ESA UNCLASSIFIED - For Official Use

esoc European Space Operations Centre Robert-Bosch-Strasse 5 D-64293 Germany T +49 (0)6151 900 F +49 (0)6151 90495 www.esa.int

Solar Orbiter Mission Planning Concept

Prepared by SOL FCT Reference SOL-ESC-TN-12000 Issue 2 Revision 0 Date of Issue 11/03/2019 Status Document Type TN Distribution

ESA UNCLASSIFIED - For Official Use

Prepared by: Flight Control Team

Approved by: ______Sylvain Lodiot (OPS-OPS) Solar Orbiter Spacecraft Operations Manager

Approved by: ______Mathias Lauer (OPS-GFS) Flight Dynamics Manager

Approved by: ______Luis Sanchez (SRE-ODS) Solar Orbiter Science Ground Segment Development Manager

Approved by: ______A. Accomazzo (OPS-OP) Solar Orbiter Ground Segment Manager

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Reason for change Issue Revision Date First Issue 1 0 2013/Sept/06 Include actions from GSDR RIDS 1 1 29-11-2013 Introduce modifications resulting from the revision of 1 2 07-03-2014 PTR ICD - see MoM SOC-MOC teleconf. 06-03-2014 Modified document as per Actions from MOC/SOC 1 3 24-02-2015 Planning Worshop #2, 14-Dec-2014 Updated document as per Actions from MOC-SOC 1 4 12-11-2015 Coordination Meeting 30-Spet-2015 Update document as per Action from MOC/SOC 1 5 13/05/2016 Coordination telecon#6. Updated document following MOC-SOC workshop in 1 6 29/05/2017 February 2017 Updated for GSRR 2 0 11/07/2019 Clarifications/changes following GSIR issue

Issue 2 Revision 0 Reason for change Date Pages Paragraph(s) Cleaned up distribution list 11/03/2019 Distribution list Pre-LTP: 11/03/2019 3.2 -pre-LTP TN is exchanged via email only - typos clean up - clarifications of pre-LTP TN content added -RSW locations to be agreed with MOC LTP 11/03/2019 3.3 - typos clean up - deletion of PTSL; not needed (PTEL is sufficient) - FECS needs PTEL MTP 12/03/2019 3.4 - deletion of PTSL; replaced by PTEL - PORMs and relative to events -> deleted - typos corrected - clarified that PTEL (and hence Fdyn commanding) remains unchanged even in case of GS deletion

STP 17/05/2019 3.5 - deletion of PTSL; replaced by PTEL - CSFs are in fact POFs - typos corrected

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VSTP 3.6 - Typos corrected LTP process to be kicked off with a pre-LTP TN psot 17/05/2019 4.3 launch Entry added for definition of planning boundaries and 17/05/2019 6 days at LTP process kick off latest Updated figure 1 with latest files (PTSL, DOR removed) 11/07/2019 Clarified RSW location 11/07/2019 3.2.2 Provision of HGAB clarified HGA steering strategy updated 11/07/2019 3.3.2 Clarification of PTR definition 11/07/2019 3.4.2 Replace PTSL with PTEL Clarification on PTR updates at VSTP level Clarification on STP file coverage 11/07/2019 3.5.2 Replaced PTSL by PTEL 11/07/2019 4.2 Nav window durations may need to be slightly extended due to new SC PMD constraints TBC Updated with more precise dates for kick off of 11/07/2019 4.3 activities Replaced DORs by FDRs 11/07/2019 3.6.1, 3.6.2

Issue 1 Revision 6 Reason for change Date Pages Paragraph(s) Full re-write, documenting current agreements 31/08/2017 all all

Old change record is kept below for reference only.

Issue 1 Revision 2 Reason for change Date Pages Paragraph(s) GSDR RID#51 25-11-2013 19 3.2 GSDR RID#20 25-11-2013 20 3.2 GSDR RDI#56 25-11-2013 39 4.4.2.2 GSDR RID #11 25-11-2013 7-9 1.3 GSRD RID#18 25-11-2013 11,12,16,25, 38 2.2.2, 2.3, 4.1.2.1 GSDR RID#19 26-11-2013 13, 16, 32-33 2.2.3, 2.3, 4.3.1.1 Conclusions from SWT#14 on commanding of RS 27-11-2013 28, 35 4.2.1.1, 4.4 instruments outside RSW and commanding of payload at VSTP GSDR RID#10 29-11-2013 30 4.3 Conclusions from the SSMM Ops Coordination 20-12-2013 32-34 4.3 workshop Revision of PTR ICD resulting in modifications to some 29-05-2014 23-30 4.1.1 to 4.2.2.1 of the processes defined in this document Update Figure 1 29-05-2014 34 4.3 Update list of TBC/TBD 29-05-2014 45 5.1 and 5.2 Managing of Power envelopes and SA steering 29-05-2014 28 4.1.5 43 4.5.2.5 Issue 1 Revision 3

