Principal Investigator Email Address
emmanuel.lellouch@obspm.fr
Estimated Total Execution Time (hours, including overheads)
3.5
General Description
The goal of this proposal is to measure lines due to methane in Pluto spectrum from 1640.72 to 1679.32 nm with CRIRES. There is only 1 wavelength setup (free wavelength setup with reference wavelength 1665.9 nm). The target must be observed with AO, and at an airmass < 1.2, and at some periods only to ensure sufficient Doppler shift (see time-critical aspects). Pluto itself (R=13.6) will serve as AO guide star and SV guide star. Note that AO observations will reveal Pluto and Charon separately, separated by at most 1". Pluto (V~14, V-R ~ 0.6) is the brightest of the two, by about 2 magnitudes. To further facilitate the distinction of two bodies, the attached ephemeris gives their approximate V magnitude and the approximate RA,DEC offset of Charon with respect to Pluto. We will also provide daily finding charts in due time; they will be available for download on a private web page. In addition to the science target, one telluric standard must be observed at the same airmass as Pluto. We provide a list of five possible telluric standards, to be observed either just before or just after Pluto. The final choice of the star will depend on the precise observing dates/hours for Pluto, and possibly on the need to minimize the Moon proximity. The OBs are identical for all possible stars, and last 12min21 sec. Optimally, the 3.5 hour allocated to this program will be split in 2 equal parts of 1h45. For Pluto, we provide three OB: 1) MOV_Pluto-long and MOV_Pluto-long-2, which are identical and last 1h32min41sec each. Ideally, the observations should combine each of these Pluto OBs with one of the stars OB, for a total time of 3h30min02sec. 2) MOV_Pluto-short, lasting 1h18min50. This OB should be used only in case lack of time prevents the execution of MOV_Pluto-long or MOV_Pluto-long-2. Of course it should also be combined with one of the stars OB.
Waiver Requests
We have submitted and be granted waiver requests to: - use a free wavelength setting - use science OBs longer than 1 hour - not provide finding charts at this point.
Critical Observing Condition Constraints
Observations should always be performed at an airmass < 1.2. Clear conditions with a seeing better than 0.8" are required. The telluric standard observations should be made at the same airmass as Pluto.
Time-Critical Aspects
Due to the need of adequate Doppler shift, and to avoid the Moon proximity, the observations should be performed in one of the four "windows" below: From: To: 2008-04-28T00:00:00 2008-05-20T00:00:00 2008-07-20T18:00:00 2008-08-07T10:00:00 2008-08-08T15:00:00 2008-08-09T15:00:00 2008-08-14T15:00:00 2008-08-16T15:00:00
Special Execution Requirements
Each Pluto OB must be associated with one of the telluric stars OBs, to be performed at the same airmass.
Special Calibration Information
Each Pluto OB must be associated with one of the telluric stars OBs, to be performed at the same airmass. The telluric stars and their J2000 RA,DEC coordinates and H magnitudes are the following: hip 79404 16 12 18.2049 -27 55 34.939 mag_H 5.010 hip 87220 17 49 10.4762 -31 42 11.533 mag_H 4.786 hip 88116 17 59 47.5533 -23 48 58.081 mag_H 4.607 hip 91347 18 37 54.4261 -21 23 51.809 mag_H 5.436 hip 95619 19 26 56.4821 -29 44 35.611 mag_H 5.664 We also need standard flat fielding and daytime calibration.
ToO Information
ToO Activators List
Do the README file and the instrument comments of the telluric stars OBs include the required S/N/pixel of the spectrum of the telluric star, its spectral type and allowed spectral range?
N/A
Do any OBs include wavelength or flatfield calibrations?
If you are observing Moving Targets, have you attached suitable ephemeris files to your OBs?
If the slit viewer guide star is different from the target, are the RA and DEC offsets accurate to within 0.05 arcsec and do they take into account the relative proper motion between the two objects?
N/A
If you have preferences which OBs should be executed first for objects at similar RA, did you make use of the User Priority field in the OBs?