5831( 25) - 04/09/97 13:15 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 5831 Version: 25 Check-in Date: 09-Apr-1997 13:11:19 1.Proposal Title: Temporal Evolution of Neptune's Vertical Aerosol Structure ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle Solar System GO 5 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Heidi Hammel MASSACHUSETTS INSTITUTE OF TECHNOLOGY CoI: Wes Lockwood Lowell Observatory N ------------------------------------------------------------------------------------ 6. Abstract Neptune's atmosphere is extremely dynamic. Recently, an unprecedented change occurred in the planet's vertical aerosol structure - its northern hemisphere was seen to be brighter than its southern hemisphere for the first time since the advent of modern electronic detectors. We have HST time in Cycle 4 to observe Neptune (currently scheduled in October 1994), and will use that time to quantify the observed changes if they still exist. We request Cycle 5 time to follow up these observations and obtain new data on Neptune. We will determine a relaxation time for changes in vertical aerosol structure by observing Neptune at the same wavelengths as we did in Cycle 4, and will provide new vertical aerosol structure by obtaining new wavelength coverage to that scheduled for Cycle 4. Specifically, we propose to obtain images of Neptune with the Planetary Camera at wavelengths from 255 to 953 Angstroms. We will model the aerosol structure by measuring both the general center- to-limb behavior as a function of latitude, and the wavelength- dependent reflectivity of discrete features. If Neptune has changed yet again, we will study the new structure. The observations will be coordinated with our regular programs of groundbased imaging, photometry, and spectroscopy. In this way, the HST data will be tied directly to ground-based Neptune imaging taken over the past 8 years and the 21 -yr record of Neptune photometry from Lowell Observatory. ------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 2] Observations Description ------------------------ We request 4 exposures of Neptune with the WFPC2 in Planetary Camera mode in each of 9 visits. The exposures are divided into three blocks of 12 each, with the 12 exposures divided into three 4-exposure sets (3 blocks x 3 sets/block = 9 visits total). The 4 exposures in each set are F467M, F547M, FQCH4N-B, and FQCH4N-D. Block 1 (visits 1,2, 3) has 12 exposures divided into three 4- exposure sets, where each set contains an exposure through each of the filters. The start times of each of the three sets should be separated in time by 6 hours (to cover all Neptune longitudes). Block 2 (visits 4, 5, 6) is the same thing (three sets of 4 exposures each) starting one Neptune rotation (about 18 hours) after the beginning of block 1. This is to cover all longitudes again, to look for short-term temporal variations, and follow up on interesting features from Block 1. Block 3 (visits 7, 8, 9) is again the same, starting one month after beginning of block 1 (four weeks after beginning of block 1). This again will cover all longitudes, provide temporal coverage on the scale of a month, and yield good follow-up data to the previous two blocks. The blocks are structured to cover several of the different timescales of variability know to exist on Neptune (daily, weekly, monthly). Gaps will be covered by groundbased photometry and imaging, with these HST "snapshots" serving to periodically "sharpen" our blurry groundbased view. Real Time Justification ----------------------- Special Scheduling Requirement for timing: We request time near Neptune's opposition (July or August) because we will coordinate the HST observations with ground-based observing (imaging, photometry,and spectroscopy) at several sites. This will minimize the amount of HST time needed to characterize the atmosphere, and will provide more detailed understanding of Neptune by adding wavelengths which are not accessible to HST's Planetary Camera (e.g. the intermediate methane band at 7270 A, and some IR wavelengths). Through this coordination, the HST data can be tied into the ground-based Neptune imaging taken over the past 8 years and the 21-yr record of Neptune photometry from Lowell Observatory. Some funds will be requested for the PI to make the observations, and for minimal support of the data analysis. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: ------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 3] TARGET LIST b)Solar System Targets ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 1 | TARGET NAME: NEPTUNE ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: PLANET NEPTUNE ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | STD=NEPTUNE | | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | OLG OF NEPTUNE BETWEEN 320 40 | ------------------------------------------------------------------------------------------------------------------------------------ DATA | COMMENTS | V = 8.8 | THE WINDOW AROUND OPPOSITION (OLG F(4682.0)=3.51e-12 | NEAR 0) IS REQUESTED TO COORDINATE F(5454.0)=26.6e-13 | WITH GROUNDBASED OBSERVATIONS. IF F(6265.0)=3.77e-13 | THIS WINDOW IS UNAVAILABLE, THEN WE F(8940.0)=9.98e-14 | CAN RELAX THE CONSTRAINT SOMEWHAT. | CONTACT PI H. B. HAMMEL (MIT). | ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 11 | TARGET NAME: NEPTUNE-2 ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: PLANET NEPTUNE ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | STD=NEPTUNE | | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | ------------------------------------------------------------------------------------------------------------------------------------ DATA | COMMENTS | V = 8.8 | F(4682.0)=3.51e-12 | F(5454.0)=26.6e-13 | F(6265.0)=3.77e-13 | F(8940.0)=9.98e-14 | | ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 4] Visit: 01 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 800 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 5] Visit: 02 Visit Requirements: AFTER 01 BY 5.5 H TO 6.5 H On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 800 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 6] Visit: 03 Visit Requirements: AFTER 01 BY 11.5 H TO 12.5 H On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 800 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 7] Visit: 04 Visit Requirements: AFTER 01 BY 17.0 H TO 19.0 H On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 800 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 8] Visit: 05 Visit Requirements: AFTER 04 BY 5.5 H TO 6.5 H On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 800 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 9] Visit: 06 Visit Requirements: AFTER 04 BY 11.5 H TO 12.5 H On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 800 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 10] Visit: 07 Visit Requirements: AFTER 01 BY 50 D TO 90 D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 5 NEPTUNE WFPC2 IMAGE PC1 F410M 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 700 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 11] Visit: 08 Visit Requirements: AFTER 07 BY 5.5 H TO 6.5 H On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 5 NEPTUNE WFPC2 IMAGE PC1 F410M 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 700 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 12] Visit: 09 Visit Requirements: AFTER 07 BY 11.5 H TO 12.5 H On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 5 NEPTUNE WFPC2 IMAGE PC1 F410M 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 700 S 5 Comments: ;-------------------------------------------- - ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 13] Visit: 77 Visit Requirements: On Hold Comments: Additional Comments: Repeat of failed visit 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 NEPTUNE WFPC2 IMAGE PC1 F410M 1 100 S SEQ 5-40 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 700 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 14] Visit: 78 Visit Requirements: AFTER 77 BY 5.5 H TO 6.5 H On Hold Comments: Additional Comments: Repeat of failed visit 8. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 5 NEPTUNE WFPC2 IMAGE PC1 F410M 1 100 S SEQ 5-40 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 700 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 15] Visit: 79 Visit Requirements: AFTER 77 BY 11.25 H TO 12.75 H On Hold Comments: Additional Comments: Repeat of failed visit 9. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 5 NEPTUNE WFPC2 IMAGE PC1 F410M 1 100 S SEQ 5-40 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 10 NEPTUNE WFPC2 IMAGE PC1 F467M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 20 NEPTUNE WFPC2 IMAGE PC1 F547M 1 14 S ------------------------------------------------------------------------------------------------------------------------------------ 25 NEPTUNE WFPC2 IMAGE PC1 F953N 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 30 NEPTUNE WFPC2 IMAGE FQCH4N1 FQCH4N15 6211.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 40 NEPTUNE WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 700 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 5831( 25) - 04/09/97 13:15 - [ 16] Summary Form for Proposal 5831 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category Solar System ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements AFTER 01 BY 5.5 H TO 6.5 H AFTER 01 BY 11.5 H TO 12.5 H AFTER 01 BY 17.0 H TO 19.0 H AFTER 04 BY 5.5 H TO 6.5 H AFTER 04 BY 11.5 H TO 12.5 H AFTER 01 BY 50 D TO 90 D AFTER 07 BY 5.5 H TO 6.5 H AFTER 07 BY 11.5 H TO 12.5 H SEQ 5-40 NON-INT AFTER 77 BY 5.5 H TO 6.5 H AFTER 77 BY 11.25 H TO 12.75 H ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F467M F547M F953N FQCH4N15 FQCH4P15 F410M ------------------------------------------------------------------------------------------------------------------------------------ Target Names NEPTUNE ------------------------------------------------------------------------------------------------------------------------------------