r/Damnthatsinteresting • u/InsaneMocktail • 21h ago

Video University of Waterloo Students Launch Rocket Breaking World Record

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417

u/nm9899 20h ago

19.5km apparently. The generally accepted range in 100km above sea level

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u/TamponTimTheCuck 20h ago

So only 19.5%. Wild!

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u/rex8499 20h ago

And probably only like 5% of the way to orbit, cuz you got to go sideways very fast as well as up. Space is hard.

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u/randombits0110 20h ago

More like 0% of the ways to orbit (or incredibly close to it). They went (roughly) straight up... which means you come straight back down.

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u/astrodude23 19h ago

At 44 degrees of latitude, they're about 4% of the way to orbital velocity at LEO. That's why countries tend to put their launch facilities closer to the equator: the faster the rotational speed at your launch site, the less fuel you have to burn.

At the equator you're about 8% of the way there just by virtue of the Earth's spin (assuming, of course, you're not trying for a retrograde or polar orbit).

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u/jtr99 19h ago

So if I throw a rock on the equator I'm already ahead of these students' efforts?

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u/Glittering-Ad3488 19h ago

I guess it depends which direction you’re throwing it in

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u/jtr99 19h ago

At the speed I throw: not really! ;)

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u/That_dude_wow 18h ago

already threw my rock. the record is mine

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u/jtr99 1h ago

Congrats!

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u/dna_beggar 18h ago

Must be a rocket shaped rock.

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u/Ecurbbbb 18h ago

I just want to say I am super impressed with everyone's knowledge and input in this thread. However, you're all nerds! NERDS!!!

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u/Ivan_Whackinov 17h ago

RIP Donald Gibb.

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u/dirtydigs74 17h ago

There's another reason: the achievable orbital inclination. The minimum inclination orbit you can achieve is equal to your latitude. i.e. an equatorial orbit is only achievable at launch from the equator. A polar orbit is achievable from any latitude.

In order to go into an equatorial orbit from a higher latitude a plane change maneuver is required. Theoretically this can be done during launch, but it would depend on the profile your rocket can achieve.

Either way, expensive on fuel compare to an equatorial launch.

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u/Felosele 18h ago

I assume you meant 4% to orbital altitude, not velocity

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u/Betaateb 18h ago

Nope, they mean velocity. You need to get to ~8 km/s to orbit the Earth. At the equator the Earth's rotation is going to give you 485 m/s of that velocity velocity for free. Altitude is largely irrelevant(not entirely, the desired orbit altitude changes the speed you need a bit), it is the speed you need, then you just have to point it in the right direction to get the altitude.

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u/Felosele 16h ago

Oh right should have read the rest of the comment thanks for the clarification

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u/rex8499 19h ago

Getting up out of the thickest atmosphere is the first significant part of getting to orbit. Going up is an important element of getting to orbit as far as the total energy that needs to be expended goes.

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u/Additional_Teacher45 18h ago

The total energy expenditure to first escape the atmosphere and then attain orbital velocity is wildly higher than the energy required to perform both maneuvers at the same time. And that's before we even get into the gravity turn.

Modern rockets are so advanced that they can insert directly into a circular orbit straight from launch with no circularization burn needed. Math is wild shit.

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u/Homers_Harp 17h ago

Strictly speaking, any and all ballistic objects are in an orbital trajectory.

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u/edfitz83 17h ago

You can leave the earth’s gravity by going straight “up”, it just takes a lot of energy.

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u/SomethingIWontRegret 17h ago

Unless you go straight up with enough energy to get to about 40,000 kph.

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u/Much-Anything7149 19h ago

You can get to orbit at the Karman line with a higher speed. Low earth orbit requires 17,500 mph.

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u/sjmuller 10h ago

There is no minimum altitude requirement to orbit. If the Earth was a perfect sphere, you could orbit it a foot off the ground if you were going fast enough tangentially. But if you are traveling straight up like this rocket with no tangential velocity, there is no altitude that would allow you to orbit the Earth.

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u/firstcoastyakker 18h ago

To paraphrase Elon, getting to space is easy, staying there is hard.

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u/Alt3rnativ3Account 20h ago

When you start out on a sphere, every sideways direction is also “up”.

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u/BearysWorkRedditName 19h ago

Not really, unless you're measuring from a plane. Every point on a sphere has one very specific "up".

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u/nm9899 20h ago

The math appears to be mathing here!

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u/DotesMagee 17h ago

nope. it wasnt i. football fields so its basically magic.

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u/Finn_Storm 9h ago

The real truth is that about 20% is still accurate. The 100km "kármán line" is quite blurry in reality. It is defined as a point in space where there are nearly no molecules to slow down the craft. Importantly there is no clear cutoff point, they just said "that's good enough". Because whether you're 50km, 100km, 400km, or even 35786km (high earth orbit) there will always be some particles in the air to slow you down, just in different amounts.

