Neil deGrasse Tyson Explains Heat Shields

Do heat shields actually shield you from heat? On this explainer, Neil deGrasse Tyson and Chuck Nice explain how the heat shields on spaceships work.
What are heat shields really for? We explore objects entering Earth's orbit. Do these objects always heat up when they enter our atmosphere? We talk about retrorockets versus aerobraking and how they are both used to land spacecraft in different places. How does landing on Mars differ from landing on Earth or the Moon? Discover our world in another episode of Things You Thought You Knew!
About the prints that flank Neil in this video:
"Black Swan” & "White Swan" limited edition serigraph prints by Coast Salish artist Jane Kwatleematt Marston. For more information about this artist and her work, visit Inuit Gallery of Vancouver. inuit.com/
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About StarTalk:
Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up!
#StarTalk #NeildeGrasseTyson

[@diamondedevil]

ive been watching startalk almost everyday now for a couple of months n wow ive learned so much it inspires me to be a science/astrophysics lifelong learner so ty startalk team for sharing this knowledge w us for free !!

[@wootle]

This channel has taught me more than I ever learnt during my school years. If only we were taught this way. Very few of us were lucky enough to have great STEM teachers. Thank you Dr, Tyson and Chuck Nice!

[@ashtonvaughncharles6900]

Hey look, it's everyone's favorite time of day! ☺

[@attractiveness999]

kzbin.info/www/bejne/fJaYeI2ogZKIedU

[@zvpunry1971]

When people talk about reentry heating, they always rub their hands together 5:00 and talk about friction. But what is really the source of that heat? Everybody who has used a bicycle pump knows that it becomes hot. This is the heat energy that was in a larger volume of air that got compressed to a lower volume. In a bicycle pump there is a piston that is moved through a pipe. The pipe makes sure that the air can't escape from the piston. It could work with just the piston and without the pipe, you would just have to pump many times faster then the speed of sound. When an object is moving through the air faster then the speed of sound, it is pushing the air faster then it can escape. And that is what happens on reentry. The shockwave of compressed air gets extremely hot and radiates the energy in all directions. This radiation heats up the heat shield. There is also convective heating, when that hot air comes in contact with the object and chemical reactions with the heat shield (it burns up) that contributes to the heating. But it is easier to explain it with friction and rubbing your hands together, especially when you don't have a supersonic bicycle pump. ;)

[@stevdor6146]

"it could work without the pipe but you would have to pump many times faster then the speed of sound" so you're saying you can't pump up a bicycle tire without a pipe.

[@zvpunry1971]

@@stevdor6146 nah, it was just an improvised example... there are other methods that could be used to fill the tire, like using a spoon to fill it with sugar, water and yeast. It isn't optimal, but much easier then the super sonic bike pump. ;)

[@Nghilifa]

Yup, radiative & convective heating it is! 👍🏿👏🏿

[@zvpunry1971]

@cops and govern ment are gangstalkers I know, these questions are quite challenging for some people, but fortunately there are some subtle hints that can be discovered by almost everyone just by using the own senses and own mind, even without going to space. 🤡

[@aquarius5719]

Except for Apollo missions, there is no reentry. There is entry interface EI. Reentry is when capsule bounces against atmosphere like a stone bouncing against water in a pond before sinking itself

[@teejayh07]

I love star talk , always learn something new

[@ogaduby]

i love pizza

[@adityasinha2848]

I love pizza and star talk.

[@darylingoteborg3178]

Or relearn what you thought you knew in a different way

[@vegass04]

I love them too but I can't swallow Chuck. He's simply not funny to me

[@MrDoctorBryce]

Fax

[@longlostkryptonian5797]

Gentlemen, please think about doing a whole episode of things with misleading names or that are oxymoronic,. That might be fun!

[@pulkitmohta8964]

One of the classic misnomers would be "Electric Motive Force" which never is a force at all

[@AJD...]

