Scheduler Output Schema

When running in simulation mode, the scheduler outputs a sqlite database containing the pointing history of the telescope, along with information about the conditions of each observation (visit). The table below describes the columns in the observations table.

All values are for the center of the field of view (e.g., airmass, altitude, etc)

Opsim Schema

Column	Units	Description
observationId	integer	Simple counter for the observation.
fieldRA	degrees	The Right Ascension of the boresight.
fieldDec	degrees	The Declination of the boresight.
observationStartMJD	MJD	The MJD of the start of the observation (UTC).
flush_by_mjd	MJD	The time by which to drop the queued observation from consideration.
visitExposureTime	seconds	Total on-sky exposure time.
filter	string	The name of the bandpass in use for the observation.
rotSkyPos	degrees	The orientation of the sky in the focal plane measured as the angle between ICRF North on the sky and the “up” direction in the focal plane. Corresponds to ‘skyAngle’.
rotSkyPos_desired	degrees	The rotSkyPos requested by the observation. Most likely to match rotSkyPos, but if the angle is unreachable, then backup values will be used.
numExposures	integer	The number of exposures in the visit.
airmass	unitless	The airmass of the visit, at the center of the field at the start of the visit.
seeingFwhm500	arcseconds	The seeing FWHM at zenith at 500 nm. The atmospheric contribution to the IQ.
seeingFwhmEff	arcseconds	The FWHM of the single-gaussian PSF that results in equivalent SNR for a point source, compared to the full realized PSF.
seeingFwhmGeom	arcseconds	The FWHM of a measured PSF, a measurement of the physical size of the (non-gaussian) PSF.
skyBrightness	mag/arcsecond^2	The skybrightness in the filter in use at the center of the exposure. Predicted from the skybrightness_pre module.
night	integer	The night of the survey for the observation.
slewTime	seconds	The time required to slew to this position on the sky. Includes filter change and readout, as well as slew and settle time.
visitTime	seconds	The total wall-clock time required for a visit. Longer than visitExposureTime if multiple exposures within a visit were acquired.
slewDistance	degrees	Distance required to slew to this pointing from the previous pointing.
fiveSigmaDepth	magnitudes	The magnitude of a five-sigma point source detection in the visit.
altitude	degrees	Altitude of the field at the start of the observation.
azimuth	degrees	Azimuth of the field at the start of the observation.
paraAngle	degrees	Parallactic angle of the observation, angle between True North and zenith.
pseudoParaAngle	degrees	Angle between ICRF North and zenith. See https://smtn-019.lsst.io/v/DM-44258/index.html
cloud	float	Fraction of sky which is cloudy. Simply used as an indicator to shut the telescope.
moonAlt	degrees	Altitude of the Moon.
sunAlt	degrees	Altitude of the Sun.
scheduler_note	string	Descriptive comment about how the observations were scheduled, for use by the FBS.
target_name	string	Descriptive name for the target. Only used for DDFs, ToOs, or other special targets. Should translate to target_name in the headers/ConsDB.
observationStartLST	degrees	Local Sidereal Time at the start of the observation.
rotTelPos	degrees	Angle between zenith and “up” in the camera. Camera rotator angle.
rotTelPos_backup	degrees	Angle specifying a backup for rotSkyPos_desired and rotTelPos.
moonAz	degrees	Azimuth of the Moon.
sunAz	degrees	Azimuth of the Sun.
sunRA	degrees	Right Ascension of the Sun.
sunDec	degrees	Declination of the Sun.
moonRA	degrees	Right Ascension of the Moon.
moonDec	degrees	Declination of the Moon.
moonDistance	degrees	Distance between the field pointing and the Moon.
solarElong	degrees	Solar Elongation of the field.
moonPhase	float	Lunar illumination, ranging from 0 (new moon) to 100 (full moon).
cummTelAz	degrees	Cumulative azimuth of the telescope mount, tracks cable wrap.
target_id	integer	Integer added by the CoreScheduler.
observation_reason	string	The reason for the observation. Identifier for DM. Translates to observation_reason in the headers/consdb.
science_program	string	The science program for the observation. This will typically track to a JSON BLOCK to execute for the scheduler and translates to science_program in the headers/consdb. An identifier for Scheduler and DM.