7583( 6) - 01/29/98 16:17 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 7583 Version: 6 Check-in Date: 29-Jan-1998 16:16:03 1.Proposal Title: Spatial & Temporal Variations in the UV Emission from the Atmosphere of Io ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GTO/STIS 7 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: FRED ROESLER UNIVERSITY OF WISCONSIN CoI: Warren Moos The Johns Hopkins University N CoI: Paul Feldman The Johns Hopkins University N CoI: Doyle Hall University of Colorado N CoI: Melissa McGrath Space Telescope Science Institute N CoI: Ron Oliversen Goddard Space Flight Center N CoI: Frank Scherb University of Wisconsin N CoI: Darrell Strobel The Johns Hopkins University N CoI: Carey Woodward University of Wisconsin N CoI: Kurt Retherford The Johns Hopkins University Y ------------------------------------------------------------------------------------ 5. Abstract Measurements of the spatial distribution of Io's hydrogen, sulfur and oxygen FUV emissions will be obtained using STIS spectroscopic and imaging modes. This coordinated program uses 10 orbits of STIS GTO time, 5 orbits from PI W. Moos (program 7582) and 5 orbits from PI F. Roesler (prog. 7583). During Visit 1, MAMA FUV spectroscopy and imaging will be performed when Io is west of Jupiter. Visit 2 will perform MAMA FUV spectroscopy when Io is east of Jupiter. Visit 3 is devoted to emission line measurements of the spatial and velocity distribution of the atomic oxygen doublet OI 1356A/1359A and the atomic sulfur multiplet SI 1479A. TIME-TAG mode is used for all observations to monitor the temporal variability of the emissions. ------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 2] Observations Description ------------------------ The Moos/Roesler 1998 STIS GTO program to observe Io is a 3-visit, 10-orbit program designed to measure the satellite's FUV emissions. Visit 1 will observe Io near western elongation using 4 HST orbits: a DIFFUSE acquisition (no peakup required), followed by 1 orbit of MAMA G140L TIME-TAG imaging, the first half with a longpass filter >1300A, the second half without, then ending with 3 orbits of MAMA G140L 52X2 TIME-TAG spectroscopy. Visit 2 will observe Io near eastern elongation using 2 HST orbits: an acquisition followed by 2 orbits of MAMA G140L 52X2 TIME-TAG spectroscopy. Visit 3 will observe Io near western elongation using 4 HST orbits: an acquisition followed by 2 orbits each for MAMA G140M TIME-TAG spectroscopy in the OI 1356A/1359A emission doublet and the SI 1479A multiplet. We request that the observations be scheduled close to Jupiter opposition to minimize terrestrial airglow and geocoronal Lyman alpha line emission contamination in visit 1 and visit 2. We also request that visit 1 and visit 2 occur at consecutive Io elongations. However, if HST/Io scheduling constraints make these requests difficult, they may be relaxed as necessary. Here is the order of decreasing scheduling priorities: visit 1 and 2 within specified Jupiter OLG window, visit 1 and 2 at consecutive Io elongations (within the same week or so would suffice), visit 3 close to the preferred time window for visits 1 and 2. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: DAT Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 3] TARGET LIST b)Solar System Targets ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 1 | TARGET NAME: IO-WEST-1 ------------------------------------------------------------------------------------------------------------------------------------ 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 195 345, OLG OF | JUPITER BETWEEN 323 24 | ------------------------------------------------------------------------------------------------------------------------------------ DATA | COMMENTS | V = 5.02 | Io on Jupiter's west (dusk) side. B-V = 1.17 | The other galilean satellites must | be separated by more than 10 arcsec | from the target (by default). Here | we have made the orbital longitude | (OLG) window centered at the | elongation point +/- 75 degrees to | separate Jupiter from the target. We | prefer the ranges of 195 to 245 or | 270 to 345 but won't further | constrain the scheduling for this. | ------------------------------------------------------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 4] TARGET LIST b)Solar System Targets ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 2 | TARGET NAME: IO-EAST-1 ------------------------------------------------------------------------------------------------------------------------------------ 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 15 165, OLG OF JUPITER | BETWEEN 323 24 | ------------------------------------------------------------------------------------------------------------------------------------ DATA | COMMENTS | V = 5.02 | Io on Jupiter's east (dawn) side. B-V = 1.17 | The other galilean satellites must | be separated by more than 10 arcsec | from the target (by default). Here | we have made the orbital longitude | (OLG) window centered at the | elongation point +/- 75 degrees to | separate Jupiter from the target. | ------------------------------------------------------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 5] TARGET LIST b)Solar System Targets ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 3 | TARGET NAME: IO-WEST-2 ------------------------------------------------------------------------------------------------------------------------------------ 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 195 345, OLG OF | JUPITER BETWEEN 297 24 | ------------------------------------------------------------------------------------------------------------------------------------ DATA | COMMENTS | V = 5.02 | Io is on Jupiter's west (dusk) side. B-V = 1.17 | The other galilean satellites must | be separated by more than 10 arcsec | from the target (by default). Here | we have made the orbital longitude | (OLG) window centered at the | elongation point +/- 75 degrees to | separate Jupiter from the target. We | prefer the ranges of 195 to 245 or | 270 to 345 but won't further | constrain the scheduling for this. | ------------------------------------------------------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 6] Visit: 01 Visit Priority: Visit Requirements: GROUP 01,02 WITHIN 7 D GROUP 01,02,03 WITHIN 100 D On Hold Comments: Additional Comments: Visit 1 must observe Io west of Jupiter in the period specified near Jupiter opposition. This ensures that the duration of each orbit's SHADOW interval is near its maximum for Jupiter observations, minimizing terrestrial airglow contamination. The first orbit of this visit is split into a filtered imaging exposure and a non-filtered imaging exposure. The three following orbits are split into two exposures each due to moving target limitations. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 IO-WEST-1 STIS/C ACQ F28X50L MIRROR ACQTYPE=DIFFUSE, 1 0.1 S ONBOARD ACQ FOR 4,5,6,7,8 CD P DIFFUSE-CENTER=GEOMETRIC-CENTER, ,9 CHECKBOX=25 Comments: Io is a V=5 solar-type source, and its disk projects a diameter between 1.23 and 1.27 arcsec over the requested observation window. A DIFFUSE ACQ with CHECKBOX=25 (1.27 arcsec) with no PEAK-UP is an appropriate choice for these observations that use the 52X2 slit. A previous acquisition using the F28X50LP filter and performed when Io's apparent diameter was 1.16 arcsec produced a maximum 1.1e4 DN/px for a 0.1 second CCD exposure using the default GAIN of 4. This is roughly a factor of three smaller than the CCD saturation limit of 3.6e4 DN/px. During this CCD exposure centered on Io, 3.2e6 DN were accumulated within the brightest checkbox, providing an adequate signal-to-noise ratio for DIFFUSE acquisitions. ------------------------------------------------------------------------------------------------------------------------------------ 2 IO-WEST-1 STIS/F TIME-TA F25SRF2 MIRROR BUFFER-TIME=3000 1 15.25 M UV-MAM G A Comments: The F25SRF2 strontium fluoride filter provides a long bandpass >1280A, blocking the geocoronal lyman alpha feature. Imaging from 1280A-1700A ------------------------------------------------------------------------------------------------------------------------------------ 3 IO-WEST-1 STIS/F TIME-TA 25MAMA MIRROR BUFFER-TIME=500 1 500 S UV-MAM G A Comments: Non-filtered imaging from 1150A-1700A. ------------------------------------------------------------------------------------------------------------------------------------ 4 IO-WEST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=1700 1 1300 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 7] Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 5 IO-WEST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=1700 1 1300 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 6 IO-WEST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=1700 1 1200 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 7 IO-WEST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=1700 1 1200 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 8 IO-WEST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=1700 1 1150 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 9 IO-WEST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=1700 1 1150 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 8] Visit: 02 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Visit 2 must observe Io east of Jupiter in the period specified near Jupiter opposition. This ensures that the duration of each orbit's SHADOW interval is near its maximum for Jupiter observations, minimizing airglow contamination. The orbits are split into two exposures each due to moving target limitations. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 IO-EAST-1 STIS/C ACQ F28X50L MIRROR ACQTYPE=DIFFUSE, 1 0.1 S ONBOARD ACQ FOR 11,12,13, CD P DIFFUSE-CENTER=GEOMETRIC-CENTER, 14 CHECKBOX=25 Comments: Io is a V=5 solar-type source, and its disk projects a diameter between 1.23 and 1.27 arcsec over the requested observation window. A DIFFUSE ACQ with CHECKBOX=25 (1.27 arcsec) with no PEAK-UP is an appropriate choice for these observations that use the 52X2 slit. A previous acquisition using the F28X50LP filter and performed when Io's apparent diameter was 1.16 arcsec produced a maximum 1.1e4 DN/px for a 0.1 second CCD exposure using the default GAIN of 4. This is roughly a factor of three smaller than the CCD saturation limit of 3.6e4 DN/px. During this CCD exposure centered on Io, 3.2e6 DN were accumulated within the brightest checkbox, providing an adequate signal-to-noise ratio for DIFFUSE acquisitions. ------------------------------------------------------------------------------------------------------------------------------------ 11 IO-EAST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=2000 1 15.5 M UV-MAM G A Comments: The central wavelength of 1425A provides coverage over the 1150-1730A spectral range. ------------------------------------------------------------------------------------------------------------------------------------ 12 IO-EAST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=2000 1 15.25 M UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 13 IO-EAST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=2000 1 1205 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 14 IO-EAST-1 STIS/F TIME-TA 52X2 G140L 1425 BUFFER-TIME=2000 1 1205 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 9] Visit: 03 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Visit 3 must observe Io west of Jupiter. The orbits are split into two exposures each due to moving target limitations. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 20 IO-WEST-2 STIS/C ACQ F28X50L MIRROR ACQTYPE=DIFFUSE, 1 0.1 S ONBOARD ACQ FOR 21,22,23, CD P DIFFUSE-CENTER=GEOMETRIC-CENTER, 24,25,26,27,28 CHECKBOX=25 Comments: Io is a V=5 solar-type source, and its disk projects a diameter between 1.23 and 1.27 arcsec over the requested observation window. A DIFFUSE ACQ with CHECKBOX=25 (1.27 arcsec) with no PEAK-UP is an appropriate choice for these observations that use the 52X2 slit. A previous acquisition using the F28X50LP filter and performed when Io's apparent diameter was 1.16 arcsec produced a maximum 1.1e4 DN/px for a 0.1 second CCD exposure using the default GAIN of 4. This is roughly a factor of three smaller than the CCD saturation limit of 3.6e4 DN/px. During this CCD exposure centered on Io, 3.2e6 DN were accumulated within the brightest checkbox, providing an adequate signal-to-noise ratio for DIFFUSE acquisitions. ------------------------------------------------------------------------------------------------------------------------------------ 21 IO-WEST-2 STIS/F TIME-TA 52X2 G140M 1371 BUFFER-TIME=4000 1 15 M UV-MAM G A Comments: The central wavelength of 1371A provides coverage over the 1344-1398A spectral range. ------------------------------------------------------------------------------------------------------------------------------------ 22 IO-WEST-2 STIS/F TIME-TA 52X2 G140M 1371 BUFFER-TIME=4000 1 920 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 23 IO-WEST-2 STIS/F TIME-TA 52X2 G140M 1371 BUFFER-TIME=4000 1 1200 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 24 IO-WEST-2 STIS/F TIME-TA 52X2 G140M 1371 BUFFER-TIME=4000 1 19.75 M UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 25 IO-WEST-2 STIS/F TIME-TA 52X2 G140M 1470 BUFFER-TIME=4000 1 1155 S UV-MAM G A Comments: The central wavelength of 1470A provides coverage over the 1443-1497A spectral range. ------------------------------------------------------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 10] Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 26 IO-WEST-2 STIS/F TIME-TA 52X2 G140M 1470 BUFFER-TIME=4000 1 1155 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 27 IO-WEST-2 STIS/F TIME-TA 52X2 G140M 1470 BUFFER-TIME=4000 1 1145 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 28 IO-WEST-2 STIS/F TIME-TA 52X2 G140M 1470 BUFFER-TIME=4000 1 1145 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 7583( 6) - 01/29/98 16:17 - [ 11] Summary Form for Proposal 7583 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ TIME-TAG ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ACQTYPE=DIFFUSE DIFFUSE-CENTER=GEOMETRIC-CENTER CHECKBOX=25 BUFFER-TIME=3000 BUFFER-TIME=500 BUFFER-TIME=1700 BUFFER-TIME=2000 BUFFER-TIME=4000 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GTO/STIS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GROUP 01,02 WITHIN 7 D GROUP 01,02,03 WITHIN 100 D ONBOARD ACQ FOR 4,5,6,7,8,9 ONBOARD ACQ FOR 11,12,13,14 ONBOARD ACQ FOR 21,22,23,24,25,26,27,28 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G140L G140M ------------------------------------------------------------------------------------------------------------------------------------ Target Names IO-WEST-1 IO-EAST-1 IO-WEST-2 ------------------------------------------------------------------------------------------------------------------------------------