Neil deGrasse Tyson Explains "What Goes Up, Must Come Down" 

"What doesn't reach escape velocity, Must come down"

I love it when Chuck makes a discovery that was just explained by Neil.

Chuck’s a great partner to have on these. Wonderful Comedic timing.

Chuck makes Neil’s information sound less like a lecture and more like a friendly conversation between friends! I happen to like the conversation! Thank you guys!

I would like a T-shirt that says, “what goes up at 6.9 miles per second must come down”

This refers to my confidence when I see Neil it goes up and when I see an astrophysics problem it goes down😂😂

So I just learned that when buzz lightyear says to infinity and beyond he means 7.1 miles per second or faster

"That's pretty brilliant that people figured this out." "Yeah, it's called science." Lol! Great video

“What goes up, must come down” Musk’s Falcon 9 rocket: Hold my fuel.

Honestly, I love these short explainer videos more than the podcasts.

“One giant leap to get home” 😂 😆 💀

I love you Chuck but nothing makes me happier than when Neil asks you to do Math & you look like you just seen a ghost.

Through 8 months of covid19-quarantines, i have kept my self sane by watching the STATTALK channel on youtube, and i'm glad that i did, i learned alot, thank you guys for keeping all the space geeks updated.

Now I understand "To infinity and beyond!"

Chuck owning Niel was great. "You said, '96 MILES PER HOUR,' fool!"

Just to remind that acceleration is measured in m/s/s or m/s^2, what i mean is that m/s is the measurement of Dv, velocity difference or just velocity v. Also a=Dv/Dt=Dx/Dt/Dt=Dx/Dt2 (Dt squared) and thats why the measurement of acceleration is m/so, i mean seconds squared.

I'd love to see michael vsauce and NDT have a conversation.

More accurate rephrasing can go like: What goes up might come down Or not

You guys have an awesome dynamic. Plus, I love how Chuck was like "uh uh uh..." and then called you out on not knowing baseball (even though Neil just had a baseball episode)

I already knew this, but still, getting such an entertaining refreshing of it is always nice. And i love to improve my english as a side effect.

If RU-vid and this guy were around when I was in highschool, I think I would have enjoyed science more. I bet he had some great teachers.

Regarding air resistance - this a very important factor in rocket launches. If you watch any orbital rocket launch, you'll hear the announcer call out "Max Q" - Q is the letter assigned to air resistance. Rockets are designed for a certain maximum load of air resistance, so they have to take this in to account. The faster something goes in a fixed air density, the more resistance it has. But the higher something is, the thinner the air, so the less air resistance. Max Q is the point that these two balance - while the rocket is continuing to accelerate, it has gone high enough that the combination of air thickness+speed produces the highest air resistance. Once it passes Max Q, the air is getting thinner faster than the rocket is accelerating. Note that the Space Shuttle was capable of accelerating too fast! It had to throttle DOWN before reaching Max Q to slow its acceleration. Then once it passed Max Q, it would "go for throttle up". Another common misconception is that space is "high up". It isn't. A large portion of the Earth's population lives closer to space than to an ocean. Live in Portland, Seattle, Chicago, Dallas? You're closer to space than to an ocean. The air thins out *REALLY* fast - conventional airliners fly at an altitude that has air pressure about one quarter that at Sea Level. Concorde flew at an altitude where air pressure was about 10% sea level. The SR-71 Blackbird spy plane experienced only about 5%. (Which is why Blackbird pilots wore what were basically space suits - they were being shot at, so if the plane lost cabin pressure, they would die quickly without a space suit.) It is possible to achieve orbit at only 100 km (62 miles, 328,000 ft) altitude - you're above enough of the atmosphere at that point that atmospheric drag won't produce heating from going orbital velocity. You are also still experiencing roughly 97% of the gravity at Sea Level, though! So if you just went straight up to 100 km, you would feel nearly the same pull down as on the surface. To stay in orbit, you have to be moving sideways fast enough that you're "falling back down" at the same rate as the curvature of the Earth is going away from you. That's all orbit is - going sideways fast enough to continually NOT hit the Earth. Yes, there is some atmospheric drag at 100 km - enough that if you were put in to orbit there, the atmosphere would slow you down sufficiently to cause re-entry within a day or two. But not enough to be a serious heating concern. (The lowest "commonly used" orbital altitude is 250 km - that's high enough for a spacecraft to remain stable for at least multiple months.)

