Dette emne er markeret som "i hvile"—det seneste indlæg er mere end 90 dage gammel. Du kan vække emnet til live ved at poste et indlæg.
1richardbsmith
Here is recent release about James Webb and planet searching.
http://science.nasa.gov/headlines/y2010/14jan_planetsafari.htm?list1361091
http://science.nasa.gov/headlines/y2010/14jan_planetsafari.htm?list1361091
2richardbsmith
A help from NASA on comparing Webb and Hubble.
http://www.nasa.gov/externalflash/webb_hubble/
Bad Astronomy provided the link.
BA wrote, "Hubble is an awesome ’scope, but its life is limited. Heavy and huge, there’s no way to bring it back, and with the Shuttle retiring there’s no easy way to get to it. Eventually its gyros will fail, it won’t be able to be pointed, and then that’s that. "
What are the maintenance access plans for Webb?
http://www.nasa.gov/externalflash/webb_hubble/
Bad Astronomy provided the link.
BA wrote, "Hubble is an awesome ’scope, but its life is limited. Heavy and huge, there’s no way to bring it back, and with the Shuttle retiring there’s no easy way to get to it. Eventually its gyros will fail, it won’t be able to be pointed, and then that’s that. "
What are the maintenance access plans for Webb?
3richardbsmith
From comment #26 in the BA link:
"Now think about the JWST. Once it launches, that’s it. No fixes, no new experiments. No manned fix-it missions. Maybe robotic fix-it missions, less capable than manned missions, but then, probably not, unless there’s a real disaster.
Think about what the HST is doing now, that the original designers never thought of, or didn’t have technology to implement. No wonder the JWST only has a mission profile of 5 to 10 years. It’ll be obsolete and irreparably broken after that."
In other words there are no maintenance plans for Webb. I hope the mirror is ground correctly.
"Now think about the JWST. Once it launches, that’s it. No fixes, no new experiments. No manned fix-it missions. Maybe robotic fix-it missions, less capable than manned missions, but then, probably not, unless there’s a real disaster.
Think about what the HST is doing now, that the original designers never thought of, or didn’t have technology to implement. No wonder the JWST only has a mission profile of 5 to 10 years. It’ll be obsolete and irreparably broken after that."
In other words there are no maintenance plans for Webb. I hope the mirror is ground correctly.
