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

What goes up, must come down…right? Neil deGrasse Tyson says not so fast. You’ve heard the phrase before but Neil and comic co-host Chuck Nice are here to provide an update to this classic phrase in the latest StarTalk explainer video.
To start, we take a look at the science behind the phrase. You’ll learn about the forces of gravity working all around us. Then, Neil and Chuck discuss why it’s time to retire the phrase, or, make it a little more scientific.
We explore escape velocity. Discover more about traveling to the Moon and Mars and why we don’t pack fuel to get to the final destination, we just pack fuel to get to a certain point along the way. All that, plus, Neil and Chuck provide an updated version of “what goes up, must come down.”
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!
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[@johnl119]

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

[@johnl119]

I would react rhe same way...actually I do react rhe same way as Chuck

[@ChrisSandtSmith]

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

[@Russia-bullies]

In what direction is down? 😀

[@ChrisSandtSmith]

@@Russia-bullies whatever direction is opposite from escape direction.... In other words, towards the gravitational force or "down"

[@prakharanand7012]

@@ChrisSandtSmith what about a situation where all spacetime is curved towards one point Where no matter u go in which direction , u move towards that point😂😂(uk wut is it right?)

[@ChrisSandtSmith]

@@prakharanand7012 well, in that case there would be no escape, meaning no escape velocity, meaning what goes, must come. The other dimensions are then irrelevant. Lol,

[@danishkhan198]

@@Russia-bullies is giving a reference to a VSAUCE video and y'all gave him a lesson.

[@tonemoreno763]

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

[@NukasCafe]

I honestly hate listening to him, hes not interesting in the slightest. At least to me

[@techking55]

@@NukasCafe hate is a strong word... Chuck makes easy for simpletons to understand science 😊 thou he is a great and wonderful person with Humour

[@munchiemac2895]

His comedy is garbage

[@NukasCafe]

@@techking55 its not that I hate him, I dont by no means. Occasionally he can be funny, but I come to listen to Neil and then you have Chuck who makes these dumb jokes that just gets old quick you know? Idk just preference I guess. I still like chuck but I think he should tone down his jokes honestly

[@iamhighandwhatisthis713]

I feel the same, he doesn’t seem to belong on these vids

[@komranbehbehani6379]

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!

[@SomeFuckinGuy]

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

[@daniel.franco]

This is comment is so confusing

[@whateverdude0838]

You my friend deserve more likes !!!!!!!

[@MrJim117]

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

[@JD987abc]

How about a T shirt that says...”Now you can’t leave.”

[@judsonkr]

@@JD987abc yous. "Now yous can't leave"

[@MrJim117]

@@JD987abc you could put that on the back.

[@GetawayFilms]

@@MrJim117 On the back of mine I want "I'm travelling over 7 miles per second, catch you never!"

[@The_Becomings]

@@GetawayFilms mmmm you're out of this world!

[@jagdishgohel2577]

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

[@gyozakeynsianism]

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

[@birdeee461]

Sir when will you review Nolan's recent film "TENET"? Second Law of thermodynamics.... entropy of the universe... reversal of entropy!!!... need some explaining. Thanks n Lots of Love in advance.

[@SirSethery]

I’d also love to hear his thoughts on it. All the little things in the movie like the car freezing blew my mind.

[@SHAWNiNJO]

commenting on this for visibility

[@tuzuharurakutu]

Don't forget nuclear fusion ;)

[@gyozakeynsianism]

More Nolan dumb-science BS. Ugh. Though I can't see how it could be any dumber than the first ~20 minutes of Interstellar, or the last ~20 minutes of Interstellar.

[@DetectiveWarden]

@@gyozakeynsianism Stop crying, it’s called science-FICTION for a reason, some people enjoy these types of fictional work even people who know about the scientific possibilities or are interested in them. Talking about the accuracy or what if’s can still be really interesting. You could’ve just kept scrolling but of course you’re one of those guys who just couldn’t ignore it and had to make an unnecessary annoying comment crying about Nolan’s movies.

[@joe.s2596]

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

[@mpatek4696]

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

[@orazmyratrejepgeldiyev1478]

this made my day😂😂😂😂😂😂😂😂

[@jamesmmcgill]

**"Spinning Wheel" played**

[@katiakatia2380]

Well, it will eventually fall down😄

[@VoltisArt]

Musk's last rocket: Hold my - Oh sh...!

[@obadaodeh1625]

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.

[@whackbag3606]

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.

[@John_Fisher]

Too be fair it was Neil, who gave Chuck a sarcastic eyeroll, that said "It's 96 minus 32 dude" but had forgotten that he had switched between different units and was wrong. While Chuck verbally flubbed, he knew that the problem as stated was that he had to deal with 96 mile/hr vs 32 meters/second and that the conversion wasn't something he could do mentally on the fly but could be worked out. As much as the dynamic is intentionally 'average guy' versus 'educated guy' to have an entertaining and interesting dialog, I think sometimes the 'average guy' isn't given enough credit.

