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"though many factors could ultimately affect Webb’s duration of operation." JWST also needs helium coolant with no possibility to recharge therefore limiting it
by julienchastang 5y ago
"though many factors could ultimately affect Webb’s duration of operation." JWST also needs helium coolant with no possibility to recharge therefore limiting its lifespan to ~10 years, I believe. Interesting about Herschel and L2.
- bryanlarsen 5y agoIIRC, the helium coolant is only used on one of JWST's 4 instruments. So if they run out of helium the other three can still be used.
- terramex 5y agoIt does use helium only as refrigeration fluid in closed cycle, it does not get depleted. Building a cryocooler capable of achieving so low temperatures without boiling helium off was a major hurdle in JWST development.
- vlovich123 5y agoIsn’t helium notoriously hard to contain without leakage even in a closed system?
- dnautics 5y agothat's hydrogen. IIRC from my chemistry days, Helium is hard to contain in plastic closed systems, but "generally OK" in metal tubing.
- shepardrtc 5y agoIt actually uses a closed system: https://webb.nasa.gov/content/about/innovations/cryocooler.html https://webb.nasa.gov/content/about/innovations/cryocooler.h...
- deleted 5y ago[deleted]
- jerjerjer 5y agoDoesn't liquid helium always evaporate?