ObsHistory¶
This table keeps a record of each visit made by the observatory during a simulated survey. Multiple proposals can be associated with a single visit leading to duplicate entries in this table.
Column | Description |
---|---|
observationId | Numeric identifier for an observation entry. |
Session_sessionId | The simulation run session Id. |
night | The night in the survey for the observation. Starts from 1. |
observationStartTime | The UTC start time for the observation (units=seconds). This occurs after the slew but before the first exposure. |
observationStartMJD | The Modified Julian Date at observation start (units=seconds). |
observationStartLST | The Local Sidereal Time at observation start (units=degrees) |
TargetHistory_targetId | Numeric identifier that relates to an entry in the TargetHistory entry. |
Field_fieldId | Numeric identifier that relates to an entry in the Field table. |
groupId | Group Id for the observation. This is non-zero and repeated for field/filter combinations collected in sets of N (tuples or sequences). It is zero when N equal one. |
filter | The one character name for the band filter. |
ra | The Right Ascension of the observation (units=degrees). |
dec | The Declination of the observation (units=degrees). |
angle | The Position Angle of the observation (units=degrees). |
altitude | The altitude of the observation (units=degrees). |
azimuth | The azimuth of the observation (units=degrees) |
numExposures | The number of exposures taken for the observation. |
visitTime | The total time for the observation (units=seconds) including exposure, shutter and readout time. |
visitExposureTime | The sum of all the exposure times for the observation (units=seconds). No shutter and readout time included. |
airmass | The airmass of the observation field. |
skyBrightness | The calculated skybrightness for the observation field. |
cloud | The fraction of clouds present (0: none to 1: total). |
seeingFwhm500 | The full-width at half-maximum for seeing observations at 500 nm at zenith. |
seeingFwhmGeom | “Geometrical” full-width at half-maximum, actual half width at maximum brightness. This can be used to represent the FWHM of a double Gaussian representing the physical width of a PSF. |
seeingFwhmEff | “Effective” full-width at half-maximum, typically ~15% larger than seeingFwhmGeom. This can be used to calculate SNR for point sources, using seeingFwhmEff as the FWHM of a single Gaussian describing the PSF. |
fiveSigmaDepth | The magnitude of a point source that would be a 5-sigma detection (units=magnitudes) |
moonRA | The right-ascension (units=degrees) of the moon. |
moonDec | The declination (units=degrees) of the moon. |
moonAlt | The altitude (units=degrees) of the moon. |
moonAz | The azimuth (units=degrees) of the moon. |
moonDistance | The distance (units=degrees) between the moon and the observation field. |
moonPhase | The phase of the moon. |
sunRA | The right-ascension (units=degrees) of the sun. |
sunDec | The declination (units=degrees) of the sun. |
sunAlt | The altitude (units=degrees) of the sun. |
sunAz | The azimuth (units=degrees) of the sun. |
solarElong | The solar elongation (units=degrees) of the observation field (distance between it and sun). |