Image Frame Cropping 270 x 270 250 x

Image Frame Cropping 270 x 270 250 x 250 230 x 230 THEMIS/GBO CDR Peer Review Univ. of Calgary, Apr. 26 -27, 2004

Image Readout Time THEMIS/GBO CDR Peer Review Univ. of Calgary, Apr. 26 -27, 2004

Imager Data Flow: On-Site imagerd recent. pgm_reshape thumbnail. pgm udp_sendfile system disk backup udp_receiverd archive disk THEMIS/GBO CDR Peer Review archive disk Univ. of Calgary, Apr. 26 -27, 2004

Image meta-data Requires star frames after installation Instrument #"Site name" University of Calgary #"Site uniqueid" calgu #"Site description" Physics building roof #"Geodetic latitude" 51. 7 N #"Geodetic longitude" 245. 8 E #"Geodetic altitude" 1140 m #"Site information revised" 2004 -03 -17 #"Imager orientation" yaw=0. 0 pitch=0. 0 roll=0. 0 #"Imager uniqueid" themis 01 #"Imager type" starlight Xpress MX 716 #"Expose pgm" /usr/local/bin/starlight_expose_pgm #"Ccd width" 752 pixels #"Ccd height" 290 pixels #"Pixel depth" 16 bits #"Pixel aspect ratio" 0. 5238 Can be determined before installation, #"Optical type" THEMIS all-sky #"Optical projection" a 1=1. 5 a 3=0. 0 b 2=0. 0 b 4=0. 0 should be similar for all THEMIS #"Optical center" x 0=128 y 0=128 imagers #"Imager information revised" 2004 -03 -17 Image Site Essential information attached to each image on site: #"Image size" 270 #"CCD device" /dev/ccd. A #"Exposure options" XOFFSET=130 YOFFSET=10 WIDTH=540 HEIGHT=270 XBIN=2 YBIN=1 MSEC=1000 #"Exposure start time" 2004 -03 -25 12: 24: 00. 182015 UTC #"Exposure duration" 1119. 64 ms THEMIS/GBO CDR Peer Review Univ. of Calgary, Apr. 26 -27, 2004

Imager Geometry and Orientation Ø Hundreds of stars are visible in a 1 second exposure when skies are clear. Ø Minimization techniques allow estimation of parameters related to camera optics and imager orientation. Ø Resulting angular uncertainties are less than ½° over most of the field of view. THEMIS/GBO CDR Peer Review Univ. of Calgary, Apr. 26 -27, 2004

Composite Star Map THEMIS/GBO CDR Peer Review Univ. of Calgary, Apr. 26 -27, 2004

Star Visibility Time-Series THEMIS/GBO CDR Peer Review Univ. of Calgary, Apr. 26 -27, 2004

Image Thumbnails full resolution 256× 256 pixel image reduced to a 20× 20 pixel “thumbnail” pgm_reshape_filename image_filename > thumb_filename reshape_file is a standard PGM image with pixel values corresponding to indices in the thumbnail (look-up table) THEMIS/GBO CDR Peer Review Univ. of Calgary, Apr. 26 -27, 2004

Data Products Merged maps and movies for quick-look science and public outreach. Lower resolution, lossy formats, 1 minute cadence. CDF files with luminosity (8 bit) from 20× 20 grid at each of 20 sites, plus corresponding azimuth, zenith angle, geographic latitude/longitude (110 km and 150 km), PACE latitude/longitude (110 km and 150 km). File size would be roughly 10 megabytes for a 24 hour sequence at 1 minute cadence. THEMIS/GBO CDR Peer Review Univ. of Calgary, Apr. 26 -27, 2004

Project Data Flow thumbnail RAID thumbnail syslog thumbnail realtime. phys. ucalgary. ca syslog thumbnail syslog themis. phys. ucalgary. ca public data RAID Off-line Archive THEMIS team shipping Integration Disks from sites THEMIS/GBO CDR Peer Review Univ. of Calgary, Apr. 26 -27, 2004

Operational Monitoring A web interface can expose information from several different telemetry streams at various levels of complexity. The emphasis is on rapid detection and identification of problems, with a minimum of science-level data included only for instrument function validation. THEMIS/GBO CDR Peer Review 11 Univ. of Calgary, Apr. 26 -27, 2004