solar probe plus a nasa mission to touch the sun solar probe plus science workshop march 26, 2013...

Solar Probe PlusA NASA Mission to Touch the Sun

Solar Probe Plus Science Workshop March 26, 2013


Nicky FoxSPP Project Scientist

[email protected]

Solar Probe Plus - Solar Orbiter Collaboration Discussion

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Solar Orbiter Science Operations Working Group November 6, 2013

Science Questions Addressed by Solar Probe Plus

Overarching Science Objective To determine the structure and dynamics of the Sun’s coronal

magnetic field, understand how the solar corona and wind are heated and accelerated, and determine what mechanisms accelerate and transport energetic particles.

Detailed Science Objectives Trace the flow of energy that heats and accelerates the solar corona

and solar wind. Determine the structure and dynamics of the plasma and magnetic

fields at the sources of the solar wind. Explore mechanisms that accelerate and transport energetic particles.

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Level 1 Objectives & Processesrequire high quality, integrated measurements

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L1 Science Objectives

Sample Processes

Needed Measurements

Instruments

1. Trace the flow of energy that heats and accelerates the solar corona and solar wind.

2. Determine the structure and dynamics of the plasma and magnetic fields at the sources of the solar wind.

3. Explore mechanisms that accelerate and transport energetic particles.

- heating mechanisms of the corona and the solar wind;

- environmental control of plasma and fields;

- connection of the solar corona to the inner heliosphere.

- particle energization and transport across the corona

- electric & magnetic fields and waves, Poynting flux, absolute plasma density & electron temperature, spacecraft floating potential & density fluctuations, & radio emissions

- energetic electrons, protons and heavy ions

- velocity, density, and temperature of solar wind e-, H+, He++

- solar wind structures and shocks

FIELDS-Magnetic Field-Electric Field-Electric/Mag Wave

ISIS-Energetic electrons-Energetic protons and heavy ions-(10s of keV to ~100 MeV)

SWEAP-Plasma e-, H+, He++-SW velocity & temperature

WISPR- White light measurements of solar wind structures



Reference Mission: Launch and Mission Design Overview

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Launch Dates: Jul 31 – Aug 19, 2018

(20 days) Max. Launch C3: 154 km2/s2 Requires Atlas V 551 class

with Upper StageTrajectory Design

7 Venus gravity assist flybysFinal Solar Orbits

Perihelion: 9.86 RS

Aphelion: 0.73 AU Inclination: 3.4 deg from

ecliptic Orbit period: 88 days

Mission duration: 7 years

Sun

Venus

Mercury

Earth

Launch7/31/2018

1st Min Perihelionat 9.86 RS

12/19/2024

1st Perihelionat 35.7 RS

11/1/2018



Reference Vehicle: Anti-Ram Facing View

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Reference Vehicle: Ram Facing View

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Reference Vehicle:Concept of Operations

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SPP Rapidly Explores the Inner Heliosphere

8

0

5

10

15

20

0 300 600 900 1200 1500 1800 2100 2400 2700

Time (days from launch)

Peri

heli

on

(R

s)

0

0.2

0.4

0.6

0.8

1

1.2

0 300 600 900 1200 1500 1800 2100 2400 2700

Time (days from launch)

So

lar

Dis

tan

ce (

AU

)

+ 1st perihelion (0.16 AU) 3 months after launch

+ 24 passes below 43 Rs

+ 19 passes below 20 Rs



Mission Trajectory

Venus Flyby #7Nov 2, 2024

Mercury

Venus

Earth

Sun

First Perihelionat 35.7 RS

Nov 1, 2018

First Min Perihelionat 9.86 RS

Dec 19, 2024Venus Flyby #1Sept 28, 2018

Venus Flyby #2Dec 22, 2019

Venus Flyby #3Jul 6, 2020

Venus Flyby #4Feb 16, 2021

Venus Flyby #5Oct 11, 2021

Venus Flyby #6Aug 16, 2023

LaunchJuly 31, 2018

99



Solar Probe: Science Payload FIELDS:

PI: Stuart Bale, UC Berkeley SSL E-Field Antennas Magnetometers (MAGi, MAGo & SCM)

SWEAP (Solar Winds Electrons Alphas and Protons): PI: Justin Kasper, Smithsonian CFA SPC (Solar Probe Cup) SPAN (A & B)

ISIS (Integrated Science Investigation of the Sun) PI: Dave McComas, SWRI EPI-Hi EPI-Lo

WISPR (Wide-field Imager for Solar Probe) PI, Russell Howard, NRL

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WISPR

EPI-Lo

EPI-HiSPAN-A

MAGFGM

MAGSCM

E-Field Antennas

SPCE-Field Antennas

SPAN-B


Solar Orbiter Science Operations Working Group

Payload Nominal Operations – A day in a life of an instrument

During the solar encounter period (inside 0.25 AU) all instruments will be powered on, continuously collecting science data Responding to s/c time & status message, containing MET at the next virtual PPS,

instrument & s/c data shared with all of the instruments, instrument SSR allocation used status

Flags include solar distance, thruster fire, instrument power down warning, processor transition, start up modes (safe or full science), data rate indicator, etc.

Executing the uploaded command sequences autonomously (no time-tagged commands are coming in from the spacecraft)

Recording data in their own memory or sending it over to s/c SSR via UART or SpW Once instrument has exceeded their orbit allocation, the data is no longer

recorded on the s/c SSR Outside of the solar encounter period (outside 0.25 AU), the instruments could be

powered on when the spacecraft is not in power or operationally constrained mode E.g. TCMs, Ka-downlink, spacecraft health checkouts, copying data from instrument

DPUs to the spacecraft SSR (bulk memory), or other CPU utilization constraints, operation at solar distance >0.82AU following the first perihelion during thermal slews (thermal constraint).

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Solar Orbiter Science Operations Working Group

SPP-SO Orbit Trajectory Movie

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Questions for Solar Orbiter

At what phases of the mission will you have various data products and at what time resolution?

Is synoptic data good enough for close collaboration with SPP or do we need burst data?

How do we coordinate burst data? Is there capability to reassign telemetry?

E.g. can the in-situ instruments take more data during the early phase of the mission when the remote-sensing instruments are powered off?

What is the lead time for commanding? What is the cadence of the SolOHI images. Will there be regular

synoptic images of the location of SPP? Especially when SPP is behind the Sun.

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Solar Probe PlusA NASA Mission to Touch the SunA NASA Mission to Touch the Sun

Orbit Planning ProcessOverview

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Solar Orbiter Science Operations Working Group November 6, 2013 15

0.25 A.U.

0.25 A.U.

Cruise/Downlink Period

24 Solar Encounter Orbits

Orbital Periods Vary (168 days to 88 days)

Encounter Operations Primary science data collection phase – All

instruments will be powered on Fanbeam antenna periodically available for

communications & Nav No SSR Playbacks

Orbital Operations Concept

(10-11 Days)

Cruise Operations Instruments Can Be Powered On (Sun Distance <

0.82 AU) Instruments off during some activities Fanbeam for communications – H/K data only

Commanding as needed to support spacecraft maintenance

Science Downlink Operations All instruments powered off HGA for communications – SSR playbacks Commanding as needed to support spacecraft

maintenance

Solar Encounter Period

Cruise/Downlink Period

Solar Encounter

Period



Orbit Planning Activities Detailed operations planning performed for each orbit

24 total orbits (Orbital period varies between 168 - 88 days)

Key operations planning required for each orbit include: Venus Flyby Events TCMs Spacecraft Slews HGA downlink opportunities

High priority downlink periods each orbit Dictates SSR management scheme Slews will be required for some downlinks

Spacecraft housekeeping & maintenance activities Flight software loads Command Sequence Uplinks Autonomy loads Parameter maintenance Special sub-system and/or payload tests

Eclipse & solar conjunction periods Doppler range & Delta-DOR tracking requirements Instrument Operations (During Cruise)

Power On/Off, Data Transfers Solar encounter operations (SOCs)

Orbital operations template created to capture and schedule these activities

Orbit activity planning process under development to coordinate s/c activities with instrument teams



Orbit Activity Planning Process

Orbit Planning Team (OPT)S/C

ENGRNAV Mission

DesignDSN Mission

Ops

FIELDS ISIS ProjectScientist

SWEAP WISPR

Orbital Operations Template (OOT)Venus Fly-Bys, Solar Encounter Periods, TCMs,

HGA Downlink Periods, S/C Mode Changes, Eclipse Periods, DSN Contacts, Solar

Conjunctions, Instrument Power On Periods,Routine and Special S/C Activities

Science Working Group (SWG)

Payload Orbital Operations Template (POOT)Power On/Off Times for each instrument

Instrument Real-Time Activities

OPTOOT Review

SWG

OOTDistributed

Incorporate Changes from Review

Integrated OOT & POOT

Create/Update OOT

Deliver OOT to SWG

Create/Update POOT

Deliver POOT to OPT

Merge OOT & POOT

No Changes Needed

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Challenges for Science Planningon Solar Probe Plus

Managing the data on the instrument SSR and instrument part of the spacecraft SSR

Limited uplink and downlink opportunities on some orbits Limited time to react to survey data and create commands to

transfer data from the instrument SSR to the spacecraft SSR

Solution: Create interactive display and analysis tool to integrate orbit

operations template information with instrument specific information as an aid to planning

Use a file priority scheme optimized for orbit type, to downlink high priority survey data quickly

This would maximize the reaction time that the instrument teams have to analyze data and create commands to transfer over the data from the instrument SSR to the spacecraft SSR

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Science Planning Steps

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Science Planning – Initial Pass

Science Planning – Second Pass

Orbit Operations Template (MOC)-S/C Activities-Uplinks/Downlinks-Power On/Off Periods

Science Activities (Inst. Teams)

Data Allocations (SWG)

Timed Science Activities-Fit in on/off periods-Manage instrument and S/C SSR data

Convert Activities into Command Files

MOCS/C

TLM

CmdFl

SOC ArchiveFor Processing

All Telemetry

Survey Telemetry

Constraint Checked Command Files



Orbit Types

Orbit Type Description Orbits

Good Greater than 20 days between survey and selected data downlink

8, 9, 12, 13, 15, 17, 19, 21, 23

Limited Downlink Between 10 and 20 days between survey and selected data downlink

2, 3, 6

Fast Downlink Less than 10 days between survey and selected data downlink

5, 24

Downlink Over 2 Orbits Not all data downlinked during orbit

7, 10, 11, 14, 18, 22

Downlink Over 2 OrbitsWith little or no Ka-band

Not all data downlinked during orbit with little or no Ka-band downlink

1, 4, 16, 20

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Draft Data Products

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Data Products (1/3)

Level FIELDS SWEAP ISIS WISPR

L0 Raw telemetry produced by SPP MOCPossibly 24-hour, APID-separated cleaned, sorted. PTP and SSR binary files

Raw Telemetry (Raw de-commutated telemetry received from MOC)

Raw telemetry packets, including HK, CMD-response rates, and event packets

Raw telemetry (CCSDS data packets)

L1 Uncompressed and decommutated L0 + time tagged waveform and spectral data in telemetry and engineering units [V, dBs, nT] in spacecraft coordinate systems. Data affinity groups. CDFs (one per subsystem per day). Quick look and daily/orbital summary plots

Instrument Count Rates (SPANs)

Instrument Currents (SPC)

Time series of uncalibrated instrument science and engineering rates at highest resolution.Unpacked particle event data.

FITS files with uncompressed images. Image values are in raw counts (DN).

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Data Products (2/3)


L2 L1 + Time-tagged waveform and spectral data in fully calibrated physical units [V, mV/m, nT, (V/m)2/Hz, nT2/Hz] in spacecraft and heliophysical coordinate systems. CDFs.Quick Look and daily/ orbital summary plots.

Calibrated Particle flux (in physical coordinates & units)Solar Wind moments and energy spectra(Calculated onboard, calibrated, in physical coordinates & units)

Time series of calibrated particle intensities at highest time, energy, and look-direction resolution, in physical units.

FITS files with calibrations applied. Image values are in units of brightness.

L3 L2 + VxB removal for DC E-field measurement, offsets and corrections with data quality flags.Plasma density. Spacecraft potential. Merged B.Merged density and temperature (FIELDS-SWEAP)CDFs, Science data plots

Solar wind bulk parameters, energy spectra, and electron pitch angle distribution (Calibrated and calculated on the ground)

Time series of calibrated particle intensities, averaged into (TBD) appropriate sets of larger time, energy and look-direction bins.Time-series plots of the above items.

Data products are the result of combining two or more images (movies, Carrington maps, etc). May or may not be calibrated in physical units.

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Data Products (3/3)


L4 Event (shocks, current sheets, radio bursts, stream interaction regions) time tags and parameters.Ad hoc.

Derived power spectra, source location, and event lists

Particle spectra and fluences for specific events and/or periods. Particle anisotropy parameters/plots. Others TBR.

Derived quantities (electron densities, CME masses etc).

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Back-up Slides

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SPP Investigations to Answer the Science Questions

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Investigation Instruments Measurements

Fields Experiment (FIELDS) – S. Bale, Univ. of California, Berkeley

4 x Electric Antennas2 x Fluxgate Magnetometer (MAG)1 x Search Coil Magnetometer (SCM)

electric & magnetic fields and waves, Poynting flux, absolute plasma density & electron temperature, spacecraft floating potential & density fluctuations, & radio emissions

Integrated Science Investigation of the Sun (ISIS) – D. McComas, Southwest Research Institute

High energy Energetic Particle Instrument (EPI-Hi)Low energy Energetic Particle Instrument (EPI-Lo)

energetic electrons, protons and heavy ions (10s of keV to ~100 MeV)

Solar Wind Electrons Alphas and Protons (SWEAP) - J. Kasper, Smithsonian Astrophysical Observatory

Solar Probe Cup (SPC)2 Solar Probe ANalyzers (SPAN)

velocity, density, and temperature of solar wind electrons, protons and helium ions

Wide-field Imager for Solar PRobe (WISPR) – R. Howard, Naval Research Laboratiry

White light imager images the solar wind, shocks and other structures in the solar corona and inner heliosphere

Heliospheric Origins with Solar Probe Plus (HeliOSPP) – M. Velli, Jet Propulsion Laborar

Observatory Scientist addresses SPP science objectives via multi-instrument data analysis and provides independent advice to optimize the scientific productivity of the mission



FIELDS Notional Operations (1)

1 As SPP descends toward perihelion (e.g. ~8 days prior), FIELDS is set into Calibration mode (~2 kbps). After Calibration, antenna bias sweeps measure properties of the sensors (pre-encounter). Ground operators verify that the Absolute Time Sequence is loaded and operating

2 At ~ 6 days to perihelion, FIELDS enters high rate science mode, sending 10 Gb of prioritized survey data to s/c SSR in real-time, while it stores about 30 Gb of High Rate Science data to an on-board 32GB FIELDS High- Rate Recorder

3 After encounter, FIELDS is commanded into Calibration mode followed by post-encounter Antenna bias sweeps (~few hours (TBR)). FIELDS returns to low rate Survey mode and is turned off

4 While off, FIELDS sensors use survival heaters to keep within their survival T limits. As downlink opportunities approach, s/c transmits prioritized Survey data from s/c SSR to the ground

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FIELDS Notional Operations (2)

5 FIELDS SOC processes and performs preliminary analyses on Prioritized Survey data, including Quick Look plots, and distributing to the team

6 At aphelion, FIELDS team convenes to examine the playback data and determine periods of special interest from preceding perihelion. Command sequences are generated to select special data for playback as SPP approaches the next perihelion. Team may prepare modes of operation for the next encounter and identify configuration or software changes needed

7 Following event selection, commands are sent to playback sections of the FIELDS High-Rate Recorder to the s/c SSR, and s/c forwards the data to the ground, in step 8. Commands sequences for next perihelion pass are sent to MOC for uplink

8 FIELDS high rate data is available for transmission from the Spacecraft SSR to the ground. FIELDS operates in low-rate survey mode, as permitted by operational constraints

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SWEAP Notional Operations (1)

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SWEAP Notional Operations (2)

Three main operational states affect instrument power consumption and dissipation: Safe state Low power state Science state

All other states vary in data accumulation rates, but consume/ dissipate same amount of power

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SWEAP Notional Ops (3)

High rate data transfer approach: After the encounter, the 10 Gb survey data is downlinked to ground

and SWEAP team transfers it from the MOC within 1 day of downlink After the data of interest is selected (~27 days), the SWEAP team

commands its instrument at the next uplink opportunity to select and start high rate transfer to the s/c SSR

Effective time to transfer data is ~12 h, SWEM powered on, SPC & SPAN A/B are off with survival heaters on

Full resolution data is downlinked depending on the s/c telemetry rate

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WISPR Notional Operations (1)

Standard image capture approach is to take <20 s exposures and sum them to achieve required integration times, using on-board processing for image summing and “cosmic ray” scrubbing

Usually, the instrument is in synoptic observing mode, with similar observations conducted each orbit using preplanned schedules uploaded for each encounter

Special observations tailored for specific science objectives are conducted on selected orbits (e.g. close to min perihelion, or favorable geometries of other missions)

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• Example of WISPR encounter science campaign

• WISPR 64 Gb flash memory buffers the data during encounter to fit within the data rates allocated by the spacecraft

• Once the data is transferred to SSR, it is downlinked



WISPR Notional Operations (2) Calibrations Limited set of observations are planned to perform instrument checkout and

calibration following instrument turn-on on approach to each solar encounter Cadence of images: a few images per day for up to ten days while the s/c

distance from the Sun is <0.5 AU on the inbound segment of each orbit Images may involve small off-points of the s/c from the Sun (up to a few arc

minutes) to verify the stray light performance of the instrument Depending on the downlink availability, the acquired data should be

downlinked prior to the solar encounter period for planning purposes WISPR uses selected background stars in the images for absolute calibration by

comparison to star catalog positions and magnitudes Based on the wide FOV of WISPR, no s/c maneuver is required to capture a

standard set of calibration stars Calibrations are used to verify the photometric calibration performed on the

ground before launch, and to measure the WISPR telescope throughput loss during the mission

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ISIS Notional Operations Below <0.25 AU EPI-Hi & EPI-Lo operate in their normal science mode

Both EPI-Hi & EPI-Lo are powered on and are acquiring data at high data collection rate, with occasional burst mode

EPI-Hi transfers the data to the SSR immediately, and EPI-Lo buffers the data and then transfers it over to SSR

Outside of 0.25 AU, EPI-Hi & EPI-Lo operate in their calibration mode, when the s/c is not in a power or operationally constrained mode The goal is to acquire data during a large SEP event that would help set

the energy thresholds for sorting data of various compositions Data collection rate is reduced Need to command ISIS late post encounter

Additional modes of operation are in process of being defined: software upload mode, and safe mode

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Good Orbit

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Limited Time Between P6 and P8> 20 days

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All Data Comes Down Fast with Little Time to Command

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Data Takes 2 Orbits to Come Down

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Data Takes 2 Orbits To Come Down with Little Ka Band DL

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Data Downlink Priority Scheme

Pr. % 85 Gbits

Type FIELDS (20 Gbits/orbit)

ISIS (12 Gbits/orbit)

SWEAP (20 Gbits/orbit)

WISPR (23 Gbits/orbit)

0 High Priority Usage / Commissioning / I&T

1 1 % S/C HK &Inst. High Priority HK

1 % 1 % 1 % 1 %

2 0.7 % Quicklook & Survey 1 % 1 % 1 %

3 Acclaimed Science All teams agree

4 28.3 % Survey & Inst. HK 50 % 50 % 6 %

5 Place Holder

6 44.6 % Science & Inst. HK 98 % 93 %

7 Place Holder

8 25.4 % Science & Inst. HK 48 % 48 %

9 Cruise Sci & Inst. HK

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Mission Operations Functional Interfaces

Mission Design

APL

Mission OperationsCenter (MOC)

APL

Deep SpaceNetwork (DSN)

JPL

Navigation

JPL

Spacecraft Engineering

APL

Mission Management & System Engineering

APL

OD solutionsEphemeris

Tracking Requests

Maneuver Plans

Maneuver Plans

Tra

ck

ing

Da

ta

Mis

sio

nS

ch

ed

ule

Technical ApprovalsCCB

TelemetryMonitor Data

S/C & Payload Commands

S/C

Tre

nd

ing

Mo

de

lsC

on

str

ain

ts

PayloadCommands

ScheduleRequests

Payload H/K Telemetry

Science Data

Sc

ien

ce

Re

qu

ire

me

nts

Attitude DataSmall Forces

Orbital OperationsTemplates (OOTs)

S/C

Ac

tiv

ity

Re

qu

es

ts

DSN schedule

MOC Data Server

Science Team

SWEAP

FIELDS

Science OperationsCenters (SOCs)

WISPR

ISIS

Science Gateway

Community

NRL

UCB

SAO

UNHLevel-0 Data

MOC Data Products

MO

C D

ata

Pro

du

cts

Science SurveyProducts

Sc

ien

ce

D

ata

Ke

y P

ara

me

ters

Da

ta



SPP Data Products

OPS PLANNING• Contact Plan

• DSN Keyword File (DKF)

• Graphical Timeline

• Orbit Ops Template

• FAST/Sched reports

• Att Short Term Predict

• Att Metakernel

• Leap Second Kernel

• Anomaly History Report

• As Flown Contact Report

• Archive Change Report

• Span Report

• Gap Report

• Command History Report

• Event History Report

• Inst Cmd History Report

• Inst Telem Alarm Notice

• Level 0 RT Telemetry

• Raw SSR Files

• SC/Gnd Telem Dictionary

• Weekly MOC Status

• Att Hist Report

• Ops SCLK Kernel

• Time History File

NAV/MD• Planetary Ephem• Predicted S/C Ephem• Mission S/C Ephem• Reconstructed S/C Ephem• Orbit Events Predicts• Maneuver Plan

SOC• Instr Telem Dictionary

• Weekly Inst Status ENG• S/C Activity Request

• RF Scheduler Inputs

• Maneuver Parameters

• Small Forces File

• Att Long Term Predict

• Frame Kernel (FK)

DSN• Stn Allocation File (SAF)• Tracking Data

• Flight Data • Planning Data • Navigation Data

solar probe plus a nasa mission to touch the sun solar probe plus science workshop march 26, 2013...

Documents

solar probe

solar corona

temperature of solar

nasa mission

reference mission

science questions

science workshop

detailed science objectives