8680( 5) - 05/04/00 10:21 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8680 Version: 5 Check-in Date: 04-May-2000 10:19:48 1.Proposal Title: The Asymmetric Atmosphere of Uranus ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 9 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Heidi Hammel Massachusetts Institute of Technology CoI: Dr. Kathy Rages Space Physics Research Institute N CoI: Dr. Wes Lockwood Lowell Observatory N CoI: Dr. Mark Marley New Mexico State University N ------------------------------------------------------------------------------------ 5. Abstract We propose to image Uranus as the planet plunges toward equinox in 2007. Recent HST images during this unique epoch (6818: Hammel, Lockwood, and Rages; 7429: Tomasko and Karkoschka; 7885: Hammel, Karkoschka, and Marley) have revealed: (i) strongly wavelength-dependent latitudinal structure, (ii) the presence of numerous visible- wavelength cloud features in the northern hemisphere, (iii) zonal winds which may deviate from the smooth profile implied by the Voyager observations in 1986, and, (iv) in the near-IR, discrete features northward of +25degrees\ that have the highest contrast ever seen for a Uranian cloud (Karkoschka 1998, Science 393, 765- 767; Hammel Etal 1999, submitted to Icarus). Specific scientific issues we will address with new observations are: whether the northern features are indicative of intrinsic change or result simply from a change of viewing angle; the shape and stability of the zonal wind profile; and the source of the as-yet unexplained variations of the atmospheric reflectivity. When possible, observations will be coordinated with ground-based imaging, spectroscopy, and photometry. This period approaching equinox is the first opportunity (in the era of modern instrumentation) to examine the far regions of the northern hemisphere on Uranus. ------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 2] Observations Description ------------------------ To fully map Uranus in longitude, four "samples" are required, separated in time by about 2 orbits (i.e., every third orbit). This spacing (every 288 minutes) will yield images at about roughly a quarter of the planet's atmospheric rotation period (about 18 hours on average = 1080 minutes). To have adequate baseline for the zonal wind measurements, two measurements of the same longitude are required separated by at least one (or preferably more than one) rotation. We cannot predict the longitudes of discrete features. Thus our total request is for two maps, i.e., 8 orbits. An orbital longitude constraint is applied to try to obtain Uranus observations near opposition on 12 August (NOT between 20 and 340). Uranus subtends more than 3.7 arcseconds then (compared to less than 3.5 arcsecondsbetween December and May). This constraint can be relaxed if scheduling is difficult. We hope to coordinate the HST observations with ground-based observing at several sites. We will being obtaining infrared spectroscopy at the NASA IRTF on 4-7 June 2000 with the new SpeX infrared spectrograph; we also have 3 half-nights with APO to do infrared imaging (schedule TBD but likely to be in late May 2000); and we will also be obtaining photometry at Lowell Observatory in this time period. If the HST images can be scheduled to be simultaneous or very close to the IRTF/APO/Lowell observations, this would greatly enhance the scientific return from all the observations by creating an extremely robust complementary data set (HST visible imaging, APO IR imaging, IRTF IR spectroscopy, and visible photometry which is directly tied to the long-term record). Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 3] TARGET LIST Solar System Targets ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 1 | TARGET NAME: URANUS ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: PLANET URANUS ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | STD=URANUS | | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | NOT OLG OF URANUS BETWEEN 60 340 | ------------------------------------------------------------------------------------------------------------------------------------ DATA | COMMENTS | V = 5.52 | Please schedule in EARLY JUNE 2000 B-V = 0.56 | if at all possible to coordinate U-B = 0.28 | with spectroscopy at the NASA IRTF | on 4-7 June. If that is not | feasible, earlier (Yr2000) is still | better. Contact PI H. B. Hammel for | info (203-438-3506, | hbh@alum.mit.edu). | ------------------------------------------------------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 4] Visit: 01 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Uranus Visit 1 - in EARLY JUNE 2000 if possible; SEQ NON-INT is NOT a hard requirement and can be weakened if there are scheduling difficulties Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 URANUS WFPC2 IMAGE PC1 F850LP 1 100 S SEQ 01-08 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 URANUS WFPC2 IMAGE PC1 F791W 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 3 URANUS WFPC2 