31May2017

SPWGTelecon

ThisisasubsetofslidesfromtheSPWGtelecon toshowthe

discussionofAttitudeAdjustmentplanning

53-dayorbithigh-levelRe-planTheNewMission– recapfromJSTmeeting• PJ7 – PJ10:

– Thenextuplinkdrivenmilestoneisamid-September(orearlier)decisiononwhetherPJ9isMWRtilt(currentbaseline)vs MWRnadir;nochangestoPJ7-PJ8,whichareMWR-nadir,GRAV,resp.; Decision:PJ9willstayMWRtilt, PJ10needstobeanalyzedGRAVvs MWR(see“AttitudeAnalysis”slide)

– GRSoverflight tradeswillneedtobefinalizedinAugust(afterPJ7)• GravityishappywithgettingPJ21• Noneedtochangecurrentplanbyswappingaroundlongitudes• ButfinaldecisionwillbemadeafterPJ7

• MWRxtrk orientationwillbemovedtoPJ18(fromPJ12)– NoimpacttoMWRscience– PJ18wasviablepossibilityanywaywrt Gravityscience– AllowsbetteruseofJADE,JEDI,UVS,JIRAMandJunoCam inPJ12while

geometryinnominalattitudeisstillOK(butwhichgeometry– gravityorMWR?) Leaveasopenitemfornow– personnelconcerns 2

3

JunoOrbitGeometry

Updatedchartsshowninmeetingwillbeemailedoutseparately

53-dayorbithigh-levelRe-planTheNewMission– recapfromJSTmeeting• BeyondPJ12needtoturnawayfromgravityorientationtorestore

JADE,JEDI,UVS,JIRAMandJunoCam viewinggeometry– Needcommonterminologytodescribeoffsetangles – done,seeprevious

slides– Missionplanningteamwillsupplyc kernelsforGRAV,MWR,MWRtilt,MWR

cross-track,plus30-degand60-degoff-Sunforspecificorbits• Gravityteamfeedback:

– WanttokeepPJ21(GRS)andPJ23(occultation)– WillingtogiveupPJ24andPJ32rightnow– Otherpj’s alsoapossibilitybutdon’twanttoloseseveralinarow

• Adhocworkinggroupcameupwithfirstcut(nextpage)• Powerwillbeanimportantconstraint– projectisworkingonanewtoolto

estimatepowerasafunctionofangleoff-sun – willseefirstresultsinJune21SPWGtelecon

• MWRwouldlikeconsiderationofanotherdegreeoffreedomtotiltnorthwardafterorbit18duetoorbitrotationsouthward– isthispossible? 4

AttitudeAnalysis

5

• JIRAMidentifiedPJs witha(*)todenotethattheyhaveahigherpreferencetonotdoMWRorientationbecauseoftheexpectedradiationagingeffectsontheirradiatorpaint(i.e.,thermalissues)• HighlightedrowsrepresentthepreliminarylistofPJs tosupporta“MWR-like”tiltfortheparticleinstruments.ThiswasdiscussedwithUVS,JIRAM,JADEandJEDI.• MartyandStuartwillproduceC-Kernelsforthetypicaltilts(grav,mwr,xtrack,etc.)plus30and60degreeoffSuncasesforevaluationofthesespecificorbits• Engineeringdataisstillneeded(e.g.,durationoftilt,instrumentkeepoutdurations,whencanwestartthere-orientation,etc.).

NewPJDatesDatesfor53dayorbits,near-term

– PJ-02:Oct19,2016– PJ-03:Dec11,2016– PJ-04:Feb2,2017– PJ-05:Mar27,2017– PJ-06:May19,2017– PJ-07:July11,2017– PJ-08:Sept1,2017– PJ-09:Oct24,2017(conjunctiononOct26,2017)– PJ-10:December16

Jet Propulsion LaboratoryCalifornia Institute of Technology

75/23/2017Stuart Stephens Juno Project

Juno Science Team Meeting (SwRI, San Antonio) – Mission Planning StatusThis document has been reviewed and determined not to contain export-controlled technical data

This document was reviewed and approved for export, see Juno-17-007

Trajectory plots [1/2]View from North pole

Blue = Orbits 1 & 3-5 (yields initial 90-deg spacing)Brown = Orbits 6-9 (45-deg spacing)Green = Orbits 10-17 (22.5-deg spacing)Magenta = Orbits 18-33 (11.25-deg spacingPurple = Orbits 34-35 (extra and deorbit)

Jupiter North Pole view,Sun direction fixed (down)

170320 reference trajectory

Jet Propulsion LaboratoryCalifornia Institute of Technology

85/23/2017Stuart Stephens Juno Project

Juno Science Team Meeting (SwRI, San Antonio) – Mission Planning StatusThis document has been reviewed and determined not to contain export-controlled technical data

This document was reviewed and approved for export, see Juno-17-007

Trajectory plots [2/2]View from Sun

Blue = Orbits 1 & 3-5 (yields initial 90-deg spacing)Brown = Orbits 6-9 (45-deg spacing)Green = Orbits 10-17 (22.5-deg spacing)Magenta = Orbits 18-33 (11.25-deg spacingPurple = Orbits 34-35 (extra and deorbit) View from Sun

170320 reference trajectory

Jet Propulsion LaboratoryCalifornia Institute of Technology

92/6/2017Stuart Stephens Juno Project

Juno Science Team Meeting (SwRI, San Antonio) – Mission Planning StatusThis document has been reviewed and determined not to contain export-controlled technical data

This document was reviewed and approved for export, see Juno-17-003

• GRAV and MWR PJ attitudes are shown below, along with MWR tilt attitude:– The MWR tilt attitude

would bring the head of the +Z S/C spin axis vector, the one pointing toward the HGA [*], up and out of the paper (negative 14º rotationabout Jupiter-to-Juno vector, using the right-hand rule).

– The MWR cross-track attitude would orient the +Z S/C spin axis parallel to the Jupiter N pole vector (with ~90-deg turns before/after, and putting solar arrays off-Sun, similar to main engine burn attitude).

[*]

Jupiter-to-Junovector

–14º rotation about the ...

(–14º isclockwiseif we lookdown onthe pointyend of the

arrow)

Perijove attitudes: GRAV,MWR, MWR tilt, and MWR cross-track

MWR tilt:

MWR cross-track: