View Full Version here: : Artemis limping to the Moon
glend
20-11-2022, 11:48 AM
Can someone explain to me why it is taking Artemis so long to reach the Moon? I have been watching the various trackers and the capsule is constantly slowing down (without thrust being applied), last time I looked it was going 750mph, after leaving Earth at over 21,000mph. . Perhaps the idea is to just place it within the Moon orbital path and hope it gets grabbed. I am sure there are people working on the orbital mechanics, but it just seems very different to Apollo era mission mechanics. I realise there are no crew onboard and no consumables being used up, but it seems to be taking twice as long as an Apollo transit. How is this progress?
mura_gadi
20-11-2022, 11:57 AM
A few things come to mind.
Its a test mission, right down to the commander dummies etc, may as well have a long time for testing purposes.
Artemis will have a capsule that can sustain a crew for up to 21days, Apollo did not have this luxury.
Artemis is using a gravity assisted approach and a two stage system not three stages that Apollo used.
I'm sure other will already be in the know or find a link to what's what though.
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One from the interweb
"Apollo burned a lot of fuel in exchange for a quicker mission. Back in the 60's the spacecraft had a very short lifespan, mostly limited by the capacity of the batteries. Nowadays battery capacity is much better, and so is solar panel technology, so missions can afford to spend an extra few days in exchange for saving on some fuel (weight).
If you look at unmanned probe mission to the moon, some take fuel economy to extremes, and take weeks to get there. Roughly speaking, you can get to most destinations in the solar system on very little fuel if you are prepared to wait (sometimes many years) for the right launch conditions, and can tolerate very long flight times."
Startrek
20-11-2022, 01:59 PM
Long duration unmanned mission to test out new spacecraft and systems for future manned missions
Plus an entirely different lunar injection trajectory and orbit than the Apollo missions. I think from memory it’s furthest point from the backside of the moon will be 71,000km , so a huge elliptical orbit
Re entry will be different than Apollo too , an intentional steeper entry angle to subject the Orion capsule to severe G force loadings, probably in the order of 10 to 12G’s
I too was waiting to see video of the Moon in around 3 days , just like I did watching all the Apollo missions from 7 to 17
Stonius
20-11-2022, 03:23 PM
Looking at the mission plan on https://www.nasa.gov/specials/trackartemis/ it appears more like they're shooting it into the path of the moon where it almost seems to stop before the moon comes past and sweeps it up.
DarkArts
21-11-2022, 01:13 AM
The NASA Artemis website explains the trajectory being taken, but is a bit short on comparison to Apollo.
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