! $Id: 5329,v 5.1 1994/08/30 16:58:05 pepsa Exp $ coverpage: title_1: COORDINATED OBSERVATIONS OF NEPTUNE'S AEROSOLS: title_2: TEMPORAL, VERTICAL, AND HORIZONTAL VARIABLILTY CYCLE4 MEDIUM sci_cat: SOLAR SYSTEM sci_subcat: GIANT PLANETS proposal_for: GO longterm: 1 pi_fname: HEIDI pi_mi: B pi_lname: HAMMEL pi_inst: 2630 pi_country: USA pi_phone: 617-253-7568 hours_pri: 4.83 num_pri: 1 wf_pc: Y off_fname: DAVID off_lname: HARRIGAN off_title: ASSOC. DIRECTOR, OSP off_inst: 2630 off_addr_1: 77 MASSACHUSETTS AVE off_addr_2: E19-719 off_city: CAMBRIDGE off_state: MA off_zip: 02139 off_country: USA off_phone: 617-253-2495 ! end of coverpage abstract: line_1: We propose to obtain images of Neptune with WF/PC2 at wavelengths from line_2: 3327 to 8940 A, along with complementary groundbased observations: line_3: visible and IR imaging at the U.H. 2.2-m (HI), and Stromgren b and line_4: y photometry and methane-band spectra at Lowell Observatory (AZ). The line_5: data will be used to: model the current vertical aerosol structure by line_6: measuring the general center-to-limb behavior versus latitude; study line_7: the wavelength-dependent reflectivity of discrete features; measure line_8: the current distribution and number of discrete features; image the line_9: Great Dark Spot to provide a better estimate of its lifetime; and line_10: provide new measurements of atmospheric winds as a function of line_11: latitude. By being combined with groundbased data, HST data line_12: will be tied into the groundbased series of Neptune data taken by line_13: PI Hammel for the past 7 years and Co-I Lockwood for over 20 years. line_14: Simultaneous groundbased data were also obtained during the 1989 line_15: Voyager Encounter with Neptune; thus the observations proposed here line_16: will directly link HST Neptune observations to those obtained by line_17: Voyager 2. HST images will provide critical high-resolution line_18: observations, which along with the ground-based data will lead to line_19: unprecedented understanding of the temporal variations of Neptune's line_20: vertical aerosol structure and horizontal dynamics. ! ! end of abstract general_form_proposers: lname: HAMMEL fname: HEIDI mi: B inst: 2630 country: USA ! lname: LOCKWOOD fname: WES inst: 2540 country: USA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: (General descript here, detailed request in section 2.....) line_2: We request a total of 54 exposures. They should be divided into line_3: three blocks (for a total of 18 exposures per block). The purpose of line_4: a BLOCK is to take a snapshot of all longitudes on Neptune at a given line_5: point in time. The rotation period of Neptune varies with latitude, line_6: but typically is roughly 18 hours for the brightest cloud features. line_7: Therefore, to sample all longitudes, we need a snapshot at time X, a line_8: snapshot at time X+6 hours, and a snapshot at time X+12 hours. These line_9: separation times (6 hours and 12 hours) are approximate. The range of line_10: suitable separation times is about 5 to about 7 hours. line_11: Because we want to image Neptune at many wavelengths, each line_12: snapshot referred to above is actually going to be a SET of six line_13: exposures, one through each of six different filters. Hence a block line_14: is composed of three sets of six exposures (18 total). Every set is line_15: identical to every other set: simply acquire Neptune, and step through line_16: the six filters. line_17: We know from ground-based observations that variations in the line_18: atmosphere of Neptune occur on many timescales. The purpose of line_19: obtaining two more blocks is to try to characterize the time line_20: variability. The separations between the additional blocks is NOT line_22: critical; it is simply a recommendation to capture the most likely line_23: timescales of variation. ! question: 3 section: 2 line_1: Block 1 -- 18 exposures as described above, i.e. three sets of line_2: six exposures, each set roughly 6 hours after the previous set -- line_3: should be obtained at the first available time. line_4: Block 2 (18 exposures as described above) should start roughly line_5: a week after block 1. The precise start time of block 2 is NOT line_6: critical, but should be more than four days after block 1. line_7: Block 3 (18 exposures as described above) should start roughly line_8: fours weeks after block 1 (roughly a month). The precise start time line_9: of block 3 is NOT critical, but should be more than 10 days after line_10: block 2. ! question: 4 section: 1 line_1: Neptune's disk subtends at most 2.3 arcsec. The type of structure line_2: we want to resolve on Neptune (features and center-to-limb variations) line_3: typically have sizes corresponding to fractions of an arcsecond. line_4: Center-to-limb variations, in particular, are very dependent on the line_5: seeing. The highest contrast features have been resolved from the line_6: ground, and there is a rich history of groundbased observation. We line_7: propose to supplement the long-term groundbased data set with a series line_8: of very high resolution images. ! question: 5 section: 1 line_1: We will require special timing requirements to (1) image all line_2: longitudes on the planet, and (2) characterize the temporal line_3: variability of cloud structure. To satisfy the first condition, line_4: all six exposures in a set must be as close together in time as line_5: possible (but order is not important), and we will require three line_6: sets, one each at three rotational phases (three sets is a "block"). line_7: To address the second question, we will require two more series of line_8: observations at selected times after the first series. More details line_9: are provided in "Question 3 - Description of proposed observations." line_10: Also, we are requesting time near Neptune opposition to line_11: maximize the time available for obtaining the coordinating line_12: groundbased observations. ! ! question: 8 section: 1 line_1: We will be coordinating the HST observations with groundbased line_2: observing at several sites. This will minimize the amount of HST line_3: time needed to characterize the atmosphere, and will provide more line_4: detailed understanding of Neptune by adding wavelengths which are line_5: not accessible to HST (e.g. the intermediate methane band at 7270 A, line_6: and infrared wavelengths). Some funds will be requested for the PI line_7: to make the observations, and for minimal support of the data line_8: analysis. ! question: 9 section: 1 line_1: PI has never had HST time before. ! question: 10 section: 1 line_1: Existing computing facilities at MIT will be used for the data line_2: analysis. The computers, all linked through an ethernet network, line_3: include a DEC 5000, several smaller DEC workstations, numerous line_4: Macintosh workstations, and a variety of peripherals (including line_5: several laser printers, tape drives, optical disks, etc.). Supported line_6: software packages include IRAF and IDL. The MIT computer system line_7: provides access to the Internet and SPAN communications networks, line_8: with gateways to BITNET. line_9: MIT has a strong tradition of undergraduate participation in line_10: research, making funds available for support. There will likely line_11: be one or two undergraduates working with the PI on the project. line_12: Some graduate student assistance may also be desired. The PI's MIT line_13: position is a research staff appointment, so there are no anticipated line_14: conflicts with a teaching load. ! !end of general form text general_form_address: lname: Hammel fname: Heidi mi: B category: PI inst: 2630 addr_1: MIT 54-416 city: Cambridge state: MA zip: 02139 country: USA phone: 617-253-7568 telex: hbh@astron.mit.edu ! ! end of general_form_address records ! No fixed target records found solar_system_targets: targnum: 1 name_1: NEPTUNE descr_1: PLANET NEPTUNE lev1_1: STD = NEPTUNE wind_1: OLG OF NEPTUNE BETWEEN 320 40 comment_1: THE WINDOW AROUND OPPOSITION (OLG comment_2: NEAR 0) IS REQUESTED TO COORDINATE comment_3: WITH GROUNDBASED OBSERVATIONS. IF comment_4: THIS WINDOW IS STILL UNAVAILABLE comment_5: AFTER HST REFURBISHMENT, THEN WE comment_6: CAN RELAX THE CONSTRAINT SOMEWHAT. comment_7: CONTACT PI H. B. HAMMEL, AT MIT. fluxnum_1: 1 fluxval_1: V = 8.8 fluxnum_2: 2 fluxval_2: F(3327) = 1.50 E-12 fluxnum_3: 3 fluxval_3: F(4089) = 3.88 E-12 fluxnum_4: 4 fluxval_4: F(4682) = 3.51 E-12 fluxnum_5: 5 fluxval_5: F(5454) = 2.66 E-12 fluxnum_6: 6 fluxval_6: F(6265) = 3.77 E-13 fluxnum_7: 7 fluxval_7: F(8940) = 9.98 E-14 ! ! end of solar system targets ! No generic target records found exposure_logsheet: linenum: 5.010 sequence_1: DEFINE SET targname: NEPTUNE config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F336W num_exp: 1 time_per_exp: 140S s_to_n: 1000 fluxnum_1: 2 priority: 1 req_1: GROUP 5.01-5.06 NO GAP ! linenum: 5.020 sequence_1: DEFINE SET targname: NEPTUNE config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F410M num_exp: 1 time_per_exp: 70S s_to_n: 990 fluxnum_1: 3 priority: 1 ! linenum: 5.030 sequence_1: DEFINE SET targname: NEPTUNE config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F467M num_exp: 1 time_per_exp: 50S s_to_n: 1100 fluxnum_1: 4 priority: 1 ! linenum: 5.040 sequence_1: DEFINE SET targname: NEPTUNE config: WFPC2 opmode: IMAGE aperture: PC1 sp_element: F547M num_exp: 1 time_per_exp: 14S s_to_n: 1700 fluxnum_1: 5 priority: 1 ! linenum: 5.050 sequence_1: DEFINE SET targname: NEPTUNE config: WFPC2 opmode: IMAGE aperture: FQCH4N15 sp_element: FQCH4N15 wavelength: 6211 num_exp: 1 time_per_exp: 700S s_to_n: 1100 fluxnum_1: 6 priority: 1 ! linenum: 5.060 sequence_1: DEFINE SET targname: NEPTUNE config: WFPC2 opmode: IMAGE aperture: FQCH4P15 sp_element: FQCH4P15 wavelength: 8922 num_exp: 1 time_per_exp: 1400S s_to_n: 430 fluxnum_1: 7 priority: 1 ! linenum: 11.010 sequence_1: USE SET req_1: CYCLE 4 / 5.01 - 33.01; ! linenum: 12.010 sequence_1: USE SET req_1: AFTER 11.01 BY 6 H +/- 2 H ! linenum: 13.010 sequence_1: USE SET req_1: AFTER 11.01 BY 12 H +/- 2 H ! linenum: 21.010 sequence_1: USE SET req_1: AFTER 11.01 BY 7 D +/- 3 D ! linenum: 22.010 sequence_1: USE SET req_1: AFTER 21.01 BY 6 H +/- 2 H ! linenum: 23.010 sequence_1: USE SET req_1: AFTER 21.01 BY 12 H +/- 2 H ! linenum: 31.010 sequence_1: USE SET req_1: AFTER 11.01 BY 28 D +/- 8 D ! linenum: 32.010 sequence_1: USE SET req_1: AFTER 31.01 BY 6 H +/- 2 H ! linenum: 33.010 sequence_1: USE SET req_1: AFTER 31.01 BY 12 H +/- 2 H comment_1: WE HAVE TIMING REQUIREMENTS TO (1) comment_2: IMAGE ALL NEPTUNE LONGITUDES, AND comment_3: (2) STUDY TEMPORAL VARIATIONS. IF comment_4: HST CAN'T MEET THE REQUIREMENTS, comment_5: WE CAN RELAX THE CONSTRAINTS A BIT. comment_6: CONTACT PI H. B. HAMMEL, AT MIT. ! ! end of exposure logsheet ! No scan data records found