OSIRIS Level 1 Data

We store several data products in HDF and Onyx formats. All of the data is referenced by the orbit number during which it was collected. The file lookup is handled by the readlevel1.Orbit class in the osirisl1services.readlevel1 module. Files are opened using methods within the osirisl1services.pyhdfadapter module.

These data files are opened by the functions below:

• readlevel1.open_level1_attitude()

• readlevel1.open_level1_housekeeping()

• readlevel1.open_level1_spectrograph()

• readlevel1.open_level1_ir()

• readlevel1.open_level1_ecmwf()

OSIRIS Attitude Data

These data files contain information about the position and velocity of the Odin satellite over time. They also contain information on the beginning and end of each scan during the orbit, as well as each scan’s altitude range. Optionally, users can load data on the pointing of the OSIRIS instrument and line of sight data computed by SSC.

OSIRIS Housekeeping Data

These files contain information about the voltage states of on-board electronics, as well data on the temperature of various instrument components. The dataset further stores data on the minimums, maximums, and averages of these metrics. Finally, the housekeeping data files store information on the states of various components, as well as command history.

OSIRIS Spectrograph Data

Spectrograph files contain all data pertaining to the optical spectrograph portion of OSIRIS. Most notably, these files store the level 1 radiance data and error used for retrieval of trace gas and aerosol profiles in the atmospheric limb. Auxiliary to this main data product, spectrograph also contain information regarding spectrograph operation. This data includes the temperature of the optics, the id code of the imaging mode used for radiance data collection, etc. Users can optionally load audit data regarding the calibration of the collected data.

OSIRIS IR Data

Similar to spectrograph data files, but with infrared data. Opening these files requires specifying the infrared channel the user is interested in pulling data from. Like the spectrograph datasets, the IR datasets contain both the raw data, and information on the operating state of the instrument.

OSIRIS ECMWF Data

ECMWF data files contain data on the atmospheric state (density and temperature) of the atmosphere being scanned. This data is taken from the databases of the European Centre for Medium-Range Weather Forecast. We use this data to assist in retrieving accurate profiles of atmospheric constituents.