Third Time Around – Ulysses Over the North Solar Pole John Cooper (GSFC) – Introduction

Bob MacDowall (GSFC): PI, Ulysses radio & plasma wave instrument

Contact: robert.macdowall@nasa.gov

Ulysses: an ESA/NASA mission

• Spacecraft built by Dornier, managed by ESA

• Launch October 1990 provided by NASA

• Data acquisition (DSN, etc.) provided by NASA/JPL

• 10 instrument suites with roughly equal contributions from the U.S. and Europe

• Magnetometer (VHM/FGM) • Solar Wind Plasma Experiment (SWOOPS) • Solar Wind Ion Composition Instrument (SWICS) • Unified Radio and Plasma Wave Instrument (URAP) • Energetic Particle Instrument (EPAC)• Interstellar Neutral-Gas Experiment (GAS) • Low-Energy Ion and Electron Experiment (HISCALE) • Cosmic Ray and Solar Particle Instrument (COSPIN) • Solar X-ray and Cosmic Gamma-Ray Burst Instrument (GRB) • Dust Experiment (DUST) • Coronal-Sounding Experiment (SCE)• Gravitational Wave Experiment (GWE)

Ulysses has many scientific targets!

Three orbits: Cycle 22 (solar min), Cycle 23 (solar max), Cycle 23 (solar min)

• Solar wind velocity on polar plot at angle corresponding to Ulysses heliolatitude

• Time evolution of spacecraft is COUNTER-clockwise for each panel• Magnetic field polarity indicated by color: red ( outward), blue (inward)

A schematic of type II & type III

SOHO/LASCO/C2

Western behind-limb CME causes shock & type II radio

burst to pass Ulysses

Earth

Ulysses CME

Ecliptic plane

Type III source directions from high latitudes (1994): direct evidence of Parker spiral

Waves in magnetic holes – common in fast solar wind

Energetic particle “reservoirs” extend to the highest heliographic latitudes

Comets, e.g. Comet McNaught

Also comets:- Hyakutake- McNaught-Hartley

Ulysses Jupiter Flyby – February 1992

Highest magnetic latitude (48°) Io torus

Gladstone et al., 2001

Ulysses URAP Radio Data: 1992/04/10(jovicentric latitude = ~38°) Quasiperiodic bursts (QP-40)

a Chandra x-rays

Ulysses sees intense terrestrial auroral kilometric radiation (AKR) – 2006-2007

SOLAR ORBITER

Assisted by a series of Venus swing-bys, the spacecraft's 150-day orbit will evolve gradually over the mission lifetime from an inclination of about 12 to 35 degrees to the solar equator.

Solar Orbiter Baseline Payload:• Solar wind plasma analyzer• Radio & plasma wave analyzer• Magnetometer• Energetic particle detector• Dust particle detector• Neutron Gamma ray detector• Visible image & Magnetograph• EUV spectrometer• EUV imager• VIS-EUV coronagraph• X-ray imaging spectrometer

“High Priority” Augmentations• Neutral particle detector• Coronal radio sounder• Dust composition analyzer

Closest perihelion: 48 solar radii3-axis stabilized spacecraftProtected by sun shield; receives a maximum of 25x solar radiation at 1 AUPlanned launch ~2015

Proposed that NASA Inner Heliospheric Sentinels would fly at the same time to maximize scientific return; joint program referred to as HELEX.

Summary• Ulysses spacecraft has a highly-inclined orbit (i=79°) to permit study

of the regions over the poles of the sun• Ulysses has provided many new results on high-latitude (fast) solar

wind evolution and composition• Radio astronomy data permit the tracking of solar radio burst and

serve as proxies for shocks, CMEs, and other solar activity• Ulysses energetic particle data show that major particle events fill the

entire heliosphere, to the highest heliolatitudes, creating a reservoir of energetic particles

• Ulysses has also visited the polar regions of Jupiter, with discoveries that include periodic radio, x-ray, and relativistic electron bursts

• In 2006 and 2007, Ulysses’ latitude scan around perihelion brought it close enough to Earth so that terrestrial auroral kilometric radio emission was observed daily

• Solar Orbiter will launch ~2015 and observe the sun from as close as 48 solar radii