RAPTORS Satellite Hunting

Rapid Astronomical Pointing Telescopes for Optical Reflectance Spectroscopy (RAPTORS


The RAPTORS system was developed by five undergraduate engineering students at the University of Arizona as part of their senior design project during the 2016-2017 school year. The telescope was built with help from Starizona, a local small business and the AME machine shop on campus. Additionally, these students constructed this telescope at a fraction of the typical cost.

The primary objective of this system is to conduct a visible wavelength (0.4-0.9 µm) low resolution (R~30) spectroscopic survey of the objects in geostationary belt visible from Tucson, Arizona. The system consists of two identical 24-inch F/4 Newtonian optical tube assemblies with RAPTORS-1 dedicated to the GEO survey, and RAPTORS-2 dedicated for LEO observations (operational in 2018). RAPTORS-1 uses a Planewave HR200 Mount and is controlled using Sidereal Technologies SiTech software. The detector is an FLI Proline 16803 with a 4k x 4k 9 micron pixel chip. The combination yields a field of view of 52 x 52 arc minute with a pixel scale of 0.76”/pixel. The camera has a 10-position dual filter wheel with 50 mm square filters. The current compliment of filters include Sloan g’, r’ and i’ along with three transmission gratings from Richardson Gratings with resolution of 30, 35 and 75 lines per mm.

Nightly operations will be carried out autonomously using a Python script that controls the camera, focuser, telescope mount and the observatory roof. You can check the current weather status of the RAPTORS Nest Observatory.



Reddy Laboratory

Laboratory spectral characterization of space material enables us to accurately interpret remote sensing data. Space material include natural samples such as meteorites and artificial ones such as spacecraft parts. The Space Materials Analysis and Characterization (SMAC) at the Lunar and Planetary Laboratory investigates the spectral properties of space material over a wide wavelength range under space-like conditions.

Diagnostic absorption bands can be used as unique fingerprints to identify Remote Space Objects. The Reddy Laboratory is capable of acquiring spectra from 0.2-25 µm under high vacuum (10-7 Torr) and over a range of temperatures (50-500K) and phase angles (2-140 deg). The data from the lab are used to interpret ground-based spectra of asteroids, active satellites and debris; create calibrations to interpret data from spacecraft missions to planetary bodies.  

ASD Inc. Lab Spec 4 Hi-Res Analytical Instrument

"The LabSpec 4 Hi-Res analytical spectrometer is designed for analysis of materials that are characterized by sharp spectral features that may require more resolute spectral data for accurate detection and identification. The 3 nm VNIR, 6 nm SWIR spectral resolution of the LabSpec 4 Hi-Res analytical instrument provides superior performance across the 350-2500 nm spectral range. The enhanced spectral resolution in the SWIR range (1001- 2500 nm) is particularly useful for detecting and identifying compounds with narrow spectral features in these longer wavelengths such as soil mineralogy, pharmaceuticals, cosmetics, plastics and petrochemicals. Spectral data with 6 nm SWIR resolution provides a strong foundation for building accurate chemometric calibration models for quantitative and qualitative materials analysis. The spectrometer configuration delivers superior signal throughput and is compatible with all ASD bifurcated probes and lighted accessories." -ASD Inc.

The Reddy lab utilizes the ASD Spec 4 Hi-Res Analytical Instrument  to investigate the spectral properties of materials from space, such as the compositions of Earth-based satellites as well as meteorites that arrive on Earth. These spectral calibrations are directly compared with the spectral observations of bodies that are physically in space in order to better characterize the objects that are nearest to Earth, and pose the greatest threat.


Avantes SensLine AvaSpec-ULS2048LTEC

"Long integration times in general are equivalent to higher dark noise. Avantes Thermo-Electric Cooled (TEC) spectro-meters systems overcome this problem by cooling the detector. These recently re-designed instruments are equipped with triple stage cooling, keeping the detector at an optimal 5 degrees Celsius (maximum -35°C difference from ambient temperature). The detector cooling provides a significantly lower and more stable dark baseline and PRNU level. Dark noise is reduced by a factor of 2-3. This allows the ULS2048LTEC to be used in very low light conditions." - Avantes 


  • Wavelength Range: 200-1100 nm
  • Resolution: 0.06-20 nm
  • Sensitivity: 470,000 counts/µW  per ms integration time
  • Detector: CCD linear array, 2048 pixels


Nicolet™ iS™ 50R Benchtop FTIR 


"The Nicolet IS50R is Thermo Scientific's premier research FT-IR Spectrometer. The Nicolet IS50R incorporates the latest electronic and digital technology for advanced continuous scan, step-scan, and dual channel applications. The Vectra series interferometer offers the best mirror position accuracy in the industry. Precise positioning of the moving mirror is critical to the ultimate signal-to-noise ratio of the experiments. Unlike traditional air bearing and mechanical interferometers, the Vectra series interferometer in nearly immune to normal laboratory vibrations and acoustic noises making an ideal choice for the most sensitive and highly demanding step scan experiments. All configurations of the Nicolet IS50R support amplitude modulation and time-resolved step-scan spectroscopy. The optimal Vectra-Piezo interferometer adds advanced phase and multiple modulation capabilities" -Thermo Fisher Scientific

  • Step Scan Control System
  • 0.09 cm-1 resolution
  • ATR Built-in, wide range diamond ATR and Gr ATR

Nicolet Continuum IR Microscope

  • Infinity Corrected Optics for Highest Quality IR and Visible Light Rentention
  • On-Axis Optics with Coincident IR and Visible Light Paths
  • Targeting Sample Illumination
  • TruView, Continuous View/Sample Operation
  • Motorized, ReFlex Pre and Post Sample Masking Aperture with X, Y and theta Control
  • Automated Reflectance/Transmission Sampling Modes
  • 50 Watt Brightfield Koehler Transmission Illumination with intensity and contrast control
  • 50 Watt Brightfield Koehler Reflectance Illumination with intensity and contrast control
  • Integrated Contact Alert Electronics 
  • 50 μm MCT-A* Detector (11,400-700 cm-1)
  • InGaAs Detector (11,700-3800 cm-1)