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Grasslands Observatory : Operations


 
At the gate looking south to the Observatory Looking north from the observatory during the day
       
Grasslands Observatory from the west
Grasslands Observatory from the west - March 2017
 
Grasslands Observatory from the South Earth's shadow February 23, 2017
Grasslands Observatory from the south - March 2017 Earth's shadow and observatory buildings - February 23, 2017
   
Old 24-inch telescope Old 24-inch telescope circa 2005
Old 24-inch telescope and old Warm Room circa 2000 Old 24-inch telescope circa 2005
 
CCDCamera.jpg (45315 bytes) Camea Close-up.jpg (47952 bytes)
Dream Machine CCD camera
   
Milky Way rising at the old Grasslands Observatory
Night at the old Grasslands Observatory
   
New Warm Room/Control Room circa 2014 Entrance to new Warm Room/Control Room
New Warm Room/Control Room with old Observatory Building circa 2014 Entrance to new Warm Room circa 2014
   
Storage Room Inside the Warm Room June 2014
Warm Room/Control Room and Storage Room Inside the Warm Room June 2014
   
PlaneWave CDK 24-inch telescope PlaneWave CDK24 24-inch telescope
PlaneWave CDK24 24-inch f/6.5 telescope during the day
 
PlaneWave CDK 24-inch f/6.5 telescope at night TPO RC 16-inch f/8 telescope
PlaneWave CDK24 24-inch f/6.5 telescope at night TPO RC 16-inch f/8 telescope on AstroPhysics 1600GTO mount
   
Wi-Power antenna Wi-Power antenna and Warm Room
Wi-Power antenna Wi-Power antenna and Warm Room
       
 
Earth's Shadow Summer Milky Way overhead Achernar Achernar culminatiing on December 10, 2014
Earth's shadow at sunset April 6, 2013 Late August early evening overhead Milky Way Achernar culminating on the Southern Horizon 4 November 2005, 11:20 pm MST; Altitude 1 deg, Azimuth 182 deg; Magnitude 0.54 Achernar culminating on the Southern Horizon December 10, 2014 at 8:45 pm MST
       
Gacrux Space alien Suns rays Owl on All Sky Camera
Gacrux (the top star in the Southern Cross) culminating on the Southern Horizon 18 May 2007 9:40 pm MST; Altitude 0.5 deg, Azimuth 184 deg; Magnitude 1.65 Space alien? Probably Western Meadowlark sitting on All Sky Camera All Sky Camera view of Sun's rays shining through clouds Another space alien? Probably an owl sitting on the All Sky Camera
       
Sun Halo Moon Halo on January 18, 2016 Moon halo January 19, 2016 Winter Milky and Zodiacal Light
Sun halo on January 18, 2016 at 11:51 am MST Moon halo on January 18, 2016 at 8:46 pm MST Moon halo on January 19, 2016 at 8:11 pm MST Winter Milky Way the Zodiacal Light on February 29, 2016
       
Moon halo on the evening of January 4, 2017 Moon halo on February 3, 2017    
Moon halo on January 4, 2017 at 7:56 pm MST Moon halo on February 3, 2017 at 7:21 pm MST    
       

 

The Grasslands Observatory is owned by Tim Hunter. The Director of the observatory is James McGaha. The observatory was started in 1985 when Tim Hunter purchased 20 acres of land at a remote location in Southeastern Arizona approximately an hour's drive from Tucson. The site has no horizon obstructions in any direction and sits on a large grassy plateau surrounded by distant mountains. It is at 5000 feet elevation, and there is only minor/moderate light pollution from distant Tucson, Sierra Vista, and Nogales, Arizona (and Sonora, Mexico).

In 1986, a 24-inch f/5 equatorial Newtonian (f/20 Cassegrain telescope) was purchased from its builder Jeff Shaffer and installed in a 20 x 20 foot roll-off building. The original Observatory Building was designed by Tim Hunter and James McGaha and built by them under the guidance of Jeff Shaffer. James McGaha coordinated the moving and installation of the telescope in its new facility.

The original Observatory Building consists of a 20 x 20 foot roll-off roof structure housing the fork mounted 24-inch f/5 Newtonian reflector. To the direct west of the old Observatory Building is the Warm Room (also known as the Control Room), a separate building which is heated and insulated. It contains the controls for the original 24-inch telescope and also has a microwave, refrigerator, computers, a bed, power, and telephone. Unfortunately, there is no running water.

Since 1995, the original 24-inch f/5 telescope and its associated instruments as well as new telescopes in new observatory buildings have been operated from the Warm Room/Control Room. The Warm Room was built in 1995 when the original 24-inch telescope was changed from mainly visual use to electronic imaging at the Newtonian f/5 focus.

The Warm Room (also sometimes called the Control Room) was originally a small, 14 x 14 foot one-room well insulated house with lights, heat!!, a refrigerator, microwave, futon, chairs, and a Control Console for operating the original 24-inch telescope. The Control Console even today remains connected by cables running through a metal conduit to the Original Observatory Building. Now the Control Console is also connected to three other separate observatory buildings (ASA 20-inch Building; PlaneWave CKD24 Building; TPO RC 16-inch Building) by CAT6 ethernet cables to control computers in each of those buildings.

In late 2013 and early 2014, the Warm Room/Control Room was significantly expanded to the west so that it now measures 14 x 26 feet (outside dimensions). The windows were removed, and the door situated to the south out of the path of the main wind direction. A heavy duty door with a heavy duty screen was installed.

Added to the expanded Warm Room is a large separate Storage Room for infrequently used tools and spare equipment. Most of the large accumulated tools and equipment (such as fence post driver, fence posts, pickaxe, spare wood beams, and tarps) were removed from the old Observatory Building and placed in the Storage Room vastly improving the look and cleanliness in the old Observatory Building itself. A new weather station and an All Sky Cam were also added.

