PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM LABEL_REVISION_NOTE = "20080521 - Initial Version; 20080528 - BSword, corrected keywords; 20090304 - EBowmanCisneros, Updated instrument description; 20090324 - BSword, minor syntax fixes 20100313 - EBowmanCisneros, final edits 20100610 - EBowmanCisneros, corrections" OBJECT = INSTRUMENT INSTRUMENT_HOST_ID = "LRO" INSTRUMENT_ID = "LROC" OBJECT = INSTRUMENT_INFORMATION INSTRUMENT_NAME = "LUNAR RECONNAISSANCE ORBITER CAMERA" INSTRUMENT_TYPE = "CAMERA" INSTRUMENT_DESC = " INSTRUMENT OVERVIEW =================== The LROC consists of two narrow-angle camera components (NACs), a wide-angle camera component (WAC), and a common Sequence and Compressor System (SCS). Each NAC has a 700 mm focal length Cassegrain (Ritchey-Chretien) telescope that images onto a 5000-pixel CCD line-array providing a cross-track field- of-view (FOV) of 2.85 degrees. The NAC readout noise is better than 76 e- and the data are sampled at 12 bits. By ground command, these 12 bit pixel values are companded to 8 bit pixels using one of several selectable piecewise linear mappings during readout from the CCD. The NAC internal buffer holds 256 MB of uncompressed data, enough for a full-resolution image 52,224 lines long (26-km from 50-km orbit). NAC specifications are summarized in Table 1. Table 1 - NAC Specifications [ROBINSONETAL2010] --------------------------------------------------------------------------- NAC-L NAC-R --------------------------------------------------------------------------- FOV = 2.8502 deg 2.8412 deg IFOV = 10.0042 microrad 9.9764 microrad Image scale = 0.5 m/pixel 0.5 m/pixel (at 50 km altitude) Maximum Image size = 2.49 x 26 km 2.48 x 26 km (at 50 km altitude) f/# (Ritchey-Chretien) = 3.577 3.590 Effective Focal Length = 699.62 +/- 0.08 mm 701.57 +/- 0.09 mm Distortion coefficient = 0.0000181 +/- 0.0000005 0.0000183 +/- 0.0000005 Optical center location = sample 2548 +/- 8 sample 2568 +/- 8 Primary Mirror Diameter = 198 mm 198 mm MTF (Nyquist) = 0.23 0.23 Gain = 90.5 +/- 2.6 e-/DN 92.5 +/- 1.5 e-/DN Noise = 101 +/- 7 e- 97 +/- 1 e- Detector Fullwell = 334,000 +/- 31,000 e- 352,000 +/- 4100 e- SNR (400-750 nm) = > 42 > 42 Detector Digitization = 12 bit, encoded to 8 bits Compression = 1.7:1 Structure + baffle = Graphite-cyanate composite Detector = Kodak KLI-5001G Pixel format = 1 x 5,064* Analog/Digital Converter = Honeywell ADC9225 FPGA = Actel RT54SX32-S Voltage = 28 +/- 7V DC Peak Power = 9.3 W Average Power = 6.4 W Mass (both NACs) = 16.4 kg Volume = 118 cm x 27 cm (incl. radiator) (lengthxdiameter) ---------------------------------------------------------------------------- * Of the 5064 pixels, 39 masked pixels on the right and 21 masked pixels on the left are used for dark reference, with 4 transition (non-imaging) pixels immediately preceding the 21 masked pixels. The WAC electronics are a copy of those flown on cameras on Mars Climate Orbiter, Mars Polar Lander, Mars Odyssey, and Mars Reconnaissance Orbiter. The WAC has two lenses imaging onto the same 1024 x 1024 pixel, electronically shuttered CCD area-array, one imaging in the visible/near infrared (VIS), and the other in the Ultraviolet (UV). In monochrome mode, 1024 x 14 pixels are ed out from one of the five visible bands. In color mode, only the center 704 x 14 visible pixels and 512 x 16 UV pixels, which are binned to 128 x 4, are read out for each band. The VIS optics have a crosstrack FOV of 91.7 degrees (monochrome) and 61.4 degrees (color), and the UV optics a 58.96 degree FOV. From the nominal 50-km orbit, the WAC will provide a nadir ground sample distance of 74.9 m/pixel in the visible, and a swath width of 104.6 km (visible monochrome), 59.6 km (visible color) and 56.8 km (UV color). The seven-band color capability of the WAC is provided by a color filter array (see Figure 1) mounted directly over the detector, providing different sections of the CCD with different filters. Consequently the instrument has no moving parts; it acquires data in the seven channels in a 'pushframe' mode, with scanning of the WAC FOV provided by motion of the spacecraft and target. Continuous color coverage of the lunar surface is possible by repeated imaging such that each of the narrow framelets of each color band overlap. The WAC has a readout noise less than 70 e- and, as with the NAC, pixel values are digitized to 11 bits and are then companded to 8 bit values through a square-root-like lookup table. WAC specifications are summarized in Table 2. The two UV bands (320 and 360 nm) undergo 4x4 pixel on-chip analog summing before digitization to achieve better signal-to-noise ratio. Thus, UV pixels are recorded at reduced 383.5 m/pixel sampling but have improved signal properties. Only the center 704 