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Reason for change Date Pages Paragraph(s) MOC/SOC Planning Workshop #2 Action Plan-02: 24-02-2015 22, 23 4.1, 4.1.2 Updated LTP to reflect SOC input of Comms roll strategy. MOC/SOC Planning Workshop #2 Action Plan-05: 24-02-2015 23 4.1.2 Updated LTP to reflect GS scheduling based on two booking levels by SOC. MOC/SOC Planning Workshop #2 Action Plan-03: 24-02-2015 26-30 4.2 Updated MTP to reflect use of e-FECS from SOC instead of FDYN attitude profile. MOC/SOC Planning Workshop #2 Action Plan-04: 24-02-2015 26 4.2 Updated MTP , specifying that MTP GS loop is only for releasing GS time. Removed description of Pass conduction strategy, now 24-02-2015 31 4.3 included in SOL-ESC-TN-10015 (SOL Operations Concept). Remove Comms roll strategy from list of TBDs. 24-02-2015 44 5.2

Issue 1 Revision 4 MOC/SOC Coordination AI#01: Updated STP process 12-11-2015 30 4.3 description to state that periods and deadlines stay unchanged during RSW. MOC/SOC Coordination AI#02: Expanded description 12-11-2015 34 4.4 of VSTP to include the agreement on i-VSTP commanding inputs from instruments. Issue 1 Revision 5 MOC/SOC Telecon AI#06-02: Added details on 10/05/2015 33 4.4 agreement over i-VSTP handling and submission. MOC/SOC Telecon AI#06-03: Remove reference to 10/05/2015 20, 32 3.2, 4.3.2 dedicated ranging sessions. Issue 1 Revision 6 Full re-write, documenting current agreements 31/08/2017 all all

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DISTRIBUTION LIST

Recipient Organization S. Strandmoe SCI-PSS

A. Oganessian SCI-PSS

P. Pablos SCI-PSS

A. Pacros SCI-PSS

D. Mueller SCI-S

L. Sanchez SCI-ODS

A. Accomazzo OPS-OP

SolO FCT @ [email protected] OPS-OPS

M.H. Ferreira OPS-Q

[email protected]

A. Urwin-Phipps SRE-PW

I. Tanco OPS-OPJ

E. Montagnon OPS-OPB

P. Schmitz OPS-OPE

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Table of contents:

1 INTRODUCTION ...... 8 1.1 Purpose ...... 8 1.2 Scope ...... 8 1.3 Document Structure ...... 8 1.4 Documents...... 8 1.4.1 Normative Documents ...... 8 1.4.2 Informative Documents ...... 8 1.5 Acronyms ...... 9 2 MISSION DRIVERS AND PLANNING REQUIREMENTS ...... 11 2.1 Definitions ...... 11 2.1.1 Phases ...... 11 2.2 Summary of Planning Drivers ...... 11 2.3 Planning entities ...... 12 3 PLANNING PROCESS ...... 13 3.1 Overall Process and Planning Cycles ...... 13 3.2 Pre-Long Term Planning (pre-LTP) Cycle ...... 14 3.2.1 Files used ...... 14 3.2.2 Activities, Rules, and Constraints ...... 14 3.3 Long Term Planning Cycle ...... 16 3.3.1 Files used ...... 16 3.3.2 Activities, Rules, and Constraints ...... 16 3.4 Medium Term Planning Cycle ...... 18 3.4.1 Files used ...... 18 3.4.2 Activities, Rules, and Constraints ...... 18 3.5 Short Term Planning Cycle ...... 20 3.5.1 Files used ...... 20 3.5.2 Activities, Rules, and Constraints ...... 20 3.6 Very Short Term Planning Cycle ...... 22 3.6.1 Files used ...... 22 3.6.2 Activities, Rules, and Constraints ...... 22 4 PLANNING SCHEMES ...... 25 4.1 General ...... 25 4.2 Spacecraft Navigation windows ...... 25 4.3 Commissioning and Cruise Phase ...... 25 4.4 Nominal mission phase ...... 26 4.5 Extended mission phase ...... 26 5 APPENDIX 1 MISSION PLANNING - EXPLICIT MIRD REQUIREMENTS ...... 27 6 TBCS IN THE DOCUMENT ...... 28

LIST OF FIGURES: Figure 1: file exchanges between all entities ...... 12

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1 INTRODUCTION 1.1 Purpose The purpose of this document is to define the concept in terms of processes, timelines, and rules for the mission planning activities required by the SolO mission.

The concept described in the document represents the current understanding of the planning scheme. It fully applies to the cruise phase. Further phases (years ahead) may be subject to changes and/or adaptations to be agreed by all parties.

