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Books > Science & Mathematics > Astronomy, space & time > General
This book on space geodesy presents pioneering geometrical
approaches in the modelling of satellite orbits and gravity field
of the Earth, based on the gravity field missions CHAMP, GRACE and
GOCE in the LEO orbit. Geometrical approach is also extended to
precise positioning in space using multi-GNSS constellations and
space geodesy techniques in the realization of the terrestrial and
celestial reference frame of the Earth. This book addresses major
new developments that were taking place in space geodesy in the
last decade, namely the availability of GPS receivers onboard LEO
satellites, the multitude of the new GNSS satellite navigation
systems, the huge improvement in the accuracy of satellite clocks
and the revolution in the determination of the Earth's gravity
field with dedicated satellite missions.
Robert Grosseteste (1168/75-1253), Bishop of Lincoln from
1235-1253, is widely recognized as one of the key intellectual
figures of medieval England and as a trailblazer in the history of
scientific methodology. Few of his numerous philosophical and
scientific writings circulated as widely as the Compotus, a
treatise on time reckoning and calendrical astronomy apparently
written during a period of study in Paris in the 1220s. Besides its
strong and long-lasting influence on later writers, Grossteste's
Compotus is particularly noteworthy for its innovatory approach to
the theory and practice of the ecclesiastical calendar-a subject of
essential importance to the life of the Latin Church. Confronting
traditional computistical doctrines with the lessons learned from
Graeco-Arabic astronomy, Grosseteste offered his readers a critical
and reform-oriented take on the discipline, in which he proposed a
specific version of the Islamic lunar as a substitute for the
failing nineteen-year cycle the Church still employed to calculate
the date of Easter. This new critical edition of Grosseteste's
Compotus contains the Latin text with an en-face English
translation. It is flanked by an extensive introduction and chapter
commentary, which will provide valuable new insights into the
text's purpose and disciplinary background, its date and
biographical context, its sources, as well as its reception in
later centuries.
A contemporary of Galileo and a forerunner of Isaac Newton,
Johannes Kepler (1571-1630) was a pioneering German scientist and a
pivotal figure in the history of astronomy. This colorful,
well-researched biography brings the man and his scientific
discoveries to life, showing how his contributions were every bit
as important as those of Copernicus, Galileo, and Newton. It was
Kepler who first advocated the completely new concept of a physical
force emanating from the sun that controls the motion of the
planets--today we call this gravity and take it for granted. He
also established that the orbits of the planets were elliptical in
shape and not circular. And his three laws of planetary motion are
still used by contemporary astronomers and space scientists. The
author focuses not just on these and other momentous breakthroughs
but also on Kepler's arduous life, punctuated by frequent tragedy
and hardships. His first wife died young, and eight of the twelve
children he fathered succumbed to disease in infancy or childhood.
He was frequently caught up in the religious persecutions of the
day. His mother narrowly escaped death when she was accused of
being a witch. Intermingling historical and personal details of
Kepler's life with lucid explanations of his scientific research,
this book presents a sympathetic portrait of the man and
underscores the critical importance of Kepler's discoveries in the
history of astronomy.
A contemporary of Galileo and a forerunner of Isaac Newton,
Johannes Kepler (1571-1630) was a pioneering German scientist and a
pivotal figure in the history of astronomy. This colorful,
well-researched biography brings the man and his scientific
discoveries to life, showing how his contributions were every bit
as important as those of Copernicus, Galileo, and Newton.It was
Kepler who first advocated the completely new concept of a physical
force emanating from the sun that controls the motion of the
planets--today we call this gravity and take it for granted. He
also established that the orbits of the planets were elliptical in
shape and not circular. And his three laws of planetary motion are
still used by contemporary astronomers and space scientists.The
author focuses not just on these and other momentous breakthroughs
but also on Kepler's arduous life, punctuated by frequent tragedy
and hardships. His first wife died young, and eight of the twelve
children he fathered succumbed to disease in infancy or childhood.
