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Hinode is a multi-instrument and wavelength mission designed to observe the Sun. It is a joint Japan/UK/US consortium (with ESA and Norwegian involvement). Launched in September 2006, its principal scientific goals are to study the Sun's variability and the causes of solar activity. Hinode operations are coordinated at ISAS (Tokyo, Japan). A daily Science Operations meeting is attended by the instrument teams and the spacecraft team. Nominally, science plan uploads cover periods of two or three days. When the forthcoming operations have been agreed, the necessary spacecraft operations parameters are created. These include scheduling for spacecraft pointing and ground stations. The Extreme UV Imaging Spectrometer (EIS) instrument, led by the UK (the PI institute is MSSL), is designed to observe the emission spectral lines of the solar atmosphere. Observations are composed of reusable, hierarchical components, including lines lists (wavelengths of spectral lines), rasters (exposure times, line list, etc.) and studies (defines one or more rasters). Studies are the basic unit of "timeline" scheduling. They are a useful construct for generating more complex sequences of observations, reducing the planning burden. Instrument observations must first be validated. An initial requirement was that operations be shared equally by the 3 main EIS teams (Japan, UK and US). Hence, a major design focus of the software was "Remote Operations", whereby any scientist in any location can run the software, schedule a science plan and send it to the spacecraft commanding team. It would then be validated and combined with the science plans of the other instruments. Then uploaded to the spacecraft. As for any space mission, telemetry size and rate are important constraints. For each planning cycle the instruments are issued a maximum data allocation. EISPT interactively calculates the telemetry requirements of each observation and plan. Autonomous operations was a challenging concept designed to observe the early onset of various dynamic events, including solar flares. The planning cycle precluded observers responding to such short-term events. Hence, the instrument can be run in a (low-telemetry) "hunter" mode at a suitable target. Upon detecting an event the current observation ceases and another automatically begins at the event location. This "response" observation involves a smaller field-of-view and higher cadence. It's impossible to predict if this mechanism will be activated, and if so how much telemetry is acquired. The EISPT has operated successfully since it was deployed in November 2006. Nominally it is used six days a week. It has been maintained and updated as required to take account of changing mission operations. A large update was made in 2013/14 to develop the facility to coordinate observations with other solar missions (SDO/AIA and IRIS). |
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Sun
Large Synoptic Survey Telescope
Cameras
Atmospheric modeling
Light scattering
Space operations
RGB color model
