Nightly Observing Plan for MJD 58455 (starting the evening of Dec 2, 2018)

DES has the full night.


  • Larissa Markwardt (Observer 1)
  • Nikolay Kuropatkin (Observer 2)
  • Martin Murphy (Run Manager)

CTIO Staff

  • Manuel Hernandez, Rodrigo Hernandez, Alberto Alvarez (night assistant)
  • Staff calendar


from kentools ephem

mjd 58455, date 20181202, Site CTIO, UT-offset 3 hr
Current local time 15:56 CLST     UT 18:56     SidTim 19:00
Event      Local-Time  Greenwich  Sidereal-Time
Sunset     20:39 CLST  23:39 UT   23:43  356 deg  
Eve. -10   21:19 CLST  00:19 UT   00:23    6 deg  Zeropoint; standards
Eve. -14   21:42 CLST  00:42 UT   00:46   12 deg  Begin obstac
Eve. -18   22:05 CLST  01:05 UT   01:09   17 deg  Last chance standards
Midpoint   01:32 CLST  04:32 UT   04:36   69 deg  
Moonrise   04:19 CLST  07:19 UT   07:23  111 deg  
Morn -18   04:59 CLST  07:59 UT   08:03  121 deg  Begin astronomical twilight
Morn -14   05:23 CLST  08:23 UT   08:27  127 deg  End obstac; begin standards
Morn -10   05:46 CLST  08:46 UT   08:49  132 deg  
Sunrise    06:26 CLST  09:26 UT   09:30  142 deg  
Moon position (deg): RA 202.3, Dec -3.1 Phase: 0.278

Weather Conditions

Observing Plan and Goals for the Night

  • DES full night
  • Evening standards
    UT Date = '2018/12/03 00:19'     Local time = 21:19
    SDSSJ0320-0000        ra 03:20:00  dec +00:00:00  secz 1.6
    SDSSJ0000-0000        ra 00:00:00  dec +00:00:00  secz 1.2
  • Morning standards
    UT Date = '2018/12/03 08:23'     Local time = 05:23
    E2-A                  ra 04:03:00  dec -44:41:45  secz 1.7
    SDSSJ1048-0000        ra 10:48:00  dec +00:00:00  secz 1.4
    SDSSJ0843-0000        ra 08:43:00  dec +00:00:00  secz 1.2

Useful links

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

Notes from 4PM Meeting

Rodrigo says calibrations are underway. Telescope and camera are good.

For tonight:

  • If seeing is bad (Bad means if the psf is > 1.6 arcsec for several exposures in a row with no sign of improvement. Choose which script to use based on the SN field that is transiting at the time the seeing is bad. Use to decide which one.)

If poor seeing is persistent complete Photosweep, then Narrowband (details below):


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