@@pulkitmohta8964 just like centrifugal force. Which is not real but a pseudo "force"

[@Chris-hx3om]

@@pulkitmohta8964 Incorrect. Electromotive force is the electromagnetic force, one of the 3 fundamental forces. (strong nuclear, weak nuclear and electromagnetic)

[@pulkitmohta8964]

@@Chris-hx3om nope. The EMF, despite its name, is measured in Volts. EMF is used to describe and measure the potential difference of a battery. Hence the name and its use is a misnomer.

[@pulkitmohta8964]

@@AJD... yup

[@_somerandomguyontheinternet_]

The fact that the falling guy wouldn’t be killed by burning up kinda reminds me of that saying: “It’s not the fall that kills you; it’s the sudden stop at the end.”

[@Synthwave89]

Is there a better combo in the universe than Neil Tyson and Chuck Nice talking about science and jokes?

[@patrickgomes2261]

if multiverse actually exists, there is a universe where chuck is doing what Neil does, I think thats a better combo... that would be cool

[@DaKerim58]

No

[@shonuff4323]

Yes. Anyone but NGT is a better combo. Dude is just a token intellectual

[@chancemeyers8502]

Nope. They're two hilarious peas in a pod just laughing it up and talking about our universe and the womder within

[@Bldyiii]

Pinky and the Brain.

[@torjones1701]

Aerobraking causes friction, aka: heat, which the "heat shield" prevents from entering the cabin and cooking the crew until they resemble charcoal. So, while a part of the aerobraking system somewhat akin to brake pads, it's still doing what the name says on the box. Either way, it's better than lithobraking.

[@pranay1546]

i agree but i think he is saying that the heat shield is not a necessary part to slow down, so most people think of it as a captain america's shield than a car break heating up for breaking.

[@MrT------5743]

@@pranay1546 but the heat shield is needed to shield the craft from the heat caused by aerobraking. Aerobraking does not require a heat shield since hitting air can happen on any surface. But to protect against the heat caused from hitting air, you need a heat shield. So the name exactly describes what it does, so I disagree with Neil on this one.

[@gyozakeynsianism]

It's not somewhat akin to breaks. The heat shield is a brake. That's NDT's point.

[@DaScribbler]

Exactly. Saying that a heat shield's purpose is not to protect the craft from heat is just blatantly wrong. Aerobraking will work fine without one, except that the heat isn't getting wicked away with the layers of heat shield, so things keep getting hotter until they break and melt. i.e. The purpose of a heat shield is 100% to shield from the heat of aerobraking

[@gyozakeynsianism]

@@DaScribbler It's definitely not 100% to shield the craft from the heat. The heat shield converts kinetic energy into thermal energy. The hot outer parts of the shield crumble away to expose cooler layers underneath so they can continue the work of slowing down the craft efficiently. That's NDT's whole point. He didn't emphasize the fact that it keeps the astronauts safe but that's not his point. He wants to describe how aerobreaking is a thermal process and he did that.

[@narutokunn]

7:34 when Neil NOs so passionately that his whole room NOs along with him

[@narutokunn]

@cops and govern ment are gangstalkers I read the first paragraph and I want to ask you how do you know it isn't a globe? What shape is it? Flat disc?

[@cincin0722]

I would love to hear you talk about metals cold welding in space just by touching each other

[@steve-o6413]

I never thought about that before, but I guessing it would be a lot like spot welding...

[@cedricbrouste3112]

Veritasium has a video about that, I think

[@centauria9122]

@@cedricbrouste3112 He does :) It was discovered after what happened to the Galileo space probe, and one other I think.

[@cincin0722]

@@centauria9122 so cool

[@AV8R_Surge]

I like Chuck and his smart humor. He's pretty funny. I think you two have a nice dynamic.

[@gyozakeynsianism]

It's great because not only is Chuck funny, he also represents the curious, science-hungry public so well.

[@Chuck.1715]

8:27 actually for the first rovers they have used airbags and the vehicle bounced couple of times, so sort of an inverse trampoline :-D

[@danielcockerspaniel]

You’re talking about the last stage arresting system, after 99% of the reentry energy has been dissipated by the heat shield.

