README web version of /home/usg/OPS/MTS/readme_xml/readme_79501600
Principal Investigator Email Address
Estimated Total Execution Time (hours, including overheads)
General Description
General Description
The goal is to recover comet 85P/Boethin, the target of the DIXI
mission. This is a mission critical observation; we must find the
comet. The comet may be as faint as mag 25, and the error ellipse
(LOV) is about 45 arcmin in length (and 0.5 arcsec in width), and by
searching out to 1.75 times the length of the LOV (78 arcmin) we cover
the 99th percentile for all possible orbit errors for the comet.
1. Each OB contains 5 shorter exposures dithered to remove the chip gap.
2. Each field position will be visited 3 times to be able to identify
moving objects and determine rates of motion.
3. The comet should move 20-30" between the first and last visit to
ensure it won't be hidden on a bright star in all visits. Ideally
the time between the first and last visit should be more than 1.5
hour, but all three visits from any one field should be done on
one night. The minimum ideal sequence of observations would be
Field01 Visit 1
Field02 Visit 1
Field01 Visit 2
Field02 Visit 2
Field01 Visit 3
Field02 Visit 3
A sequence of
Field01 Visit 1
Field01 Visit 2
Field01 Visit 3
Does not allow for 20" of motion from visit 1 to 3 on all dates. It
is acceptable only if no other choice, but compromises program.
4. Observations must be guided at nonsidereal rates.
5. We will use the standard Calibration plan, including photometric
standards.
6. We require clear conditions and Airmass < 2.0 to ensure ~7+ hrs of
visibility and only moderate degradations of image quality and extinction.
Waiver Requests
Critical Observing Condition Constraints
We need to have clear conditions, without moon impacting the observations
(because the object is very faint). Seeing should
be better than 1.2 arcsec. Certain of our fields cannot be obtained on all nights
because a Globular cluster is passing through
the fields. Below is a table which outlines when certain fields cannot be observed
because of this (X= No Observing)
Jul 10 11 12 13 14 15 16 17 18 19 (UT Date)
Field 1 OK OK OK X X X OK OK OK OK
Field 2 OK OK OK OK X X X OK OK OK
Field 3 OK OK OK OK X X X X X OK
Field 4 OK OK OK OK OK X X X X X
Field 10 OK OK OK OK OK OK OK OK OK OK
Field 11 OK OK OK OK OK X OK OK OK OK
Field 12 OK OK OK OK OK OK X OK OK OK
Field 13 OK OK OK OK OK OK OK OK OK OK
Time-Critical Aspects
Time-Critical Aspects
The LOV can be divided into 13 FORS2 fields. The 3 fields in the
W (Fields 1, 2 and 3) and E (Fields 11, 12 and 13) have the highest
priority because they have never been imaged before. We will only
be imaging 2 of the central fields (4 and 10) because of the time
allocation for this program. Note that the order in which the OBs
is executed is important.
- After UT Jul 12 a globular cluster begins to cross over the W portion
of the LOV, and these observations need to be accomplished early in
the Queue window.
- After July 17, the moon begins to affect our program.
*Strategy:
- Execute all of the Field 1 visits before UT Jul 13 (cluster interference)
Because queue mode is only during second half of night on these dates,
we have to accept the less desirable sequence of doing only one
field per night on the half nights. Each OB has 5 exposures.
- Execute W fields in order 1, 2, 3
- If West fields not executed before UT July 13, they are possible without
contamination from cluster on UT July 17, 18 and 19.
For observing periods where whole night is queue mode:
- Execute preferentially a "super OB" consisting of (3:49)
MOV-Boethin_W_Visit1_Field01
MOV-Boethin_W_Visit1_Field02
MOV-Boethin_W_Visit1_Field03
MOV-Boethin_W_Visit2_Field01
MOV-Boethin_W_Visit2_Field02
MOV-Boethin_W_Visit2_Field03
MOV-Boethin_W_Visit3_Field01
MOV-Boethin_W_Visit3_Field02
MOV-Boethin_W_Visit3_Field03
- If at all possible, complete the E and W chunks as close in time as
possible (e.g. same nights, adjoinging nights).
- Central portion, fields 4 and 10 have lower priority, than E-W
chunks but field 4 cannot be done after July 14 because of the
cluster
Special Execution Requirements
-For each OB: Update the coordinates from the ephemerides for that
Field (they are all different) AND update the non-sidereal guiding rates.
and update finder
- it was only possible to attach 4 finders per OB, but there are 10 finders
for each. These have been sent to Olivier Hainaut and will be available
at the telescpe
- Please cc ohainaut@eso.org and s.c.lowry@qub.ac.uk on all questions and
discussion pertaining to this program.
Special Calibration Information
ToO Information
ToO Activators List
Is this a Pre-imaging run ?
Pre-imaging Requirements
Source(s) of Pre-imaging
Pre-imaging sources not listed above
Do all your OBs comply with the instrument-specific requirements listed
on the instrument-specific Phase 2 web page ?
If this is a pre-imaging run, did you select PRE-IMAGING for the Observing
Category for each Observing Template ?
Do all your finding charts comply with both the general and instrument-specific
Phase 2 Web Pages ?
If you submitted OBs for standard stars, did you specify the magnitude
and spectral type of all standard stars in the OBs ?
Have you included OBs for any calibrations that you need but which are
not part of the Calibration Plan ?
If you are observing Moving Targets, have you attached suitable ephemeris
files to your OBs?
If you have preferences which OBs should be executed first, did you make
use of the User Priority field in the OBs ?
If this is a run that requires coordinated observations with other facilities,
did you give proper instructions in the Time-Critical Aspects Section ?
If you have prepared your finding charts with tools other than FIMS,
do they comply with the specifications on the FORS1 Phase 2 web page ?
Last creation of page: Tue Oct 6 15:40:20 2009
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