From: IN%"KTOBISKA@gllsvc.jpl.nasa.gov" 13-DEC-1996 07:01:04.38 To: IN%"MARIE.L.SLONSKI@JPL.NASA.gov" CC: IN%"knaviaux@gllsvc.jpl.nasa.gov", IN%"jaiello@gllsvc.jpl.nasa.gov", IN%"stephens@gllsvc.jpl.nasa.gov", IN%"jajello@jpluvs.jpl.nasa.gov", IN%"simmons@pisces.colorado.edu", IN%"pryor@pisces.colorado.edu", IN%"stewart@pisces.colorado.edu" Subj: E4 UVS science summary Return-path: Received: from glvax1.jpl.nasa.gov by pisces.colorado.edu (PMDF V4.2-13 #12962) id <01ICYAXN4W9C9GVCJQ@pisces.colorado.edu>; Fri, 13 Dec 1996 07:00:38 GMT Date: Thu, 12 Dec 1996 22:58:45 -0800 From: KTOBISKA@gllsvc.jpl.nasa.gov Subject: E4 UVS science summary To: MARIE.L.SLONSKI@JPL.NASA.gov Cc: knaviaux@gllsvc.jpl.nasa.gov, jaiello@gllsvc.jpl.nasa.gov, stephens@gllsvc.jpl.nasa.gov, jajello@jpluvs.jpl.nasa.gov, simmons@pisces.colorado.edu, pryor@pisces.colorado.edu, stewart@pisces.colorado.edu Message-id: <961212225845.22800f8c@gllsvc.jpl.nasa.gov> Content-transfer-encoding: 7BIT X-Vmsmail-To: MARIE.L.SLONSKI@JPL.NASA.GOV X-Vmsmail-Cc: @GLLSVC$USER:[KTOBISKA]JPLUVS,KTOBISKA UVS AWG: The top priority UVS Jupiter atmospheric observation during this orbit is a realtime far- and mid-ultraviolet (FUV/MUV: 115-320 nm) high solar phase angle (148 to 160 deg) hot spot feature track observation (FTKH1EX). In order to obtain this observation unattainable from Earth, the AWG executes an 80 degree science turn. Analysis of the data will result in a unique data set of stratospheric aerosol scattering properties at high solar phase angles. Additional hot spot feature track realtime observations (3 emission angles at 55 deg solar phase angle - FTKR1EX) will be performed in conjunction with other AWG instruments. Independent UVS atmospheric observations will provide a realtime fixed local time map for global FUV spectral coverage and energy budget measurements during 1 Jovian rotation on the equatorial brightside (FIXTMB). Realtime global mapping of equatorial H Lyman-alpha on the darkside will continue as in previous orbits to obtain hydrogen distribution maps without the influence of direct solar radiation (FIXLON). Realtime southern auroral full spectral FUV observations will provide longitudinal coverage during part of a Jupiter rotation on both the dayside and nightside (AURMAP). Analysis of the ratios between different spectral lines (color ratios) will yield energies of the electrons that are precipitating into the auroral zones. UVS MWG: The highest priority UVS magnetospheric observations during this orbit will be those of the Io torus in conjunction with the EUV instrument (both pointed perpendicular to the spacecraft). This 10-hour set of E4-inbound torus measurements at the beginning of the E4A encounter period (E4NANS) completes the Io torus observations begun during C3C, and will map the torus noon ansa in S and O emission lines using UVS FUV and MUV wavelengths simul- taneously with the EUV. Ratios of emission lines will determine electron temperatures. There are no UVS or EUV science observations during E4 cruise, only UVS grating movement commands to comply with a Flight Rule. UVS SWG: The E4 orbit includes several realtime UVS satellite eclipse and phase observations done at resolutions and phase angles not obtainable from the earth. The phase angle observation set includes two Io Phase observations (E4IUPHAS67 & E4IUCHEMIS), one Ganymede Phase observation (E4GUPHAS45), two Callisto Phase observations (E4CUPHAS45 & E4CUGLOBAL), and one Himalia Phase observations (E4SUHIML25). The data obtained from these phase angle observations will be used to supplement and complement the NIMS surfaceproperty measurements. In addition, Io eclipse full spectral FUV/MUV observations (E4IUIECLPS) will characterize the airglow emissions as Io enters and exits eclipse. Analysis of these data will provide the morphology of Io's atmosphere in the presence and absence of direct sunlight. UVS will also ride along with four NIMS observations of Europa. One, E4ENASTERI01 will return 4 integrated RIMs of data sampling four distinct latitudes roughly centered on 270 degrees longitude. The other ride-along observations will be with the three Surface Composition observations (E4ENSUCOMP) for which data will be recorded and 6 RIMs of data returned. These will be the first high spatial resolution observations of Europa by the UVS instrument.