1. 1 B. Klecker Max-Planck-Institut für extraterrestrische Physik, 85740 Garching, Germany Kennebunkport, MN June 9, 2010 SOHO OVERVIEW

2. 2 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

3. 3 HORIZON 2000 PROGRAM CORNERSTONE 1: SOHO & CLUSTER Investigation of the Sun, SEPs, Solar Wind Launch: 2 December 1995 SOlar and Heliospheric Observatory CLUSTER Multispacecraft Mission with 4 S/C with identical Instrumentation Launch Attempt with Ariane 5 01: 1996 Repeat with 2 Soyuz in 2000

4. 4 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

5. 5 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 10 6 g/s (Si) and 1.7 - 15 x 10 4 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 10 6 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

6. 6 SOHO OBSERVATIONS: MDI HELIOSEISMOLOGY - Access to the Solar Interior R/R S 2D Inversion results for the sound speed perturbation near the tachoclyne; Making the Transition between radiation zone and convection zone visible Latitudinal AverageLongitudinal Average Zhao et al, 2009

7. 7 SOHO OBSERVATIONS: VIRGO Total Solar Irradiance (TSI) TSI and Br TSI Open Magnetic Flux SOHO Senior Review 2010

8. 8 SOHO EIT Extreme Ultraviolet Imaging Telescope Active Regions at the Sun and their relation to SEPs EITSEP Intensity-Time Profiles

9. 9 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

10. 10 SOHO CDS Coronal Diagnostic Spectrometer EIT FOV 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.

11. 11 SOHO LASCO Large Angle Spectroscopic Coronograph CME Variability 1996 - 2010 Now more than 1 Solar Cycle Gopalswamy, 2007

12. 12 ACCELERATION AT INTERPLANETARY SHOCKS CMES, ICMES AND CME-DRIVEN SHOCKS ICMECME SOHO / LASCOZurbuchen & Richardson, 2006

13. 13 ERNE / COSTEP Energetic & Relativistic Nuclei & Electron experiment / Comprehensive Suprathermal & Energetic Particle analyser SEPs and their Source SEP Composition ( 3 He/ 4 He)

14. 14 CELIAS / MTOF Solar Wind Isotopic Composition

15. 15 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

16. 16 SOHO BIBLIOMETRICS

17. 17 PUBLIC ACCESS TO SOHO DATA / ARCHIVE