How can we say JWST is the after Hubble space telescope generation if its angular resolution is same as former

Question

yea good point campbell, but how can it's angular resolution be the same as HST even though it's collection area is 6 times larger as lindajun said?

Answer 1

perhaps because angular resolution is not the only parameter of interest? there's also spectral range and magnifying power for instance. I've read somewhere (wikipedia?) that JWST should be able to detect more distant objects than hubble can.

Answer 2

Although JWST has a planned mass half that of the Hubble, its primary mirror (a 6.5 meter diameter beryllium reflector) has a collecting area which is almost 6 times larger.

Hubble:

Collecting area approx. 4.5 square m

Focal length 57.6 m

JWST:

Collecting area 25 square m

Focal length 131.4 m

Answer 3

JWST works at longer wavelengths (deeper into the infrared) than Hubble, so it has about the same resolution even though it's bigger.  The longer wavelengths and larger collecting area will bring big improvements.  Also, it will operate in a darker environment.

Answer 4

After means later, not better. It will be launched after Hubble is too old to use any more.