[@KatieCatWalker]

It's how I look when he asks Chuck to do math but I take it like he's asking me 🤔😭

[@millefune]

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

[@shaan702]

“One giant leap to get home” 😂 😆 💀

[@oluwafisayo3676]

Now I understand "To infinity and beyond!"

[@s.p.7313]

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

[@BattleBunny1979]

vsause needs prep and editing, neil does this on the fly.

[@shkambjaka7570]

I dont think there would be much left to be understood after a video like that. You’d just need some alcohol and accept your life as it is.

[@daniellaytonmusic9865]

@Townspeople C well that depends on where we are! And where are we? Are we really we? *10 MINUTE TANGENT*

[@sphinxrising1129]

Who do you think does the work for Vsauce? Someone just like NDT. Vsauce is not a know-all genius (DUH).

[@mookdiddy418]

@@shkambjaka7570 right 😀😀😂😂😂

[@trippplefive]

If KZbin 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.

[@ramkoushik_vlogs]

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

[@GetawayFilms]

That is more like something you would write in religious text.. Vague and without proper explanation :D

[@jeinnerabdel]

@@GetawayFilms no, because although it was phrased without details, you can still prove it. Religion would still miss the last part.

[@GetawayFilms]

@@jeinnerabdel Due to scientific progress we can prove it yes... But prior to humans EVER having the technology.. EVERYTHING came back down.. Yet the physics remained the same You see.. YOU cannot prove it, because you cannot create anything that reaches escape velocity, so all your experiments would conclude that EVERYTHING came back down

[@jeinnerabdel]

@@GetawayFilms dude... The whole thread was a joke... If you want to go serious, then the word *might* on OP's post invalidates the whole entanglement you are making.

[@mxkaba]

Cue Vsauce music

[@renos4421]

Every morning I'm watching this guy!

[@AnonymousFreakYT]

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.)

[@0osaka]

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.

[@rebekahweber2413]

Are you that bored during Covid? , 🤭😄

[@birdoffire9]

I love it. That is something I would say that's hilarious!!!¡!!🤣😅😂😂😂

[@urduib]

That´s science mate. You solved 2 unsolvable problems by combining them. This should be taught in school

[@urduib]

@@rebekahweber2413 Are you always SO SERIOUS. You must be the funny guy at party´s. Hey let me guess öO hmmm your nick name is trigger ? nooo Triggered among friends

[@rebekahweber2413]

@@urduib I wait for a moment and pounce. I get it from my cat. Timing is everything.

[@michelerossi7121]

This channel deserves at least 7 billion subscribers

[@sherubdorji8883]

absolutely enjoyed this episode.

[@RPIdemon]

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)

[@pozzowon]

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

[@madrooky1398]

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.

[@vassilismichalakis1830]

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.

[@ciberiada01]

I really enjoyed this episode! 👍

[@makemoneynow5061]

Your channel definitely deserves my subs!

[@ZULEEPLAYZ]

AMAZING CONVERSATIONS!

[@so_es]

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

[@shreyanshupanda1219]

Great video as always.

[@Stick-a-fork-in-Gmorks-tort]

"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

[@rusteshackleferd8115]

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

[@Josh-sh6sq]

South Sudan 🇸🇸 ❤️ star talk.

[@oliverknowledge1229]

Brilliant! Interleaved learning 8:01

[@mirjanakatalina591]

I just love Neil and Chuck!

[@waleedgaming4910]

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

[@Kirbykin88]

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

[@theseeingkarp7958]

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

[@gyozakeynsianism]

I know right? Where's the Tyson/Nice 2020 shirts???!! Make America Smart Again!

[@mjj5704]

I implore you great gentlemen to talk more about lightning

[@twonumber22]

I've wondered how big or bright lightning might be on some other big superearth exoplanet.

[@eugeneoman]

Props to Chuck for bringing in A Bronx Tale!

[@kt420ish]

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

[@brenotm3337]

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

[@innoventions9465]

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,...

[@joshuatheobald6536]

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

[@hidayayusuf1029]

Smart huh 😂

[@seantratervel4885]

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

[@immaculateon3]

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

[@gyozakeynsianism]

Chuck Nice would be (maybe already is) a brilliant voice actor.

[@fabiomenezesvieira2802]

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

[@cduncan3713]

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.

[@98Nedeljko]

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

[@ToyaF82]

Fascinating

[@JD987abc]

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

[@theElrin]

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

[@juanjaimes5821]

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

[@chrisavenell1312]

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

[@shaileshkris]

2:55 Neil says ‘achcha!’

[@noahl6595]

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

[@HellaUtube]

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

[@sazuna4024]

Well that would be funny but just for one second until you realize that they would be a bit dead. Or shooting somewhere into nowhere. After all if they wouldn't hit the moon they would still be moving through space in a straight line. That would be a case of feelsbadman now we are going to die oh welp. Stuff happens.

[@gildedbear5355]

The first several moon missions were actually set up to do just that. They were on "free return trajectories" which means that if they didn't do anything when they were near the moon they would return to Earth orbit. The later moon missions did not use the same orbital paths because the free return limited the places they could land on the moon.

