The Telescopes at the Grove Creek Observatory

                      Short Summary: (click links to go direct to each telescope)

THE CELESTRON C-14" (36cm) SCHMIDT CASSEGRAIN
A very unique telescope with a unique history!
Celestron Pacific C14 Schmidt Cassegrain Telescope
Aperture: 36cm (14")  Focal Length: 3,910mm  Focal Ratio: f/11

Click here to watch a video about our C14

Light Path through a Schmidt Cassegrain Telescope

This is the most outstanding instrument at the Grove Creek Observatory. With a focal length of 3,910mm, this telescope is used for high resolution objects. Being a Schmidt Cassegrain, it provides a higher contrast than even larger Newtonian telescopes. The C14 was built in 1971 and was the second model made by the "Celestron Pacific" telescope company, using the original sturdy "sand-cast" rigid fork (with the original three paint scheme of white, grey and light blue tube). Its 36cm primary mirror is of an exceptional high optical standard - going beyond testing equipment that could measure an accuracy of 1/10 wavelength of light. The C14 can operate visually at f/11 or f/7 and can be configured with huge a variety of combinations for different types of astrophotography and CCD imaging. The was mounted on a home made 60kgs equatorial wedge, constructed from 23mm stainless steel plates. This was attached to our massive pier in the main dome, driven 6 metres into the ground and totally isolated with no part of the building touching it. The pier is 50cm in diameter and constructed with a solid steel core of 18cm diameter, surrounded by concrete, sealed with a large gas pipe on the outside.

The C14 at Grove Creek has its own fame, as many live astronomical events were recorded with special video cameras attached, including live images of the Shoemaker-Levy Comet hitting Jupiter in July 1994, that were shown via a live satellite feed throughout the world on Australian and international TV, including CNN, the BBC and Channel 7. Well over 10,000 people viewed Halley's Comet through this telescope when it was installed at Grove Creek in 1985. Many professional and amateur astronomers that visited Grove Creek, when we used to run public tours, often commented on how amazing the optics of this telescope was. 

In 1998, extensive electrical upgrades were made by Steven Williams and Christopher Ralph, to replace the old original Right Ascension AC clock tracking and DC slewing motor (abbrev. "RA" - the east/west movement) and the DC Declination motor (abbrev. "DEC" - the north/south movement) with a home-made Z-80 processor controlled stepping motor control system. For the first time on such an old mount, high magnification "auto-guiding" astrophotography and the early days of astronomical CCD imaging was then made possible with this system. The periodical error of the mount was only 8 arc seconds, which was remarkable, considering its age and that it was never designed for such a role. Along with the electronic tracking upgrades, a Celestron Astro-Master computerised digital setting circle was also installed, to make finding objects a breeze. An innovation that was never even dreamed of, when the mount was designed in the late 60's! Previously, tedious sightings had to be read from old mechanical setting circles attached to the mount. Grove Creek was one of the first observatories to purchase a SBIG ST-4 CCD autoguider and stunning film photos were achieved as a result.

Then two disasters struck... In 1999, one of the most severe storms ever seen in the area totally blew the entire 300kgs dome off its rails, driving it into the telescope's mount and destroyed the delicate RA gearing system and mounting hardware for the optical encoders. However, even with such amazing force, the optics of this ruggedly built telescope didn't even loose collimation! Fortunately (and very generously) Celestron, understanding that this particular telescope was of special vintage, re-built the RA gear system at no charge and the dome was modified so such an horrible incident could never happen again. However, to the complete dread of everyone involved with Grove Creek, a violent electrical strike directly hit the C14 in 2002, which not only caused massive damage to most of the electrical devices and appliances throughout the observatory but totally destroyed both the home-made drive controller, Astro-Master and optical encoders!  Parts for the previous home-made drive system were no longer available, so it was replaced with a third-party commercial computerised duel stepping motor drive system. The Celestron Astro-Master was replaced with a Argo Navis digital setting circle computer, with RS2-232 planetarium control functions from Wildcard Innovations from 2002 until 2008.

As Grove Creek closed to public tours in September, 2007, the C14 was able to be configured as a dedicated CCD imaging internet remote controlled instrument. Therefore, In May 2008, the C14 was removed from the dome and installed on a Astro-Physics GTO-1200 mount and pier, in our new robotic sliding roof Middle Observatory. This enabled us to put it online on the internet for everyone to use.

This telescope is owned by Steven Williams and is used as a personal viewing instrument at Grove Creek, as most of the other telescopes are dedicated CCD imaging instruments only. This telescope is currently installed in the main dome and is a non-modified "classic" model. In January 2009, a special pier adaptor plate was installed to enable a LX-200 Wedge base, Paramount ME mount or a Astro-Physics Mount, as the previous C14 was moved into the Middle Observatory in May 2008. A CCD camera for personal use can be easily installed, operated from a PC in the control room (see right image).

20cm (8") f/7 Newtonian Telescope:
  
 (Mounted on  "Samson" Equatorial Mount LEFT, Sturdy wooden Dobson Mount RIGHT)

The 8" (20cm) f/7 Newtonian telescope provides a nice contrast and compliments the larger telescopes at Grove Creek. Being one of the most common type and size of a serious amateur telescope, this telescope is provided as a "learning tool" for visitors at Grove Creek, who may be thinking of starting the hobby of astronomy and what they can expect from a (comparably affordable) and portable instrument. This telescope can be placed on an German Equatorial Mount (which tracks the movements of stars) or on a common Dobson Mount, to enable those people that are not used to a telescope, to just roam the skies with. A telescope like this with a Dobson (non-tracking) mount, is a good "starter telescope" and simple models can start from around AUD$700, without accessories. The equatorial mount shown is known as a "Samson Mount" are no longer made any more but used to be a very popular mount available from Astro Optical, in Sydney, Australia. Please note that despite the many offers we receive via email, this mount is NOT for sale at any price, as it has a suburb low periodical error and is owned by Jim Lynch.

Small Radio Telescope:

The Small Radio Telescope (S.R.T) uses a 2.3m diameter dish driven by an altitude/azimuth computer control drive system with an FFT based radio spectrometer receiver operating between 1370 - 1800 MHz to make various radio astronomy observations including the 21 cm (1420 MHz) spin flip line of atomic hydrogen. The receiver uses digital technology with a 8-bit analogue to digital down converter, digital signal processor (DSP) and is controlled remotely using a STAMP microprocessor and RS-232 communications. Projects are submitted by users in the astronomical community, where the resulting data is passed on over the internet for further study.

Jove Riometer:

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