Nightly Observing Plan for MJD 58472 (starting the evening of Dec 19, 2018)

  • Richard Kron (Observer 1)
  • Qiqi Wang (Observer 2, Run Manager)

CTIO Staff


from kentools ephem

mjd 58472, date 20181219, Site CTIO, UT-offset 3 hr
Current local time 16:03 CLST     UT 19:03     SidTim 20:14
Event      Local-Time  Greenwich  Sidereal-Time
Sunset     20:51 CLST  23:51 UT   01:02   16 deg  
Eve. -10   21:32 CLST  00:32 UT   01:43   26 deg  Zeropoint; standards
Eve. -14   21:55 CLST  00:55 UT   02:06   32 deg  Begin obstac
Eve. -18   22:19 CLST  01:19 UT   02:30   38 deg  Last chance standards
Midpoint   01:40 CLST  04:40 UT   05:51   88 deg  
Moonset    04:51 CLST  07:51 UT   09:02  136 deg  
Morn -18   05:01 CLST  08:01 UT   09:12  138 deg  Begin astronomical twilight
Morn -14   05:26 CLST  08:26 UT   09:36  144 deg  End obstac; begin standards
Morn -10   05:49 CLST  08:49 UT   10:00  150 deg  
Sunrise    06:30 CLST  09:30 UT   10:41  160 deg  
Moon position (deg): RA 52.5, Dec 15.0 Phase: 0.794

Weather Conditions

  • At 21:00 local time, clear sky with no clouds, 14.8 degrees with light breeze (3.7 mph), humidity 22%
  • Tonight: Forecast, 12 degrees, light breeze from west, ~60% humidity
  • Detailed hourly forecast | Satellite maps

Observing Plan and Goals for h1. 12172018the Night

  • DES Half night
  • Evening standards
    UT Date = '2018/12/20 00:32'     Local time = 21:32
    MaxVis                ra 06:30:00  dec -58:45:00  secz 1.8
    SDSSJ2300-0000        ra 23:00:00  dec +00:00:00  secz 1.5
    SDSSJ0200-0000        ra 02:00:00  dec +00:00:00  secz 1.2
  • Midpoint standards
    UT Date = '2018/12/20 04:40'     Local time = 01:40
    SDSSJ0933-0005        ra 09:33:00  dec -00:05:00  secz 2.0
    SDSSJ0843-0000        ra 08:43:00  dec +00:00:00  secz 1.6
    MaxVis                ra 06:30:00  dec -58:45:00  secz 1.1

Useful links

Nightsum | CTIO Night Report | DECam Logbook
Tololo Environmental Web Page | Detailed hourly forecast | Satellite maps

Notes from 4PM Meeting

Calibrations started. All data from last night processed by DESDM,.
For tonight:

  • Do standards if clear.
  • If seeing < 1.3" in i-band and sky is clear, execute E2 narrow band script.
  • Run ObsTac
  • If sky is photometric, run star flat script in /usr/remote/user/DECamObserver/ExposureSCripts/Engineering/engineering_20181122 in g-band. Position needs to be manually put in before starting the script. Position is: RA: 06H 40M DEC: -34D 00M.
  • If sky is not photometric, obstac.

Clear for MACS field is clear or nearly so.
If you have "Bad Seeing" and photometric and not worse than 2.0", do
Photosweep. Instructions can be found here:

Do not bother with this program if clouds are visible on Rasicam or if
seeing is highly variable, for the varying aperture corrections make
it difficult to get to mmag accuracy.

One needs to run a script at CTIO to generate the jsons (see the
instructions wiki page). Having done that the Photosweep scripts can
be found in
with names like: photosweep20180914-2200Z.json

Select the one with timestamp closest to the next top of hour, now in
UT (we got the z added). Do not bother with this is there's < 30
minutes left in the night. A script probably takes an hour.

If "Bad Seeing" and not photometric, or if "Bad Seeing" and everything
else if done, then do Narrowband. Instructions and a description can be found here:

Narrowband scripts are in the same directory as Photosweep, and have names like SN-C3X-N964.json

They are on the SN fields, so select the field that is closest to transit. Transit time for SN fields can be found on this page:

These are expected to be about an hour long. If the clouds are only moderate, we could do these.

Priorities (highest to lowest)

Other Notes