The Observatory has had reliable internet service since the summer of 2015. This is provided by TransWorld Network Corp (TWN) using its Wi-Power Business Connect. In order to obtain a signal from the TWN transmitter sitting more than 20 miles to west on a small mountain, it was necessary to have Sulpher Springs Valley Electric Cooperative, Inc (SSVEC) install a 45-foot power pole. A Wi-Power antenna was then placed about 30 feet off the ground, high enough to clear a small ridge line to the west and high enough to receive a strong signal from the Wi-Power transmitter.

The three new 14 x 14 foot roll-off roof observatory buildings lie to the south and somewhat west of the Original Observatory Building and the Warm Room. The eastern most of these is Buiding 1 which contains an ASA 20-inch f/3.5 astrograph which went into operation in early November 2017 and is controlled remotely. It is used with an FLI Proline 9000 CCD and FLI CFW5-7 filter wheel with a clear filter and photometric R, V, and B, filters, and a hydrogen alpha filter.

Building 2 is the center 14 x 14 foot roll-off roof observatory building. It contains a PlaneWave CDK24 24-inch f/6.5 telescope with an FLI Proline 9000 CCD and FLI CFW5-7 filter wheel having a clear filter, a hydrogen alpha filter, and photometric R, V, and B filters. This telescope is in operation and is controlled remotedly.

Building 3 is the western most 14 x 14 foot roll-off roof observatory building. It contains a TPO RC 16-inch f/8 telescope with an FLI Proline E2V and an FLI CFW1-8 filter wheel containing a luminance filter, a hydrogen alpha filter, an Oiii filter, an Sii filter, and standard photometric R, V, B, and I filters. This telescope is in operation and is controlled remotely.

Ancillary equipment includes an 8-inch f/4 Meade LXD75 Schmidt-Newtonian telescope which has been mounted onto the side of the original 24-inch telescope. Imaging through the 8-inch telescope is done with a Canon 20Da or 60Da digital camera back.  In addition, a Takahashi Epsilon f/2.8 180 Astrograph is available for use.

 

Imaging at the Grasslands Observatory

From 1987 until approximately 1995 film was used for all astrophotography. Some of the early film images are still on the website (see photographic Messier Marathon). From 1995 onward only digital imaging has been performed. The main workhorse digital cameras until 2014 were the Apogee AP7 and the Fingers Lake Instrumentation Dream Machine CCD on the original 24-inch telescope using its Newtonian focus at f/5.

Many of the images from the AP7 or Dream Machine remain on this website. Quite a few of the images are mediocre, more due to poor imaging conditions or poor processing of the images rather than any limitations with the equipment. Some of the images from the AP7 and Dream Machine are quite good and difficult to improve upon using the new CCD's and telescopes now availabe at the Observatory.

The Apogee AP7 CCD camera was used until September 2000. It had a very sensitive SITe 512 x 512 chip with 24 micron pixels. It was attached to an ISIS FW1 filter wheel containing an open slot, a clear filter, and standard R, V, B, and I (near-infrared) photometric filters. Among its accomplishments was the obtaining of black and whites images for all 338 Arp Galaxies and tri-color imaging of all the Messier Objects. In September 2000, the AP7 camera was replaced by the Dream Machine which was in operation until late 2014.

The majority of the images presently on this website were obtained with the Dream Machine combined with a Finger Lakes CFW-1 Color Filter Wheel using photometric R, V, and B filters as well as a clear (C) parfocal filter. The AP7 gave a field of view of 14 minutes. The Dream Machine has a chip with a similar quantum efficiency as the AP7, but the chip is twice as large (1024 x 1024) and gave a nearly 28 minute field of view with the 24-inch f/5 telescope.

Prior to the AP7, an HPC-1 camera had been used, and a few of its images are still posted on this website. The HPC-1 was a very fine camera with 12 micron pixels and a 1024 x 1024 pixel array. Its quantum efficiency was good in the red and green portions of the spectrum, but it had a relatively low quantum efficiency in the blue portion of the spectrum.

At the present time all imaging is done remotely using the PlaneWave CDK24 24-inch f/6.5 telescope and FLI Proline 9000 CCD or the TPO RC 16-inch f/8 telescope and the QSI 532 CCD. Either on-site or remote imaging with the Takahashi Epsilon 180 f/2.8 telescope and the Canon 60Da camera is also sometimes done.

Almost all of the images on this website are displayed with the north to the top and east to the left, standard astronomical orientation. This is to provide consistency in image display and orientation from object to object and from year to year.

 


tbh, Saturday 28 April 2007; revised 5 June 2014; revised Augus 28, 2014; revised Friday May 5, 2017; revised Sunday November 19, 2017.
 

 


Take Time to Smell the Flowers:
 

Flower.jpg (60781 bytes)
This wild flower was photographed at 1:20 am on 14 April 2001 by James McGaha with his then new digital camera. We noticed the wild flower as we were returning from a night's observing run. The flower grew alongside the dirt road going back to the observatory building. It was visible in our car headlights. The entire 20 acres of property at the Grasslands Observatory was covered by these flowers. Mike Newberry of Mirametrics, Inc. (Mira) writes: "The flower James photographed is Oenothera caespitosa, or "evening primrose". "Caespitose" means growing in clumps or tufts. The flower opens in evening twilight and withers in morning twilight, lasting only 1 night. Other flowers or flowers on other plants will open the next night. It grows at 3000 to 7500' elevation in gravelly places. About 20 species of Oenothera are in Arizona."

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