[@Chuck.1715]

@@goldenstar6460 yup, those airbags were deployed afrer paraschutes.

[@anniekallen4472]

Came here for this comment.

[@akasmokey9908]

Great episode! Always take Chuck’s advice, “don’t hit the planet!”

[@rezadaneshi]

You make the most interesting discussion out of any subject

[@aaaa6824]

Great one today, this was so cool! Learnin' so much.

[@physicsisawesome4205]

Physics is incredible 'cause i'ts the king of all science and knowledge

[@OrcinusLaryngologist]

💪

[@SgtStang]

Wait til you realize that we mastered gravity control in the 50's. Oh, and zero point energy. Bye bye gas, coal... all of it🤯

[@alexanderabrashev1366]

Why not the queen? You cloud insult some butthurt people you know. We live in 2021

[@nickangelos7221]

Mathematics is the mother of Physics :)

[@abcd-gp6is]

@@alexanderabrashev1366 Because math is the queen, prince needs a princess to become king, similarly physics need lot and a lot of maths to be the king //she

[@DouglasJMark]

Excellent as always! Sorry if someone already asked this: What about the space shuttle's tiles as well as SpaceX's Starship tiles?

[@thandoreviews8886]

Though I never know what they are talking about, I always feel refreshed and hopeful after watching them. "Keep Looking Up" - wish i could always remember this.

[@amolmarathe4780]

Great. Please make a video on what all the information that can be extracted from a light source.

[@ajinkyarasal5965]

Hello Team, big fan of the show! Like literally its like a treat for the mind! Can u pls add some cool graphics related to topic that is discussed. It would be more appealing!! Thank you! Deep respect for Niel Sir!

[@christinehema4414]

HEY GUYS I'M NEW TO THE GROUP BUT I HAVE WATCHED NIEL deGrasse Tyson since I was 7 im 24 now SO thank you NIEL FROM ALL OF YOUR FOLLOWERS

[@nobodyknows3180]

17 years! You've probably seen more of Neil deGrasse Tyson than the rest of us!

[@gnotes85]

Always something fascinating!

[@lordhobo9904]

I was just thinking about heat shields. This is perfect timing!

[@erickposada6772]

Great stuff.

[@mylescarley32]

So grateful to be here so early!

[@Brenoxplayer]

Fantastic!

[@cameronbrown7231]

I would LOVE an entire episode on aerodynamics

[@bennybooboobear3940]

Me too!

[@BeDazzlePR]

Hi Neil Degrasse I would love to say I am a huge fan of Astro physics and I will be implementing every experimental possibility into my daughter life in each and every way!!!! I look forward to these videos, as I’ve been binge watching for like 2weeks now and my wife told me why do I keep laughing at the computer screen with two weirdos, I told her they are the smartest weirdos, I have ever listened too! Congrats on all your hard work and thank you for making learning fun as I’m having a blast with you and chuck! Love you guys!

[@goshidk1604]

You two are amazing.

[@ZMadtrapper]

The other lad was talking of "wicking" NOT whisking. LOVE yer vids ! WAVIN A HAND from Ontario Canada EH !!

[@cobhc1227]

this helps with the explanation for the tic taks videos

[@daanmacvictory]

I would love you to do an explainer on escape velocity.

[@daanmacvictory]

never mind, found it.. kzbin.info/www/bejne/a6jadnmchN-WasU

[@michaeldeierhoi4096]

The only thing that was hoping that NDT would elaborate on was why the heat heat shield heats up because it's not because of friction, which Chuck suggested. As the spacecraft enters the atmosphere, it is the compression of the molecules of air in front of the craft as it descends that heats up the air and hence the heat shield.

[@woodselv8230]

another great episode. Long live Tyson

[@Bryanhaproff]

Explainer Video!!!!

[@TheBillykurtz]

You guys should do one on the plank temperature and what could possibly happen beyond that temperature.

[@simateix6262]

wow how come I never knew that so cool!