pixels for the visible are digitized when all seven bands are being acquired. WAC band passes are arranged first UV then VIS (320, 360, 415, 565, 605, 645, 690), but the order is reversed after LRO performs a 180 degree yaw maneuver to align the solar panels with the sun. Figure 1 - WAC Color Filter Array --------------------------------------------------------------------------- __________________________________________________ | | | VISIBLE TRANSMITTING AREA | | | | UV1 (360 nm) | | | |--------------------- (+)<-- UV Optical Axis --| | | | UV2 (300nm) | | | |xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx| Zoom-in of Visible |xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx| Array |xxxxxxx UV & VISIBLE (200 - 1100 nm) xxxxxxxxxx| |xxxxxxxxxxxxxxx OPAQUE AREA xxxxxxxxxxxxxxxxxxx| /-|----------------| |xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx| | | VIS1 (415nm) | |-----------------------------------------------|/ |----------------| |-----------------------------------------------| | VIS2 (560nm) | |-----------------------------------------------| |----------------| |- VIS Optical Axis -->(+) ---------------------| | VIS3 (600nm) | |-----------------------------------------------| |----------------| |-----------------------------------------------| | VIS4 (640nm) | |xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx|\ |----------------| |xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx| | | VIS5 (690nm) | | xxxxxxx UV & VISIBLE (200 - 1100 nm) xxxxxxx | \-|----------------| | xxxxxxxxxxxxxxx OPAQUE AREA xxxxxxxxxxxxxxxx | | xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx | | xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx | |-----------------------------------------------| Table 2 - WAC Specifications [ROBINSONETAL2010] ------------------------------------------------------------------------ Visible UV ------------------------------------------------------------------------ FOV (monochrome / color) = 91.9 deg / 61.4 deg 59.0 deg IFOV = 1.498 mrad 7.67 mrad (4x4 binned) Image scale = 74.9 m/pixel 383.5 m/pixel (binned) (nadir, 50 km altitude) Image frame width monochrome = 104.6 km - Image frame width 7-band color = 59.6 km 56.8 km Image format monochrome = 1024 samples - x 14 lines Image format color = 704 samples 128 samples (for each band) x 14 lines x 4 lines (binned) f/# = 5.052 5.65 Effective Focal Length = 6.013 mm 4.693 mm Entrance Pupil Diameter = 1.19 mm 0.85 mm System MTF (Nyquist) = 0.37 Gain = 25.9 +/- 0.7 e-/DN Noise = 66 +/- 4 e- Detector fullwell = 46,100 +/- 3600 e- Band | #eff | FWHM | SNR = 320 nm 321 nm 32.3 nm 157 360 nm 360 nm 14.9 nm 147 415 nm 415 nm 36.1 nm 157 565 nm 566 nm 20.1 nm 157 605 nm 604 nm 20.4 nm 159 645 nm 643 nm 22.5 nm 157 690 nm 689 nm 38.6 nm 158 Detector Digitization = 11 bit, encoded to 8 bits Compression = 1.7:1 Electronics = 4 circuit boards Detector = Kodak KAI-1001 Pixel format = 1,024 x 1,024 Voltage = 28 +/- 7 V DC Peak Power = 2.7 W Orbit Avg Power = 2.6 W Mass = 0.9 kg Volume = 15.8 cm x 23.2 cm x 32.3 cm (width x length x height) (incl. radiator) ------------------------------------------------------------------------ * In BW mode, 1024 pixels are read out. In color mode only the center 704 VIS pixels are read out. The two NACs and the WAC interface with the Sequencing and Compressor System (SCS), the third element of the LROC. As the name implies, the SCS commands individual image acquisition by the NACs and WAC from a stored sequence delivered to the SCS by the LRO spacecraft, and losslessly compresses the NAC and WAC data as they are read out and passed to the spacecraft data system. The SCS provides a single command and data interface between the LROC and the LRO spacecraft data system through a spacewire interface. Each NAC has an estimated mass of 8.2 kg, the WAC is 0.9 kg, and the SCS is 0.6 kg, for a total LROC mass of 12 kg. Each NAC will use 10 W during image acquisition or readout, 6 W at all other times; the WAC will use 4 W (continuous), and the SCS will use 6 W (continuous), for a total LROC power dissipation of 30 W peak, 22 W average. Malin Space Science Systems, located in San Diego, California, designed and constructed the LROC instruments. Malin subcontracted the following: NAC optics and structure to LightWorksOptics (LWO) of Tustin, CA; Composite structure to Vanguard Composite Group (VCG) of San Diego, CA (VCG was the structure vendor (for Kaiser Electro-Optics) on CTX); WAC optics and structure to LightWorksOptics (LWO) of Tustin, CA; WAC Color Filter Assembly (CFA) to Barr Associates of Westford, MA. " END_OBJECT = INSTRUMENT_INFORMATION OBJECT = INSTRUMENT_REFERENCE_INFO REFERENCE_KEY_ID = "ROBINSONETAL2010" END_OBJECT = INSTRUMENT_REFERENCE_INFO END_OBJECT = INSTRUMENT END