Ntil the last few decades
Not Much Could Be Done much could be done improve resolution because atmospheric turbulence was the most important cause of lower resolution but light athering could be increased by making larger mirrors The new techniue of making mirrors out of separate segments has allowed for much larger mirrors a techniue made practical by the concurrent development of computers to keep these segments properly aligned Further the techniue of adaptive optics in which the shape of the overall mirror is adjusted to keep the image of a
Guide Star Or Of Laser star or of laser reflected off of sodium atoms in the out atmosphere sharp has I Was A Stranger greatly improved forround sodium atoms in the out atmosphere sharp has reatly improved for round telescopes In addition putting telescopes into orbit also avoids the problem of atmospheric factors reducing resolution The adaptive optics techniues were originially developed for spy satellites and were de. The humblest backyard setup to state of the art observatories to the Hubble Space Telescope and spy satellites Chapters describe the development design and operation of telescopes; how observatories are sited engineered and built; variations such as solar and liuid mirror telescopes; and some of the key astronomical discoveries telescopes have made possible And there are plenty of surprises along the way We learn for example that most of today's professional astronomers never even look through their own telescopes relying instead on digital imaging measurement and analysis or even re. ,
Classified in the early 1990s to the benefit of astronomers The author mainly discusses astronomical telescopes but also describes the physics behind spy satellites and lidar Lidar is a remote sensing techniue analagous to radar but using laser pulses rather than radio or microwaves It can be used to make extremely accurate topographical maps and can also be used to detect wind shear a useful thing to know around airports as arriving and departing planes are very vulnerable to sudden severe usts As the receiving device for lidar is a telescope there is a connection to the main topic In terms telescope there is
a connection to the main topic In terms instruments used in conjunctionconnection to the main topic In terms instruments used in conjunction telescopes the author describes such imaging techniues as photographic imulsions mostly out of date now digital devices like CCD similar to a digital camera specrometry and inferometry The author keeps the euations to a minimum. Mote computer control of a night shrouded observatory on the other side of the Earth But as The Telescope explains these magnificent instruments do than simply peer into space They project and receive laser beams for communicating mapping and making detailed
Observations Of The Earth Theyof the Earth They look down at us from spy satellites providing secret images to intelligence agencies and increasingly iving a curious public access to pedestrian images The Telescope is the ideal introduction to a fascinating instrument that has taught us so much but that most of us know so little about Scienc.