Please note the following quotes from this Web page:

http://www.coseti.org/hst-jwst.htm

The atmospheric transmission chart presented here covers the approximate wavelength range of the James-Webb Space Telescope. Not shown is the ultra-violet band between 0.3 microns and 0.1 microns which is blocked by Earth's atmosphere but is available to the Hubble Space Telescope. These two telescopes together provide a complementary means to access a substantial and contiguous range of optical frequencies.

Hubble's mirror system is usable over the wavelength range of approximately 110 nm to 1100 nm. The present specifications for the James Webb mirror system calls for a response over the wavelength band of 600 nm to > 10,000 nm. The extended spectral range in the ultra-violet for the Hubble Space Telescope and the extended infrared range for the James Webb Space Telescope, opens up a much larger window for Continuous Wave (CW) and Pulsed-Type OSETI than is possible for ground-based observatories.