01-16-2004, 09:00 PM
Hi,
Many observations take time. Presently, about eight hours is the longest uninterrupted observation that can be made on Earth (low angle observations are bad because at low angles one is looking through more of the atmosphere). Once an observation is interrupted, it is can be difficult to impossible to resume it because of the extreme pointing accuracy required (a single error is just a baseline shift that can be compensated for, multiple errors would cause interference phenomena that can completely swamp the data).
Astronomical observations are all about gathering light without losing clarity to artifacts. More light is gathered by increasing the size of the mirror or by increasing the length of the observation. We are at pretty near the limit of both of these in Earth based observatories. A bigger space based telescope would be a major help, but unless a way is found of manufacturing the optics in space, it is not likely. The Moon is the best bet we have of improving astronomical observations in a reasonable manner.
--Pete
Many observations take time. Presently, about eight hours is the longest uninterrupted observation that can be made on Earth (low angle observations are bad because at low angles one is looking through more of the atmosphere). Once an observation is interrupted, it is can be difficult to impossible to resume it because of the extreme pointing accuracy required (a single error is just a baseline shift that can be compensated for, multiple errors would cause interference phenomena that can completely swamp the data).
Astronomical observations are all about gathering light without losing clarity to artifacts. More light is gathered by increasing the size of the mirror or by increasing the length of the observation. We are at pretty near the limit of both of these in Earth based observatories. A bigger space based telescope would be a major help, but unless a way is found of manufacturing the optics in space, it is not likely. The Moon is the best bet we have of improving astronomical observations in a reasonable manner.
--Pete
How big was the aquarium in Noah's ark?