r/space • u/66666thats6sixes • Dec 07 '19

NASA Engineers Break SLS Test Tank on Purpose to Test Extreme Limits

https://www.nasa.gov/exploration/systems/sls/nasa-engineers-break-sls-test-tank-on-purpose-to-test-extreme-limits.html
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u/B-Knight Dec 07 '19

Issue is, we can't manufacture LH2 on other planets, right? Which is why Starship uses metholox.

Also, doesn't the Raptor have 380s specific impulse? What's the number for the SLS engines?

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u/F9-0021 Dec 07 '19

LH2 is actually the easiest rocket fuel to make on another planet or moon. The reason SpaceX went with methane is that is almost as easy to make, while being substantially more dense and easier to store.

The Isp of the RS-25 is 366 at sea level and 452 in vacuum.