1.2 Scope This document is applicable to the activities performed between the SolO Science Operations Segment (SOC) and the SolO Mission Operations Centre (MOC) according to the implementation agreements documented in [SOIA]. Activities taking place between the SOC and the Principal Investigators (PIs) teams are not covered by this document. This document identifies the parties involved in the planning process, the needs for these parties, and their role such that it can be used to define: • planning responsibilities • interfaces • requirements for tools • processes

1.3 Document Structure This document is structured as follows: • Section 2 gives an informal classification of mission phases depending on the planning scheme and responsibilities associated to it and identifies the planning entities relevant for the SolO mission • Section 3 defines in detail the formal steps and rules of the mission planning process • Section 4 provides an overview on how the ideal planning scheme presented in section 3 will be slightly adapted to each of the identified mission phases

1.4 Documents

1.4.1 Normative Documents [AD 1] [MIRD] Solar Orbiter Mission Implementation Requirements Document, SOL-EST-RS-02909, Issue 1.0, 16/01/2012

[AD 2] [GS SRD] Solar Orbiter Ground Segment System Requirements Document, SOL-ESC-RS-05000, Issue 1.1, 31/01/2013

[AD 3] [Deleted] [AD 4] Solar Orbiter Pointing Strategy during Remote-Sensing Windows: Science Requirements, Is.1.1, 11/12/2012

1.4.2 Informative Documents [RD 1] BC MPS URD , BC-ESC-RS-05102, Is.1.2, 30/09/2011 [RD 2] [MIP] Solar Orbiter Mission Implementation Plan, SOL-ESC-PL-00001

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[RD 3] Solar Orbiter Consolidated Report on Mission Analysis (CREMA), SOL-ESC-RP-05500 [RD 4] SolO SOC-FD ICD, SOL-ESC-IF-50005 [RD 5] [SOIA] Solar Orbiter Implementation Agreement (SOIA), SOL-ESC-IA-05002 [RD 6] Solar Orbiter Operations Rules and Constraints Document, SOL-ESC-TN-12001 [RD 7] Solar Orbiter Planning Interface Control Document (PLID), SOL-ESC-IF-05010 [RD 8] Solar Orbiter PLID Annex A: Flight Dynamics ICD, SOL-ESC-IF-50001 [RD 9] Solar Orbiter PLID Annex B: SOC/MOC ICD, SOL-ESC-IF-05012 [RD 10] Solar Orbiter PLID Annex C: ESTRACK ICD, SOL-ESC-IF-05015 [RD 11] Solar Orbiter Database Propagation Guidelines, SOL-ESC-TN-10033 [RD 12] Solar Orbiter Flight Dynamics Events file ICD, SOL-ESC-IF-50002 [RD 13] [ROLL TN] Solar Orbiter Roll Scheduling Technical Note, SOL-SGS-TN-0018

1.5 Acronyms CEB Cebreros (Ground Station) CR Command Request DDOR Delta (or Differential) Doppler One Way Ranging (also delta-DOR) DDS Data Distribution System DOR Direct Operations Request EMS ESTRACK Management System EOCR ESTRACK OSUP Change Request Portal ESTRACK ESA Tracking Network FCT Flight Control Team FDYN Flight Dynamics Team FECS Flight Events and Communication Skeleton GAM Gravity Assist Manoeuvres GS Ground Station HGA High Gain Antenna HK Housekeeping ICD Interface Control Document LEOP Launch and Early Operations Phase LGA Low Gain Antenna LTP Long Term Planning MAL Malargüe (Ground Station) MCS Mission Control System MEX MGA Medium Gain Antenna MIRD Mission Implementation Requirements Document MOC Mission Operations Centre (includes FCT, Flight Dynamics and ESTRACK) MPS Mission Planning System MTL Mission Timeline (refers to the on-board TC scheduler) MTP Medium Term Planning NNO New Norcia (Ground Station) OBC On-Board Computer OCM Orbit Correction Manoeuvre OGS Operations Ground Segment OMM OBC Mass Memory OSUP Operational Station Utilization Plan OWLT One-Way Light Time PI Principal Investigator PL Payload POR Payload Operations Request

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PTR Pointing Timeline Request PS Project Scientist or Packet Store (depending on context) QL Quick-Look RAM Random Access Memory RS Remote Sensing RSW Remote Sensing Window SA Solar Arrays or Service Agreement (depending on context) SAP Science Activity Plan S/C Spacecraft SES Sun-Earth-Spacecraft angle SGM Safeguard Memory SGS Science Ground Segment SOC Science Operations Centre SOIA Science Operations Implementation Agreement SOM Spacecraft Operations Manager SOR Standing Order Requests SSID Sub-Schedule ID SSMM Solid State Mass Memory STP Short Term Planning TBC To Be Confirmed TBD To be Defined TC Telecommand TFG Transfer Frame Generator TM Telemetry TT Time-Tagged TT&C Telemetry, Tracking and Command TX Transmitter VEX VSTP Very Short Term Planning WOL Wheel Off-Loading

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2 MISSION DRIVERS AND PLANNING REQUIREMENTS

This chapter analyses the mission from the point of view of the items that are relevant to the planning concept. At the end a summary of all drivers is presented and a traceability to their implementation in processes and tools is offered.

2.1 Definitions

2.1.1 Phases

From a planning point of view, and in accordance with the definitions in [MIP] the following phases can be identified with respect to planning needs and schemes:

LEOP (outside the scope of this document) Commissioning Cruise Nominal Phase Extended mission Phase

2.2 Summary of Planning Drivers The Mission Planning drivers and requirements can be found in the MIRD [AD 1] and GS SRD [AD 2].

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2.3 Planning entities The following entities are to be considered as part of the planning process of the SolO mission:

• PI teams (PI) and project scientist (PS) • SolO Science Operations Center (SOC) • SolO Science Ground Segment (SGS) comprising PIs and SOC • SolO Mission operations Center (MOC) • Flight Dynamics Team (FDyn) at MOC • Flight Control Team (FCT) at MOC

The following mission external entity is interfacing the SolO mission at planning level: • ESTRACK Scheduling Office (SCHEDOD)

This interface is not directly exposed to SOC and is managed by the FCT. The next figure shows a high level view of the exchanges occurring in the mission planning process. The figures below show all file exchanges between planning entities (ie inputs and outputs).

Science Ground Segment

Pre LTP TN PTR PTRV

FDS

PLNVIEW

ESTRACK

OSSUPDs EVFM

FCT/MPS

Manifest files Pass sheets SORA

MCS/Automation

Figure 1: file exchanges between all entities

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3 PLANNING PROCESS

3.1 Overall Process and Planning Cycles

In general the mission planning process is characterised by an incremental development of detail based on a progressive availability of information: • definition of the boundaries, availabilities, and constraints within which the operations have to be planned • definition of the operations to be executed: typically attitude and commands requests for the spacecraft • validation of the operation requests: typically consistency and feasibility of the requests is checked; • detailed scheduling of the operations requests with generation of the final products (commands) used to conduct the operations

In the case of SolO the following planning cycles are identified to conduct the activities defined above: • A pre-long term planning cycle (pre-LTP) whose objective is to get all relevant information to start the LTP process, and in particular a ground station schedule • A long term planning (LTP) cycle whose objective is to establish the framework of operations on which SOC can plan the detailed science operations for the upcoming orbit. This framework includes orbital events, platform operations and estimates of resource profiles (e.g. power and data rate available) • A medium term planning (MTP) cycle where the objective is to define and validate a baseline set of instrument operations for the relevant period. The validation is performed against a set of planning rules previously agreed upon by all parties • A short term planning (STP) cycle where the objective is to generate the set of platform and instrument commands to be uplinked to the spacecraft to cover the upcoming 7-days planning window • A very short term planning (VSTP) cycle during RSW and their precursor windows only where the objective is restricted to the refinement of spacecraft guidance and some instrument commanding on very short timescales. And in particular, only during those RSWs in which the SAP specifies as a scientific objective the identification and tracking of surface features and connectivity goals

This documents defines the baseline for the planning cycles. Deviations (typically in lead and turn-around times) are possible and will be agreed on ad-hoc basis between MOC and SOC.

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3.2 Pre-Long Term Planning (pre-LTP) Cycle

3.2.1 Files used • ESTRACK service agreement (ULP) • ESTRACK Ground station schedule (PLANVIEW) • Pre-LTP technical note from SOC • HGA blockage periods (HGAB) • Long term events (EventsLT)

3.2.2 Activities, Rules, and Constraints

Fdyn produces/updates the EventsLT file which contains GS visibility information required to define the Solo ESTRACK plan. ESTRACK typically plans the long term allocation of stations 7/8 months ahead of a 6 months period. Some pre-LTP work is required by both MOC and SOC to prepare for the ESTRACK ground station negotiation meeting where the station allocation per mission is finalised. • RSW locations are pre-defined by SOC for the whole mission once a launch date is available. These locations are fine-tuned by SOC at pre-LTP level. The locations shall be selected after iteration and agreement between SOC and MOC to avoid conflicts with operational constraints (navigation windows have full priority, see 4.2). • SOC may provide station planning rules updates (compared to the available ULP) applicable for a specific time period. Such rules allow the SOC to optimise data return by maximizing science data downlink • The choice of the standard roll angle for the upcoming LTP period (see SGS-FD ICD) shall be provided by SOC

All this information is required by MOC four weeks before the ground station negotiation meeting and is provided (via email only) in a pre-LTP technical note from SOC. For this, SOC requires the HGA blockage periods (4 weeks before). On request full mission HGABs are possible. The HGAB produced by Fdyn provides allowed roll angles to be used on a given day and what are the blockages relative to the default pointing. RSWs may somewhat impact the ground station schedule. The baseline agreement comprises 30 days of RSW per orbit in a three ten day split. Deviations from this shall be agreed with MOC. A split at perihelion for MAG (5 day RSW, 3 day fully EMC quiet, 5 day RSW) is for example acceptable. The split has nevertheless the disadvantage of not having a precursor window for the second 5 day RSW window. The number of precursor days (4 before each 10 day slot, 12 in total) and number of VSTP days (30) shall in any case not increase. Precursor windows are fixed and start 4 days before the RSW start (for processing time and data dump time).

• Special tracking needs for navigation (for GAMs) are identified by Fdyn and passed on to the FCT for booking of resources

Therefore at pre-LTP: • Fdyn produces/updates the EventsLT and HGAB files as input to SOC for the pre-LTP TN • MOC informs SOC when the negotiation meeting will take place typically 6 weeks before the meeting. • SOC provides fine-tuned RSW locations via a so called pre-LTP technical note (per email only) typically 4 weeks before the negotiation meeting.

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• Fdyn provides tracking needs for GAMs typically 4 weeks before the negotiation meeting. • FCT processes these inputs which are then ideally reflected in a draft station allocation plan available before the negotiation meeting. MOC iterates with SOC and Fdyn as required/needed in order to be ready to negotiate relevant required changes.

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3.3 Long Term Planning Cycle

3.3.1 Files used • Pre-LTP technical note from SOC • ESTRACK Ground station schedule (PLANVIEW) • User Event File (UEVT) • Flight Event and Communications Skeleton (FECS) • Long term Orbit file (OrbitLT) • Planning timeline events (PTEL) • Long term event file (EventsLT)

3.3.2 Activities, Rules, and Constraints

LTP covers the ground station negotiated coverage, truncated slightly where necessary to contain an exact number of STPs (ie weeks) and complete RSWs (ie RSWs shall not be split). The first step of the LTP is for MOC and SOC to agree on the LTP as well as MTP and STP boundaries (including VSTP boundaries and synchronisation points). These boundaries shall be at a fixed time as far as possible, and considering ground station coverage (for TC uplink opportunities). STP and VSTP boundaries (synchronisation points) are reflected in the PTEL. Synchronisation points are defined by MOC and highly depend on the ground station coverage. LTP boundaries are defined in the FECS. The Pre LTP SOC TN provided at pre-LTP also contains simple roll rules to be applied for this specific LTP. These simple rules cover all types of rolls (communication/calibration/science) and are defined in [ROLL TN]. The pre LTP TN also provides guidelines on where to place calibration windows (roll + flat field, anything needed in PTEL) and contains the corresponding calibration roll requests for the given LTP (limited to 1 or 2 predefined calibration activities outside precursor and RSW windows per orbit, and 1 or 2 in the precursor slots). Roll for camera calibrations occur in the RSW precursor windows.

With this input Fdyn prepares a PTEL file to be processed by the FCT and SOC. This file contains: • Slots for mechanism movements (Solar Arrays, HGA) and their steering strategies during passes • Wheel off-loading slots • Spacecraft navigation slots • OCM slots • Rolls • Calibration slots • Sync blocks during RSWs (update opportunities at VSTP level)

At perihelion, a WOL every 3 days TBC is required. Frequency may be lower at higher Sun distances. OCM slots in addition to the navigation slots around the GAMs are needed for navigation. Typically one slot per month is expected. All roll slews are performed with +X SC axis pointing to the centre of the Sun disk. This means first a slew to point +X SC to the Sun centre takes place followed by a roll slew. When Fdyn defines roll angles at LTP, enough margin is accounted for, and among other things, up to 1 degree departures of +X SC axis from the direction to the Sun centre during RSWs. Final roll angle (and a sufficient window within which the change occurs) is made available to SOC (via the PTEL). But the full roll profile is not required. HGA slots guarantee ground contact during station passes and minimize disturbances to payloads (in particular inside RSW windows). The HGA is steered frequently enough during a ground contact such that the Earth does not leave a 3dB cone around the HGA boresight. SA slots adjust the SA angle required at any given Sun distance and minimize disturbance to payloads (in particular inside RSW windows).

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Fdyn also updates the OrbitLT and EventsLT files.

With the UEVT, the EventsLT, the PTEL, and the PLANVIEW, MOC generates a FECS for SOC. The FECS includes the following information: • TM bit rates • Ground station schedule including dump periods

With the available TM bit rate, the real time TM generation rate and the OMM data storage rate (numbers to be provided in [RD 6]), SOC is in a position to calculate the bandwidth available for science downlink and compute the SSMM fill status. No SSMM data volume checks are done on the MOC end, in any of the planning cycles.

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3.4 Medium Term Planning Cycle

3.4.1 Files used • MTP Pointing timeline request (PTR) • MTP Payload operations requests (MTP POR) • Ground station pass cancellation or truncation (OSSUPDs) • ESTRACK Ground station schedule (PLANVIEW) • User Event File (UEVT) • Flight Event and Communications Skeleton (FECS) • Orbit file (OrbitLT) • Long term event file (EventsLT) • Planning timeline events (PTEL)

3.4.2 Activities, Rules, and Constraints

MTP covers the LTP period agreed in the LTP process. SOC submits a PTR to FDYN 4 weeks before the start of the MTP (TBC, the delivery may occur closer to the start of the precursor window). The PTR defines the pointing for the full RSW period, including the precursor days. Several pointing types including standard Sun centre pointing or special pointings for calibrations can be requested following the rules in [RD-4]. The PTR defines only departures from the LTP attitude baseline. This includes calibration (from precursor) as well as RSW windows. The PTR covers the full RSW window including the precursor days. It shall be consistent with the information contained in the PTEL. The PTR is cross checked by Fdyn. Target is to have a valid PTR latest two weeks before the start of the precursor window. The number of iterations required shall be limited.

Subsequent RSW related inputs are submitted at VSTP. The SOC knows which specific VSTP slots are to be used for PTR updates (ie delta-PTR deliveries for example to track features). This information is passed on to MOC in the delivered PTR. For this, a SYNCH block shall be inserted into the PTR only for the PTEL VSTP_UPDATE slots for which delta-PTR deliveries are foreseen.

SOC uses the pointing catalogue defined by Flight Dynamics in [RD 4] to build the PTR. SOC defines the baseline of instrument activities for the entire planning period, and submits them to the FCT as PORMs (MTP Payload Operations Requests). These contain a fixed timeline of operations, with direct reference to FOP sequences to be executed at fixed times. These are typically used for time-specific observations. SOC submits PORMs to MOC 4 weeks before the start of the MTP. Operation of RS instruments out of RSW may be accepted, but are subject to the following constraints: • The operations are planned in the same way as nominal operations, i.e. routine inputs due as part of MTP (no last-minute operations are allowed). • All the TM produced during Out-of-RSW ops is accounted for as part of the instrument total TM allocation. • The operation must satisfy the normal interference rules (must be OK with IS instruments).

MTP PORs may be refined by SOC between MTP and STP (when becoming STP PORs), with the constraint that the level of resource usage (Power, data generated) established by the baseline plan may not be exceeded on the STP revision i.e. any changes to the instrument activity baseline must be resource-neutral.

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FCT aggregates the different inputs (Payload Operations requests, EventsLT and PTEL from Flight Dynamics, PLNVIEW and UEVT), and propagates a plan for the complete MTP, modelling the usage of on-board resources (power/OMM data storage bandwidth) and validating it against all system level constraints. The result will be available latest 2 weeks before the start of the concerned MTP.

SOC may also submit requests to remove or shorten passes. SOC will notify MOC via email (Solo planning account). MOC will then generate the relevant OSSUPDs. Passes can only be shortened or cancelled. This can be decoupled from the MTP process. Cancellation/truncation of passes needs to be known one month latest before the affected pass. Ideally all changes are to be provided by SOC in one or two goes. The PTEL nevertheless remains unchanged. This means that HGA slots for ground contact remain unchanged).

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3.5 Short Term Planning Cycle

3.5.1 Files used • Payload operation requests (POR) • MTP Pointing timeline request (PTR) • Frozen ESTRACK stations allocation (PLANVIEW) • Attitude File (Attitude) • Updated STP Event File (Events) • Sun Aspect Angle File (SAAF) • Flight Dynamics Requests (FDR_) • STP Orbit file (Orbit) • Planning timeline events (PTEL) • One Way Light Time File (OWLT) • Planning Operations Files for the spacecraft (POFs); TC files and TC file execution schedules • Schedule for the automation system (SORA) • ESTRACK Ground stations schedule (EVFM) • Pass Sheets • Manifest file;

3.5.2 Activities, Rules, and Constraints The process is triggered with the submission of the final set of PORs by SOC 5 days before the first activity is executed, and its duration covers the upcoming week, based on boundaries defined in the FECS.

During RSW periods, STP cycles run unchanged with respect to non-RSW periods. All input deadlines and durations remain the same as during routine operations, although planning activities are done with special care to avoid planning problems associated to discontinuities at boundary conditions. The figure below provides an example overview of the STP process. Exact planning days and boundaries will be finalised at a later stage, latest when triggering the first LTP cycle.

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The PORs include daily requests for the S13 downlink queue management.

Based on the PTEL and/or PTR FDyn generates the final operational products: • Attitude File (Attitude) • Updated STP Event File (Events) • Sun Aspect Angle File (SAAF) • Flight Dynamics Requests (FDR_) • STP Orbit file (Orbit)

With the exception of Orbit and Events all the FDn products just cover the STP time period. FDRs overlap into the previous STP. The Events file starts @ tlaunch and covers at least till the end of the concerned LTP. It is updated with newer information at each STP. The attitude events (ie all attitude dependant events) only cover until the next STP cycle for with the commands were generated.

From the short term PORs submitted by SOC, the Fdyn products (Events, SAAF, FDR_, PTEL) and the PLNVIEW, FCT generates the TC files and file execution schedules for platform and payload activities (via a manifest file). An uplink strategy, including management of the MTL, is defined and an automated schedule is generated to control the uplink via the MCS. Station and automation timelines are also generated.

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3.6 Very Short Term Planning Cycle

3.6.1 Files used • Instrument VSTP (iVSTP)Direct Operation Requests (VSTP RSW PDORs -> VDORs) • VSTP Pointing requests (PTRV) • Fdyn Direct Operation Requests (FDRs)

3.6.2 Activities, Rules, and Constraints

Although the attitude guidance during RSW is determined and refined as part of the VSTP cycle, the initial attitude immediately at the start of the RSW can only be determined in the precursor observation. This set of observations is performed using the baseline guidance as defined during the current MTP cycle, and the resulting data is then processed in a dedicated VSTP cycle with the sole objective of refining the attitude guidance for the upcoming RSW. The figure below provides an overview of the activities during the precursor observations.

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RSW Days

-3 -2 -1 0 1 2 Precursor Guidance Onboard (from MTP) GS #1 GS #2 GS #3 Guidance Set

Ground Pass MAL MAL MAL MAL MAL

Ground Events QL data down SGS Process QL, Gen Activities dPTR FDYN New Activities FDRs OGS New Activities TCs

Instrument commanding at VSTP (so called i-VSTP) is allowed for a limited set of instrument commands. These requests are white-listed by the SOC (in an agreed with MOC list, MOC also white lists these requests) prior to submission to the MOC. MOC uplinks any PDOR requests received up to 24 hours prior to the start of the next Ground station pass on the agreement that :

• the requests are only restricted to Remote Sensing Windows • there is no deletion of previously loaded commands involved • there is no modification to MTP/STP-checked resource envelopes (i.e. parameter changes are OK, unit mode changes are notOK). • it is accepted that this is a non-critical, single-shot operation (i.e. OK if missed, no backup). • it is non-revocable. • it is only possible if it has been previously discussed and agreed with SOC & MOC.

For planning of iVSTP activities, SOC delivers a PDOR to MOC. The PDOR ground file name must match the one defined at STP. The VSTP itself is triggered at the start of the precursor observation and runs through to the end of the RSW. It is composed of three repetitive main cycles, each lasting 24 hours, under the responsibility of SOC, FDYN and FCT respectively. The figure below provides an overview of the VSTP process.

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Note that, due to the tight time requirements during this process, there is no possibility to iterate the inputs in case of a request failing to pass any constraint checks. Thus, in case of failed PTR checks, the guidance update will not be executed and the previously loaded one will be followed. The same applies to VDORs. The figure below shows possible updates every third day for space reasons. Daily updates are allowed. RSW Days

-1 0 1 2 3 4 5 6 7 8 9 Onboard GS #1 GS #2 GS #3 GS #4 GS #5 GS #6 GS #7 GS #8 GS #9 GS #10 Guidance Set GS #4 GS #5 GS #6 GS #7 GS #8 GS #9 GS #10 GS #7 GS #8 GS #9 GS #10

Ground Pass MAL MAL MAL MAL MAL MAL MAL MAL MAL MAL

Onboard activities Ground Updated Guid. QL data down Events Sets #4 onwards Updated Guid. Set #7 onwards SGS Process Process Activities QL, Gen QL, Gen dPTR dPTR FDYN New New Activities FDRs FDRs

OGS New New Activities TCs TCs

During RSW, quick-look (QL) data covering the previous 24 hours is downlinked daily with high priority. SOC retrieves this QL data automatically and uses it to assess the quality of the tracking guidance as executed up to that point. If necessary, a refinement to the latest guidance request can be resubmitted, and daily submissions are allowed for the duration of the RSW. TBC the (PTRVs or synchronisation points) cover the period starting at the end of the pass 72 hours in the future (the first affected VSTP), until the end of the RSW. The SOC has TBC 24 hours (counting from the start of the current pass until the start of the next) to perform the analysis and provide the updated pointing timeline. Flight Dynamics takes the latest submitted PTRV and re-validates the resulting guidance profile for the remainder of the RSW. Particular care is taken to ensure the continuity of the guidance segments at the boundary between the previously loaded baseline and the future guidance segments. As an output, Fdyn produces a new daily set of Flight Dynamics Requests (for the relevant VSTPs) detailing the refined guidance profile. TBC FDYN is allocated 24 hours to perform this activity.

RSWs involve daily support, including weekends, for the duration of the RSW. The procedure to update the guidance TBC includes the following: 1. Upload a new GS chain of Delayed TC files 2. Verify Reception of all GS at the S/C 3. Update pointer to first GS in the new chain.

FCT uplinks the corresponding VDORs and the FDRs. No MPS activities are planned.

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4 PLANNING SCHEMES

4.1 General For non-blockage periods MOC intends to fly the default in-orbit plane. Other options are Sun equatorial/ecliptic. MOC may deviate from the chosen attitude if required for operational reasons (ex comms windows/OCMs) and only in such windows. It is OK to change the default attitude during the mission (for example have different attitudes during cruise/nominal mission/extended mission) but MOC needs to know what is needed before launch.

State models of all instruments are defined by MOC at sequence level. Identification of states via sequence parameters shall be avoided.

4.2 Spacecraft Navigation windows During navigation windows (-4 weeks to +1 week around a GAM) navigation has priority and full flexibility is required.

In particular Fdyn may want to deviate from the default industry-defined SA movements which are only determined by Sun distance. It is preferable to have a fixed SA position during the navigation windows.

GAMs are identified in the FECS by full 5 week long navigation windows. These windows may need to be slightly extended due to the SC PMD constraints. Actual navigation slots will be provided to SOC latest 4 weeks before the start of the navigation window. These may be activity blocks (ex 12h long) which cover all needs for WOLs/OCMs.

Once the windows are defined, an updated PTEL could be redelivered to SOC.

Knowledge of SA position and HGA movements during GAM arcs only comes later. This information will not be provided to SOC. This information can be retrieved from TM.

4.3 Commissioning and Cruise Phase

During the cruise phase, the only deviations from the standard planning process are:

• It is proposed to start the first LTP planning cycle right after commissioning completion. Default attitude would be flown during the bridging period. Simple roll rules can be applied. Start of LTP is TBD (but could be end of commissioning). The first pre-LTP TN will be provided by SOC post launch and the process kicked off from there. In particular: o HGAB and EventsLT files to be provided to SOC within one week after launch o SOC to then provide a pre LTP TN. Target should be one week after o Fdyn to respond with a PTEL around 2 weeks after that • STP durations may be increased to up to 3 weeks ie STPs may be merged • There are no VSTPs. • There is no PTR IF for payload checkouts. The first usage of the PTR IF is the final instrument checkout (with a PTR IF test one year before that). • MOC does not support science activities during cruise (outside agreed checkout windows and/or special calibrations/pointings)

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4.4 Nominal mission phase Rules defined in section 3 fully apply. These may need adaptation once in flight. Changes will be agreed with all parties. In particular a simplification of the MTP phase can be foreseen (for example limiting it to PTR delivery and GS changes only).

4.5 Extended mission phase

Calibration roll requirement requests may be increased to potentially 3-5 per LTP in the EMP when the orbit period becomes shorter.

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5 APPENDIX 1 MISSION PLANNING - EXPLICIT MIRD REQUIREMENTS

The following requirements have been apportioned to Mission Planning in the MIRD [AD 1]:

MIRD-90 The MOC shall plan the Science Operations according to the inputs submitted by the SOC, following a cyclic process: • Long-term planning will define the baseline payload operations plan (including baseline attitude) based on the scientific objectives around 6 to 12 months in advance of the actual operations. • Medium-term planning will translate the baseline plan into a first set of PL command requests (by SOC) to allocate resources and identify possible conflicts on instruments operations. • Short-term planning will freeze resources and produce the sequences of commands to be uplinked to the spacecraft. Deadlines for submission of requests in this phase will be in the order of one week before the event.

MIRD-91 The MOC shall allocate the resources required to fulfil the mission plan taking into account the demands of other users. Unresolved conflicts shall be handled within the mission planning process for resolution through re-planning.

MIRD-92 In contingency cases it shall be possible to modify an existing instruments operation after expiration of the normal deadline up to 3 working days before execution.

MIRD-93 As part of the planning cycles, the MOC shall provide SOC with payload operations exclusion windows, on-board resources envelopes for payload operations and the ground station schedule corresponding to the planned operational periods.

MIRD-110 The MOC shall be able to accept from the SOC the inputs (e.g. mission planning inputs, command requests) necessary for the scheduling of payload operations.

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6 TBCS IN THE DOCUMENT

Section Description Due date for resolution 3.3.2 VSTP boundaries in FECS TBC In cruise 3.5.2 Exact planning days and boundaries will be finalised at Latest when defining first LTP, for cruise; a later stage, latest when triggering the first LTP cycle. Nom phase can be decided later

3.6.2 (a) PTRV coverage period In cruise (b) Turnaround times are TBC (c) Exact FCT procedure for ULing a new guidance set 3.4.2 PTR delivery 4 weeks before MTP start; could be 4 In cruise (TBC) weeks before start of precursor window 3.4.2 Used VSTPs input to MOC is TBD In cruise 4.2 Refinement of nav slots and updated PTEL In cruise

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