r/Damnthatsinteresting • u/InsaneMocktail • Sep 08 '26

Video University of Waterloo Students Launch Rocket Breaking World Record

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u/nm9899 Sep 08 '26

Very impressive, still only 20% of the way to space. Crazy perspective at this scale

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u/tonyhart7 Sep 08 '26

its only 20% ????? I swear the video got to atmospher already

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u/nm9899 Sep 08 '26

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

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u/TamponTimTheCuck Sep 08 '26

So only 19.5%. Wild!

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u/rex8499 Sep 08 '26

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 Sep 08 '26

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 Sep 08 '26

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 Sep 08 '26

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

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u/Glittering-Ad3488 Sep 08 '26

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

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u/jtr99 Sep 08 '26

At the speed I throw: not really! ;)

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u/That_dude_wow Sep 08 '26

already threw my rock. the record is mine

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u/dna_beggar Sep 08 '26

Must be a rocket shaped rock.

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u/Ecurbbbb Sep 08 '26

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 Sep 08 '26

RIP Donald Gibb.

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u/dirtydigs74 Sep 08 '26

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 Sep 08 '26

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

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u/Betaateb Sep 08 '26

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 Sep 09 '26

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

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u/rex8499 Sep 08 '26

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 Sep 08 '26

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 Sep 08 '26

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

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u/edfitz83 Sep 08 '26

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

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u/SomethingIWontRegret Sep 08 '26

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

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u/Much-Anything7149 Sep 08 '26

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/Alt3rnativ3Account Sep 08 '26

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

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u/BearysWorkRedditName Sep 08 '26

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

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u/firstcoastyakker Sep 08 '26

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

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u/sjmuller Sep 09 '26

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/rex8499 Sep 10 '26

Air resistance is going to burn you up even if the earth was a perfect sphere, so that isn't realistically possible. Just a theoretical discussion ignoring the realities.

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u/nm9899 Sep 08 '26

The math appears to be mathing here!

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u/DotesMagee Sep 08 '26

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

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u/Jive_Turk Sep 08 '26

Nice math TamponTim!!!

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u/Finn_Storm Sep 09 '26

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.