Scheduler-oriented night summary of lsstcam on 2026-04-13¶

This report is a summary of a night of observing designed to understand scheduler behavior during the night, identify scheduler problems, and otherwise monitor scheduler performance.

All data used for this page comes from "quick look" processing, not the full science processing.

Sunset: 22:21:26Z, evening 12°: 23:17:26Z, morning 12°: 10:09:33Z, Sunrise: 11:05:39Z

	MJD(UTC)	LST	UTC	Chile/Continental
event
sunset	61143.931553	106.726423	2026-04-13 22:21:26.171606+00:00	2026-04-13 18:21:26.171606-04:00
sun_n12_setting	61143.970451	120.768150	2026-04-13 23:17:26.984638+00:00	2026-04-13 19:17:26.984638-04:00
sun_n18_setting	61143.989747	127.733778	2026-04-13 23:45:14.170928+00:00	2026-04-13 19:45:14.170928-04:00
sun_n18_rising	61144.403984	277.267288	2026-04-14 09:41:44.226650+00:00	2026-04-14 05:41:44.226650-04:00
sun_n12_rising	61144.423305	284.241822	2026-04-14 10:09:33.544613+00:00	2026-04-14 06:09:33.544613-04:00
sunrise	61144.462268	298.306988	2026-04-14 11:05:39.967753+00:00	2026-04-14 07:05:39.967753-04:00
moonrise	61144.332080	251.310772	2026-04-14 07:58:11.671693+00:00	2026-04-14 03:58:11.671693-04:00
moonset	61144.857391	80.940590	2026-04-14 20:34:38.567375+00:00	2026-04-14 16:34:38.567375-04:00
night_middle	61144.196911	202.516706	2026-04-14 04:43:33.069680+00:00	2026-04-14 00:43:33.069680-04:00

Sun α=22.0°, δ=9.0° Moon α=342.0°, δ=-7.0°

	RA	dec	alt	az	phase
sun	22.111720	9.266893	-69.098716	179.127549	NaN
moon	342.494042	-6.822635	-36.989153	127.453650	23.683022

Number of exposures: 443, Mean gap time: 36.17 seconds, Median gap time: 8.84 seconds

Open shutter of first exposure	9.27 minutes after 12 degree evening twilight
Close shutter of last exposure	154.48 minutes before 12 degree morning twilight
Total wall clock time	8.14 hours
Number of exposures	443
Total open shutter time	3.70 hours
Mean gap time	36.17 seconds
Median gap time	8.84 seconds

Number of survey visits in night: 433, DDFs Observed: COSMOS, ToOs Observed: -

Time between 12 degree evening and morning twilights	10.87 hours
Number of survey visits in night	433
Number of pairs started	178
Number of pairs finished	178
DDFs Observed	COSMOS
ToOs Observed	-

Visit map¶

Map key and instructions

The above plots show the visits collected during the night in two different representations, modeled after physical observing tools.

The map on the left shows the sphere in orthographic projection, with the center point of the projection controlled by the sliders beneath the plot. A static orthogrophic projection is not an equal-area projection, but playing with the sliders is a helpful way to inform a human's spatial reasoning in three dimensions. Use of this map resembles use of an armillary sphere.
The map on the right shows the sky in Lambert Azimuthal Equal Area Projection, centered at the south celestial pole, with R.A. increasing counterclockwise (because Rubin Observatory is in the southern hemisphere). The projection used is equal area, but highly distorted near the north celestial pole (outside the LSST footprint). This is a particularly helpful representation for planning observing, because changes in time in relevant features are simple rotations, without alterations in distortion, and there are no discontinuities anywhere in the footprint at any time of year. Use of this map resembles use of a planisphere.

