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.

note

string

DEPRECATED. Do not use.

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.

block_id

integer

Identification ID of the block (used by some survey objects).

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.

scripted_id

integer

Links scheduled observations with their acquisition.

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.