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Artemis II Launch Day Updates

nasa.gov

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Re: Artemis II Launch Day Updates

#671

Post by scarecrowbob »

adamgoodapp wrote: post #638
jgord wrote: post #208

Regardless of whether this particular mission is perfectly planned, this is precisely the kind of thing that will help humanity outgrow the dark age of war, inequality and climate mismanagement. It is a noble endeavor - science, engineering and peaceful exploration hold the keys to our survival and prosperity. It is also important psychologically to our survival - a reminder there is a bigger pie, that we can solve h…

On the contrary, Whitey on the Moon still rings true.

Yeah, that's the take I have been looking for a spot to drop.

https://www.youtube.com/watch?v=goh2x_G0ct4

I believe that folks in the US are, by a large margin, the most highly propagandized group of people in history. It's hard to watch stuff like this.

It's not that I don't understand that comparatively space exploration is small compared to the associated costs of the boots that might hit the ground today.

Re: Artemis II Launch Day Updates

#672

Post by qingcharles »

dylan604 wrote: post #513
qingcharles wrote: post #490

Earlier quoted context omitted.

I got super, super lucky and managed to get VIP tix for the last one. IIRC I took these pics on my iPhone 5 https://imgur.com/a/Mlyxk9u

wow, that shot of it sitting on the pad is much cleaner than I'd have expected from that phone. i'm envious

I cheated somewhat. I had some good binoculars with me that day and I was juggling those in one hand while holding the iPhone to the eyepiece :)

(and I checked, it was iPhone 4 not 5)

Re: Artemis II Launch Day Updates

#673

Post by devilbunny »

sd9 wrote: post #320

Minutes after launch they reached "ten thousand miles per hour". That's 2.78 miles per second. Nuts. No doubt the speeds go even higher later too. I'm sure people here are already familiar with the speeds these things go, but that's the first time I've confronted a fact like that and it blew me away.

I knew someone who knew someone, so I got to see STS-133 from the VIP area.

Nine minutes after launch, it was in orbit.

Nine minutes.

Re: Artemis II Launch Day Updates

#674

Post by peterleiser »

reactordev wrote: post #662
layer8 wrote: post #538

Earlier quoted context omitted.

It’s absolute in the sense that you can determine your acceleration without any external reference. You feel a certain force (like what you feel in an elevator). That’s your acceleration. You don’t accelerate relative to Earth, or relative to anything else. You accelerate relative to when you wouldn’t be accelerating (your inertial rest frame, a state of free fall). If you are in space accelerating and the Earth woul…

"You feel a certain force" is that true in zero-g?

Yes

Re: Artemis II Launch Day Updates

#675

Post by Larrikin »

krapp wrote: post #591
Larrikin wrote: post #566

Earlier quoted context omitted.

I guess we should collectively give up on space. The people at NASA are all doing hard science for that notoriously bloated government salary.

We actually should. By "we" I mean just Americans, though. Leave the hard science to cultures that still have an educated populace and a government that believes in it. Americans are going to need that money to fund the holy war in Iran over the next decade and to build out Trump's Epstein Memorial ballroom. All that gold filigree is expensive. If I were a Real Scientist working for NASA I would have seen the writing…

Meh, sounds like you are not American so telling people in the US to just give up on everything is boring and self serving.

If you do have a vote in the US, then you have options to try to make things better. Complaining about pedophiles and people on ketamine in the government is a valid (but extremely small) form of affecting change, but the doom and gloom of everyone should just give up helps no one.

Re: Artemis II Launch Day Updates

#676

Post by angelgonzales »

ryandrake wrote: post #378
ls612 wrote: post #325

Earlier quoted context omitted.

NASA has been well treated by both parties in general, with their budget rising faster than inflation most years. This administration also appointed Isaacman to be the NASA administrator which I think is a 10/10 choice for that job.

All of NASA's climate work is under attack by the current administration.

I’d argue that NASA should not have ever got into studying climate science, it should be a responsibility of NOAA. NASA should be focusing on NEP, atmospheric satellites, better aircraft, making life interplanetary and astronomy.

Re: Artemis II Launch Day Updates

#677

Post by ls612 »

dylan604 wrote: post #607
sd9 wrote: post #320

Minutes after launch they reached "ten thousand miles per hour". That's 2.78 miles per second. Nuts. No doubt the speeds go even higher later too. I'm sure people here are already familiar with the speeds these things go, but that's the first time I've confronted a fact like that and it blew me away.

Artemis II won't fly by the moon until Day 6, but it only took Apollo 8 to Day 4 to get to the moon. Looking at the wiki for Apollo 8, it shows the moon was 218k miles at launch while they said the moon is currently 240k, so it still looks like Apollo was moving faster than Artemis.

Apollo put a lot more burden on the Service Module than Artemis plans to put on the Orion. Apollo put the CSM/LM into a low lunar orbit while Artemis plans to put Orion into a high lunar orbit and make the Starship carry a lot more delta-V to land from a much higher velocity (and then accelerate back up to that velocity when coming back).

On top of that there weren’t really solar panels in the 1960s so the Service Module had to carry tons of chemicals to produce electricity, as well as extra fuel for all of that weight. As a result it was massively overbuilt compared to anything we’d try today and even so had to take an expedited flight path to the moon of 3 days in order to conserve operational lifetime. Artemis does not have nearly as severe constraints on either the Orion or the future Starship and so can afford to take a more fuel efficient 5 day coast up to the Moon and make the design tradeoffs on Orion that that entails.

Re: Artemis II Launch Day Updates

#678

Post by glenstein »

russdill wrote: post #256
glenstein wrote: post #231

Earlier quoted context omitted.

So did they! And they showed their work. So far you're just beating around the bush. What would would help is if you said something like "Maceij says modeling a different entry approach on computers is no substitute for a bona fide re-entry testing a new design, but that's incorrect because _____."

I would, except all Maceij is providing is "vibes" and much of the official report is redacted.

That's not even remotely true. They talked in great detail about heat shield fragmentation Artemis I, it's failure modes, the prospect of it getting worse with new designs and a number of other things at much greater detail than you are. Your comments show a fraction of the effort and detail of the thing you're criticizing and you could have made your best argument five comments ago if you were ever actually going to instead of beating around the bush with these substance free drive bys.

Either theres a functional literacy issue here keeping you from understanding what it means to express a substantive thought or you overestimate other people's toleration for writing checks promising unmade arguments that never cash. You can't keep buying time with nothingburgers.

Re: Artemis II Launch Day Updates

#679

Post by tombert »

WalterBright wrote: post #377
_DeadFred_ wrote: post #232

Earlier quoted context omitted.

To your last point, because DOGE shut down programs in a such a way as to make that impossible, to the point they chose to let food rot, let medicines go bad, and stranded Americans overseas working on the projects without a way home.

It's still a non-profit.

That's debatable. Musk bought his way into politics and shut down USAID very specifically because USAID was investigating him [1]. Oh, and he used his position in DOGE to assist in making sure that government contracts went to his companies, or licensing out his SpaceX workers when his idiocy led to a shortage of air traffic controllers [2], which was very obviously a publicity stunt if nothing else.

So it's a product that was bought and used to enrich a single person. Sure seems like a for-profit to me, at least in this administration.

[1] https://www.newsweek.com/usaid-elon-musk-starlink-probe-ukra...

[2] https://www.independent.co.uk/news/world/americas/us-politic...

Re: Artemis II Launch Day Updates

#680

Post by pitched »

XorNot wrote: post #496
PaulDavisThe1st wrote: post #322

Earlier quoted context omitted.

> And with modern forms of entertainment "We're sorry, your Prime subscription appears to have cancelled. Would you like to renew it? We can send you a text message to get this started ..."

I wonder if Starlink works if the dish is above the satellites. Technically GPS can work from the moon.

Starlink uses phased arrays pointed at the ground but lasers between satellites. So it wouldn’t be impossible to spin one around and have it bounce traffic to earth through the swarm pointing down.

But these satellites are very close to earth compared to the moon. It wouldn’t only save 0.3% transmit power vs just sending right to the surface. It’s very unlikely the consumer antennas could manage hitting an earth satellite from the moon.

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