He was frequently caught up in the religious persecutions of the
day. His mother narrowly escaped death when she was accused of
being a witch.Intermingling historical and personal details of
Kepler's life with lucid explanations of his scientific research,
this book presents a sympathetic portrait of the man and
underscores the critical importance of Kepler's discoveries in the
history of astronomy.
Pulsar timing is a promising method for detecting gravitational
waves in the nano-Hertz band. In his prize winning Ph.D. thesis
Rutger van Haasteren deals with how one takes thousands of
seemingly random timing residuals which are measured by pulsar
observers, and extracts information about the presence and
character of the gravitational waves in the nano-Hertz band that
are washing over our Galaxy. The author presents a sophisticated
mathematical algorithm that deals with this issue. His algorithm is
probably the most well-developed of those that are currently in use
in the Pulsar Timing Array community. In chapter 3, the
gravitational-wave memory effect is described. This is one of the
first descriptions of this interesting effect in relation with
pulsar timing, which may become observable in future Pulsar Timing
Array projects. The last part of the work is dedicated to an effort
to combine the European pulsar timing data sets in order to search
for gravitational waves. This study has placed the most stringent
limit to date on the intensity of gravitational waves that are
produced by pairs of supermassive black holes dancing around each
other in distant galaxies, as well as those that may be produced by
vibrating cosmic strings. Rutger van Haasteren has won the 2011
GWIC Thesis Prize of the Gravitational Wave International Community
for his innovative work in various directions of the search for
gravitational waves by pulsar timing. The work is presented in this
Ph.D. thesis.
This book offers review chapters written by invited speakers of the
3rd Session of the Sant Cugat Forum on Astrophysics - Gravitational
Waves Astrophysics. All chapters have been peer reviewed. The book
goes beyond normal conference proceedings in that it provides a
wide panorama of the astrophysics of gravitational waves and serves
as a reference work for researchers in the field.
In this thesis, ultimate sensitive measurement for weak force
imposed on a suspended mirror is performed with the help of a laser
and an optical cavity for the development of gravitational-wave
detectors. According to the Heisenberg uncertainty principle, such
measurements are subject to a fundamental noise called quantum
noise, which arises from the quantum nature of a probe (light) and
a measured object (mirror). One of the sources of quantum noise is
the quantum back-action, which arises from the vacuum fluctuation
of the light. It sways the mirror via the momentum transferred to
the mirror upon its reflection for the measurement. The author
discusses a fundamental trade-off between sensitivity and stability
in the macroscopic system, and suggests using a triangular cavity
that can avoid this trade-off. The development of an optical
triangular cavity is described and its characterization of the
optomechanical effect in the triangular cavity is demonstrated. As
a result, for the first time in the world the quantum back-action
imposed on the 5-mg suspended mirror is significantly evaluated.
This work contributes to overcoming the standard quantum limit in
the future.
This thesis describes the essential features of Moon-plasma
interactions with a particular emphasis on the Earth's magnetotail
plasma regime from both observational and theoretical standpoints.
The Moon lacks a dense atmosphere as well as a strong intrinsic
magnetic field. As a result, its interactions with the ambient
plasma are drastically different from solar-wind interactions with
magnetized planets such as Earth. The Moon encounters a wide range
of plasma regime from the relatively dense, cold, supersonic
solar-wind plasma to the low-density, hot, subsonic plasma in the
geomagnetic tail. In this book, the author presents a series of new
observations from recent lunar missions (i.e., Kaguya, ARTEMIS, and
Chandrayaan-1), demonstrating the importance of the electron
gyro-scale dynamics, plasma of lunar origin, and hot plasma
interactions with lunar magnetic anomalies. The similarity and
difference between the Moon-plasma interactions in the geomagnetic
tail and those in the solar wind are discussed throughout the
thesis. The basic knowledge presented in this book can be applied
to plasma interactions with airless bodies throughout the solar
system and beyond.
This thesis develops new and powerful methods for identifying
planetary signals in the presence of "noise" generated by stellar
activity, and explores the physical origin of stellar intrinsic
variability, using unique observations of the Sun seen as a star.