[@robelw5287]

All heat shields are not ablative, take the space shuttle for example. The dark tiles on the space shuttle shild the aluminum underneath from extreme temperature without burning off.

[@OhioGentlemenArms]

I found the star talk rabbit hole and can’t get out

[@JonSnowsGhost]

Neil saying that “the heat shield worked every time” is technically incorrect. #RIP2003COLUMBIACREW

[@haze2727]

I don’t think it had to do anything with the heat shield it was because one of the wings was broken.

[@JonSnowsGhost]

@@haze2727 At launch, a piece of foam struck and damaged some of the tiles that made up the heat shield on the wing. The heat shield failed on reentry.

[@Sugondees]

​@@JonSnowsGhost Well that sums it up, it's not a heat shield issue if it became defective due to debris post launch.

[@JonSnowsGhost]

@King Pistachion yes it was. www.google.com/amp/s/www.space.com/amp/19587-columbia-shuttle-disaster-special-report.html

[@Denbub]

NDT! 👍 keeping us thinking🚀

[@photogeNK]

Nobody: Chuck in every Startalk explainer: that is so cool

[@okije]

I'm with Chuck tho, that is so cool!

[@AceSpadeThePikachu]

I'm glad Neil actually remembers 2010: The Year We Make Contact. That movie is so underrated. HOWEVER...I always took issue with HOW they portrayed the aerobrake maneuver in the movie, particularly with the "balute," A.K.A. the airbags inflating all around the ship, because correct me if I'm wrong, while that technology HAS been used to land small rovers on Mars, it was NEVER deployed during the aerobraking stage, but rather the "trampoline" stage as Chuck would put it.

[@ZeroOskul]

I love how Chuck has gotten more and more competent througout this series! Neil is great for his brain!

[@paulaguaraldi8990]

Love these two! Awesome, watch every show. WHEN are they getting back together in real life?! Not separate videos! Didn't they get the vaccine?

[@Cab00se23]

The person(s) who came up with the ablative plating need a Nobel prize

[@alrestauro]

Awesome information! Thank you. Aerobraking so cool!

[@reynoldsmathey]

Are you going to cover the upcoming Venus missions with Dr. Funkyspoon?

[@Robert_McGarry_Poems]

And other Chuck!

[@xdragon2k]

Well... technically, it is still heat shield. If it wasn't there and peel off, the atmosphere will heat up the craft that is aero braking. It's shielding the craft from the heat produced by aero braking. Hence, heat shield.

[@tonywooten596]

I agree with you, maybe we should think of it as layers of disposable shields

[@jeremybuckler6247]

I can listen to him all day

[@lghammer778]

Awesome!

[@crystalstipes9969]

Love ur intro

[@RobRoschewsk]

Thumbs up for the 2010 aerobraking shout out ... and as I was thinking of the movie being far off in the future realized 2010 was eleven years ago ..... sigh ....

[@murasaki848]

Anyone interested in understanding this sort of thing NEEDS to play Kerbal Space Program. :) 8:25 Aaaa...actually, they sorta DID do a trampoline like landing on Mars. The Pathfinder probe deployed airbags so it could bleed off the last of its speed by bouncing along the surface until it stopped. This is an example of "lithobraking", literally meaning "deceleration by rock".

[@Matt0sh]

Hey Neil can you talk about different orbits around the earth in a future episode plz?

[@tunm]

Chuck's tearing up @ 8:45

[@asquare9316]

Dr. Tyson, with all due respect, I am sure spacecraft have retrorockets to decrease the speed of the craft once it is in orbit so that they fall toward the Earth. I completely understand that retrorockets are not used to stop the spacecraft, that would take too much fuel, as you stated. However, in order for a spacecraft to come back to Earth on demand, some kind of system needs to be employed to slow the craft down from its orbital speed. Respectfully submitted by a physics teacher.

