README web version of /home/usg/OPS/MTS/readme_xml/readme_84083100

Principal Investigator Email Address

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tmueller@mpe.mpg.de
```

Estimated Total Execution Time (hours, including overheads)

```
9 hours
```

General Description

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Readme-Information for program 384.C-0831(A)/SM/VISIR
"Thermophysical properties of (comet 107P)/(asteroid 4015)
 Wilson-Harrington"
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The goal of this program is to obtain *very high* photometric
accuracy for Wilson-Harrington (W-H). The observations require
therefore excellent observing conditions for N-band (good seeing
and low PWV). Within the approved time we would like to execute
9 blocks of repeated PAH1/SIV/NeII band measurements on W-H,
preferentially placed between calibration observation on nearby
stars close in time, in AM and in the same instrument and filter
settings. For the requested time period (1-Nov ... 20-Dec-2009)
we predicted fluxes of about 200/300/400 mJy for the PAH1/SIV/NeII
filters which should allow us to obtain S/N > 50 in 90/120/120 sec
integration time.

The final quality of the photometry will be limited by the
calibration stability over time and AM during the W-H
observations (duration of one block: about 65 min).

The success of this programme is connected to a nearly complete
coverage of the 6.1 hour thermal lightcurve of W-H when combining
all 9 observing blocks. This requires that the 9 blocks should
be executed as close in time as possible to avoid large changes
in the object's constellation (aspect and phase angles). But due
to the restricted visibility of W-H only a maximum of 2 blocks
can be executed in a single night. All 9 blocks should be
executed within about one week.

Notes:
* The target's apparent motion (as seen from VLT) is
  relatively high: between 182.9 and  271.4 arcsec/hour!
* Coordinates in the OBs are given for the mid-time of the
  requested period
* Ephemerides-files are attached (384_C-0831.eph.tar). The
  ephemeris files have been calculated for the requested
  observation period with a slight extension of a few days
  on both ends (25-Oct ...  31-Dec-2009) for the observatory
  code 309 (Paranal) with a 5 min time interval:
    date, time (UT), astrometric coordinates, topocentric
    apparent motions in right ascension (mu_alpha cos delta)
    and declination (mu_delta) in [arcsec/sec], the magnitude

Waiver Requests

```
No Waiver Request was submitted
```

Critical Observing Condition Constraints

Observations should be executed during stable observing
conditions with high accuracy calibration stability over
several hours, covering the calibration stars and
the W-H observations. Preferred airmass range: 1.0...1.5.

Time-Critical Aspects

The 9 observation blocks should be executed within about
one week in the time period 01-Nov-2009 to 20-Dec-2009 when
W-H reaches its maximum brightness (the time with the highest
predicted fluxes is around 20-Nov-2009). During that period
W-H is available for more than 2 hours each night at airmass
less than 1.5.

Special Execution Requirements

All 9 blocks should be executed preferentially within
one week (or as close in time as possible) to restrict
the changes in viewing geometry as much as possible
(aspect and phase angle as seen from Paranal).

Note: the target's apparent motion (as seen from VLT) is
      relatively high: between 182.9 and  271.4 arcsec/hour!

Special Calibration Information

The success of this programme depends on highly accurate
photometry. Observations of mid-IR stellar calibrators
should therefore take place before and after our W-H
observations, preferentially on nearby stars, close
in time, in AM and in the same instrument (0.075"/pix)
and filter (PAH1, SIV, NeII) settings.
In case that two such W-H observing blocks are executed
during one night, calibration measurements should also
take place between the two blocks.
The calibrators should cover the same airmass range
as the W-H observations.

ToO Information

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ToO Activators List

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Is this a Pre-imaging run ?

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false
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Pre-imaging Requirements

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Source(s) of Pre-imaging

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Pre-imaging sources not listed above

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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 ?

```
N/A
```

Do all your finding charts comply with both the general and instrument-specific Phase 2 Web Pages ?

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N/A
```

If you submitted OBs for standard stars, did you specify the magnitude and spectral type of all standard stars in the OBs ?

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N/A
```

Have you included OBs for any calibrations that you need but which are not part of the Calibration Plan ?

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N/A
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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 ?

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N/A
```

If this is a run that requires coordinated observations with other facilities, did you give proper instructions in the Time-Critical Aspects Section ?

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N/A
```

If the provided finding chart is at a different wavelength than the observations, did you clearly describe in the README file how to identify the target?

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N/A
```

Did you specify a guide star brighter than V=12mag within a field of r=5arcmin around the science target?

```
N/A
```

Last creation of page: Tue Oct 6 15:40:32 2009
If you have comments, please contact usd-help@eso.org