In particular, it establishes that the intrinsic stellar
radial-velocity variations mainly arise from suppression of
photospheric convection by magnetic fields. With the advent of
powerful telescopes and instruments we are now on the verge of
discovering real Earth twins in orbit around other stars. The
intrinsic variability of the host stars themselves, however,
currently remains the main obstacle to determining the masses of
such small planets. The methods developed here combine
Gaussian-process regression for modeling the correlated signals
arising from evolving active regions on a rotating star, and
Bayesian model selection methods for distinguishing genuine
planetary signals from false positives produced by stellar magnetic
activity. The findings of this thesis represent a significant step
towards determining the masses of potentially habitable planets
orbiting Sun-like stars.
Winner of the 2021 Donald E. Osterbrock Book Prize for Historical
Astronomy In Decoding the Stars, Ileana Chinnici offers an account
of the life of the Jesuit scientist Angelo Secchi (1818-1878). In
addition to providing an invaluable account of Secchi's life and
work-something that has been sorely lacking in the English-language
scholarship-this biography will be especially stimulating for those
interested in the evolution of astrophysics as a discipline from
the nineteenth century onward. Despite his eclecticism, reminiscent
of the natural philosophers of the seventeenth and eighteenth
centuries, Secchi was in many ways a very modern scientist: open to
innovation and cooperation, and a promoter of popularization and
citizen science. Secchi also appears fully inserted in the cultural
context of his time: he participated in philosophical and
scientific debates, spread new theories and ideas, but also
suffered the consequences of political events that marked those
years and impacted on his life and activities.
This book presents the proceedings of the 2nd Karl Schwarzschild
Meeting on Gravitational Physics, focused on the general theme of
black holes, gravity and information.Specialists in the field of
black hole physics and rising young researchers present the latest
findings on the broad topic of black holes, gravity, and
information, highlighting its applications to astrophysics,
cosmology, particle physics, and strongly correlated systems.
In a series of illuminating lectures, Joseph A. Seiss presents a
clear picture of astronomical occurrences and inspirations to be
found in the Biblical New Testament and Gospels. A superbly
insightful Bible commentary, this book contains seventeen lectures,
each of which focuses upon a specific astronomical occurrence in
the New Testament. Events which draw specific influence from the
constellations of the stars are charted, with each star sign
identified as important to separate events depicted in the
scriptures of the gospels. The nativity of Jesus Christ, wherein
the Star of Bethlehem appears to the three wise men, is perhaps the
most obvious incident of the astronomical. However, Seiss
demonstrates that the stars above are richly significant and play a
role in many of the most famous tales of the Bible. For example,
when Seiss recounts the story of St. Peter's fishing, he compares
the sign of Pisces, which was already widely known in the Biblical
era.
The zodiac was first clearly defined by the Babylonians some 2500
years ago, but until recently the basis of this original definition
remained unknown. This zodiac of the Babylonians, known as the
sidereal zodiac because it is specified in direct relation to the
stars (Latin sideris, 'starry'), was used for centuries throughout
the ancient world, all the way to India, and must be distinguished
from the tropical zodiac in widespread use by astrologers in the
West today, which was introduced only in the middle of the second
century A.D. by the Greek astronomer Claudius Ptolemy. Such was
Ptolemy's influence, however, that the tropical zodiac gained
prominence and, except for its survival (in a variant form) in
India, knowledge of the sidereal zodiac was lost. In this thrilling
study of the history of the zodiac, first submitted in 2004 as his
Ph.D. thesis, Robert Powell rescues the the sidereal zodiac from
the dusts of time, tracing it back to the Babylonians in the
sixth/fifth centuries B.C. The implications of this discovery-among
them the restitution of the sideral zodiac to its rightful place at
the heart of astrology-are immense, they key point being that the
signs of the sidereal zodiac, each thirty degrees long, coincide
closely with the twelve astronomical constellations of the same
name, whereas the signs of the tropical zodiac, since they are
defined in relation to the vernal point, now have no direct
relationship to the corresponding zodiacal constellations, owing to
the precession of the equinoxes.This revolutionary history of the
zodiac includes chapters on the Egyptian decans and the Hindu
nakshatras, showing how these sidereal divisions, which originated
in Egypt and India, are related to the original Babylonian zodiac.