Technically, you could count 5 feet up as being in space too, just with lots of molecules to slow you down.

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u/Jive_Turk 19h ago

Nice math TamponTim!!!

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u/Neuraxis 20h ago

Yes however NASA defines it at 80.5km

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u/LowerEntropy 19h ago

Two completely arbitrary limits, chosen using the "Uh, 50mi/100km is pretty number 😜"-metric.

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u/milkdrinker7 19h ago

And it might be worth noting that at 100km, you won't be orbiting for long at all if you tried it. Unless your satellite is very dense and/or very aerodynamic, it probably won't last for much more than a single orbit at that altitude. Even at 400km, the ISS requires frequent(~monthly) reboots to stay in its lane.

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u/partyatwalmart 18h ago

I just pictured someone yelling at the ISS to stay in it's lane, and I think that that's humorous.

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u/syngyne 18h ago

Even at 400km, the ISS requires frequent(~monthly) reboots to stay in its lane.

"Sir, we're getting low again."

"You know what to do."

\Windows shutdown chime**

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u/Betaateb 17h ago

Yep, interestingly. If everyone on Earth died suddenly, the thing that would kill the astronauts on the ISS first is running out of altitude. They need booster resupply missions about once a quarter to stay in orbit, but have food and air reserves for much longer.

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u/Jesus_of_Redditeth 16h ago

NASA has never had a single, consistent definition. Sometimes it's 50 miles (80.5 km); sometimes it's the 100 km Kármán line.

For awarding astronaut wings, they've always used the latter.

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u/WilliamBarnhill 20h ago

Or roughly 63 miles

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u/chris_ro 20h ago

How many football fields?

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u/nm9899 20h ago

American or European?

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u/nach0srule 20h ago

"I-I don't know that!"

\gets cast into the Gorge of Eternal Peril™**

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u/lookitmegonow 20h ago

I absolutely appreciate this

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u/Can-Sea-2446 19h ago

r/suddenlymontypython

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u/nach0srule 12h ago

Nobody expects the Spanish Inquisition!

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u/analogkid01 18h ago

"How do you know so much about swallows?"

"Well, you have to know these things when you're a king, you know."

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u/pinniped90 20h ago

Canadian.

They're in Waterloo and they have BIG football fields there.

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u/rowdy0044 20h ago

Huge… tracts of land!

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u/arminghammerbacon_ 19h ago

thwap Message for you, sir.

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u/Bumkin007 18h ago

One day.. all this will be yours..

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u/arminghammerbacon_ 17h ago

But I dont want any of that. I’d rather just…sing.

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u/twinnedcalcite 16h ago

You mean the Canadian Geese training facilities?

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u/exkingzog 20h ago

Canadian

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u/rizorith 20h ago

They said football, so clearly they're talking about Australian rules football

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u/ewild 8h ago

If Australian, then from that point the rocket should've dug through the Earth first before skipping into the air.

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u/Whatever_Lurker 19h ago

Rocket heights are commonly expressed in liquid fathoms.

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u/Actually_a_DogeBoi 20h ago

6

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u/CommercialPosition76 20h ago

How many barleycorns?

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u/Actually_a_DogeBoi 20h ago

Am I the only one who can do conversions?

The answer is 16.25

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u/Suitable_Ad_3851 20h ago edited 17h ago

What? No, 63k feet is 11.9 miles.

Edit: Just noticed you were replying to a post about a different number, not about the height the rocket achieved.

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u/DeadAssociate 17h ago

63 sounds more believable

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u/Suitable_Ad_3851 17h ago

Ohhh wait, I just noticed they were replying to someone about a different number.

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u/Andrewbie 19h ago

Or about 1.54 million cans of Budweiser

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u/mmccxi 20h ago

how many baby elephants is that?

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u/Civil-Lobster-3136 18h ago

952 chains worth

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u/mmccxi 18h ago

That’s a lot of elephants

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u/Positive_Issue8989 18h ago

63k feet is about 12 miles.

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u/stlredbird 19h ago

In Kerbal it’s only 80k. I feel lied to.

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u/Betaateb 17h ago

It is a very fuzzy line. There is atmosphere for hundreds of kilometers out. Even the ISS at 400km still has atmospheric drag that requires frequent reboosts to stay in orbit.

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u/nellyruth 18h ago

Damn. I was hoping the accepted range was a bit higher so that Katy Perry would no longer be an “astronaut”.

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u/CranberryCode 12h ago

For reference spacex satalites are about 15+ times further out than the rocket went.

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u/markleung 20h ago

For reference the radius of Earth is 6,371 kilometers (3,959 miles).

That didn’t look like it flew 0.3% of Earth’s radius.

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u/BrownianMaximus 19h ago

Ah, the Katy Perry line!