There's another way to break this 'law'. "Cats always land on their feet" "Toast always lands butter side down" If you glue toast butter side UP to the top of a cat and toss them up, both laws cancel each other out and the toast-on-cat can't ever fall back to the ground.

absolutely enjoyed this episode.

AMAZING CONVERSATIONS!

I really enjoyed this episode! 👍

South Sudan 🇸🇸 ❤️ star talk.

Your channel definitely deserves my subs!

Chuck catching an error on Neil's reasoning! Priceless!! Fastball is about 140 feet per second, so close enough

I thought Neil was going to talk about Alan Parsons. "What Goes Up ..." what a great song!

Every morning I'm watching this guy!

I love how when Chuck was asked the math problem, his answer was just reciting the problem back to Neil rather than answering it. lol

I can literally get old just watching every neil de gryse tyson's video on youtube

This channel deserves at least 7 billion subscribers

Brilliant! Interleaved learning 8:01

Chuck’s a card. Great reference to A Broncs Tail. Neil gave the best explanation of escape velocity.

You guys need more merch! I want to rep a startalk t-shirt!

It all depends on which Discipline is being researched e.g. they were narrowing it down to altitude. 'What goes down, must come up' is similar depending on which field of conversation is on the table. Finance, medicine, career,...

Great video as always.

"Now yous can't leave" - An analogy of a black hole "Look at me. I'm the one who did this to you, remember me" - An analogy of super massive black hole

Chuck i love the "A Bronx Tale" reference. Awesome movie!

Thanks for that Video Can you do a video on how to calculate this stuff Hi from Germany

I just love Neil and Chuck!

@Startalk First - love all these videos. Second - age goes up but never down.

First time on this show that I knew everything ahead of time because it makes so much sense

I implore you great gentlemen to talk more about lightning

"what goes up at 6.9 miles per second must come down" seems very catch phrase to me, i can't stop saying

I love how NDT asked Chuck like 5 times what 96-32 is and then just gave up and gave him the answer 😂

i love neil's face when he asked what the escape velocity of a black hole, like oooo spooky

That Bronx tale tangent on black holes by Chuck was his best ever

Fascinating

"Neglect air resistance" AH! took me back to high school :p

Love the Bronx Tale reference! LOL.

2:55 Neil says ‘achcha!’

Props to Chuck for bringing in A Bronx Tale!

Love this guy what an educatior and inspiration not only here on earth and now threw all space and time.....hehe..

The signing for the Yankees quip was greatn Chuck is so effortlessly funny!

Up is any direction pointed away from the center of gravity, down is any direction pointed towards the center of gravity. Firing bullets in the air not only must you take air resistance into account but, also earth rotation.

What a beautiful day, Kurzgesagt and Star Talk uploaded a new vid

Imagine the astronauts missed the moon's entry point and then got pulled back to Earth "Nooooooooooooooooooooooooo"

🤫🤫🤔🤔🤯😎🙃🙂😍love these quick "Now you know" vid & da teachers!!

Already knew that, but still needed to hear it from Neil.

yes yes yes another explainer video. I wait for these with PASSION. Thank you Neil for spreading knowledge

These guys are so funny together.

Pre-space statement: "What goes up, must come down" Earth: Yeah! Human: Not exactly Sun: Pardon? Voyagers, Pioneer 10 & 11: Leaving the sun Milky Way: Cool . How about 100000 light year? Human: Wait and see

Yes.. that “A Bronx Tale” reference 😅🙌🏾💯

8:59 "It's time we retired that statement" Alan Parson's Project begs to disagree.

Very good on the bronk tail

Follow-up question. For example with Apollo 13, or with Voyager 1&2 doing gravity slingshot assists how does that factor into the escape velocity conversation Neil and Chuck just had?

What about the terminal velocity in that first example? There's a point where it won't pick up any additional speed on it's way back down.

Awesome explanation. I’d would like to hear your thoughts about this old saying “as above so below”. Is this an universal rule?

“What goes up…mustn’t necessarily come back down…spinnin’ wheel got to go ‘round” …yeah baby!

I saw chuck on tv last night, kinda fangirled

Just when I wanted to say "Duh, it's a prespace saying" you're saying it with me 🤣 You do not dissapoint.

