Shrike99 t1_isdoob6 wrote
Reply to comment by Vanilla_Ancient in SpaceX, NASA targeting separate Moon launches days apart by sasko12
>This is comparing a heavy lift manned-capable rocket to the falcon 9
Technically speaking, Falcon 9 is both heavy lift and 'manned capable' - though NASA prefers 'human rated' or 'crew rated' as they're gender neutral.
So to be more accurate, this is comparing a super heavy lift lunar-crew-rated rocket to Falcon 9.
>The payload must either be super small or it’s gonna take a looooong time to get there with a falcon 9 right?
This particular lander is small because it's a secondary rideshare payload, but Falcon 9 should be capable of sending somewhere in the range of 5-6 tonnes to TLI, which I wouldn't call 'super small'.
I'd also like to note that sending payloads to the moon slowly often takes more energy, rather than less.
For example, SpaceX's recent launch of KPLO/Danuri to the moon via a ballistic transfer, which is expected to take ~4 months required accelerating to 10,521m/s, while Artemis 1 will only accelerate to about 10,100m/s and will get there in ~5 days.
If you look at this animation of Danuri's trajectory, the reason why will become obvious - it starts by going out about 4 times further than the moon (Indeed, with a max altitude of 1.56 million km it has even gone past the L1 point), then targeting the moon as it falls back down.
This approach takes a lot less fuel for the spacecraft to brake into lunar orbit than going directly there - essentially you're making the launch vehicle do more initial work so the spacecraft has to do less.
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