In article .com,
wrote:
As a thought - if you placed your Hydrogen tank in a lunar polar
crater, and put MLI between it and the surface, but had no insulation
where the tank could only see black space - what would that do to the
cooling requirements.

It would help considerably, but wouldn't be a full solution. MLI is good
but not magic (and the tank supports have to be more solid than MLI!),
and there's still a moderately warm Moon filling the lower hemisphere.
(Insulating the tank from the surface also insulates the surface from the
sky, and it will warm up. There is heat flow from the Moon's interior.)

Likewise, a hydrogen tank in Earth Orbit, with three disks of MLI. One
of these blots out the sun, one the Earth, and the other the moon. The
MLI discs are some way from the tank, so that only a small part of the
IR they emit will hit the tank.

It gets more complicated than that, because -- for example -- the tank
side of the Earth-blocking disk has to be shaded from the Sun as well
as the Earth. Not impossible, but complicated.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |