THEMIS/GBO 1 Banff, March 29, 2006 Agenda – GBO Review

THEMIS/GBO 2 Banff, March 29, 2006 Ground Based Observatories (GBO) Requirements and overview H. U. Frey University of California - Berkeley

THEMIS/GBO 3 Banff, March 29, 2006 GBO Team Institutions University of California – Berkeley (UCB) S. B. Mende – GBO science lead Provides ASI development, system engineering, GBO system fabrication and construction, data archive and dissemination, deployment of 4 stations in Alaska University of California – Los Angeles (UCLA) C. T. Russell – magnetometer science lead Develop and provide ground magnetometer and GPS for GBO / EPO University of Calgary E. Donovan – Canadian science lead Providing GBO system deployment (16 stations) in Canada, field management, data collection, development participation University of Alberta I. Mann – magnetometer scientist Providing access to Canadian magnetometer network

THEMIS/GBO 4 Banff, March 29, 2006 GBO Site Locations IMAGE FUV substorm onset identification Of 1173 events indicated within GBO longitude sector, 2% are outside the FoV of all- sky cameras

THEMIS/GBO 5 Banff, March 29, 2006 Examples of collected data

THEMIS/GBO 6 Banff, March 29, 2006 GBO Science Objective GBO shall monitor the auroral light and ionospheric currents across North America in order to localize the time, location, and evolution of the auroral manifestation of the substorm. Themis mission requirement relating to GBO: Determine substorm onset time and onset meridian magnetic local time (MLT) using All Sky Imagers (one ASI per MLT hr) and Ground Magnetometers (two GMAG per MLT hr) with t_res<30s and dMLT<1° respectively, in an 8hr geographic local time sector in North America.

THEMIS/GBO 7 Banff, March 29, 2006 GBO Derived Requirements

THEMIS/GBO 8 Banff, March 29, 2006 ASI Requirements REQUIREMENTSYSTEM DESIGN GB.ASI-1: FOV. The field of view of the ASI shall be greater than 170°, full angle. Compliance. Yes GB.ASI-2: Exposure Time. Shall have an exposure duration that is programmable with a maximum exposure duration of no less than 1 second. Compliance. Yes GB.ASI-3: Spectral Response. Within passband of 400 to 700nm, shall provide detectable response when stimulated with a source radiance less than 10kRayleigh, at maximum specified exposure duration. Compliance. Expect minimum sensitivity < 1kR (5:1 SNR) GB.ASI-4: Spatial Resolution. Shall provide aurora onset localization with accuracy better than 100km (dMLT< 1°) Compliance. Raw ASI image will have > 250 pixel resolution per image diameter. Thumbnails will have 0.5° binning. GB.ASI-5: Viewport. Shall have heated dome viewportCompliance. Yes GB.ASI-6: Cadence Shall have a programmable repetition interval, minimum interval of no less than 10 seconds Compliance. Running at 3s since February.

THEMIS/GBO 9 Banff, March 29, 2006 Magnetometer Requirements REQUIREMENTSYSTEM DESIGN GB.GMAG-1: Timing. The time accuracy shall be better than 0.5 sec. Compliance. Yes, 1msec with GPS. GB.GMAG-2: Sampling. Shall have a sampling rate of better than 1 second. Compliance. Yes, 0.5 sec. GB.GMAG-3: Sensitivity. Shall be better than 1 nT.Compliance. Yes, 0.1 nT.

THEMIS/GBO 10 Banff, March 29, 2006 Observatory Requirements REQUIREMENTSYSTEM DESIGN GB.OBS-1: Shall provide unattended operation of instruments, data acquisition and storage for up to 4 months per observation season Compliance. Will operate for 12 months/yr GB.OBS-2: Shall provide interface to enable periodic upload of new observation parameters and operating software. Compliance. Internet connectivity provides secure login and file transfer GB.OBS-3: Shall provide digital interfaces and digital data storage for the ASI and GMAG. Compliance. Linux OS supports serial, USB, 10BaseT, etc. GB.OBS-4: Shall provide a GPS receiver for geographic position calibration and time stamp Compliance. GPS included in GMAG subsystem, provides better than 50ms accuracy. Synchronous image acquisition. GB.OBS-5: Shall provide a means for daily uplink of Level 1 (compressed) data, at least 3MB/day Compliance. Satellite Internet connection has demonstrated 10kbps sustained uplink. Provides > 100MB/day GB.OBS-6: Observatory shall store high resolution, Level 0 data locally on hard drives, at least 24GB/month Compliance. USB (or Firewire) drives, 80GB to 120GB, will be periodically swapped by site custodian. Selective transfer of high res. data via Internet is also planned GB.OBS-7: Observatory shall be compatible with locally provided power Compliance. 120 VAC, 60Hz, 10A service, backed up by UPS. UPS sized for 1 hour battery operation (excl heaters) GB.OBS-8: Shall provide controlled power-up and power- down of instruments and system computer automatically Compliance. System power and shutdown/re-boot sequencing controlled by independent control processor GB.OBS-9: Operate in external ambient temperatures range from -50° to +40°C Compliance. Enclosures, insulation, heaters and control designed to keep internal temperatures at 20º ± 10º C GB.OBS-10: Shall survive transport to site and provide stable mounting at the site Compliance. Yes

THEMIS/GBO 11 Banff, March 29, 2006 Ground Site Requirements REQUIREMENTSYSTEM DESIGN GB.GS-1: GBO sites shall provide largely unobstructed viewing over 160° hemisphere. Compliance. Site selection criteria GB.GS-2: GBO sites shall be reasonably clear of local magnetic interference. Compliance. Site selection criteria GB.GS-3: Each GBO site shall provide power, 120 VAC, single phase, 60Hz, at least 10A service Compliance. Site selection criteria GB.GS-4: Each GBO site shall have a local custodian available for periodic maintenance and Level 0 data retrieval Compliance. Site selection criteria