Could you do a talk about skydiving and parachutes? In a numerical analysis course, there was an assignment question about a skydiver and a parachute. If I recall my results correctly, the immediate change in surface area caused a near immediate drop in speed, but then shortly afterwards, did speed up a little. I found this baffling and counter intuitive, hence, my suggestion :)

A comedian and a scientist! A wonderful combination!!!😂😂

Great video uploaded on RU-vid👍👍

U know space and all other space curiosity questions is complicatenand hard to explain but no one can explain better them Niel.....thats what i like about him......he explains very clearly... This one I had never imagined or thought about the way niel is telling.. anyways ifk if that information is helpful to general space geeks to use but it is a great humourous topic

About the bullet's return velocity....I may be wrong, but on it's return wouldn't it accelerate (~9.8m/s/s) until it reaches terminal velocity (~170mph)... provided the bullet is falling stable point first, and not tumbling, bringing the top speed down a hair.

Some clarification. To say the escape velocity of the "surface" of a black hole is the speed of light is kind of misleading, since it gives the impression that if you can go faster than light, you could escape. But this isn't considering relativity. In relativity, you have to consider something called a spacetime path. Normally if you map out every possible spacetime path you could take onto a graph, where every line is at some angle from the normal [which would represent rest velocity], those lines would form cones, with the vertex angle of that cone being 45 degrees. Those 45 degree lines represent the speed of light [the angle between each line and the normal would be a hyperbolic cosine of each one's length]. Everything inside that cone represent every physically possible place you could be at any given time. In other words, it's every place you can go to in your future. As you approach a source of gravity, your light cone skews towards it, which is why they attract things. When you reach the event horizon of a black hole, the only possible spacetime paths you could take are those that point inside it, or to travel at 0 velocity with respect to the event horizon. In other words, there is no possible path you could take that would allow you to leave. Once you cross the event horizon, every path points inward. Even if you could travel faster than the light speed, it wouldn't matter. Faster speeds don't give you access to other paths outside of your light cone, because each point on any given line could only ever follow the curve of a hyperbola, which is why spacetime diagrams use hyperbolic trig functions. Increasing your speed would still take you along the same path as light, which can't escape the black hole. TL;DR: Every possible direction you can take from the event horizon points into the black hole, so it doesn't matter how fast you are, you're going in whether you like it or not. Escape velocity is a purely classical concept. It works great for almost everything. Black holes and massless things are the reason there's an _almost_

chuck you are awesome... your jokes are on point 🔥🔥🔥

I'm totally lost at the "at infinity" bit. Is that time, distance, and where does it apply? Sorry my bad, I've watched it several times and don't understand the context.

*They cut out the part where Neil taught Chuck how to subtract...* @2:55

Genius as always

I roll my eyes when he contradicts a saying...then I listen to the program through and roll my eyes at my reaction 😅

I like the little music that plays when it comes on..idk y😂

In the rifle bullet example, isn't there something called 'terminal velocity', where the max falling speed is reached?

2:35 how I feel all the time🤔🤷‍♂️

Thanks Chuck, very *Nice* jokes.

best duo

4:40 "As the thing gets higher, it gets further away from earth" - Damn, Snoop Dogg is an astronaut

Sziasztok ! Az ördög jobb és bal keze! Királyság! OK! Imádlak benneteket!

I've always loved science but Neil has made me so much more interested.

So every object on Earth sticks to the surface of the Earth due to what we call gravity (less than escape velocity). But what actually is gravity? 1) Is gravity a consequence of curved space time due to Earth? 2) Or is gravity prevelant due to the acceleration of the earth through space along with the solar system? Is it both or What actually is the cause of gravity beacause it's not a force right?

I'm currently reading "Death by Black Hole And Other Cosmic Quandaries" and I must say that it's quite interesting.

To be fair to those objects left on the moon and Mars, they did come down as well - it's just that they established a new 'down'.

I had an actual realsies LOL moment from 10:46 -11:05 😂

Chuck is actually right to warn against firing a gun into the air. Between 1985 and 1992, doctors at the King/Drew Medical Center in Los Angeles, California, treated some 118 people for random falling-bullet injuries. Thirty-eight of them died.

My favorite people on Earth ♥️♥️♥️

Hello I have a question...if you take a Video of a light[beam] and fast forward or increase the playback time does that make the beam in the video move at speeds faster than light in the context of the video and not how it's perceived outside the video