It also sheds light on the controversy surrounding the 'zodiac
question' (tropical vs. sidereal), illuminating the history of the
tropical zodiac-showing that originally it was not a zodiac at all,
but a calendar for describing the course of the seasons This book,
the fruit of thirty years of research, is intended not only for
scholars but for general readers as well, and offers the clearest
and most comprehensive study of the history of the zodiac yet
published.
A physicist and an inventor, Jules Janssen (1824-1907) devoted his
life to astronomical research. He spent many years traveling around
the world to observe total Solar eclipses, demonstrating that a new
era of science had just come thanks to the use of both spectroscopy
and photography, and persuading the French Government of the
necessity of founding a new observatory near Paris. He became its
director in 1875. There, at Meudon, he began routine photographic
recordings of the Sun surface and had a big refractor and a big
reflector built. Meanwhile, he also succeeded in building an
Observatory at the summit of Mont-Blanc. The story of this untiring
and stubborn globe-trotter is enriched by extracts of the
unpublished correspondence with his wife. One can thus understand
why Henriette often complained of the solitude in which she was
left by her peripatetic husband: "There are men who leave their
wives for mistresses; you do it for journeys!" ... Basking in the
glow of his success, Janssen was able to undertake the construction
of the great astrophysical observatory of which he had dreamed. It
was at Meudon that he had it built.
The large telescope at Meudon has become legendary. When it was
conceived, after 1870, astronomy as a whole was limited to visual
observation. Knowledge of the sky was limited to what one could
see, assisted only by optical means. The large telescopes produced
at this time produced larger images, permitting close-up views: the
Meudon telescope was able to accomplish this perfectly. At Meudon,
which became the Mecca of visual observation, the major planets
were examined in a way that no other telescope had previously been
able to. The telescope monitored the state of their atmospheres and
mapped the appearance of their surfaces. Through the telescope, one
could obtain photographs showing the nuclei of comets, revealing
their very small size, and by using an eyepiece one could measure
the separation of double stars. With a marvellous little
instrument, the polarimeter, the nature of clouds in planetary
atmospheres has been determined, and the type of surface material
identified. Many more results were obtained, while photography,
universally adopted, revolutionized other knowledge about the
world. The sensitive emulsion, combined with large aperture
reflecting telescopes, revealed the deepness and richness of the
cosmos. The vast telescope of Meudon, which was the largest
refracting telescope in Europe, became a legendary instrument and
was symbolic of a new way to practice astronomy. Audouin Dollfus, a
renowned astronomer, describes the great years of the Meudon
telescope. He gives us the entire story of this instrument, from
the birth of the concept that drove Jules Janssen at the end of the
nineteenth century, to the idea that French astronomy could provide
an outstanding telescope which would approach the limits of
technical and industrial resources. The telescope remained
unchanged until 2006, when the first steps toward restoration and
public reopening were taken.
Nature is characterized by a number of physical laws and
fundamental dimensionless couplings. These determine the properties
of our physical universe, from the size of atoms, cells and
mountains to the ultimate fate of the universe as a whole. Yet it
is rather remarkable how little we know about them. The constancy
of physical laws is one of the cornerstones of the scientific
research method, but for fundamental couplings this is an
assumption with no other justification than a historical
assumption. There is no 'theory of constants' describing their role
in the underlying theories and how they relate to one another or
how many of them are truly fundamental. Studying the behaviour of
these quantities throughout the history of the universe is an
effective way to probe fundamental physics. This explains why the
ESA and ESO include varying fundamental constants among their key
science drivers for the next generation of facilities. This
symposium discussed the state-of-the-art in the field, as well as
the key developments anticipated for the coming years.
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