The Sun and the Heliosphere in Three Dimensions

The Sun and the Heliosphere in Three Dimensions
Author: R.G. Marsden
Publisher: Springer Science & Business Media
Total Pages: 518
Release: 2012-12-06
Genre: Science
ISBN: 9400946120

The 19th ESLAB Symposium on 'The Sun and the Heliosphere in Three Dimensions' was held in Les Diablerets (Switzerland) on 4-6 June 1985. Organised almost exactly ten years after the Goddard Space Fl i ght Center Sympos i um dea 1 i ng with the Sun and the i nterp 1 anetary medium in three dimensions, the aim of this Symposium was not only to review the progress made in understanding the three-dimensional structure and dynamics of the heliosphere, but also to look ahead to the scientific return to be expected from the Ulysses mission. Scheduled for launch in May 1986, the scientific instrumentation on board Ulysses will shed light on the conditions and processes occurring away from the ecliptic plane, thereby adding literally a new dimension to our understanding of the only stellar plasmasphere to which we have direct access. The scientific programme of the Symposium was built around a series of invited review papers dealing with aspects of the corona and its influence on the interplanetary medium via transient ejecta, the solar wind, energetic solar particles and galactic cosmic rays, interplanetary dust and neutral gas. These invited talks were supplemented by a number of contributed and poster papers. With the exception of three contributed talks and Wibberenz' review of coronal and acceleration of energetic particles, all papers propagation presented at the Symposium are included in this volume.

The 3-D Heliosphere at Solar Maximum

The 3-D Heliosphere at Solar Maximum
Author: R.G. Marsden
Publisher: Springer Science & Business Media
Total Pages: 416
Release: 2013-03-14
Genre: Science
ISBN: 9401732302

Our knowledge of the heliosphere in three dimensions near solar minimum has advanced significantly in the last 10 years, largely as a result of the on-going ESAINASA Ulysses mission. Similar advances in our understanding of the global heliosphere near solar maximum are to be expected with the return of Ulysses to high solar latitudes in 2000/200 I. With this in mind, the 34th ESLAB Symposium, held at ESTEC in Noordwijk, The Netherlands, on 3-6 October, 2000, was devoted to 'The 3-D Heliosphere at Solar Maximum'. This was the third ESLAB Sympo sium focusing on the three-dimensional heliosphere (previous symposia being in 1985 and 1994), and the timing was particularly appropriate, marking as it did the 10th anniversary of the launch of the Ulysses spacecraft. Furthermore, Ulysses had just started its third high-latitude pass, the second over the Sun's south polar regions. The symposium addressed a wide range of topics related to the solar-maximum heliosphere, with presentations on many of the latest findings from Ulysses and other space-based missions. Ground-based studies and theoretical modeling were also well represented. Specific questions to which answers were sought included the following.

The STEREO Mission: A Three-Dimensional View of the Sun and Heliosphere

The STEREO Mission: A Three-Dimensional View of the Sun and Heliosphere
Author:
Publisher:
Total Pages: 4
Release: 2007
Genre:
ISBN:

Coronal mass ejections (CMEs) are massive outflows of material from the Sun's corona, traveling into the surrounding heliosphere at speeds up to 1000-2000 kilometers per second. When directed toward the Earth, CMEs can result in damage to satellites, enhanced auroral displays, blackouts of power grids on Earth, and interference with surface radio communications. The first CME detected from space was observed by an NRL coronagraph onboard the Seventh Orbiting Solar Observatory (OSO-7) in December 1971. Much of our recent knowledge of CMEs has been obtained from an NRL visible-light coronagraph (LASCO, the Large Angle Spectroscopic Coronagraph(2)) on the Solar and Heliospheric Observatory (SOHO) spacecraft, launched in 1995. But SOHO observes from only one viewpoint, leaving three-dimensional structure ambiguous for individual CMEs. The next step beyond SOHO is the Solar Terrestrial Relations Observatory (STEREO) mission, consisting of two spacecraft observing the Sun from two different viewpoints, allowing a three-dimensional view of the initiation of CMEs and their propagation outwards. In addition, STEREO will carry a new type of heliospheric coronagraph that is off-pointed from the solar disk, and can observe from the side the Sun-Earth line all the way out to Earth. The STEREO mission is meant to increase our understanding of such topics as solar structures and their properties involved in CME initiation; threedimensional structure and kinematics of CMEs; three-dimensional structure of active regions, coronal loops, and streamers; propagation of CMEs into the corona and interplanetary medium; and the effects of CMEs through the heliosphere to the Earth.