IMAGE PC1 F658N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 4 URANUS WFPC2 IMAGE PC1 F953N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 5 URANUS WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 6 URANUS WFPC2 IMAGE PC1 F547M 1 10 S ------------------------------------------------------------------------------------------------------------------------------------ 7 URANUS WFPC2 IMAGE PC1 F467M 1 60 S ------------------------------------------------------------------------------------------------------------------------------------ 8 URANUS WFPC2 IMAGE FQCH4W2 FQCH4N 5433.0 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 5] Visit: 02 Visit Priority: Visit Requirements: AFTER 01 BY 4.3H TO 5.3H On Hold Comments: Additional Comments: Visit 2 = three orbits (4.8 hrs) after Visit 1; SEQ NON-INT is NOT a hard requirement and can be weakened if there are scheduling difficulties Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 URANUS WFPC2 IMAGE PC1 F850LP 1 100 S SEQ 01-10 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 URANUS WFPC2 IMAGE PC1 F791W 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 3 URANUS WFPC2 IMAGE PC1 F658N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 4 URANUS WFPC2 IMAGE PC1 F380W 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 5 URANUS WFPC2 IMAGE PC1 F631N 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 6 URANUS WFPC2 IMAGE FQCH4N1 FQCH4N15 6193.0 1 160 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 7 URANUS WFPC2 IMAGE PC1 F588N 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 8 URANUS WFPC2 IMAGE PC1 F336W 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 9 URANUS WFPC2 IMAGE PC1 F673N 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 10 URANUS WFPC2 IMAGE FQCH4W4 FQCH4N 7274.0 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 6] Visit: 03 Visit Priority: Visit Requirements: AFTER 01 BY 9.1H TO 10.1H On Hold Comments: Additional Comments: Visit 3 = six orbits (9.6 hrs) after Visit 1; SEQ NON-INT is NOT a hard requirement and can be weakened if there are scheduling difficulties Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 URANUS WFPC2 IMAGE PC1 F850LP 1 100 S SEQ 01-08 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 URANUS WFPC2 IMAGE PC1 F791W 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 3 URANUS WFPC2 IMAGE PC1 F658N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 4 URANUS WFPC2 IMAGE PC1 F380W 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 5 URANUS WFPC2 IMAGE PC1 F953N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 6 URANUS WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 7 URANUS WFPC2 IMAGE PC1 F439W 1 35 S ------------------------------------------------------------------------------------------------------------------------------------ 8 URANUS WFPC2 IMAGE PC1 F300W 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 7] Visit: 04 Visit Priority: Visit Requirements: AFTER 01 BY 13.9H TO 14.9H On Hold Comments: Additional Comments: Visit 4 = nine orbits (14.4 hrs) after Visit 1; SEQ NON-INT is NOT a hard requirement and can be weakened if there are scheduling difficulties Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 URANUS WFPC2 IMAGE PC1 F850LP 1 100 S SEQ 01-08 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 URANUS WFPC2 IMAGE PC1 F791W 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 3 URANUS WFPC2 IMAGE PC1 F658N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 4 URANUS WFPC2 IMAGE PC1 F380W 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 5 URANUS WFPC2 IMAGE PC1 F631N 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 6 URANUS WFPC2 IMAGE FQCH4N1 FQCH4N15 6193.0 1 160 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 7 URANUS WFPC2 IMAGE PC1 F588N 1 80 S ------------------------------------------------------------------------------------------------------------------------------------ 8 URANUS WFPC2 IMAGE PC1 F255W 1 400 S ------------------------------------------------------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 8] Visit: 05 Visit Priority: Visit Requirements: AFTER 01 BY 17.1H TO 18.1H On Hold Comments: Additional Comments: Visit 5 = eleven orbits (17.6 hrs) after Visit 1; SEQ NON-INT is NOT a hard requirement and can be weakened if there are scheduling difficulties Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 URANUS WFPC2 IMAGE PC1 F850LP 1 100 S SEQ 01-09 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 URANUS WFPC2 IMAGE PC1 F791W 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 3 URANUS WFPC2 IMAGE PC1 F658N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 4 URANUS WFPC2 IMAGE PC1 F380W 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 5 URANUS WFPC2 IMAGE PC1 F631N 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 6 URANUS WFPC2 IMAGE FQCH4N1 FQCH4N15 6193.0 1 160 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 7 URANUS WFPC2 IMAGE PC1 F588N 1 80 S ------------------------------------------------------------------------------------------------------------------------------------ 8 URANUS WFPC2 IMAGE PC1 F336W 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 9 URANUS WFPC2 IMAGE PC1 F255W 1 400 S ------------------------------------------------------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 9] Visit: 06 Visit Priority: Visit Requirements: AFTER 01 BY 21.7H TO 23.0H On Hold Comments: Additional Comments: Visit 6 = fourteen orbits (22.4 hrs) after Visit 1; SEQ NON-INT is NOT a hard requirement and can be weakened if there are scheduling difficulties Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 URANUS WFPC2 IMAGE PC1 F850LP 1 100 S SEQ 01-08 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 URANUS WFPC2 IMAGE PC1 F791W 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 3 URANUS WFPC2 IMAGE PC1 F658N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 4 URANUS WFPC2 IMAGE PC1 F380W 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 5 URANUS WFPC2 IMAGE PC1 F953N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 6 URANUS WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 7 URANUS WFPC2 IMAGE PC1 F439W 1 35 S ------------------------------------------------------------------------------------------------------------------------------------ 8 URANUS WFPC2 IMAGE PC1 F300W 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 10] Visit: 07 Visit Priority: Visit Requirements: AFTER 01 BY 26.6H TO 27.8H On Hold Comments: Additional Comments: Visit 7 = seventeen orbits (27.2 hrs) after Visit 1; SEQ NON-INT is NOT a hard requirement and can be weakened if there are scheduling difficulties Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 URANUS WFPC2 IMAGE PC1 F850LP 1 100 S SEQ 01-10 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 URANUS WFPC2 IMAGE PC1 F791W 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 3 URANUS WFPC2 IMAGE PC1 F658N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 4 URANUS WFPC2 IMAGE PC1 F380W 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 5 URANUS WFPC2 IMAGE PC1 F631N 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 6 URANUS WFPC2 IMAGE FQCH4N1 FQCH4N15 6193.0 1 160 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 7 URANUS WFPC2 IMAGE PC1 F588N 1 80 S ------------------------------------------------------------------------------------------------------------------------------------ 8 URANUS WFPC2 IMAGE PC1 F547M 1 10 S ------------------------------------------------------------------------------------------------------------------------------------ 9 URANUS WFPC2 IMAGE PC1 F467M 1 60 S ------------------------------------------------------------------------------------------------------------------------------------ 10 URANUS WFPC2 IMAGE FQCH4W2 FQCH4N 5433.0 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 11] Visit: 08 Visit Priority: Visit Requirements: AFTER 01 BY 31.4H TO 32.6H On Hold Comments: Additional Comments: Visit 8 = twenty orbits (32.0 hrs) after Visit 1; SEQ NON-INT is NOT a hard requirement and can be weakened if there are scheduling difficulties Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 URANUS WFPC2 IMAGE PC1 F850LP 1 100 S SEQ 01-07 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 URANUS WFPC2 IMAGE PC1 F791W 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 3 URANUS WFPC2 IMAGE PC1 F658N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 4 URANUS WFPC2 IMAGE PC1 F953N 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 5 URANUS WFPC2 IMAGE FQCH4P1 FQCH4P15 8922.0 1 400 S 5 ------------------------------------------------------------------------------------------------------------------------------------ 6 URANUS WFPC2 IMAGE PC1 F673N 1 100 S ------------------------------------------------------------------------------------------------------------------------------------ 7 URANUS WFPC2 IMAGE FQCH4W4 FQCH4N 7274.0 1 160 S ------------------------------------------------------------------------------------------------------------------------------------ 8680( 5) - 05/04/00 10:21 - [ 12] Summary Form for Proposal 8680 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PC1 FQCH4P15 FQCH4W2 FQCH4N15 FQCH4W4 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SEQ 01-08 NON-INT AFTER 01 BY 4.3H TO 5.3H SEQ 01-10 NON-INT AFTER 01 BY 9.1H TO 10.1H AFTER 01 BY 13.9H TO 14.9H AFTER 01 BY 17.1H TO 18.1H SEQ 01-09 NON-INT AFTER 01 BY 21.7H TO 23.0H AFTER 01 BY 26.6H TO 27.8H AFTER 01 BY 31.4H TO 32.6H SEQ 01-07 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F850LP F791W F658N F953N FQCH4P15 F547M F467M FQCH4N F380W F631N FQCH4N15 F588N F336W F673N F439W F300W F255W ------------------------------------------------------------------------------------------------------------------------------------ Target Names URANUS ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 8922.0 5433.0 6193.0 7274.0 ------------------------------------------------------------------------------------------------------------------------------------