ASTRONOMICAL RESEARCH INSTITUTE

ASTRONOMICAL RESEARCH OBSERVATORY

0.61m  -  24 Inch Telescope 

The Astro-Research 24 inch carbon fiber OTA on a SB Paramount ME

Paramount ME - Astro-Research 24" OTA - Installed May 2007

First light image 24 inch telescope M87 - May 8th 2007

 These images were taken with 12 - 16 mph winds, a testament to the rigidity of the Paramount ME working at full capacity.  Light cirrus clouds no moon.  Exposure time - 180 seconds.  See magnitude measures.

24 inch telescope image of M51 - 180 seconds

24 inch telescope image -  M 13 - 300 second image. 

Note at the lower left is galaxy IC 4617 at magnitude 16.0 Blue

We work on research images at ARI so none of the images were taken with filters to produce color.  Note that there is slight elongation of the star images due to wind.   Exposure time - 180 Seconds

Our quest was to place the largest telescope possible on the current Software Bisque Paramount ME that was located in Astronomical Research Observatory I.  The design, is a 24 inch ( 0.60m ) astrograph that is similar to the 32 inch telescope we designed and built previously.  As an astrograph, the camera operates at the prime focus, so no secondary mirror is used.  This eliminates an additional optical surface which may introduce errors and eliminates light loss due to absorption by an additional optical component.  The difference on this project compared to the 32 inch telescope is the use of light weight carbon fiber technology to create an optical tube assembly that weighs less than 150 lbs.   With extensive use of carbon fiber and aluminum tubing, this allowed us to produce a telescope that weigh only 143 pounds (65 kilograms).  This is 7 lbs less than the design weight limitation of the SB Paramount ME.   Truss tubes, mirror cell, and camera mount were all made using carbon fiber to reduce weight.  Our secondary goal was to eliminate nearly all the expansion and contraction problems associated with focusing using metallic truss tubes.  No data has been obtained yet for variations in focus based on the expansion coefficient of the carbon fiber truss tubes.  Analysis of the structural properties of carbon fiber truss tubes were quite surprising with better than 30 arc/sec of  total flexure in the optical tube assembly when in use.   The primary mirror is Pyrex 24 inches ( 0.60m ) in diameter, 1.6 inches thick, figured to better than 1/16 wave with a total weight of just 59 pounds ( 26.82 kg) to keep the overall optical tube assembly light weight.  

We have commissioned our latest instrument, a 24 inch ( 0.60m ) which resides on a Software Bisque Paramount ME.   The Astronomical Research Observatory (ARO) was constructed for the purpose of operating sky survey telescopes to be used in Near Earth Object Observations, asteroid,  supernova and AGN research that could be used in Astronomical Research Institute education and public outreach programs.  The CCD camera is a Santa Barbara Instruments Group STL 1001E with 24 micron pixels and a 1024x1024 array.  The telescope and CCD camera are controlled using Software Bisque software including The Sky Professional, CCD-Soft, Orchestrate, and T-Point.   

Image scale for the Astro-Research 24 inch is 1.59 arc/sec per pixel with a field of view that is 27.20 x 27.20 arc minutes.  Focal length is 122.2 inches ( 3105mm ) at f/5.17 using a Televue STL-ParaCorr.   Limiting magnitude with this telescope is expected to be unfiltered magnitude 20.4 with a 60 second exposure.  

The retractable roof design suited our current needs better than a dome for full access to the sky without dome rotation problems.  In addition, it was more economical allowing us to place our funds into telescopes and CCD imaging devices rather than buildings to house our equipment.    The current Paramount -  Astro-Research 24 inch telescope will operate in the observatory conducting NEO observations and supernova research.

Carbon fiber mirror cell components and aluminum (red) tail ring.  Carbon fiber truss tubes can be seen in the out edges of the tail ring.  All hardware is stainless steel.

Carbon Fiber 24 inch telescope ( 0.60m ) Components

carbon fiber truss tubes, mirror cell triangle, camera mount baffle tube

For information regarding Mike Lockwood's optical fabrication -  see Lockwood Custom Optics.

24 inch Instrumentation Design

Design Analysis For the Astro-Research (0.61 meter) 24" f/5.32 Telescope

Other first night images and data.

24 inch telescope M 100 Exposure - 180 Seconds

M87 first light image - Limiting magnitude 21.1 in a 180 second exposure.  Reference above is a 20.6 magnitude star based on 290 photometric reference stars and image has been flipped for astrometry and photometry.  Above image has been enlarged 200% to show detail.  Additional data below.