Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 1273c Report Date: 09-May-96:16:24 Version: ********** Check-in Date: ********** 1.Proposal Title: DETECTION OF WATER IN COMETS ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID SOLAR SYSTEM GTO/FOC Sub Category COMETS ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Cesare Barbieri PADOVA, UNIVERSITY OF ITALY 049-661499 PROFESSOR OF ASTRONO ------------------------------------------------------------------------------------ 7. Abstract It is proposed to detect the presence of water vapor in comets and to measure its production. Two methods will be used:a)the direct observation of water vapor absorption near 1650-1850 A; b)the observation of the emission of OH radicals directly produced into the A state after dissociation of their parent molecule, currently asumed to be H2O. The first method implies either to record the spectrum of a hot star when it is occulted by the vapor envelope or to record the spectrum of the sunlight reflected by the dust particles, after it has been partially absorbed by the atmosphere of the comet. The second method implies to map the OH* emission near 3080 A: OH radicals directly produced in the A state have a very different spatial distribution than those which fluoresce in the solar light. The detection will be attempted on comet P/Brorsen-Metcalf in July 1989. ------------------------------------------------------------------------------------ 8. Scientific Key Words: COMETS ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 4.00 par: 0 10. Num targs pri: 1 par: 0 ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 1273c PI: Cesare Barbieri Proposal Title: DETECTION OF WATER IN COMETS ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ J. L. Bertaux CNRS, AERONOMY SERVICE FRANCE X Cesare Barbieri PADOVA, UNIVERSITY OF ITALY X T. Encrenaz INSTITUTE OF ASTROPHYSICS, PARIS FRANCE X M. C. Festou INSTITUTE OF ASTROPHYSICS, PARIS FRANCE X ------------------------------------------------------------------------------------ 3. Description of proposed observations. A specific observation is proposed for Comet P/Brorsen-Metcalf in July 1989 (exposures in lines 30-32 in cycle 5). This comet is very active; we expect therefore a high dust production. For this reason we use both objective-prism and filter exposures. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. The ST is necessary: - to access the UV range - to have spatial resolution sufficient to detect anisotropies in the H2O ejection and discriminate between the OH* radicals from the regular OH radicals that fluoresce under solar excitation. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. special scheduling, in order to have both sufficient elongation from the Sun and proximity to perihelion. Preferred dates for Comet Brorsen Metcalf: Jul 22, 1989 +/- 7 days, before perihelion, for this very active comet. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. absolute calibration of the UV filters to measure the H2O production. Dark time for best sensitivity and photometric accuracy. ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. It is planned to spend the least amount of time at the STScI; final data reduction will be carried out at home Institution, where full support is available. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). PI and coworkers have access to all major image processing systems (Vaxes,MIDAS ,ASTRONET etc.) ------------------------------------------------------------------------------------ 13. It is proposed to detect the presence of water vapour in a periodic comet and to measure its production. Two methods can be used: a) the observation of water vapour absorption in the 1650-1850 band; b) the map of the dissociation product OH* near 3080 A. Prime target is P/Brorsen-Metcalf. ------------------------------------------------------------------------------------ 11. Address Information Page 3 Name: CESARE BARBIERI Category: PI Institution: INST. OF ASTRONOMY Address: VICOLO OSSERVATORIO 5 35100 City: PADOVA State: Zip Code: Country: ITALY Telephone: 049-661499 Telex (or e-mail): 430176 UNPADU I ------------------------------------------------------------------------------------ TARGET LIST b)Solar System Targets ID = 1273c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 1 | TARGET NAME: COMET-1979X ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: COMET BRADFIELD ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | TYPE = COMET, Q = 0.5871167, | E = 0.9672815, I = 162.2397156, | O = 58.1444397, W = 111.8489075, | T = 09-FEB-86:11:01:04, | EQUINOX=B1950, EPOCH=01-MAR-86. | | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | ------------------------------------------------------------------------------------------------------------------------------------ REF | DATA | COMMENTS | | 1 |SURF(V)=15+/-1 | FAST MOVING, COORD AT 09-FEB-86, | | UT=0.0, DELTA=0.83 VA, EQUINOX | | 1950.0 | ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 1273c [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 20 DEFINE # FOC/96 IMAGE 512X512 F307M 3080 1 20M 1 # H20-1 ------------------------------------------------------------------------------------------------------------------------------------ 21 ^ ^ ^ ^ ^ F278M 2780 ^ 30M ^ ------------------------------------------------------------------------------------------------------------------------------------ 22 DEFINE # ^ ^ ^ F231M 2320 ^ 50M ^ H20-2 ------------------------------------------------------------------------------------------------------------------------------------ 23 ^ ^ ^ ^ ^ F190M 1975 ^ 55M ^ ------------------------------------------------------------------------------------------------------------------------------------ 24 ^ ^ ^ ^ ^ F170M 1760 ^ 60M ^ ------------------------------------------------------------------------------------------------------------------------------------ 25 DEFINE # FOC/48 ^ ^ PRISM1 ^ 30M ^ H20-3 ------------------------------------------------------------------------------------------------------------------------------------ 26 ^ ^ FOC/48 ^ ^ PRISM2 ^ 40M ^ Comments: IT IS REQUESTED TO ACQUIRE AND TRACK THE COMETARY NUCLEUS FOR EVERY SEQUENCE. ------------------------------------------------------------------------------------------------------------------------------------ 30 USE H20 COMET-1979X 1 AT 22-JUL-90 +/- -3 7D SPATIAL SCAN SEQ 30-32 NO GAP CYCLE 2 / 30-32 ------------------------------------------------------------------------------------------------------------------------------------ 31 USE H20 COMET-1979X 1 -1 Comments: START SCAN, THEN TAKE EXPOSURE, THEN STOP SCAN ------------------------------------------------------------------------------------------------------------------------------------ 32 USE H20 COMET-1979X 3 SPATIAL SCAN -2 ------------------------------------------------------------------------------------------------------------------------------------ Scan Paramters Form Proposal ID: 1273c [ 6] ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 1 Exposure Logsheet lines: 30-32 FGS Scan: CONTINUOUS Dwell Only: dwell points/line: 0 Seconds per dwell: 0.00 Scan width (arc-secs): 0.0000 Scan length (arc-secs): 500.0000 Angle between sides (degrees) 0.00 Number of lines: 1 Scan rate (arc-sec/sec): 0.0270 PA of first scan line (degrees) 342.200 Scan frame (CEL or S/C): S/C Length Offset (arc-sec): 0.0000 Width Offset (arc-sec): 0.0000 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 1273c [ 7] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOC/96 ^ FOC/48 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ^ ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GTO/FOC ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 4.00 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category SOLAR SYSTEM ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category COMETS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements AT 22-JUL-90 +/- 7D; SPATIAL SCAN; SEQ 30-32 NO GAP; CYCLE 2 / 30-32 SPATIAL SCAN ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F307M F278M F231M F190M F170M PRISM1 PRISM2 ------------------------------------------------------------------------------------------------------------------------------------ Target Names COMET-1979X ------------------------------------------------------------------------------------------------------------------------------------