Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 1285c Report Date: 09-May-96:16:25 Version: ********** Check-in Date: ********** 1.Proposal Title: IO, EUROPA AND GANYMEDE BELOW 3000 A -- CYCLE 0 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID SOLAR SYSTEM GTO/OS Sub Category SATELLITES, RINGS ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone John J. Caldwell YORK UNIVERSITY CANADA (416)665-5449 PROFESSOR ------------------------------------------------------------------------------------ 7. Abstract Observe Io at eastern elongation with HRS G200M at SO_2 absorption feature. Observe Ganymede with identical exposure for calibration. L. Trafton/HRS will obtain a similar exposure of Io at the other orbital elongation. ------------------------------------------------------------------------------------ 8. Scientific Key Words: IO, EUROPA, GANYMEDE, SO2 ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 4.00 par: 0 10. Num targs pri: 3 par: 0 ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 1285c PI: John J. Caldwell Proposal Title: IO, EUROPA AND GANYMEDE BELOW 3000 A -- CYCLE 0 ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ John J. Caldwell YORK UNIVERSITY CANADA ------------------------------------------------------------------------------------ 3. Description of proposed observations. Additional exposures will be made in latter cycles. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. ST is required to do spectroscopy below 3000 A, where SO_2 has strong features. ST will improve significantly upon the S/N and spectral resolution achieved by previous satellite UV studies. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. The proposed observations must be made for both Io at both orbital elongations (including HRS/Trafton). Because each satellite has synchronous rotation with Jupiter, this insures that two independent hemispheres will be covered for each satellite. Previous studies of several kinds strongly suggest that there are significant hemispherical variations on Io. The orbital phase of Ganymede, (to be used as a calibrator) is not important. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. It is imperative to get a precise calibration, using the same instrument for the target and calibrator so that instrumental effects will not interfere with analysis. Since all the Galilean satellites are nearly the same size, Ganymede is ideal calibrator. If there is any variability in the solar spectrum at high resolution, contemporaneous observations of Ganymede will provide the best possible temporal calibration. ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. Io spectra will be reduced to albedos using Ganymede comparison spectra. Absorption features will be matched to laboratory SO_2 spectra obtained at essentially the same resolution as the ST data. Because of the thinness of the atmosphere of Io, it is probable that sophisticated radiative transfer techniques will not be required, but that will only be determined after initial data reduction. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. Io will be observed at one orbital elongation under this proposal with the HRS G200M grating. L.M. Trafton of the HRS team will make an identical observation of Io at the OTHER elongation, and we will combine our data for analysis. His program is entitled "SO_2 on Io" and line 2 therein is the relevant exposure. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). We have a dedicated Sun 4/280 computer for data analysis. ------------------------------------------------------------------------------------ 11. Address Information Page 3 Name: JOHN J. CALDWELL Category: PI Institution: YORK UNIVERSITY Address: PHYSICS DEPARTMENT 4700 KEELE STREET City: NORTH YORK State: ON Zip Code: M3J1P3 Country: CANADA Telephone: Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST b)Solar System Targets ID = 1285c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 1 | TARGET NAME: IO-EAST ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: SATELLITE IO ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | STD = JUPITER | STD = IO | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | OLG OF IO BETWEEN 63 117, | SEP OF IO CALLISTO FROM EARTH GT 12", | SEP OF IO EUROPA FROM EARTH GT 12", | SEP OF IO GANYMEDE FROM EARTH GT 12" | ------------------------------------------------------------------------------------------------------------------------------------ REF | DATA | COMMENTS | | 1 |V=5.0, TYPE=G8V | 2 |F(2200)=2E-14 | 3 |F(2116)=1E-14 | | ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 2 | TARGET NAME: GANYMEDE-CALIB ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: SATELLITE GANYMEDE ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | ^ | STD = GANYMEDE | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | OLG OF GANYMEDE BETWEEN 45 135 | SEP OF GANYMEDE CALLISTO FROM EARTH GT | 12", | SEP OF GANYMEDE EUROPA FROM EARTH GT | 12", | SEP OF GANYMEDE IO FROM EARTH GT 12" | ------------------------------------------------------------------------------------------------------------------------------------ REF | DATA | COMMENTS | | 1 |V=4.6, TYPE=G8V | GANYMEDE'S LEADING HEMISPHERE IS A 2 |F(2116)=9E-14 | FACTOR OF 2 BRIGHTER THAN THE 3 |F(2500)=24E-14 | TRAILING HEMISPHERE IN THE UV | ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 1285c [ 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 IO-EAST HRS ACQ 2.0 MIRROR-N2 SEARCH-SIZE=3 25S 1 1 ONBOARD ACQ FOR FAINT=1800 2 1.5-2.5 CYCLE 0 / 1-2.5 GROUP 1,8.2 WITHIN 8D Comments: STEP-TIME=1.0 ------------------------------------------------------------------------------------------------------------------------------------ 1.5 IO-EAST HRS ACQ 2.0 MIRROR-N2 SEARCH-SIZE=1 1 265S 1 1 ONBOARD ACQ FOR 2 LOCATE=NO 2 SEQ 1-1.5 NON-INT FAINT=0 MAP=END-POINT Comments: STEP-TIME=1.0 ------------------------------------------------------------------------------------------------------------------------------------ 1.9 WAVE HRS ACCUM SC1 G200M 2116 FP-SPLIT=STD 1 57.6S 1 CALIB FOR 2 ------------------------------------------------------------------------------------------------------------------------------------ 2 IO-EAST HRS ACCUM 2.0 G200M 2116 FP-SPLIT=STD 4 15M 15 3 2 Comments: IF IT WOULD HELP SCHEDULING EFFICIENCY TO HAVE MORE BUT SHORTER EXPOSURES (E.G. 4 X 15, OR 6 X 10), OKAY. ------------------------------------------------------------------------------------------------------------------------------------ 2.5 IO-EAST HRS IMAGE 2.0 MIRROR-N2 NX=16 1 256S 20 1 1 SEQ 2.0-2.5 NO GAP NY=16 Comments: STEP-TIME=1.0 ------------------------------------------------------------------------------------------------------------------------------------ 8.2 GANYMEDE- HRS ACQ 2.0 MIRROR-N2 SEARCH-SIZE=5 1 5S 1 1 ONBOARD ACQ FOR CALIB FAINT=600 8.3-8.6 CYCLE 0 / 8.2-8.6 SEQ 8.2-8.3 NON- INT ------------------------------------------------------------------------------------------------------------------------------------ 8.3 GANYMEDE- HRS ACQ 2.0 MIRROR-N2 SEARCH-SIZE=1 1 52.8S 1 1 ONBOARD ACQ FOR CALIB FAINT=0 8.5 LOCATE=NO MAP=END-POINT ------------------------------------------------------------------------------------------------------------------------------------ 8.4 WAVE HRS ACCUM SC1 G200M 2116 FP-SPLIT=STD 1 57.6S 1 CALIB FOR 8.5 ------------------------------------------------------------------------------------------------------------------------------------ 8.5 GANYMEDE- HRS ACCUM 2.0 G200M 2116 FP-SPLIT=STD 4 15M 70 2 2 CALIB Comments: SAME COMMENT AS FOR LINE 2 ------------------------------------------------------------------------------------------------------------------------------------ 8.6 GANYMEDE- HRS IMAGE 2.0 MIRROR-N2 NX=16 1 51.2S 15 1 1 SEQ 8.5-8.6 NO GAP CALIB NY=16 Comments: STEP-TIME=0.2 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 1285c [ 6] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACCUM IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SEARCH-SIZE FAINT LOCATE=NO MAP FP-SPLIT=STD NX=16 NY=16 FAINT LOCATE ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GTO/OS ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 4.00 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category SOLAR SYSTEM ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category SATELLITES, RINGS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 1.5-2.5; CYCLE 0 / 1-2.5; GROUP 1,8.2 WITHIN 8D ONBOARD ACQ FOR 2; SEQ 1-1.5 NON-INT; CALIB FOR 2; SEQ 2.0-2.5 NO GAP ; ONBOARD ACQ FOR 8.3-8.6; CYCLE 0 / 8.2-8.6; SEQ 8.2-8.3 NON-INT; ONBOARD ACQ FOR 8.5; CALIB FOR 8.5; SEQ 8.5-8.6 NO GAP; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR-N2 G200M ------------------------------------------------------------------------------------------------------------------------------------ Target Names IO-EAST GANYMEDE-CALIB ------------------------------------------------------------------------------------------------------------------------------------