Exploring the Sun-Heliosphere Connection Solar Orbiter Exploring the Sun-Heliosphere Connection

Solar Orbiter Exploring the Sun-Heliosphere Connection 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 Overarching Science Question • How does the Sun create and control Solar Orbiter the Heliosphere – and why does solar activity change with time? Solar Orbiter Exploring the Sun-Heliosphere Connection

Remote-sensing windows High-latitude(10 days each) Observations Mission Summary High-latitude Observations Planned Launch: Feb 2020 Cruise Phase: 1.8 years (for Feb 2020) 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 a complete solar rotation High-latitude Observations High-latitude Observations Solar Orbiter Exploring the Sun-Heliosphere Connection

Solar Orbiter is a mission designed to observe the Sun and the heliosphere, and link heliospheric phenomena back to their sources on the Sun. active region 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 . The Sun in Comparison

! What’s the mass of the Sun?

30 • 2×10 kg, or 333 000 times the Earth’s mass! That is 99.86% of the mass of the entire solar system. ! What is the Sun made of? • 78% hydrogen, 20% helium, and 2% heavier elements

Sunspots are regions of strong magnetic field SST/Royal Swedish Academy of Sciences/ V. M. de Jorge Henriques Solar activity changes with time - but what drives the solar cycle?

• 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 - but why?

M. Ow ens, Uni versi ty of Reading The Sun’s Magnetic Field: Main Driver of Space Weather Coronal mass ejections (CMEs) can cause geomagnetic storms

• It takes a ‘CME’ 17–96 h to reach Earth • It disturbs the Earth’s magnetic field • Duration: from hours to days • Also creates disturbances in the Ionosphere Coronal mass ejections (CMEs) can cause geomagnetic storms

Credit: NASA SVS, https://svs.gsfc.nasa.gov/vis/a000000/a003900/a003902/ The Sun’s Dynamic Heliosphere: “Bastille Day Event”, 14 July 2000

SOHO LASCO coronagraphs + EIT UV imager

www.jhelioviewer.org X-Class Solar Flare, 6 September 2017

SOHO LASCO coronagraph + SDO AIA UV imager

www.jhelioviewer.org X-Class Solar Flare, 6 September 2017

SDO AIA UV imager (17.1 nm, Fe IX, 600 000 K)

www.jhelioviewer.org Solar Orbiter Exploring the Sun-Heliosphere Connection

Solar Orbiter is a mission designed to observe the Sun and the heliosphere, and link heliospheric phenomena back to their sources on the Sun. active region

Coronal Mass Ejection

Solar Energetic Particles 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: Müller et al., Solar Physics 285 (2013)High-latitude Observations Solar Orbiter Exploring the Sun-Heliosphere Connection

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: Müller et al., Solar Physics 285 (2013)High-latitude • Coronal imaging 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 The Spacecraft

Instrument Boom

Tiltable Solar Arrays

Heat Shield with Aperture Doors

High-Gain Antenna

RPW Antennae Solar Orbiter in the Thermal Vacuum Chamber

Instrument Boom

Tiltable Solar Arrays

Heat Shield with Aperture Doors

High-Gain Antenna

RPW Antennae Credit: ESA/Airbus/IABG The Solar Orbiter Spacecraft on the Shaker

Instrument Boom

Tiltable Solar Arrays

Heat Shield with Aperture Doors

High-Gain Antenna

RPW Antennae Credit: ESA/Airbus/IABG Solar Orbiter - Magnetic Tests

Credit: ESA/Airbus/IABG Solar Orbiter - Getting Ready for Launch in February 2020

Instrument Boom

Tiltable Solar Arrays

Heat Shield with Aperture Doors

High-Gain Antenna

This picture shows the NASA New Horizon’s spacecraft on Launch pad 41 at Cape Canaveral Space Station, the same pad from which SolarRPW Orbiter Antennae will launch. https://commons.wikimedia.org/wiki/File:Atlas_V_551_at_Launch_Pad_41.jpg Solar Orbiter Exploring the Sun-Heliosphere Connection

High-latitude Summary Observations • Solar Orbiter: • ESA’s first solar and heliospheric science mission since SOHO (launched in 1995). • Will take the first pictures of the solar polar Perihelion regions, key to understanding the solar cycle Observations • Will provide multi-wavelength, high-resolution images of the Sun and its corona • Will measure the solar wind in situ • Excellent opportunities for joint science with NASA’s Parker Solar Probe, as well as other missions and observatories. • Solar Orbiter is on track for launch from Cape Canaveral in February 2020.

High-latitude Go Solar Orbiter! Observations