illustration of the Artemis II flight path

Apr 3, 2026 2:54 PM

Kyzyl

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75351

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384

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6

artemis

moon

nasa

I see where they got lost for a minute. Been there.

1 week ago | Likes 49 Dislikes 1

This just makes what they accomplished in the Apollo program all the more impressive.

1 week ago | Likes 5 Dislikes 0

1 week ago | Likes 14 Dislikes 1

Dang, can you not comment from your favorite folders on mobile anymore? ReverseofthisGIF.gif

1 week ago | Likes 3 Dislikes 0

MATH!

1 week ago | Likes 1 Dislikes 0

from this illustration, I don't get the "farthest distance from Earth man has been" thing. What am I missing?

1 week ago | Likes 1 Dislikes 1

Based on where the moon is in its orbit (it's not always exactly the same distance from earth) and how far they're going around the moon, it will put them at a farther distance from the earth than any of the Apollo astronauts ever went. They say that, when they reenter Earth's atmosphere, they're going to be doing the fastest reentry ever, which means it'll be the fastest any human has ever moved (at least relative to the Earth)

1 week ago | Likes 2 Dislikes 0

1 week ago | Likes 2 Dislikes 0

Crossing the moon trajectory is gonna be like "Oh shit, we gotta go back, forgot the batteries for the camera!"

1 week ago | Likes 4 Dislikes 2

I like how they impact with the Earth and end all of existence. Ò_o

1 week ago | Likes 33 Dislikes 2

Sliding the maneuver node around until they get an interception target

1 week ago | Likes 4 Dislikes 0

Definitely time I spun up Kerbal Space Program again.

1 week ago | Likes 4 Dislikes 0

Children of a Dead Earth is a fun game. Hard af, but really instructive on orbital mechanics.

1 week ago | Likes 3 Dislikes 0

Looks like they are gonna get hit by the moon, very risky

1 week ago | Likes 1 Dislikes 0

After this mission are they planning to land on the moon again?

1 week ago | Likes 1 Dislikes 0

Here’s some real time info on where they are., currently less that 180,000 miles away from the moon. https://www.youtube.com/live/6mtZ4mN-zhw?si=fRLdo-1k3-Vm_B1u

1 week ago | Likes 1 Dislikes 0

I just hope, when they get to the far side of the moon, that they have to balls to say on the radio..."we've reached the far side of the moon, now how about releasing those Epstein files!". Instant legend.

1 week ago | Likes 5 Dislikes 1

Orbital dynamics experts are amazing. Lots of very un-intuitive paths.

1 week ago | Likes 6 Dislikes 1

(But our orbital dynamics people are from ESA :-)

1 week ago | Likes 2 Dislikes 1

Hitting a moving target, while in motion.

1 week ago | Likes 23 Dislikes 1

They forgot to yell Kobe during launch. That's why they ricocheted back to Earth.

1 week ago | Likes 3 Dislikes 0

It helps when the motion is very predictable and doesn't change suddenly.

1 week ago | Likes 8 Dislikes 1

True. Just remember it took Newton to figure that one out.

1 week ago | Likes 3 Dislikes 0

It was several people, and moreso Kepler. Kepler formulated the elliptical descriptions of orbits based in large part on Brahe's meticulous observations. What newton did is tie things together via gravity.

1 week ago | Likes 4 Dislikes 1

You're not wrong. Newton just slammed the book down on everyone.

1 week ago | Likes 1 Dislikes 1

Single digit velocity seems kinda slow, no?

1 week ago | Likes 6 Dislikes 5

sure but those dots are really only moving a small distance on your screen

1 week ago | Likes 3 Dislikes 2

Not according to the unit. We usually see m/s, not km/s so factor 1000 higher

1 week ago | Likes 6 Dislikes 1

I suppose any velocity they gain they have to slow down from - might not be practical to go too fast

1 week ago | Likes 5 Dislikes 2

This! Every drop of fuel comes with a price, so you accelerate as little as possible.

1 week ago | Likes 3 Dislikes 0

It's listed in kilometers per second. 1 kilometer per second = 2236.9 miles per hour.

1 week ago | Likes 10 Dislikes 1

1 week ago | Likes 2 Dislikes 3

I don't know physics but would the moons path or anything change because of the introduction of a new satellite for a moment? The rocket is just using the moons gravity, so shouldn't affect anything, right?

1 week ago | Likes 12 Dislikes 2

Love that dude! So smarts and dumbs it down so nicely that i can understand it!

1 week ago | Likes 2 Dislikes 0

It does alter the path of the moon, but the change is way too small to measure. Remember, too, the moon also gets hit by meteors, like earth does, which alters the path to an infinitesimal degree.

1 week ago | Likes 4 Dislikes 0

I feel like it's one of those there's where technically, to the degree of some tiny-tiny decimal it affects it, but not to any meaningful degree. The difference in mass is pretty large.

1 week ago | Likes 20 Dislikes 0

You got it

1 week ago | Likes 8 Dislikes 0

Yes, technically. But their relative masses are so different that it effectively doesn't matter.

1 week ago | Likes 4 Dislikes 0

What others have said, what you're saying is technically correct, but in the same way that it's technically correct to say that a marble has a gravitational effect on a human.

1 week ago | Likes 6 Dislikes 0

The difference in mass is so ridiculously enormous that there wouldn't be any practical effect.

1 week ago | Likes 9 Dislikes 0

Yes.
But the total effect is if you are running along, and a mosquito bounces off your forehead. How much do you slow down?
OK, now think less than that. Much less.

