Nightly Observing Plan for MJD 57785 (starting evening of Jan 31, 2017)

Half night


  • Ting Li (Obs 1)
  • Sebastian Bocquet (Obs 2, RM)

CTIO Staff

  • Hernán Tirado - Obs. Support
  • Alberto Alvarez - Operator
  • Staff calendar


mjd 57785, date 20170131, Site CTIO, UT-offset 3 hr
Current local time 15:38 CLST     UT 18:38     SidTim 22:40
Sunset     20:49 CLST  23:49 UT   SidTim   58 deg  
Eve. -10   21:27 CLST  00:27 UT   SidTim   68 deg  Zeropoint; standards
Eve. -14   21:48 CLST  00:48 UT   SidTim   73 deg  Begin obstac
Eve. -18   22:10 CLST  01:10 UT   SidTim   78 deg  Last chance standards
Moonset    23:12 CLST  02:12 UT   SidTim   94 deg  
Midpoint   01:57 CLST  04:57 UT   SidTim  135 deg  
Morn -18   05:43 CLST  08:43 UT   SidTim  192 deg  Begin astronomical twilight
Morn Std   06:05 CLST  09:05 UT   SidTim  197 deg  End obstac; begin standards
Morn -10   06:26 CLST  09:26 UT   SidTim  202 deg  
Sunrise    07:04 CLST  10:04 UT   SidTim  212 deg  
Moon position (deg): RA 4.2, Dec -0.4 Phase: 0.259

Weather Conditions

Observing Plan and Goals for the Night

* Evening Standards: Yzirg.

UT Date = '2017/02/01 00:28'     Local time = 21:28
E4-A                  ra 09:23:44  dec -45:21:02  secz 1.9
SDSSJ0200-0000        ra 02:00:00  dec +00:00:00  secz 1.5
SDSSJ0320-0000        ra 03:20:00  dec +00:00:00  secz 1.2

* Defocus script
* Obstac: Mostly wide field
* If the seeing in i-band is better than 1.05", we will do cosmos-gri-part2.json around 1:15 CT (4:15 UT)
* Half Night standards (using calspec) use only 1 (highest airmass): grizY
UT Date = '2017/02/01 04:53'     Local time = 01:53
SDSSJ1227-0000        ra 12:27:00  dec +00:00:00  secz 1.9

When were the last SN fields observed?

(See for database query.)

hex_name     seqtype     last_complete
SN-X3    long_z    2017-01-26 00:55:51.528351+00:00
SN-E1    short    2017-01-27 00:53:18.591071+00:00
SN-X2    short    2017-01-27 01:14:13.977544+00:00
SN-X3    long_i    2017-01-27 01:33:32.157988+00:00
SN-E2    short    2017-01-28 00:53:06.852121+00:00
SN-X1    short    2017-01-28 01:14:15.665466+00:00
SN-X3    long_r    2017-01-28 01:33:29.425048+00:00
SN-X3    long_g    2017-01-29 01:04:14.492806+00:00
SN-S2    short    2017-01-29 01:17:20.589302+00:00
SN-S1    short    2017-01-29 01:36:41.706064+00:00
SN-C3    long_r    2017-01-29 01:57:12.786249+00:00
SN-C3    long_z    2017-01-29 02:20:30.702561+00:00
SN-C2    short    2017-01-31 00:48:51.012551+00:00
SN-C3    long_g    2017-01-31 01:12:08.842422+00:00
SN-C3    long_i    2017-01-31 01:33:23.812696+00:00
SN-C1    short    2017-01-31 02:22:33.431244+00:00

Notes from 4pm meeting

HTD, Sebastian, Ting, Hernan, Rick K, Gary, Michael, Eric N, Yanny, Bobby, Huan, Josh

Camera & Telescope
All OK. Flats are underway.

Last Night
All OK
No problems with Chrome
Seeing not great, so no Cosmos field.
Rasicam live image looked OK, but nightsum showed Rasicam with zero clouds and zero uncertainty.

SN: C1, C2, C3g, C3i

Desdm and DQ
Got all the data. All processed. All SN good. 1 WF bad.

Clear, clouds east. Forecast is clear.
Nothing on deadman 6. X3z is at 5 nights. Not sure if it will fit the airmass limit. Others on 4 nights.

--- * SN Turnoff Topics:
E1 & E2 are now disabled
7 night deadman is disabled
Modest seeing trigger is still enabled

It’s possible to force SN with json scripts
The SN discussion is now down to if/when we force SN observations with scripts.
My sense is that will depend on what happens with the seeing-triggered SN fields
in the nights ahead.

We want to make sure we get the C-fields late.

Eric N suggests a straw man plan so:
On Feb. 7, use a script to do X3-z at the start of the night.
Note that it will be a high airmass (~2.5) by the time it finishes
even if started first thing. As it is in z, this is good use of very
moony time. X3 is 68 degrees from the moon on this night.
(If do X3-z tomorrow night, on the evening of Feb 1, then it finishes with an
airmass of ~2.0. This means that, with the current airmass limit of 1.7,
it cannot be seeing triggered.)
On Feb. 8, the last night before the bright time break, do C3-z. Again, as
it is in z, this is good use of very moony time. C3 is 75 degrees from the moon
on this night.
On Feb. 15, the first night back, do the rest of the C3 filters.
(The start of this night is dark, so we can do the g and r filters well.)


  • Cosmos Field Deep Observations
    A second discussion is if/when we will do ~3 hours of deep field observations
    for photo-z calibration in the Cosmos fields at approximately RA/DEC 150.10/2.28
    The plan would be 10x330s exposures for each of r, g, and i bands, dithered so as to fill
    the CCD gaps while leaving the full COSMOS field in every exposure?
    This would be 1hr of clock time each, and give the observers instructions to do them whenever:
    r: dark and PSF<1”
    g: dark and PSF<1.1”
    i: dark or grey and PSF<1.0”
    in order of decreasing priority.
    This would have to be done in the late parts of our 1st halves.

Eric N suggest that if we are going to do this, that it is divided into six 30 minute scripts.
Huan will make the scripts.
Previous request for cosmos observations has priority.

Wildlife report: No snake, no panthers

WoD: 3 cheers for 3 years. (finished tile 6).