richmond@astroplasma.berkeley.edu (Michael Richmond) (07/25/89)
As to why HST only has 1200 hours of observing time in its first year: I'm not sure whether that figure includes several months of testing, but one thing I did learn recently is that, on those occasions when an observation is being made for more than one half-orbital period (45 minutes), the telescope is left pointing at the object - and hence looking at the EARTH - for another 45 minutes, until the object comes back out from behind the Earth. It seems that it's more practical (timewise? propellent-wise?) to leave the telescope where it is pointing than to move it to another object for a short time, then go back and re-acquire the first one. I'd be glad to learn that I am mistaken - can anyone tell us more about this "feature" of ST? I realize that you lose a lot of observing time being in LEO, and that it really needs to be there, but ... Oh well, I imagine that probably only a small number of ST observations are being made this way; most are probably less than 45 minutes long. -- Michael Richmond "This is the heart that broke my finger." richmond@bllac.berkeley.edu
yamauchi@cs.rochester.edu (Brian Yamauchi) (07/25/89)
In article <26623@agate.BERKELEY.EDU> richmond@astroplasma.berkeley.edu.UUCP (Michael Richmond) writes: > >I realize that you lose a lot >of observing time being in LEO, and that it really needs to be >there, but ... Why does it really need to be LEO? Why not put it in a higher orbit? _______________________________________________________________________________ Brian Yamauchi University of Rochester yamauchi@cs.rochester.edu Computer Science Department _______________________________________________________________________________