Both plots show the footprints of camera pointing taken up to the time set by the "Date and Time" slider, with the most recent three pointings outlined in cyan. The fill colors are:

u band
g band
r band
i band
z band
y band

Both plots have the following additional annotations:

The gray lines outline regions in the LSST survey.
The orange disk shows the coordinates of the moon.
The yellow disk shows the coordinates of the sun.
The green line (oval) shows the ecliptic.
The sun moves along the ecliptic in the direction of increasing R.A. (counter-clockwise in the planisphere figure) such that it makes a full revolution in one year.
The moon moves roughly (within 5.14°) along the ecliptic in the direction of increasing R.A. (counter-clockwise in the planisphere figure), completing a full revolution in one sidereal month (a bit over 27 days), about 14° per day.
The blue line (oval) shows the plane of the Milky Way.
The black line shows the horizon at the time set by the MJD slider.
The red line shows a zenith distince of 70& deg; (airmass=2.9) at the time set by the MJD slider.

Value timelines¶

Details on how the above values are computed.

Select a value to plot in the subplot on the right using the dropdown at the top of that subplot.

s_ra, s_dec, altitude, azimuth, and eff_time_median are values read directly from consdb.
seeingFwhmGeom is computed from consdb columns as seeingFwhmGeom = psf_sigma_median * (2 * np.sqrt(2*np.log(2))) * 0.2, where (2 * np.sqrt(2*np.log(2))) is the FWHM of a Gaussian with sigma=1 and 0.2 asec/pixel is a rough pixel scale.
skyBrightness is computed from consdb columns using skyBrightness = zero_point_median - k*airmass - 2.5*log10(sky_bg_median/(0.2**2)), where k is a typical extinction for the band (not measured on this night in particular), and 0.2 asec/pixel is a rough pixel scale.
nest_healpix is the healpixel ID in nested form, with nside=128. This is useful because similar values usually indicate nearby locations on the sky, and jumps in value usually indicate longer slews. (This is not always true, but it is a better indicator than working from R.A. or Decl. alone. Uncollapse the map below for a key.)

Map of nest_heapix values over the LSST footprint

No description has been provided for this image

Night visit metric maps¶

In all of the maps that follow, annotations are similar to those of the "Visit Map" above:

The orange disk shows the coordinates of the moon.
The brown disk shows the coordinates of the sun.
The green line (oval) shows the ecliptic.
The blue line (oval) shows the plane of the Milky Way.

Maps of numbers of visits and depth¶

Visits on 2026-04-13

Visits before 2026-04-13

Maps of coadd photometric depth expressed as inverse variance of noise (scaled to be an effective exposure time)

The following map shows accumulated inverse variance of visits completed on this night, a uniformly increasing measure of progress toward a target limiting coadd limiting magnitude. The inverse variance of the noise is increases linearly with the number of exposures for exposures of uniform depth, and total exposure time when noise is dominated by sky brightness, and so is scaled to a time under reference conditions and called the "effective exposure time:" the numeric scaling is the number of seconds of exposure time under a reference set of conditions that it would require to attain the same limiting magnitude. See DMTN-296: Calculations of Image and Catalog Depth for more details.

u band on 2026-04-13

u band before 2026-04-13

No visits in g band on 2026-04-13

g band before 2026-04-13

$No description has been provided for this image$

r band on 2026-04-13

r band before 2026-04-13

i band on 2026-04-13

i band before 2026-04-13

z band on 2026-04-13

z band before 2026-04-13

No visits in y band on 2026-04-13

y band before 2026-04-13

DDF Cadence¶

The y-axis (height of the vertical bars) represents the accumulated effective exposure time, t_eff (as defined above) accumulated over all exposures on the field for the night, colored by filter.

Observation Reason Hourglass¶

The hourglass plot below shows the observation reason for each visit over the past month. Each horizontal band represents a timeline for a day. The gray background shows twilight, while the black background is fully night. The moon rises or sets where the dotted line crosses each night's horizontal line, and transits where the thick solid line crosses it.

Visit details¶

You can also explore visits by

Downloading them as json here
Going to the Rubin schedule viewer page for this night