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Artemis II Launch Day Updates

nasa.gov

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Re: Artemis II Launch Day Updates

#871

Post by atombender »

bibelo wrote: post #796
layer8 wrote: post #424

Earlier quoted context omitted.

Escape velocity is 25,020 mph (6.95 mps), so not completely surprising. Note that escape velocity applies to a situation without continued propulsion and also without air resistance, but still you can imagine that the order of magnitude is similar.

Thank you for that precision "without continued propulsion", because when talking about rockets, physics teachers always talk about escape velocity, as if it was an absolutely necessary condition to escape earth's gravity. But can't you escape gravity slower, just by going higher and higher at lower speed? Like a plane? (ie not vertically, but at an angle)

If you don't accelerate, my understanding is that you will slow down. In other words, it takes more and more energy to escape orbit. Eventually, if you don't accelerate, your speed drops to zero and you "fall back down". Escape velocity is about how much energy you put into your motion, not the velocity as such.

Re: Artemis II Launch Day Updates

#872

Post by muskstinks »

JumpCrisscross wrote: post #300

April 6: flyby April 10: splashdown After that, the exciting work will be in Starship making LEO and testing propellant transfer (a humanity first) [1] and Blue Origin testing its rocket and lunar lander [2], both scheduled for 2026, to enable Artemis II (EDIT: III), currently scheduled—optimistically, in my opinion—for next year. [1] https://en.wikipedia.org/wiki/List_of_Starship_launches#Futu... [2] https://en.wiki…

They still need to prove that they can fire 33 of them in parallel reliable.

Time will show, plenty of ignorant decisions from Musk inbetween so yeah...

Re: Artemis II Launch Day Updates

#873

Post by whywhywhywhy »

birdsongs wrote: post #280
rpozarickij wrote: post #2

Direct livestream link: https://www.youtube.com/watch?v=Tf_UjBMIzNo

I feel like they really fumbled the video feeds, it was a mess. Rapid shifting of camera angles as it left the pad, black video, switching to a grainy video of the crowd during booster separation, and a hasty switch back well after they separated. Come on guys. You're going to the moon. You couldn't plan the launch camera / video feed better? This is how the world sees it, gets excited about it.

Quality just looked so poor too it honestly felt 90s quality on some of the feeds, will be criminal if they don’t sort their cameras out before the moon landing

Re: Artemis II Launch Day Updates

#874

Post by jackmottatx »

SyzygyRhythm wrote: post #681
JumpCrisscross wrote: post #300

April 6: flyby April 10: splashdown After that, the exciting work will be in Starship making LEO and testing propellant transfer (a humanity first) [1] and Blue Origin testing its rocket and lunar lander [2], both scheduled for 2026, to enable Artemis II (EDIT: III), currently scheduled—optimistically, in my opinion—for next year. [1] https://en.wikipedia.org/wiki/List_of_Starship_launches#Futu... [2] https://en.wiki…

Starship "making LEO" is not a significant challenge--the existing flights have explicitly targeted a (very slightly) suborbital trajectory. They could have done otherwise at any point, but for now it's more important to guarantee that the stage comes down immediately. None of their current objectives require more than ~1/2 of an orbit. Starship v3 flying will be a significant leap, though. It's the first with the Ra…

[dead]

Re: Artemis II Launch Day Updates

#875

Post by muskstinks »

JumpCrisscross wrote: post #800
jojobas wrote: post #795

Earlier quoted context omitted.

Judging by the fact it's 2026 you must be writing this from the Mars base.

> Judging by the fact it's 2026 you must be writing this from the Mars base SpaceX was started in 2001. It announced Falcon 9 and messaged its reusability ambitions in 2005. Falcon 1 wasn’t going anywhere because making rockets is too hard. Falcons 5 and 9 weren’t going anywhere because medium lift is a different ball game. Falcon Heavy wasn’t going anywhere because timing that many engines impossible. Reuse is impos…

They are very good in finding money from somewhere to afford all of this.

If this doesn't play out to be reducing costs for the avg american, Musk was able to get funded by the american tax payer nicely.

Re: Artemis II Launch Day Updates

#876

Post by muskstinks »

bdamm wrote: post #804
ActorNightly wrote: post #759

Earlier quoted context omitted.

Starship is just obscene. The thing is never going to work for its designed purpose once you understand what the mission looks like (basically insane amount of refuel dockings while the thing is in orbit)

Going to the Moon or Mars is a trojan horse. Starship's true purpose is to compete with airlines in trans oceanic flights. Musk has said so many times but then he intentionally obfuscates it with all the Mars and Moon talk. But remember that you heard this before it was widely realized to be true; Starship isn't about going to Mars. Starship is about going to China.

