Exploring the Sun-Heliosphere Connection Solar Orbiter

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Exploring the Sun-Heliosphere Connection Solar Orbiter Solar Orbiter Exploring the Sun-Heliosphere Connection Daniel Müller ESA Solar Orbiter Project Scientist Holly Gilbert NASA Deputy Solar Orbiter Project Scientist Solar Orbiter Exploring the Sun-Heliosphere Connection Solar Orbiter • First medium-class mission of ESA’s Cosmic Vision 2015-2025 programme, implemented jointly with NASA Ulysses • Dedicated payload of 10 remote-sensing and in-situ instruments measuring from the photosphere into the solar wind SOHO Solar Orbiter Solar Orbiter Solar Orbiter Exploring the Sun-Heliosphere Connection Solar Orbiter • First medium-class mission of ESA’s Cosmic Vision 2015-2025 programme, implemented jointly with NASA Ulysses • Dedicated payload of 10 remote-sensing and in-situ instruments measuring from the photosphere into the solar wind Overarching Science Question SOHO • How does the Sun create and control Solar Orbiter Solar Orbiter the heliosphere – and why does solar activity change with time? Solar Orbiter Exploring the Sun-Heliosphere Connection Solar Orbiter • First medium-class mission of ESA’s Cosmic Vision 2015-2025 programme, implemented jointly with NASA Ulysses • Dedicated payload of 10 remote-sensing and in-situ instruments measuring from the photosphere into the solar wind Overarching Science Question Bow shock aroundSOHO young star LL Ori, Hubble image • How does the Sun create and control Solar Orbiter Solar Orbiter the heliosphere – and why does solar activity change with time? The Sun in a Nutshell Internal Structure: inner core radiative zone convection zone Photosphere ~6000 K Tcore=15.7·106 K Earth to scale Chromosphere ~104 K Corona >106 K The Sun - A Fusion Reactor During this reaction, Each second, the Sun the remaining mass is fuses 620 million tons converted into energy of hydrogen into 606 according to Einstein’s million tons of helium. formula E = mc2 . Solar activity changes with time • Inside the Sun, moving charges generate magnetic field • Solar Dynamo: Field amplification at the base of the convection zone • Bundles of intense magnetic field rise to the Sun’s surface due to magnetic buoyancy → Sunspots • Sunspot Cycle: Period of ~11 years M. Owens, University of Reading The Sun’s Magnetic Field: Main Driver of Space Weather Solar Orbiter Exploring the Sun-Heliosphere Connection Remote-sensing windows High-latitude(10 days each) Observations Mission Summary High-latitude Observations Launch: Feb 2020 Cruise Phase: 1.8 years Nominal Mission: 4 years Perihelion Observations Extended Mission: 3.5 years Orbit: 0.28–0.91 AU (P=150-180 days) Out-of-Ecliptic View: Multiple gravity assists with Venus to increase inclination out of the ecliptic to >24° (nominal mission), >33° (extended mission) Perihelion Reduced relative rotation: Observations Observations of evolving structures on solar surface & in heliosphere for almost High-latitude a complete solar rotation Observations High-latitude Observations Solar Orbiter - Solar latitude and distance Solar Orbiter Exploring the Sun-Heliosphere Connection Top-level Science Objectives High-latitude Observations 1. What drives the solar wind and where does the coronal magnetic field originate? 2. How do solar transients drive heliospheric variability? 3. How do solar eruptions produce energetic particle radiation that fills the heliosphere? Perihelion 4. How does the solar dynamo work and drive Observations connections between the Sun and the heliosphere? Mission overview: MüllerHigh-latitude et al., Solar Physics 285 (2013)Observations Solar Orbiter Exploring the Sun-Heliosphere Connection Top-level Science Objectives High-latitude Observations 1. What drives the solar wind and where does the coronal magnetic field originate? 2. How do solar transients drive heliospheric variability? 3. How do solar eruptions produce energetic particle radiation that fills the heliosphere? Perihelion 4. How does the solar dynamo work and drive Observations connections between the Sun and the heliosphere? Observations • In-situ: Measurements of the solar wind plasma, fields, waves and energetic particles as close as 0.28 AU • Remote-sensing: • Simultaneous high-resolution imaging and spectroscopic observations of the Sun in and out of the ecliptic plane. • Vector magnetic field of solar photosphere • Full-disk imaging in visible, UV, X-rays Mission overview: MüllerHigh-latitude et al., • Coronal imaging Solar Physics 285 (2013)Observations Solar Orbiter Payload In-Situ Instruments J. Rodríguez- Composition, timing and distribution functions of EPD Energetic Particle Detector Pacheco energetic particles High-precision measurements of the heliospheric MAG Magnetometer T. Horbury magnetic field Electromagnetic and electrostatic waves, magnetic RPW Radio & Plasma Waves M. Maksimovic and electric fields at high time resolution Sampling protons, electrons and heavy ions in the SWA Solar Wind Analyser C. Owen solar wind Remote-Sensing Instruments High-resolution and full-disk (E)UV imaging of the on- EUI Extreme Ultraviolet Imager P. Rochus disk corona METIS Coronagraph M. Romoli Visible and UV Imaging of the off-disk corona PHI Polarimetric & Helioseismic S. Solanki High-resolution vector magnetic field, line-of-sight Imager velocity in photosphere, visible imaging SoloHI Heliospheric Imager R. Howard Wide-field visible imaging of the solar off-disk corona SPICE Spectral Imaging of the ESA facility EUV imaging spectroscopy of the solar disk and near- Coronal Environment instrument Sun corona STIX Spectrometer/Telescope for S. Krucker Imaging spectroscopy of solar X-ray emission Imaging X-rays Solar Orbiter Exploring the Sun-Heliosphere Connection High-latitude Observations Summary • Solar Orbiter: • ESA’s first solar and heliospheric science mission since SOHO (launched in 1995). Perihelion • Will provide multi-wavelength, high-resolution Observations images of the Sun and its corona • Will measure the solar wind in situ • Will take the first pictures of the solar polar regions, key to understanding the solar cycle • Excellent opportunities for joint science with NASA’s Parker Solar Probe, as well as other missions and observatories. Mission overview: MüllerHigh-latitude et al., Solar Physics 285 (2013)Observations The Sun’s Dynamic Heliosphere SOHO LASCO coronagraphs + EIT UV imager, “Bastille Day Event”, 14 July 2000 www.jhelioviewer.org.
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