1 week ago | Likes 8 Dislikes 0

And the mosquito doesn't even touch you, it just flies past you.

1 week ago | Likes 3 Dislikes 0

Ok question, how much fact do u want. Cuz yes. It will. Each item, any item, anything with mass, also affects gravity and hence, affects the pull on other objects in space, so yes indeed, the spacecraft DID affect the moons gravity and(by consequence) the orbital path. But to SHOW how much effect it had, U would likely need a couple thousand decimal points (And multiple quantum computers) to calculate how much, or if said effect would even be noticed in the next 15trillion years....

1 week ago | Likes 3 Dislikes 0

So... for easier TLDR version. NO. By way of saying that it has/had ZERO effect (by which I mean as close to zero without actually BEING zero) on the moon. But (VeryLongLoveToRead version) yes it did, BUuuuuuut....

1 week ago | Likes 2 Dislikes 0

F=ma

1 week ago | Likes 3 Dislikes 0

Actually in this case it’s F = (G*m1*m2)/r^2.

1 week ago | Likes 5 Dislikes 0

If I'm being honest, rocket science seems hard

1 week ago | Likes 187 Dislikes 1

Orbital Mechanics

1 week ago | Likes 1 Dislikes 0

Not really. There's only 2 things you need to work out any equation. 1) gravity is a bitch and you can't stop it. 2) speed of light is a road block on whatever you think you can do. There is also an addendum, "In space, no-one can hear you scream."

That is all... oh yeah, musk is a fucking idiot.

1 week ago | Likes 4 Dislikes 1

If I'm hard, being rocket seems honest.

1 week ago | Likes 9 Dislikes 0

How hard can it be. I heard about a tangerine who learned everything there was to know about it in 30 minutes. /s on believing the tangerine.

1 week ago | Likes 1 Dislikes 0

This isn't rocket surgery. It's orbital mechanics. Which is pure math. This is just a potting of that math for visual reference.

1 week ago | Likes 1 Dislikes 0

I was in the 2nd year of graduate school in Physicx for an MS degree, and *that* is when I learned how to be a rocket scientist, and it happened in 90 minutes. Thanx, Dr. Brehme! It's a great story and perhaps I could tell you sometime.

1 week ago | Likes 2 Dislikes 1

Physics was great right up until differential equations when they were like "1+1=2 right? but if we subtract a + sign from each side we get 11=1-+ and from this we can calculate why a rope sages in the middle"

1 week ago | Likes 2 Dislikes 1

One of the best parts of learning physics was learning that solving differenial equatiion didn't matter anymore since they'd already been solved. We happily just worked with the results.

1 week ago | Likes 2 Dislikes 0

The rockets are the easy part, the math is a bitch.

1 week ago | Likes 1 Dislikes 0

Well it is rocket science—

1 week ago | Likes 1 Dislikes 0

It’s not really “hard” so much as it’s just “weird”…

You don’t drain fuel; you push it out.
You don’t go down to go lower; you go backwards.
You don’t speed up to go higher; you increase drag.
And just in case you need more energy, you can just steal some from a nearby rock.

There’s math for all that, and tools to assist… but mostly it’s just knowing that spaceflight is an unusual case for all the usual physics rules.

1 week ago | Likes 6 Dislikes 2

You do speed up to go higher. Speeding up in any part of a non-hyperbolic orbit will increase the altitude of your apoapsis, periapsis, or both, depending on your position in the orbit. Not sure what you mean by increasing drag being linked to speeding up?

1 week ago | Likes 2 Dislikes 0

"Speeding up" meaning specifically increasing your prograde velocity, to be clear.

1 week ago | Likes 2 Dislikes 0

So that one’s real fun, though I forget the exact timing details… It’s a cheap way for satellites to raise to a higher orbit.

Increasing drag (such as by angling solar panels) at the right time in the orbit changes eccentricity with a disproportionate change in kinetic energy. Periapsis lowers, but apoapsis raises, essentially for free.

With a small burn at periapsis, the Oberth effect magnifies the altitude gain, then a small burn at the following apoapsis circularizes again.

1 week ago | Likes 2 Dislikes 0

Burning for oberth, then using aero forces to raise peri makes sense. I would imagine that would still lower your average altitude, if less so than the dip into a lower peri would. Definitely still a huge benefit to keep your craft out of thicker air without spending any fuel if reaction wheels can handle it.

1 week ago | Likes 1 Dislikes 0

oh come on, it's not brain surgery.

1 week ago | Likes 28 Dislikes 2

Hahaha

1 week ago | Likes 2 Dislikes 0

That is definitely not rocket surgery

1 week ago | Likes 7 Dislikes 0

Mitchell and Webb, just as I suspected. Excellent bit.

1 week ago | Likes 2 Dislikes 0

Kerbal Space Program will teach you 98% of what you need to know. Take a graduate degree program if you need that last 2%

1 week ago | Likes 55 Dislikes 0

Feel like they should have an elective in KSP for aerospace engineers.

1 week ago | Likes 1 Dislikes 0

Pfft that last 2% is called "MechJeb", NASA should just use that. /s

1 week ago | Likes 9 Dislikes 0

The last 2% is done by a computer anyways.

1 week ago | Likes 14 Dislikes 1

No joke. I literally did this. Played KSP. Loved it, went to grad school to finish up my masters degree in astronautics. I haven't used my degree for space stuff, but it was fun to master KSP!

1 week ago | Likes 3 Dislikes 0

Part of me feels that Kerbal is harder than that last bit.

1 week ago | Likes 3 Dislikes 0