Three-dimensional Features of the Outer Heliosphere Due to Coupling Between the Interstellar and Interplanetary Magnetic Fields. IV. Solar Cycle Model Based on Ulysses Observations

Three-dimensional Features of the Outer Heliosphere Due to Coupling Between the Interstellar and Interplanetary Magnetic Fields. IV. Solar Cycle Model Based on Ulysses Observations
Author:
Publisher:
Total Pages:
Release: 2013
Genre:
ISBN:

The solar cycle has a profound influence on the solar wind (SW) interaction with the local interstellar medium (LISM) on more than one timescales. Also, there are substantial differences in individual solar cycle lengths and SW behavior within them. The presence of a slow SW belt, with a variable latitudinal extent changing within each solar cycle from rather small angles to 90°, separated from the fast wind that originates at coronal holes substantially affects plasma in the inner heliosheath (IHS)--the SW region between the termination shock (TS) and the heliopause (HP). The solar cycle may be the reason why the complicated flow structure is observed in the IHS by Voyager 1. Here, we show that a substantial decrease in the SW ram pressure observed by Ulysses between the TS crossings by Voyager 1 and 2 contributes significantly to the difference in the heliocentric distances at which these crossings occurred. The Ulysses spacecraft is the source of valuable information about the three-dimensional and time-dependent properties of the SW. Its unique fast latitudinal scans of the SW regions make it possible to create a solar cycle model based on the spacecraft in situ measurements. On the basis of our analysis of the Ulysses data over the entire life of the mission, we generated time-dependent boundary conditions at 10 AU from the Sun and applied our MHD-neutral model to perform a numerical simulation of the SW-LISM interaction. We analyzed the global variations in the interaction pattern, the excursions of the TS and the HP, and the details of the plasma and magnetic field distributions in the IHS. The resulting numbers are compared with Voyager data as functions of time in the spacecraft frame. We also discuss solar cycle effects which may be reasons for the recent decrease in the TS particles (ions accelerated to anomalous cosmic-ray energies) flux observed by Voyager 1.

Magnetohydrodynamic Modeling of the Solar Corona and Heliosphere

Magnetohydrodynamic Modeling of the Solar Corona and Heliosphere
Author: Xueshang Feng
Publisher: Springer
Total Pages: 772
Release: 2019-08-01
Genre: Science
ISBN: 9811390819

The book covers intimately all the topics necessary for the development of a robust magnetohydrodynamic (MHD) code within the framework of the cell-centered finite volume method (FVM) and its applications in space weather study. First, it presents a brief review of existing MHD models in studying solar corona and the heliosphere. Then it introduces the cell-centered FVM in three-dimensional computational domain. Finally, the book presents some applications of FVM to the MHD codes on spherical coordinates in various research fields of space weather, focusing on the development of the 3D Solar-InterPlanetary space-time Conservation Element and Solution Element (SIP-CESE) MHD model and its applications to space weather studies in various aspects. The book is written for senior undergraduates, graduate students, lecturers, engineers and researchers in solar-terrestrial physics, space weather theory, modeling, and prediction, computational fluid dynamics, and MHD simulations. It helps readers to fully understand and implement a robust and versatile MHD code based on the cell-centered FVM.

Solar Dynamics and its Effects on the Heliosphere and Earth

Solar Dynamics and its Effects on the Heliosphere and Earth
Author: Daniel Baker
Publisher: Springer Science & Business Media
Total Pages: 373
Release: 2007-11-24
Genre: Science
ISBN: 038769532X

This volume helps the reader to understand the ways and means of how dynamical phenomena are generated at the Sun, how they travel through the Heliosphere, and how they affect Earth. It provides an integrated account of the three principal chains of events all the way from the Sun to Earth: the normal solar wind, coronal mass ejections, and solar energetic particles.