None of that makes sense.

Transportships even reduce speed to reduce costs.

If the payload doesn't pay for all of this, it was a huge R&D investmen from the american people to Musks scifi ideas

Re: Artemis II Launch Day Updates

#877

Post by bee_rider »

JumpCrisscross wrote: post #683
bee_rider wrote: post #645

Earlier quoted context omitted.

I think I mostly agree with the other comment by runarberg—Earth is the place to be. But it is also worth noting that even if we do end up colonizing space, Mars is still really pointless. Mars is not significantly more habitable than orbit. There’s some gravity: the wrong amount. In space, you can at least get 1G with centripetal force. In orbit, you are halfway to anywhere. On Mars, you’ve gone back down the well.…

> Earth is the place to be. But it is also worth noting that even if we do end up colonizing space, Mars is still really pointless. Mars is not significantly more habitable than orbit I’m not pitching a specific destination. And I’m not pitching exploration to the masses. Most people on the planet never have and never will leave their home country. If we want to go to space, we probably want a lunar base. > There’s s…

>> In orbit, you are halfway to anywhere. On Mars, you’ve gone back down the well

> In orbit you’re perpetually nowhere. On a surface you have in situ resources.

It’s the bottom of a dried-out well in the middle of nowhere, that’s not an improvement over just being in the middle of nowhere with a full tank of gas.

>> practical next step for space colonies would be large investments in additional space stations

> Practical next steps are lots of experiments in centrifuges and micro and low gravity. To fund and focus that you need a goal.

The at least semi-plausible goal is the asteroid belt.

Re: Artemis II Launch Day Updates

#878

Post by bee_rider »

storus wrote: post #737
bee_rider wrote: post #42

Earlier quoted context omitted.

I don’t have any questions about a mission to Mars, it is a stupid and pointless trip that I don’t want to ask any questions about. The Moon, I dunno, it’s at least in Earth’s gravity well so it isn’t like we’re going totally the wrong direction when we go there, right? At best it could be a gas station on the trip to somewhere interesting like the Asteroid belt, though.

Mars pushes the frontier (even if no one might survive the trip due to human body deteriorating), going around the Moon is meh - we were there ~57 years ago multiple times so what's the point?

Mars isn’t a frontier, it is a wrong turn that leads to a dried out toxic well in the middle of nowhere.

We should aim for the asteroid belt. Maybe we can mine them or something. It’d be less like a frontier and more like an offshore oil platform, but still, it is at least semi-plausible.

Re: Artemis II Launch Day Updates

#879

Post by DrBazza »

ck2 wrote: post #127
adamsb6 wrote: post #31

It is a bit chilling to watch these astronaut profiles having just read yesterday about the heat shield issues observed on the prior mission, and that this will be the first time we can test the heat shield in the actual pressures and temperatures that it will have to endure. Godspeed crew of Artemis II.

I had to watch "go at throttle up" on replay on the news in 1986 for the entire year, like almost every newscast I was only a teenager and it burned into my brain badly To this day cannot watch any launch with people onboard live

Same. I watched last night, UK time, and I couldn't shake the worrying feeling. I was relieved that they got into orbit. Now I can be a little bit excited until re-entry. That worries me for the same reason.

In the UK as a kid, when Challenger happened, our children's news programme reported it before the mainstream TV.

http://news.bbc.co.uk/cbbcnews/hi/sci_tech/newsid_2701000/27...

Re: Artemis II Launch Day Updates

#880

Post by Cthulhu_ »

SyzygyRhythm wrote: post #681
JumpCrisscross wrote: post #300

April 6: flyby April 10: splashdown After that, the exciting work will be in Starship making LEO and testing propellant transfer (a humanity first) [1] and Blue Origin testing its rocket and lunar lander [2], both scheduled for 2026, to enable Artemis II (EDIT: III), currently scheduled—optimistically, in my opinion—for next year. [1] https://en.wikipedia.org/wiki/List_of_Starship_launches#Futu... [2] https://en.wiki…

Starship "making LEO" is not a significant challenge--the existing flights have explicitly targeted a (very slightly) suborbital trajectory. They could have done otherwise at any point, but for now it's more important to guarantee that the stage comes down immediately. None of their current objectives require more than ~1/2 of an orbit. Starship v3 flying will be a significant leap, though. It's the first with the Ra…

I was curious since I hadn't heard from Starship in a while, but by the looks of it they plan to launch the first V3 later this month!
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