Download or read book Studies Using Imp Voyager and Pioneer Cosmic Ray Data to Determine the Size of the Heliosphere written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-10-24 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this project was to use the cosmic ray data from the IMP, Voyager and Pioneer spacecraft in the heliosphere out to approximately 65 AU to estimate the size of the heliosphere. We used several techniques to develop a consistent picture of the size of the heliosphere. The first method used a response function approach which determined the intensity as a function of time by scaling the modulation effect as they move outward and eventually reach the boundary of the heliosphere. In this model the effects of transient cosmic ray disturbances is included. A second approach using the perturbation method in which drifts are considered as a perturbation to the standard diffusion-convection modulation models was not fully developed. In a third approach the location of the modulation boundary beyond the termination shock was estimated using observations of the intensity and radial gradients between Voyager 2 and Pioneer 10 along with new estimates of the interstellar intensity of more than 70 MeV galactic cosmic rays. Using this method we found that for 7 years, from 1983 to 1990, the modulation boundary remained constant at 83 +/- 5 AU. We infer from these studies that a modulation boundary can be estimated only by extrapolating the observed radial gradients when the solar magnetic field polarity is such that cosmic-ray particles are drifting in the heliosphere inward toward the Earth along the neutral sheet. The boundary distance is larger than the estimates of the location of the termination shock at 67 +/- 5 AU using the same method. Two other studies partially supported by this grant are attached. The first deals with the recovery period of the greater than 70 MeV cosmic rays in the outer heliosphere from 1992-1995. In the second paper we compare the rigidity dependence of the 11-year cosmic ray variation at the Earth in two cycles of opposite solar magnetic field polarity. Lockwood, John A. (Principal Investigator) Unspecified Center NAGW-3454
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1998-07 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1987 with total page 920 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Space Physics Strategy implementation Study written by and published by . This book was released on 1991 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA University Program Management Information System FY 1994 written by and published by . This book was released on 1994 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA University Program Management Information System FY 1993 written by and published by . This book was released on 1993 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA University Program Management Information System FY 1995 written by and published by . This book was released on 1995 with total page 672 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1987 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiannual, with semiannual and annual indexes. References to all scientific and technical literature coming from DOE, its laboratories, energy centers, and contractors. Includes all works deriving from DOE, other related government-sponsored information, and foreign nonnuclear information. Arranged under 39 categories, e.g., Biomedical sciences, basic studies; Biomedical sciences, applied studies; Health and safety; and Fusion energy. Entry gives bibliographical information and abstract. Corporate, author, subject, report number indexes.
Download or read book Literature 1985 Part 1 written by S. Böhme and published by Springer Science & Business Media. This book was released on 2013-12-11 with total page 1157 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astronomy and Astrophysics Abstracts aims to present a comprehensive documen tation of the literature concerning all aspects of astronomy, astrophysics, and their border fields. It is devoted to the recording, summarizing, and indexing of the relevant publications throughout the world. Astronomy and Astrophysics Abstracts is prepared by a special department of the Astronomisches Rechen-Institut under the auspices of the International Astronomical Union. Volume 39 records literature published in 1985 and received before August 15, 1985. Some older documents which we received late and which are not surveyed in earlier volumes are included too. We acknowledge with thanks contributions of our colleagues all over the world. We also express our gratitude to all organiza tions, observatories, and publishers which provide us with complimentary copies of their publications. On account of the introduction of an object index the scope of index information will be considerably enlarged beginning with this volume. In connection with the subject index an additional source to satisfy the needs of retrieval is opened up. Starting with Volume 33, all the recording, correction, and data processing work was done by means of computers. The recording was done by our technical staff members Ms. Helga Ballmann, Ms. Mona El-Choura, Ms. Monika Kohl, Ms. Sylvia Matyssek. Ms. Karin Burkhardt, Ms. Susanne Schlotelburg, and Mr. Stefan Wagner supported our task by careful proofreading. It is a pleasure to thank them all for their encouragement. Heidelberg, September 1985 The Editors Contents Introduction . . . . . . . . . . . .
Download or read book The 3 D Heliosphere at Solar Maximum written by R.G. Marsden and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book The Heliosphere at Solar Minimum and Beyond written by COSPAR. Scientific Commission D. D0.2 Symposium and published by Elsevier Science & Technology. This book was released on 1997 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Paperback. The Heliosphere is the large volume of space dominated by the expanding solar atmosphere. Even the most distant spacecraft, now at more than sixty Astronomical Units (1 Astronomical Unit = 150 million kilometers) from the sun, have yet to encounter the boundary between the Heliosphere and interstellar space. This publication contains 30 papers, reporting observations made throughout the Heliosphere and presenting theories to explain these observations. The results of the Ulysses spacecraft mission, the first to explore the Heliosphere over the solar poles, are summarised. Modulation of the galactic cosmic radiation and energetic solar particles by heliospheric structures is discussed. New results on the anomalous component of cosmic radiation are given, and predictions are made as to where the boundary of the Heliosphere may be found.
Download or read book Structure and Dynamics of the Three dimensional Heliosphere written by Ming Zhang and published by . This book was released on 2008 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Outer Heliosphere written by Klaus Scherer and published by . This book was released on 2000 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cosmic Radiation written by COSPAR. Scientific Assembly and published by Pergamon. This book was released on 1997 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication brings together two groups of papers under two headings. The first group of papers are under the heading 'Energetic Spectra and Charge Composition of Galactic Cosmic Rays above 10 eV: Implications for the Origin and Acceleration limit of Galactic Cosmic Rays'. This session contains 4 papers on the 'knee' region of the cosmic ray spectrum near 1PeV energies. The session has some discussion of proposed instruments to investigate this region and other theoretical papers which investigate the generation and transport of these particles in our galaxy. The second group of papers are under the heading 'Cosmic Ray Composition Studies at Solar Minimum'. This session contains 18 papers providing results relating to experiments flown during the latest solar minimum. Areas covered include new Observations of Galactic Cosmic Rays (GCRs), new Ulysses measurements of GCR spectra outside the ecliptic plane, several theoretical studies, new observations of Anomalous Cosmic Ray (ACR) from two spacecraft, and description of an alternative approach to simulation of ACR transport in the heliosphere.
Download or read book 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 written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Physics Briefs written by and published by . This book was released on 1988 with total page 882 pages. Available in PDF, EPUB and Kindle. Book excerpt:
