Author Topic: The Artemis Program  (Read 5211 times)

Offline bknight

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Re: The Artemis Program
« Reply #30 on: November 20, 2022, 05:38:25 PM »
I was tinkering with finding the point at which the Moon's gravity becomes larger the Earth's.  Solving a simple quadratic is not something that I have accomplished lately (15 years or so) but I calculated if my math was correct that point is about, from memory as the calculation sheet is gone, about ~4500 Km from the Moon.  This sounded too low and that prompted me to discard the sheet.  Anyone have a better figure?

Not OTTOMH. But the Apollo Flight Journal would have transcripts discussing it for the various missions.

Quote
ETA: I see that at 0938 CST that the velocity has decreased to 451 mph today.

ETA1: I see that at 1106 CST the velocity has decreased to 420 mph but the distance to moon is decreasing more rapidly perhaps the number is ~44060 miles currently (70908 kph)  I might have made a decimal error ~45000 Km.

I note that Artemis has gone beyond the Moon's orbit as well. And its encounter with the Moon is now about 15.5 hours away...I think I'll be tuning it to that.

The trajectory is very different than that of Apollo.  Currently 1632 CST velocity is 301 mph distance to Earth is 233315 m.  now the mean distance to the moon is 238900 m, but it may be closer in this orbital position so I'm not sure it is beyond the Moon. The burn will be about 8 hrs. currently and the burn will occur beyond the Moon.

ETA: from https://history.nasa.gov/afj/ap11fj/11day4-approach.html
Quote
PAO:This is Apollo Control at 62 hours, 29 minutes. The Flight Surgeon reports that the crew appears to have been asleep now for about the past 30 minutes. The spacecraft appears also to be holding its Passive Thermal Control attitude very well and at this time Apollo 11 is about 32,000 [nautical] miles [59,000 km] from the Moon, traveling at a speed of 3,782 feet per second [1,153 m/s]. In the past 50 minutes or so, we've seen that velocity increase about 10 feet per second [3 m/s], going from 3,772 feet per second [1,150 m/s] to the present 3,782 [1,153 m/s], as the spacecraft continues to accelerate toward the Moon. The Change-of-Shift Briefing following this shift will occur at about 11:15 pm Central Daylight Time. Flight Director Glynn Lunney and his team of flight controllers are coming on now, being debriefed by the Eugene Kranz team, and that shift change will be occurring shortly here. The new capsule communicator will be astronaut Ron Evans. At 62 hours, 30 minutes, this is Apollo Control.{/quote]

Artemis at over 100 hr. is still slowing now 287 mph that translates to 128 m/s in comparison.
« Last Edit: November 20, 2022, 06:08:12 PM by bknight »
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Offline gillianren

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Re: The Artemis Program
« Reply #31 on: November 21, 2022, 11:33:07 AM »
I really don't understand looking at current events and thinking, "Yes, I trust an Elon Musk-run company to be handled well."  I'd far rather trust NASA.
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Offline Allan F

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Re: The Artemis Program
« Reply #32 on: November 21, 2022, 11:57:28 AM »
I really don't understand looking at current events and thinking, "Yes, I trust an Elon Musk-run company to be handled well."  I'd far rather trust NASA.

I'm pretty sure he's not micro-managing things, just setting overall goals. He's not an engineer or scientist himself, he has people doing those things for him.
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Offline Peter B

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Re: The Artemis Program
« Reply #33 on: November 22, 2022, 03:46:52 PM »
I really don't understand looking at current events and thinking, "Yes, I trust an Elon Musk-run company to be handled well."  I'd far rather trust NASA.

I'm pretty sure he's not micro-managing things, just setting overall goals. He's not an engineer or scientist himself, he has people doing those things for him.

The micro-managing seems to be happening at Twitter ATM. Maybe that's a good thing for SpaceX? And Tesla?