Bernhard FleckSOHO Project Scientistbfleck@esa.nascom.nasa.gov

SOHO Science OperationsNow and Then

Outline

Mission overview Science operations setup

• Experimenters’ Operations Facility (EOF)• Planning process• SOHO Joint Observing Plans (JOPs)• SOHO Science Operations Coordinators (SOCs)

Data processing, archiving and data distribution SOHO science operations now Summary / lessons learned

SOHO – quick facts

Joint ESA/NASA missionBuilt in Europe, launched by NASA (2 Dec 1995)Operated from NASA/GSFCOrbits around L1Nominal mission: 2 years12 instruments aboard

SOHO’s science objectives

A) Solar InteriorWhat are its structure and dynamics?

B) Solar CoronaWhy does it exist and how is it heated?

C) Solar WindWhere is it accelerated and how?

Key results

First images of the interior of a star Coronal heating Solar wind acceleration Monitoring total solar irradiance

(‘solar constant’) and EUV flux Revolutionized our ability to forecast

‘space weather’ Discovered over 2000 comets

SOHO Experimenters’ Operations Facility

Located at NASA/GSFC, next to SOHO MOC• Co-location of experiment teams and SOHO FOT• Proved to be very beneficial (a) operational, b) public affairs / tour groups)

Heritage from earlier solar physics missions: OSO, Skylab, SMM Focal point for mission science planning and instrument operations

• Became “Mecca of Solar Physics”• Influenced a whole generation of solar physicists

Reception of real-time and playback telemetry Data processing to determine instrument commands Near real-time commanding directly from instrumenters’

workstations• Resembles more operations of a ground-based observatory than operations of a

conventional space-based observatory• Allows for quick reaction to targets of opportunity (re-pointing)

SOHO Experimenters’ Operations Facility

Meeting Room

SOCsPS

EITLASCO

UVCS

SUMERCDSMDI

SOHO Experimenters’ Operations Facility

Science planning

SOHO from the beginning conceived as a package of complementary instruments coordination critically important for mission success

“Maximizing immediate and future scientific output of all SOHO observations”• Unique input for numerical modeling of solar phenomena• Planned and ad hoc campaigns (co-observations)

Joint Observing Programs (JOPs)– Coherent observing plans to maximize the scientific return of the individual

instruments by coordinating their plans for the study of specific solar phenomena– Many JOPs involve collaborations with ground-based observatories or other space

missions– 227 science JOPs and 14 Intercalibration JOPs– http://soho.nascom.nasa.gov/soc/JOPs/– SOHO campaign database: 1307 records

Word Wide Web key tool for SOHO science operations from the very beginning Software planning and scheduling tool developed for SOHO (in IDL)

Science planning tool

Science planning process

Nested scheme: monthly, weekly, daily meetings, with strategic input from quarterly SWT meetings

• Quarterly SWT meetings:– Overall observing priorities – Major campaigns like “Whole Sun Month” – Policies regarding reaction to Major Flare Watches – Resolution of conflicts and disputes – Guest Investigator proposals

• Monthly meetings: – General observing plan for coming month by Science Operations Team (SOT)– Scheduling of campaigns and JOPs

• Weekly and daily meetings: – Refinements of monthly plan – Coordination with ground-based observatories – Final pointing up-dates

SOHO Science Operations Coordinators

1 ESA, 2 NASA (+ several student SOCs for off-hours and weekends) Interface between instrument teams and FOT Focal point-of-contact for joint observing campaigns with other space missions

and ground-based observatories Coordination of special operations

• S/C roll • S/C off-pointing • calibration rockets

Maintain long-term plan, campaign databases, etc. First priority: instrument health and safety

Flight Operations Team

SOC

CDSUVC

SLASCOEITMD

I

Instruments with constant operational presence at the EOF

Operations overview

Flight Operations Team

SOC

CDSUVC

SLASCOEITMD

I

TRACE TRACE is sometimes dubbed the 13th SOHO instrument, with constant EOF presence

Operations overview

Flight Operations Team

SOC

CDSUVC

SLASCOEITMD

I

SWAN

TRACE

SWAN team in Europe sends delayed command files to EOF. Present at EOF for “special operations” (engineering etc).

Operations overview

Flight Operations Team

SOC

CDS

SUMER

UVCSLASCOEITMD

I

SWAN

TRACE

SUMER operates only during special campaigns with EOF presence

Operations overview

Flight Operations Team

SOC

CDS

SUMER

UVCSLASCOEIT

GOLF

MDI

VIRGO

SWAN

TRACE

Particle Exp.

GOLF, VIRGO, CELIAS, ERNE, and COSTEP send delayed command files daily or weekly (if any at all).

Operations overview

Flight Operations Team

SOC

MEDOC

CDS

SUMER

UVCSLASCOEIT

GOLF

MDI

VIRGO

SWAN

TRACE

Particle Exp.

Multi-Experiment Data Operations Centre for SOHO (MEDOC)

“Sister EOF” at Institut d'Astrophysique Spatiale (IAS) in Orsay, France. Capability to send near-real-time commands, reception of real-time telemetry.

Hosts “MEDOC Campaigns” with most daily science planning, and some commanding, performed at MEDOC.

Operations overview

Flight Operations Team

SOC

MEDOC

CDS

SUMER

UVCSLASCOEIT

GOLF

MDI

VIRGO

SWAN

TRACEULYSSES

RHESSI

Yohkoh

Hinode

STEREO

Particle Exp.

Joint observations with other spacecraft……

Operations overview

Flight Operations Team

SOC

MEDOC

CDS

SUMER

UVCSLASCOEIT

GOLF

MDI

VIRGO

SWAN

TRACEULYSSES

RHESSI

Yohkoh

Hinode

STEREO

Particle Exp.

Operations overview

TenerifeLa Palma

Kitt PeakBig Bear

…and ground based observatories

Data processing

Telemetry (both real-time and recorder dumps) flow in real-time from DSN to SOHO EOF at GSFC

Data decompressed and reformatted in near real-time by PI teams and posted on SOHO pages

• More than 2/3 of over 2100 SOHO comets discovered by amateurs in SOHO real-time data

Final level-0 data produced by Data Distribution Facility with about 4 weeks delay

• Most data gaps and drop-outs filled by then• Original distribution on CD-ROMs• Since 1997 distribution through Internet

Data accessibility

Completely open data policy• “The Sun is shining for everybody”

All SOHO data available online through• SOHO archive• PI sites• Virtual Solar Observatory

Instrument resources pages• Software tools (IDL)• Calibration• Analysis• Key element for prompt and expedient data delivery by PI teams is the fact that we

do not require calibrated data for ingestion into archive, but raw data + calibration software (which can be easily updated)

SOHO Archive

Developed by ESA SOHO PS team at GSFC• Large variety of approaches in different PI teams• Difficult to homogenize system• Lesson learned: ESA involvement in planning process as early as possible

Content identical to that of PI teams• Exception: high-rate MDI data, which are stored only at Stanford

Current to within a few months after level-0 data deliver (Incomplete) European Mirror archives

• MEDOC, IAS Orsay, France• Univ. of Torino, Italy• RAL, UK• Lesson learned: very difficult for universities and other research groups to follow

through on such a long-term commitment New SOHO archive @ ESAC providing additional functionality Efforts underway for “final archive” (calibrated data)

SOHO science operations NOW

Budget cuts necessitated radical changes to SOHO science ops starting in early 2010 SOHO science ops now reduced to bare bones

• Then: service in a 3-star restaurant Now: McDonalds drive-through

SOHO EOF closed; no routine planning meetings anymore No SOC anymore All “self-serve” by PI teams Except LASCO/EIT all instruments are commanded remotely from home institutions SOHO PS single point-of-contact

Summary

Ops concept developed in the early 90ies proved to be successful and robust Science coordination key factor for the great success of SOHO Having a real science center very beneficial for the mission and the community

• No such focal point for STEREO, SDO or other planned solar missions Early adoption of the World Wide Web as key tool for coordination,

communication and data dissemination key decision Maintenance of hardware/software infrastructure for 16+ years challenging Open data policy to maximize the number of users

• Provision of both data and software tools• No requirements on PI teams to provide final, calibrated, archive-quality data• “living” archive

Start planning of science operations and data archiving as early as possible• Work with instrument teams from very beginning of a project

Team spirit: integrated instrumenters/FOT/NASA/ESA team Lights out ops working well so far

SOHO’s instruments