[@D3v1Nzep]

Unrelated to the topic at hand, but has been bothering me, black holes don’t allow light to escape , however, if possible, would we be able to shine enough light molecules to allow some to escape ? Essentially “overflowing the hole”? N if we could, wouldn’t that paint a better picture of what the hole actually looks like? How much light would it even take??? Love the videos really exercises my brain ! Haha

[@airheart1]

I’m not sure you can say a heat shield does aero braking.. but it doesn’t shield the aircraft from heat.. it does both. In the aero braking, heat builds on the shielding material.. and whether it wicks away through oblation or absorption and convection.. it’s still shielding the internal parts of the aircraft from the heat accumulated through the aero braking.. not sure why the first part was about how its named wrongly. It IS shielding material from heat accumulation.. I don’t understand his thought process in this explanation to say its incorrectly named 🤷🏻‍♂️

[@Loebane]

People are saying that it's friction that's causing heat, it's actually because the air is compressing beneath the capsule.

[@MrT------5743]

What causes the air to compress? Friction.

[@Loebane]

@@MrT------5743 It's not friction - the capsule is moving so fast that the air beneath it can't get out of the way fast enough and is compressed.

[@MrT------5743]

@@Loebane air molecules that can't move past each other are colliding and friction is also a factor. I'm not saying it is only friction, but it is a factor. Compression heating is also partly due to friction. More molecules in the same space equals more friction.

[@Loebane]

@@MrT------5743 Right - friction is a factor, but it's a much smaller one than the adiabatic heating.

[@Loebane]

@cops and govern ment are gangstalkers I only read the first sentence and knew the rest wasn't worth reading.

[@emanuelag0587]

How the energy gets transfered made me think that is how parkour works, they redirect the energy of their speed into new movements instead of their joints absorbing it. Maybe you should do a sports edition about how parkour is about utilizing speed into new movements

[@yashkrgupta2122012]

Enternal dimension

[@lordnomik]

The coolest airbreak example was in the "Interstellar" movie, while they were landing on the Water Planet. Circular landing to save fuel, dicrease spead and only at the last few hundred meters he hits the reverse rockets and airbreaks. And there you go ... not graceful but efficient!

[@TheCyphersys]

Hi Mr Tyson. Does this principle apply to the materials used on the blackbird?

[@fromnorway643]

More or less. Parts of the Blackbird's exterior could be heated to more than 300°C when flying at about Mach 3. That's why its hull was mostly made of titanium that maintains its strength at high temperatures better than most other materials. The Concorde, which was mostly made of aluminium, had to slow down if the temperature at the tip of its nose exceeded 127°C and was therefore limited to a top speed of about Mach 2 or slightly more, just like most modern fighters.

[@SpaldingFraser]

Love the tv show Chuck

[@_TheDeanMachine]

There was video a few years back about a guy going up in space in an air balloon and free falling back down to Earth, reminds of what they were talking about

[@danielcockerspaniel]

The parachute guy was going 1/20 of the speed of a reentry vehicle. So 1/400 the kinetic energy. Not comparable.

[@asquare9316]

Just to clarify, that guy was the second guy to do that successfully. the first guy was an AF test pilot (Joe Kittinger) who first did it in late 1950's. His jumps were done to see if the pressurized suits developed for going into space would work. Red Bull hired him to help out the second guy (Felix). Felix knew that the suit would work, Joe didn't. He also was a fighter pilot during the Vietnam War and shot down a MiG-21.

[@youtubverse]

The 100, Lost in space, Travelers, Another Life, Salvation, Dark,Zoo, snow piercer, - Next time watch n mention from these series

[@christinehema4414]

Will you be coming to NZ

[@musab02]

I somehow remember listening to the explainer earlier this week. Huh🤔🤔

[@ozgurkaratas6450]

What about the ceramic composite under the space shuttle? Afaik it does not peel off, it is a shield against high temperature.

[@lawyeroutlaw]

Why Columbia was different, and burned up... So this is actually very interesting and personally important to me as my father's company was really against decisions made in both the Challenger and Columbia disasters. And in both cases they were overruled or ignored. For the space shuttle, the process of defending the craft from this heat energy was *not* the same as was used in previous reentry vehicles (Apollo, Mercury, Orion, Gemini, etc.) That is more like what Neil is describing here, where layers of plastic are baked away and energy is transferred via convection. The space shuttle did not use that system. The space shuttle instead relied on absorbing the heat with ceramic tiles and getting rid of the heat via radiation (not convection) and so the whole bottom of the craft was armored in a bunch of absorbent, insulating tiles. This was especially vulnerable at the leading edges (wings, nose, etc) so they added a very absorbent material shielding that is basically super carbon graphite composite (called by RCC) to protect these vulnerable places. In 2003, the failure of the RCC protecting the wing at panel 8 caused a hole in the protective RCC panel, which caused the thermal protection system ("heat shield") to catastrophically fail because the heat was able to bypass the shield through that hole and destroy the less protected part of the shuttle and the structural integrity was destroyed. So they are different. But technically the "onion" way (convection via plastic resin layers) has never failed, but the reusable absorb/radiate ceramic composite tile system used by the space shuttle did fail for Columbia.

[@steve-o6413]

I remember hearing about that didn't they also loose tiles because of a problem with the adhesive process. Too many tiles lost over a critical area...

[@nobodyknows3180]

@@steve-o6413 Debris which came loose from the insulation on the large disposable fuel tank came loose and fell, impacting the wing of the shuttle upon liftoff, and this apparently was enough to knock several of the heat tiles from the critical leading edge of the shuttle wing, and while this did not affect the shuttle's entry into orbit, it had catastrophic consequences on re-entry.

[@DC2022]

​@@nobodyknows3180 yup, there was a freaking hole in left wing the carbon-carbon leading edge shield. So all the heat, all the pressure came inside the frame and started to ruin everything until the temperature rose at a point aluminium and steel were closer to marshmallown than anything (1600°C/2800F°) and then, comboed with the loss of hydraulic (so no more maneuvering options), the shuttle started to tumble and you don't want to do that at 14,000mph especially with one wing who is as solid as wet noodle and the entire craft who is more or less an empty plastic bottle. Columbia shattered into bug chunks who disintegrated during the descent.

[@lawyeroutlaw]

@cops and govern ment are gangstalkers are you asking me? Because that's a really weird thing to ask me.

[@bruceneeley1724]

So if an individual during a space walk (untethered ) was able to use some form of retro propulsion to slow their speed would they be able to parachute (skydive) safely down to the earth's surface?

[@ozgurkaratas6450]

I've thought about that a lot...I guess they would provided that they could be able slow down to parachuting speed before entering thick layers plus maintaining life support, O2 etc.

[@patlalla148]

Could heat shields explain the TIC TAC UFO video. Could it look like a Tic Tac because maybe our distance from our sun was too hot for the Tic Tac animal or UFO object thing. Maybe like when we put things in the freezer and they turn white and some things when super heated turn sort of white ( like the tic tac).

[@brandonsprague3927]

Neil what are yours thoughts on the elephants foot. Could we mine it and use its energy ?

[@Chemy.]

I knew the info but amazing to watch the show anyways

[@danuttall]

If you do your aerobraking properly, you can land exactly where you want to and then do what you need to. The main alternative is lithobraking, which can be very effective at slowing down the spacecraft, tends to not leave the craft in an operational state. Aquabraking gives a little more room for recovery, it can also leave the spacecraft in a non-operation state if not done *exactly* correctly.

[@paulhunter7002]

You're mostly right Neil. There is a general misunderstanding when it comes to accounting for the heat of re-entry. When a spacecraft re-enters earths atmosphere at orbital speed, friction with the atmosphere only provides a small amount of the heat experienced during re-entry. Most of the heat comes from the compression of the atmosphere in front of the spacecraft in the direction of travel (which is normally the heat shield side) If your remember Boyles law the more you compress a gas the hotter it gets.

