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41 " Ritchey-Chrétien Telescope Mirror Sold!

Price - $95,000.00

Ad Number: 47778

Posted: 26 Feb 2015

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One meter telescopes are very much in demand to study Earth crossing comets, asteroids, meteors and other objects that might impact the Earth.
These 41" Ritchey-Chretien telescope optics present a unique opportunity to add an important instrument to the scientific community.
This picture shows the 41" mirror supported by a Kevlar insert (shown in green). The Kevlar is stronger than steel and is much lighter than steel.
This insert supports the total weight of the mirror and is bolted to a 3/4" aluminum plate, which in turn would be bolted to the bottom tube assembly.

Because the mirror is tapered, no floatation support is required.
Unlike any metal support, Kevlar has a very low thermal expansion, making it ideal as a rigid support for this 480-lb. low expansion mirror.
The insert and aluminum plate has been completely machined and is included as a part of the mirror assembly.
One meter, 3 science package telescope optics set

Edward R. Byers Co. is offering the following one meter class telescope mirror set:

Optical configuration: Cassegrain
Optics design: Ritchey Chretien F-13.2
Primary diameter: 41 inches

This optics set is unique as it can support 3 separate science packages..!
Typical science packages can be, but is not limited to visible spectrum, Infra-red and spectroscopy, both visible and infrared.

The truss is designed to support two science packages mounted inside the elevation axis bearing hubs, each with an available clear inner diameter of 8 inches. The rotatable tertiary diagonal selects one of these positions. Removal of the diagonal allows the converging light cone to focus approximately on axis and just forward of the primary surface supporting the third science package up to 8 inched diameter.

Removal of the diagonal is performed easily by use of a permanent gantry hoist integral to the optical truss assembly that also safely stores it from damage and contamination.

Supporting engineering designs and fabrication:
This project was started by John Gregory but never completed. John and his wife were taken in an automobile accident and the project was mothballed. Edward Buyers became owner of the present equipment,

The following people have been and still are involved and available for completion of this project and are listed below:

Edward Byers: Equipment owner, including gear drives
Mike Jones: Field corrector design and manufacture
David Windisch: Truss design, manufacture assembly, system alignment
Sidereal Technologies: Drive electronics

This beautiful 41-inch Ritchey telescope mirror, with Cassegrain secondary and Tertiary mirrors, makes up a complete optical system. This is a rare find. The 41-inch primary is made of Zerodur. The Cassegrain and Tertiary mirrors are made of Quartz (fused silica). This optical system was a life-long dream of the famous optical engineer, John Gregory. For those who may be contemplating the construction of a world-class, research observatory telescope, either for private use, or a teaching instrument for a college or university, Byers is available to offer additional assistance in design manufacturing of a fully functional instrument.
Comments from Mike I. Jones optical engineer:
“Yes, good old John Gregory and his wife Carolyn died in a car accident in November of 2009. John had wonderful plans for these mirrors, and would be happily viewing through them by now if he were still alive. The mirrors were made by an optical shop in Arizona, and these are the final fabricated values for the three mirrors John obtained from the shop. OSLO file of actual fabricated values is attached.
Though the conical primary is perforated, John chose to mount it on an altazimuth mount with Nasmyth focus. He had a flat tertiary made to fold the light out ahead of the primary and along the elevation axis. As I recall the diagonal tertiary mirror has a 7" minor axis. It also has roughly a 1/2" hole cored through it to facilitate laser alignment.
I designed a 3-element broadband field corrector for this mirror set that John planned to build after he got the basic instrument up and running. It gives <0.5 arc-second imagery over the 0.38-0.95µm spectral band over a 7" diameter truly flat field. I can post that design sometime if anyone that buys the mirror set is interested.”
-Mike Jones

Contact Ed Byers for details


  • Condition NEW
  • Location Barstow, CA

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