Re:NASA says Webb’s excess fuel likely to extend its lifetim...
by baq on Tuesday January 11, 2022 @02:23PM
(#29896442)
'terrestrial' is an issue in the context of JWST... as the wavelengths that it observes are absorbed by Earth's atmosphere.
wonder if we could put a telescope on the moon for $10B though.
Re:NASA says Webb’s excess fuel likely to extend its lifetim...
by mlyle on Tuesday January 11, 2022 @02:43PM
(#29896744)
Yes, infrared scopes on earth have challenges and are not equally viable for all wavelengths. But VISTA, UKIRT, IRTF, etc, cover a substantial amount of the near and intermediate infrared-- the latter two are high enough to reach into a reasonable amount of the far infrared.
Most of JWST's wavelength coverage is energies that terrestrial telescopes can do (just less well). It's not like Herschel which went into the far, far infrared (and had its life limited by liquid He as a result).
Re: Moon-- Why put a telescope down a gravity well?
Most of the discussion of telescopes on the moon I've heard has been about radio telescopes, where a huge hunk of rock between you and Earth can be a feature.
I mean, we'll still have some big terrestrial infrared 'scopes. And we'll be coming off 20 years of very good space infrared scope data... And we'll have had the smaller Nancy Grace Roman Space Telescope up in L2 also (launching in 2027, nominal life 5 years).... ESA is launching an exoplanet-focused infrared scope to L2 in a similar timespan... Presumably other "smaller" infrared scopes will fly by 2042. So...
There's so many wavelengths and different possible space telescope missions. Let's not replace JWST (assuming it gets a normal mission life)-- let's keep some infrared capability and do something else.