[@sclabhailordofnoplot2430]

I love Boyle I didn't know she wrote a law. LOL kzbin.info/www/bejne/mpa1d2yleseFqdE&ab_channel=Britain%27sGotTalent

[@edpotter1491]

Fantastic. I think I knew this. There was a discussion of the ablative aerogel tiles falling off the surface of the shuttle years ago and the reason that was a cause for concern. Still, I did think of it as 'shielding' rather than part of the braking system. Nice, you are a funny guy! Things are getting back to normal. Doc, when are we going to hear about the symmetrical line or arc of galaxies more than 3 billion light years across? Yeah! Someone is playing with the universe!!

[@c.youngberg9511]

4:30 Neil was sooo thrown off for a sec that Chuck just outright casually said a right answer that NDT didn't see coming... that had me crackin up!!

[@nephiilim]

Uncle Neil was Born for science communication man.

[@MayoFilms83]

He said he wanted to know everything about science when he was born.

[@Prody8159]

These two are freakin cool 😂

[@jaydawg7820]

If you saw the movie 2010... the Leonoff used Giant Balloons for Airow breaking

[@buhjr4309]

It's Neil and Chuck once again

[@lisear2926]

I knew the answer wasn't going to be as easy as "something that stops phasers from hitting the ship" but I had hopes for that answer too Chunk 😁

[@vasm1807]

What about the titles being tested in spaceship?

[@jvijayid]

Surprised to learn this! Then how are asteroids getting burned in our atmosphere?

[@Lanhoj]

*That needs to be a GIF...* @7:35

[@cynodont7391]

I remember reading somewhere that some Russian spacecrafts (or was it Chinese?) used to have a heat shield made of wood.

[@giskard000]

Not trampoline, but pogo sticks! I’ll collect my Nobel now, thanks. ;-)

[@MayoFilms83]

What does Neil think of the supernova of the shoulder on orions belt?

[@oswith972]

I guess the trampoline idea isn't completely ridiculous, since NASA kind of did that with Spirit and Opportunity. They just basically had the rovers inside big inflated balloons and they just let them fall to the ground once the speed was low enough and they bounced around a few times being cushioned by the balloons

[@peridotrideaux]

1# podcasts i got to

[@dumaskhan]

to think the greatest science lessons would end up not coming from the class room, but from the internet.

[@fixedguitar47]

I used aero breaking around Jupiter, what a ride!

[@KiranR2612]

I was thinking of this idea to land.. Just a thought. Maybe someone could tell if it's a feasible approach? How about we have a landing pad with a big cylindrical structure that generates a magnetic field. And we can point the falling/incoming spacecraft towards this cylindrical target and let the magnetic field slow down the spacecraft to a soft landing? We could adjust the strength of this magnetic field according to the velocity of the spacecraft.

[@bigdiglett3258]

That would have to be a really big and really expensive device, also the g forces would probably be insane

[@RajeshKumar-ob9zy]

Its a scary Air Braking... also resulted in loss of lives. Also, What about the weight added to spacecraft due to these Heat Shields tiles? If the spacecraft contains engines, will it not be better to carry fuel instead of heat shields to slow down the craft? (off course, it would have been considered and rejected... plz cover topic in full)

[@M4nusky]

So the aero-not-a-heat-shield-brakes ramove the speed energy from the spacecraft, and that energy first came from the rocket that launched them into orbit

[@mtliedke]

I am a great fan and I love your videos. With this one however I'm not so sure. Firstly if spacecraft wouldnt have heatshield it would still slow down upon contact with atmosphere. It would surely melt and exploded before coming near the earth but it would slow down. And thats because of friction. Friction generates heat hence need of heat shield. Look at spacex starship. They make them of stainless steel because they can withstand greater temperatures so no need for so much heatshield. And the one they use dont peel off like vegetable. Its aerodynamic drag that is slowing craft down. Space shuttle didnt need heatshield to slow down. The design of the nose was a dome for that reason. So it would introduce more resistance what in fact threw the air away from fuseloge. And heatshield again, was there to take excess heat away. Not to slow vehicle down.

[@erniemorales4416]

Why have we lost BIDDING YOU TO keep looking up at the sign off of each video? I really like that, anyone else?