[@projectjt3149]

Apollo 13 has entered the chat

[@souvikroy6237]

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

[@HotelPapa100]

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

[@soloneptune5637]

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

[@pistitoth1363]

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

[@PHutch-me5bq]

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

[@snowthemegaabsol6819]

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_

[@James-ye7rp]

Hey Neil and Chuck, I am not sure where to ask this Gravity Question. People constantly talk about Gravity as a "Downward" Force. But, if gravity is an effect of mass, then Gravity, on Earth for example, is not directly downward, but an artifact of Downward Plus an Infinite amount of Angular Forces of Gravity because "The Earth" is not JUST below us. So, the question: "Is there an accounting of just how sideways gravity affects the relative downward force of gravity?"

[@Thetruthiscosmic]

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

[@anandhugopan]

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?

[@botlovingbeard6708]

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.

[@billygsterling6727]

Very good on the bronk tail

[@pan4909]

I saw chuck on tv last night, kinda fangirled

[@kofisarkodie9550]

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

[@VoltisArt]

All you did was change the time reference of the recording. Considering light travels the diameter of Earth in about 0.042 seconds, you couldn't build a screen large enough to display the speed of light in any meaningful way, even if you could photograph light itself, which you can't. Displaying it faster wouldn't be anything traveling faster. On top of that, you're limited by electricity, which moves at...wait for it...the speed of light, in whatever medium it's traveling. _All_ mediums are slower than a vacuum like space. You physically could not update the screen fast enough to _show_ the speed of light, even if you could make and power a screen that spanned the distance between Earth and the sun, across which light takes about 8.3 minutes to travel. The electrical speed delivering the signal for any given part of the screen moves much slower than light itself, and must spread from the point where the data is sent out, in a wave across the entire screen. Your astronomical unit-sized screen might take an hour to show one frame of your movie. (Rough guestimate on my part and probably massively generous for actual electronics, ignoring the resistance that would prevent this thing from displaying anything at this scale, no matter what kind of wires were involved.) The next frame takes another hour. Meanwhile, actual light just did 7.2 laps from the sun to Earth...and back. The old version of this discussion is swiping a laser pointer across the sky. That also didn't make light go faster, it just changed where it's (eventually) ending up faster than it could travel between two places, which is information, not energy or mass. Nothing traveled between the two target end points, only from the laser pointer to each of those places. Two people standing on planets at either end of that swipe couldn't know that they got that light at almost the same time, because they couldn't ever get information _from each other_ faster than the speed of light. The same applies for watering grass. You can easily swipe the stream from a hose faster than the water's coming out, but no water goes from where you started pointing, to where you finished pointing. It all came from the hose at the same speed. Even if we make the camera and video screen magical and throw out all realistic delay, it's still the same as the hose or laser. Two far-apart pixels lighting up quickly isn't the same as a "thing" traveling at that same speed. You can't beat the speed of light. No matter what.

[@tindraerikssonpasic]

These guys are so funny together.

[@erromaissaeelhilali5121]

Great video uploaded on KZbin👍👍

[@GetawayFilms]

Please link me to it

[@erromaissaeelhilali5121]

@@GetawayFilms kzbin.info/www/bejne/q3zVkHaZlL6nnNE

[@Bahlzeron]

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.

[@blasphem1a]

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

[@killllllllllllllerrr]

Man of culture, I see!

[@TheLaffy1]

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

[@sidsharma7383]

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

[@gonderage]

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

[@RayRay-zt7bj]

Love the Bronx Tale reference! LOL.

[@enquiryplay]

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.

[@diegofernandez4789]

Genius as always

[@vinnt_tnniv]

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

[@shivamgagad5674]

Thanks Chuck, very *Nice* jokes.

[@John_Fisher]

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'.

[@fromnorway643]

Flat earthers are unable to grasp that since they don't even get that "down" here on Earth is towards its _centre,_ whether you are in Europe, America or Australia.

[@EdreesesPieces]

In that case, what goes up, must go up more, because everything that falls down on Earth is going up relative to the moons surface

[@chepitaouyeah9090]

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

[@pushing2throttles]

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?

[@Johnny_0704]

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

[@clarkkelly5568]

best duo

[@negarina83]

My favorite people on Earth ♥️♥️♥️

[@cirkular2042]

*what goes up, must come down* Taxes: “I think not”

[@justinlucas9055]

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

[@janmacek5672]

This video raises more questions then it answers really

[@HuMansta001]

The dynamic duo strikes again....

[@chuckspubgm7258]

Is it possible that the “ big bang” event happens over and over???

[@kukuster]

How come both sides are of bad quality? How did you record it? :D

[@JF-py3vq]

What if u have 2 blacks holes warping space churshing does space move faster than light? Nd gamma ray vs black holes

[@mydoggylives]

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.

[@fulstaak]

Based on this information, and I know I'm throwing a curve ball here, but please explain how the Twin Towers were able to come down to the ground in 10.5 and 12.5 seconds, and how Building 7, a 47-story building, was brought down in 6.5 seconds. Because I still don't get it. All mostly at free fall acceleration. Falling onto their vertical axes, through the path of most resistance. At free fall. Neil, Chuck, you have the floor. You might want to interview Richard Gage on this one.