In the Shadow of the Moon: America, Russia, and the Hidden History of the Space Race by Amy Cherrix

The core dynamos of Mars and the Moon have distinctly different histories. Mars had no core dynamo at the end of accretion. It took ∼100 Myr for the core to create a strong dynamo that magnetized the martian crust. Giant impacts during 4.2–4.0 Ga crippled the core dynamo intermittently until a thick stagnant lithosphere developed on the surface and reduced the heat flux at the core–mantle boundary, killing the dynamo at ∼3.8 Ga. On the other hand, the Moon had a strong core dynamo at the end of accretion that lasted ∼100 Myr and magnetized its primordial crust. Either precession of the core or thermochemical convection in the mantle or chemical convection in the core created a strong core dynamo that magnetized the sources of the isolated magnetic anomalies in later times. Mars and the Moon indicate dynamo reversals and true polar wander. The polar wander of the Moon is easier to explain compared to that of Mars. It was initiated by the mass deficiency at South Pole Aitken basin, which moved the basin southward by ∼68° relative to the dipole axis of the core field. The formation of mascon maria at later times introduced positive mass anomalies at the surface, forcing the Moon to make an additional ∼52° degree polar wander. Interaction of multiple impact shock waves with the dynamo, the abrupt angular momentum transfer to the mantle by the impactors, and the global overturn of the core after each impact were probably the factors causing the dynamo reversal.

Download Full-text

The Mausoleum of Youth: Between Experience and Nihilism in Benjamin's Berlin Childhood

Paragraph ◽

10.3366/e0264833409000662 ◽

2009 ◽

Vol 32 (3) ◽

pp. 313-330 ◽

Cited By ~ 1

Author(s):

Michael W. Jennings

Keyword(s):

Human Experience ◽

The Moon ◽

History Of Photography ◽

Work Of Art ◽

Modern Media ◽

Siegfried Kracauer ◽

History Of ◽

The Relationship

Key sections of Walter Benjamin's montage-text Berlin Childhood around 1900 figure the relationship between human experience and modern media, with the sections that frame the text, ‘Loggias’ and ‘The Moon’, structured around metaphors of photography. Drawing on the work of Siegfried Kracauer, and especially his seminal essay ‘Photography’, Benjamin develops, in the course of his book, a theory of photography's relationship to experience that runs counter to the better-known theories developed in such essays as ‘Little History of Photography’ and ‘The Work of Art in the Age of its Technological Reproducibility’, theories that are part of the broad currents of technological utopianism and, as such, emphasize photography's transformative potentials. In the Berlin Childhood, Benjamin instead emphasizes photography's role in the mortification and annihilation of meaningful human experience. Photography emerges here as the mausoleum of youth and hope.

Download Full-text

INTRODUCTION

Ancient Mesoamerica ◽

10.1017/s0956536107000156 ◽

2007 ◽

Vol 18 (1) ◽

pp. 107-108 ◽

Cited By ~ 1

Author(s):

William R. Fowler

Keyword(s):

Urban Landscape ◽

Special Section ◽

Third Century ◽

The Sun ◽

Urban Archaeology ◽

The Moon ◽

History Of ◽

The Temple

This is the twenty-fifth Special Section published in Ancient Mesoamerica, and therefore it represents something of a milestone in the history of the journal. The goal has been to present in each special section a collection of related papers from a single project or region or on a selected topic to provide readers a tightly integrated summary of current research and interpretations. Certainly one of the most compelling and provocative special sections we have published was “Urban Archaeology at Teotihuacan” which appeared in vol. 2, no. 1 (1991). This collection of papers featured two stunning articles on the Feathered Serpent Pyramid, then often referred to as the Temple of Quetzalcoatl. Constructed in the early third century A.D., the Feathered Serpent Pyramid, along with the Sun Pyramid and the Moon Pyramid, was one of the three most powerful monuments in the sacred urban landscape of Teotihuacan. Rubén Cabrera Castro, Saburo Sugiyama, and George L. Cowgill (1991) reported on excavations in the 1980s of the Feathered Serpent Pyramid and the investigation of more than 137 sacrificial burials, including more than 70 males identified as soldiers because of associated offerings, discovered at the base of and underneath the pyramid. In the second article, Alfredo López Austin, Leonardo López Luján, and Saburo Sugiyama (1991) presented their brilliant iconographic analysis of the sculptural facades of the Feathered Serpent Pyramid, arguing that the monumental structure was dedicated to the myth of the origin of time and calendric succession, a tangible cosmogonic proclamation that Teotihuacan was “the place where time began.”

Download Full-text

History of the Crust of the Moon

The Moon's Near Side Megabasin and Far Side Bulge - SpringerBriefs in Astronomy ◽

10.1007/978-1-4614-6949-0_9 ◽

2013 ◽

pp. 97-110

Author(s):

Charles J. Byrne

Keyword(s):

The Moon ◽

History Of

Download Full-text

The Next Space Patrons

The Long Space Age ◽

10.12987/yale/9780300219326.003.0006 ◽

2017 ◽

Author(s):

Alexander MacDonald

Keyword(s):

Solar System ◽

Political History ◽

Space Exploration ◽

Development Program ◽

The Political ◽

Early American ◽

Long Run ◽

Space Race ◽

System P ◽

History Of

Mankind will not remain forever confined to the Earth. In pursuit of light and space it will, timidly at first, probe the limits of the atmosphere and later extend its control to the entire solar system. —Konstantin Tsiolkovsky, Letter to B. N. Vorobyev, 1911 What do we learn from this long-run perspective on American space exploration? How does it change our understanding of the history of spaceflight? How does it change our understanding of the present? This book has provided an economic perspective on two centuries of history, with examinations of early American observatories, the rocket development program of Robert Goddard, and the political history of the space race. Although the subjects covered have been wide-ranging, together they present a new view of American space history, one that challenges the dominant narrative of space exploration as an inherently governmental activity. From them a new narrative emerges, that of the Long Space Age, a narrative that in the ...

Download Full-text