presentation

[@kyral210]

Deep impact :D

[@RockalilyDunne]

I like this guy :)

[@DaMDryer]

@dunbar9finger I think the likely answer to your problem is relative movement.

[@lives2live]

BTW this guy's channel is: TheBadAstronomer Check him out. I was never into astronomy before I stumbled on his channel a few days ago but now I'm pretty hooked.

[@SAsgarters]

I see the flying car commercial paid off. The quality of the last few speakers has been fairly high.

[@MrKohlenstoff]

The presentation seems a bit forced during the first half, but all in all, I'm quite impressed. :>

[@delta0307]

at least this guy isn't boring ^__^

[@caseygtr]

@St8Solja it's mass could super heat to change quickly from a solid to gas, thus rapid and violent expansion in what scientist call an 'explosion'.

[@indalecio21]

04:40 Tunchanka!

[@TheFartoholic]

@kirbienstien Of course it isn't. He's just using them to describe the strength of the impact.

[@drorjs]

this is the guy from the badastronomy blog. in case your interested insome daily astronomy news... : )

[@ammiekid]

I say we just pray, and the power of the "all mighty" will save us.

[@invinciblemode]

Is it ironic that a talk about asteroids is happening at Boulder? xD

[@dunbar9finger]

@DaMDrye A typical medium size passenger airplane goes about 400 miles per hour, which is about 54 m/s. Are you afraid that if you let go of your glass of water on an airplane it will suddenly fling backward and smash the rear wall at 54 m/s? No, because you, the glass, and the plane are all matching velocities. The comet will not move aside because the ions are matching its 20km/s sideways velocity already even before the probe emitted them.

[@OhManTFE]

Lol love this guy!!

[@SpartacusCZ]

What about giant Magnets to redirect it??

[@freesk8]

@SoEFleX NASA and voting are both relevant to this video. What bothers me is when people try to intimidate others from stating their opinion, just because they disagree with the opinion but have no rational way to oppose it.

[@DaMDryer]

@dunbar9finger Thanks, I did go astray. But hopefully not meteor, as that would mean it did hit ;) Now, this leaves meager acceleration on the bodys orbit (if it has one), for it to move out of the way. These times, ions would still not hit the centre... Time to ask whether it would be bad, if those ions hit: Opposed to gravity, the ions would only affect a significantly small portion of the bodys surface. And as their collissions with the surface would by no means be perfectly...

[@JohnBlonn]

12:23 We'd be riiiich!!

[@chasethemooseinc]

how ironic he's in boulder talking about space bolders

[@alejandroolivares6263]

Then how did all of the underground cave systems go untouched in Mexico including the giant crystal caves .how is it possible for these places survive such a impact dead on site...

[@shazampanda]

I find the fact that he's giving this talk at TEDxBoulder hilariously coincidental.

[@NitrEX4]

I dont wanna cloooose my eyes... I don't wanna faaaall asleep

[@ammiekid]

From what does any asteroid or comets come.

[@TheGodlessGuitarist]

@caseygtr sounds very plausible to me

[@YawnGod]

It's like he's speaking to a classroom of primary school children, but it's an interesting topic. I wish the talk was intended for adults, and not kids.

[@Gytax0]

@goodvibes03 You mean 2036?

[@Hollywood4Fun]

Love his delivery.... Spock. We could mine the asteroid.... we could be rich. Funny stuff. Great comedic timing.

[@RosbifFrog]

'We cant move the Earth, at least not easily' - I'd think impossible! Lol!

[@smalltownescape]

"the difference between us and the dinosaurs is that was have a space program and we can vote." finally! a definitive answer!

[@kiddhitta]

so basically what he is saying is we need to learn how to control these asteroids so we can use them as a type of weapon on other countries. i like it. i like it a lot.

[@Hythloday71]

He says that big rock Apophis that passes in 2029 has a 1 in a million chance of going through that key hole thingy, well that's fine now, but as the date looms and data is aquired, those odds will either rise or fall, by the actual date of passing, i suspect we'll know to a practical certainty by the day it passes. Kind of un-nerving, regardless of the current odds.

[@gnomechomskylives]

@batbawls I bet it was PETA: People for the Ethical Treatment of Asteroids. (Sorry I couldn't resist...:)

[@Chris.Davies]

Gravity tractor won't work. To stay away from the object, it requires far too much fuel to hold that station. This just doesn't work. Even an Ion drive isn't good enough.

[@daneimp]

We have a spaceprogram aaaand we can VOTE! :D HAHA!