0 Assigned ID: 5610 ----- Attempting Submission 1 (Tue Mar 26 20:17:27 GMT 2024) ----- A target acquisition should probably be performed before doing spectroscopy or coronography with STIS or COS. A target acquisition should probably be performed before doing spectroscopy or coronography with STIS or COS. SAME POS MAY NOT BE APPROPRIATE 2024-10-04: Adjustment of target position on detector POSTARG keywords and by replacing D1 apertures with regular apertures. We do not do acquisitions for the spectral observations. For the slitless exposure exact pointing is not required at all. For the long-slit exposures with the 0.5 arcec slit, even with an offset of up to 1 arcec along x the slit will still intersect with a good fraction of the Uranus' 3.6 arcsec wide disk. I have used BUFFER-TIMES of 600 seconds now. These might need to be decreased for the imaging observations. 2024-09-04: Buffer times reduced to 200 secs for slitlesss and clear filter imaging. 2052855939 ----- Attempting Submission 1 (Fri Jul 12 14:55:28 GMT 2024) ----- ----- Attempting Submission 2 (Wed Sep 04 07:48:12 GMT 2024) ----- ----- Attempting Submission 3 (Fri Oct 04 12:16:52 GMT 2024) ----- Acquisitions are not included as explained in the submission comments. The upper atmospheres of giant planets play key role in various processes such as solar wind interaction, atmospheric escape, magnetosphere-ionosphere coupling, and interaction with ring particles. Voyager2 revealed a largely extended upper atmosphere of Uranus, devoid of hydrocarbons - unique among the solar system's giant planets. It is not yet well understood how the upper atmosphere varies seasonally and Uranus' orbital period of 84 years makes it generally difficult to obtain observational evidence for seasonal changes. However, IR monitoring of ionospheric H3+ emissions suggest a decrease in temperature of the ionized upper atmosphere since 1992. The abundance of H, H2 and H3+ in the upper atmosphere are strongly coupled and indeed HST Ly-alpha observations before (1998) and close to equinox (2011) revealed a similar trend with shrinking and decreasing emissions. Imaging the H Ly-alpha emissions from Uranus with STIS now in cycle 32 - more than a decade after equinox - offers the unique possibility to test the puzzling cooling trend. The new STIS Ly-alpha images together with the archived STIS images will determine if Uranus' neutral upper atmosphere is indeed undergoing continuous cooling. Additional STIS G140M slit spectra provide precise measurements of Raman shifted features for a characterization of the H2 component. With only 8 orbits in 2024 this program will complete a unique archive of FUV data on the only ice giant planet with Ly-alpha emission signal observable from Earth and inform a possible large Uranus Orbiter and Probe mission as recommended by the NASA decadal survey. The idea is to take different kind of imaging and spectral observations combined in one visit to compare the signals and calibrate archival observations of similar type (but never simultanously taken). First we want a global image of only Lyman-alpha emissions through slit-less spectral imaging with G140L and the FUV-MAMA Then we take a long-slit spectrum to get Raman-shifted Lyman-alpha photons longward of the Lyman-alpha line. And finally, we take an image pair with the clear filter (FUV-MAMA) and the S25SRF2 filter. The difference of these two should also give a Lyman-alpha image but with some uncertainty from the throughput dependncy. For our two visits these filter pairs can be calibrated for the first time with the G140L Lyman-alpha image. We do not do acquisitions for the spectral observations. For the slitless exposure exact pointing is not required at all. For the long-slit exposures with the 0.5 arcec slit, even with an offset of up to 1 arcec along x the slit will still intersect with a good fraction of the Uranus' 3.6 arcsec wide disk. One of the visits should optimally happen simultaneously to the observations by JWST from program 5073. The team is composed of experts on different parts of the project from planing of the observations to data analysis and modeling for the interpretation. The PI Lorenz Roth has experience from leading eight successful HST programs as PI and is currently leading a small program in Cycle 28. He has successfully led the previous HST observing programs from beginning to completion with publications. CoI Laurent Lamy is an experienced HST Uranus observer with three program involving Uranus as PI. CoI Henrik Melin is leading expert on the H3+ observations of Uranus, providing the ionosphere context for the analysis. Randy Gladstone is an expert in radiative transfer in the upper atmospheres of giant planets. He has developed a numerical code for resonance line radiative transfer for Jupiter, which has been applied to Uranus as well and will be used for the more detailed analysis. Darrell Strobel is a planetary aeronomer, who was involved in the Voyager UVS observations of Uranus and will support the interpretation through analytical calculations. Ivchenko is an experencied aurora observer and was involved in several previous HST campaigns as CoI. Solar System Astronomy 6 false false true false false false false false SUPPORTED SOLAR SYSTEM YES PLANET Planet Uranus STD=URANUS EARTH STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/FUV-MAMA Spectroscopic No No G140M 1272 STIS/FUV-MAMA Imaging No No 25MAMA STIS/FUV-MAMA Imaging No No F25SRF2 1725435953797 Using ephemeris for target 17737-01-URANUS ephemeris data for target 17737-01-URANUS does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 24.214 to 26.089. ephemeris interval: 24.244 to 26.244 The scheduling data was generated by CASM 32.1.3. CASM was run in Phase II mode. 1727841943000 242.73218713010368 (Tic-Visit :proposal-id 17737 :visit-id "01" :proposal-version -1 :trans-version "20240627" :date "04-Sep-2024 09:45:53.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 2052592 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17737 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17737 :visit-id "01" :orbit-number 1 :pcs-time 380 :si-vis-utilization 1976 :al-overhead-at-end 0 :internal-dur-at-end 2665 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2645 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17737 :visit-id "01" :orbit-number 2 :pcs-time 380 :si-vis-utilization 2265 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2645 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17737 :visit-id "01" :orbit-number 3 :pcs-time 380 :si-vis-utilization 2265 :al-overhead-at-end 0 :internal-dur-at-end 178 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2645 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17737 :visit-id "01" :orbit-number 4 :pcs-time 380 :si-vis-utilization 2265 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2645 :pcs-gap 0 ) true 4 0 1728044191864 Using ephemeris for target 17737-02-URANUS ephemeris data for target 17737-02-URANUS does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 24.246 to 26.089. ephemeris interval: 24.274 to 26.274 The scheduling data was generated by CASM 32.1.3. CASM was run in Phase II mode. /private/var/folders/fr/ljn5s3656bjff7r45qp4cw340000gn/T/OPVisit4516968229378196744.xml (Tic-Visit :proposal-id 17737 :visit-id "02" :proposal-version -1 :trans-version "20240627" :date "04-Oct-2024 14:16:31.0" :trans-errors '(:WARNINGS 1 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 2052592 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17737 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17737 :visit-id "02" :orbit-number 1 :pcs-time 380 :si-vis-utilization 1976 :al-overhead-at-end 0 :internal-dur-at-end 2665 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2645 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17737 :visit-id "02" :orbit-number 2 :pcs-time 380 :si-vis-utilization 2263 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2645 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17737 :visit-id "02" :orbit-number 3 :pcs-time 380 :si-vis-utilization 2262 :al-overhead-at-end 0 :internal-dur-at-end 178 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2645 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17737 :visit-id "02" :orbit-number 4 :pcs-time 380 :si-vis-utilization 2245 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2645 :pcs-gap 0 ) true 4 0