On one had, it makes the air so thin and bereft of humidity that it is the ideal location for terrestrial telescopes
, allowing us, Guzman remarks, to "read the vast open book of memory, page by page.
and Hubble allow us to see some 13 billion years back in time.
Existing ground data is of poor quality or is non-existant because atmospheric water vapor absorbs most radiation before it reaches terrestrial telescopes
The explosion took place in a galaxy some 5 billion light-years from Earth, meaning that light from the supernova took 5 billion years to reach terrestrial telescopes
cannot resolve the light echoes of distant supernovas, says Schaefer, but two fairly close novas have exhibited the effect, Nova Persei 1901 and Nova Sagittarii 1936.
This is the same kind of erecting system used in terrestrial telescopes
and rifle scopes.