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B. Klecker

Max-Planck-Institut für extraterrestrische Physik, 85740 Garching, Germany

Kennebunkport, MN

June 9, 2010

SOHO OVERVIEW

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• The Beginning: SOHO & CLUSTER, the First Cornerstone of

ESA’s Horizon 2000 Program

• SOHO Instruments & Observations

• Present Status and Future Operations

• SOHO Bibliometrics

• Public Access to SOHO Data / Archive

OVERVIEW

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HORIZON 2000 PROGRAMCORNERSTONE 1: SOHO & CLUSTER

Investigation of the Sun, SEPs, Solar Wind

Launch: 2 December 1995

SOlar and Heliospheric Observatory CLUSTER

Multispacecraft Mission with4 S/C with identical Instrumentation

Launch Attempt with Ariane 5 01: 1996Repeat with 2 Soyuz in 2000

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SOHO INSTRUMENTS

• CDS (Coronal Diagnostic Spectrometer)

• CELIAS (Charge, Element, and Isotope Analysis System

• COSTEP (Comprehensive Suprathermal and Energetic Particle Analyzer)

• EIT (Extreme ultraviolet Imaging Telescope),

• ERNE (Energetic and Relativistic Nuclei and Electron experiment)

• GOLF (Global Oscillations at Low Frequencies)

• LASCO (Large Angle and Spectrometric Coronagraph)

• MDI/SOI (Michelson Doppler Imager/Solar Oscillations

Investigation)

• SUMER (Solar Ultraviolet Measurements of Emitted

Radiation)

• SWAN (Solar Wind Anisotropies)

• UVCS (Ultraviolet Coronagraph Spectrometer)• VIRGO (Variability of Solar Irradiance and Gravity Oscillations)

• In-Situ

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SOHO OBSERVATIONS: UVCS

Serendipity: Sungrazing Comets

More than 1000 Sungrazig Comets Observed

Comet Outgassing

Evidence for dust sublimation in UVCS Spectra

• Derived outgassing rates of 0.7 - 3.9 x 106

g/s (Si) and 1.7 - 15 x 104 g/s (C)

• If the Si atoms originate in the evaporation of molecules of forsterite or olivine, mass loss rate from dust is ~ 4 - 50 x 106 g/s

• All grains < 12 cm in diameter likely to evaporate in < 10 min at observed distance of 3.37 solar radii

Ciaravella et al., 2010

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SOHO OBSERVATIONS: MDIHELIOSEISMOLOGY - Access to the Solar Interior

R/RS

2D Inversion results for the sound speed perturbation near the tachoclyne; Making the Transition between radiation zone and convection zone visible

Latitudinal Average

Longitudinal Average

Zhao et al,2009

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SOHO OBSERVATIONS: VIRGOTotal Solar Irradiance (TSI)

TSI and Br

TSI

Open Magnetic Flux

SOHO

Senior Review 2010

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SOHO EITExtreme Ultraviolet Imaging Telescope

Active Regions at the Sun and their relation to SEPs

EIT SEP Intensity-Time Profiles

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COROTATING INTERACTION REGIONS (CIRs)Events Related to High Speed Streams from Coronal

Holes (UVCS)

In the Ecliptic: High Speed Streams from Mid and Low Latitude Coronal Holes

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SOHO CDSCoronal Diagnostic Spectrometer

EITFOV

Investigating the Solar Atmosphere

• Elemental abundances from line intensities• Magnetoacoustic waves in the transition region and corona

Using simultaneous CDS measurements of oscillations in pairs of lines formed at transition region and coronal temperatures, O’Shea et al. (2006) found evidence for outward-propagating waves above the solar poles.

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SOHO LASCOLarge Angle Spectroscopic Coronograph

CME Variability 1996 - 2010

Now more than 1 Solar Cycle

Gopalswamy, 2007

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ACCELERATION AT INTERPLANETARY SHOCKSCMES, ICMES AND CME-DRIVEN SHOCKS

ICMECME

SOHO / LASCO Zurbuchen & Richardson, 2006

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ERNE / COSTEP

Energetic & Relativistic Nuclei & Electron experiment /

Comprehensive Suprathermal & Energetic Particle analyser

• SEPs and their Source

• SEP Composition (3He/4He)

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CELIAS / MTOFSolar Wind Isotopic Composition

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PRESENT STATUS AND FUTURE OPERATION 2011 and Beyond

Continue LASCO Coronograph (not on SDO)

Continue MDI in 2010 for Intercalibration with SDO/HMI (i.e. turn MDI off 2011)

FY 2010: Transition from SOHO to ‘Bogart’

FY 2011 and later: Science Funding for US Science Teams phased out.

ESA: SOHO approved to end of 2012

NASA PLAN

Present

All Instruments are operated

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SOHO BIBLIOMETRICS

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PUBLIC ACCESS TO SOHO DATA / ARCHIVE