Palomar telescope

Casting is usually restricted to two types of operations. The first involves the simple pouring of molten glass into molds. Examples include such massive shapes ns the borosilicale minor blank for the Ml. Palomar telescope and the large glass-ceramic mirror blanks for observatories in Australia and South America. The molds are specially constructed for refractory materials. 

Modem reflecting telescopes range in size from small amateur instruments to the great Palomar telescope with its mirror measuring 200 inches across, but the principle is the same. Parallel rays of light from the stars are reflected to a single focal point by a parabolic mirror. 

Casting or molding has produced, for example, the 20-inch-thick Palomar telescope mirror and the submilli-... 

R. Florence, The Perfect Machine Building the Palomar Telescope, Harper Perennial, 1994, p. 384. 

Evolution in telescope making since the Palomar has not been limited to the area of optical production. The alt-azimuthal mount has become the established solution since the Bolshoi 6 m telescope, for its superior mechanical performance and the compact, cost-efficient enclosure design it allows. Better understanding of the properties of atmospheric turbulence allowed a more accurate characterization of a telescope properties, a more balanced approach towards specifications and error budgeting and a better understanding of the utmost importance of site selection. Any ground-based telescope of appreciable size will be primarily limited by the effect of atmospheric turbulence, not to mention the proportion of photometric nights allowed by weather conditions. 

In Helen Wright Palomar The World s Largest Telescope Origin of the Telescope (p. 9)... 

Wright, Helen. Palomar The World s Largest Telescope. The Macmillan Company, New York. 1952. 

Astronomer George Ellery Hale (1868-1938), educated at MIT, founded Mt. Wilson observatory, 1904, and designed the two-hundred inch (five m) reflecting telescope for Mt. Palomar observatory. 

The study of the structure and chemical composition of the universe proceeds today at an increasing tempo. There is more work to be done than our telescopes can handle. Research projects, for example, are programmed on a tight schedule for in advance for Mt. Palomar s great telescope with its 200-inch reflecting mirror. 

Lenses have been made using glass since microscopes and telescopes were first invented. When visible light is used, this is still generally the case. For transmitted light, the challenge is usually to minimize absorption some telescopes, such as that on Moimt Palomar, use a very wide coated glass reflector. The critical factor is now not transmission but thermal expansion. 

Hale Telescope, Palomar Observatory, California 5 3.3 Equatorial horseshoe yoke... 

Fig. 1. Gontoui plots of VV114 in the optical (B) and the near-in aied K). North is up and east to the left. The B image was taken by Dave Sanders on the Palomar 1.5 m telescope (see also Scoville et al. (1989). The origins of the plots are defined by the brightest 2.2 t/xa (source A) knot whose position is determined to be aisso = 0l 05 19 .82, 1960 = —17°46 25"7. The main IR sources of interest are denoted, in decreasing order of K flux, by the letters A,B,C and D.

Abstract, bi a joint effort between engineers and scientists at the Jet Propulsion Laboratory and the California Institute of Tedinology, a near-in ared (0.8 - 2.6 on) direct imaging system has been developed and integrated into the Caltedi Palomar Observatory detector series. The camera system has been tested and operated in a science mode at the prime-focus (f/3.3) of the Hale 5-m Telescope. This paper outlines the system components and performance, including discussion of the detector linearity. 

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