RitcheyTelescope.jpg(623 × 480 píxels, mida del fitxer: 161 Ko, tipus MIME: image/jpeg)

Descripció a Commons
Descripció
English: Ritchey 24" reflective telescope

This picture was taken in July 2004 from an exhibition at Chabot Space & Science Center in Oakland, California.

The caption of the exhibit said:

Ritchey 24-inch Reflecting Telescope
By George W. Ritchey, American Telescope Maker
On loan from Smithsonian Institution
George Willis Ritchey (1864-1945) was the builder of the first successful large American reflecting telescopes. A telescope designer who perfected the methods for making astronomical mirrors and a master at celestial photography, George Ritchey worked closely with George Ellery Hale, the phenomenal fund-raiser and organizer of observatories. Mount Wilson Observatory with its 60-inch and 100-inch reflector telescopes stands today as a monument of their collaboration.

The first important telescope built by George Ritchey (at Yerkes Observatiory in Wisconsin) was the 24-inch reflector you see here. He made the primary mirror (an f/4 hyperboloid) in his shop and Francis G. Pease worked on the cassegrain secondary mirror. Ritchey later photographed many nebulae with this telescope. The pictures were the first opportunity astronomers had to see the true forms and complicated structure of nebulae like the Orion Nebula. But more importantly, the photographs convinced astronomers that reflectors would be the large telescopes on which future research would be based.

The telescope is on a German equatorial mount. The mirror is silvered glass 23.5 inches wide by 2 and 5/8 inches thick. The bottom of the mirror is supported at three points and at the edge. The skeleton tube, 7 feet long, held the secondary mirror and photographic accessories. The eyepiece position has an elaborate stage (brass) with a 2 and 1/8 inch threaded opening. The entire stage can be rotated as well as moved precisedly in either axis.

The holder is designed for use with a photographic plate. The drive mechanism (in the .... <the rest of the text were hidden from view>

Data 15 de juliol de 2004 (original upload date)
Font Treball propi
Autor Kowloonese de la Viquipèdia en anglès

Llicència

Public domain Jo, el titular del copyright d'aquesta obra, l'allibero al domini públic. Això s'aplica a tot el món.
En alguns països això pot no ser legalment possible, en tal cas:
Jo faig concessió a tothom del dret d'usar aquesta obra per a qualsevol propòsit, sense cap condició llevat d'aquelles requerides per la llei.

Registre original de càrregues

La pàgina de descripció original era aquí. Els noms d'usuari a continuació es refereixen a en.wikipedia.
  • 2004-07-15 20:33 Kowloonese 623×480× (165136 bytes) Ritchey 24" reflective telescope

Llegendes

Afegeix una explicació d'una línia del que representa aquest fitxer

Elements representats en aquest fitxer

representa l'entitat

Historial del fitxer

Cliqueu una data/hora per veure el fitxer tal com era aleshores.

Data/horaMiniaturaDimensionsUsuari/aComentari
actual20:55, 23 jul 2009Miniatura per a la versió del 20:55, 23 jul 2009623 × 480 (161 Ko)Toontje{{Information |Description=Ritchey-Chrétien telescope |Source=en Wikipedia |Date=15. Juli 2004 |Author=Kowloonese |Permission=Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Ve

Les 2 pàgines següents utilitzen aquest fitxer:

Ús global del fitxer

Utilització d'aquest fitxer en altres wikis:

Metadades