Observational cosmology within the ESA science programme

1990 ◽  
Vol 13 (1) ◽  
pp. 1-17 ◽  
Author(s):  
R. M. Bonnet
Keyword(s):  
Observational Cosmology ◽  
Science Programme

Astronomy on Ice

1986 ◽  
Vol 6 (4) ◽  
pp. 403-415 ◽  
Author(s):  
Martin A. Pomerantz
Keyword(s):  
Gamma Ray ◽  
Far Infrared ◽  
The United States ◽  
High Energy ◽  
Observational Cosmology ◽  
Significant Information ◽  
Infrared Measurements ◽  
Energy Gamma ◽  
Low Humidity ◽  
Scientific Station

AbstractThe geographic South Pole, where the United States maintains a year-round scientific station, affords a number of unique advantages for certain types of astronomical observations. These include: continuous viewing and constant declination of ail objects in the southern celestial hemisphere, exceedingly low humidity, extended periods of coronal seeing, high altitude, and uniform terrain. The areas of research that have already benefited immensely from thèse extraordinary features are helioseismology and submillimeter astronomy. Unparalleled observations of global solar oscillations have already yielded significant information about the structure and dynamics of the Sun’s interior. Far infrared measurements of various galactic and extra-galactic regions have attained an unprecedented level of sensitivity, limited for the first time only by the noise inherent in the detector. In addition to further helioseismological observations, currently planned future activities include observational cosmology and ultra high energy gamma ray astronomy.

Europe's Path To Mars: The European Space Agency's Mars Express Mission

2011 ◽  
Vol 41 (2) ◽  
pp. 123-178 ◽  
Author(s):  
Arturo Russo
Keyword(s):  
Selection Process ◽  
European Space Agency ◽  
Management Approach ◽  
Mars Exploration ◽  
Mars Express ◽  
The Public ◽  
Science Programme ◽  
Space Agency ◽  
History Of

Mars Express is the first planetary mission accomplished by the European Space Agency (ESA). Launched in early June 2003, the spacecraft entered Mars's orbit on Christmas day of that year, demonstrating the new European commitment to planetary exploration. Following a failed attempt in the mid-1980s, two valid proposals for a European mission to Mars were submitted to ESA's decision-making bodies in the early 1990s, in step with renewed international interest in Mars exploration. Both were rejected, however, in the competitive selection process for the agency's Science Programme. Eventually, the Mars Express proposal emerged during a severe budgetary crisis in the mid-1990s as an exemplar of a “flexible mission” that could reduce project costs and development time. Its successful maneuvering through financial difficulties and conflicting scientific interests was due to the new management approach as well as to the public appeal of Mars exploration. In addition to providing a case study in the functioning of the ESA's Science Programme, the story of Mars Express discussed in this paper provides a case study in the functioning of the European Space Agency's Science Programme and suggests some general considerations on the peculiar position of space research in the general field of the history of science and technology.

Origin and evolution of the large-scale structure of the universe

1990 ◽  
Vol 68 (9) ◽  
pp. 799-807
Author(s):  
Joseph Silk
Keyword(s):  
Large Scale ◽  
Background Radiation ◽  
Building Blocks ◽  
Large Scale Structure ◽  
Big Bang ◽  
Scale Structure ◽  
Observational Cosmology ◽  
Spontaneous Breaking ◽  
Fluctuation Spectrum ◽  
The Universe

Ever since the epoch of the spontaneous breaking of grand unification symmetry between the nuclear and electromagnetic interactions, the universe has expanded under the imprint of a spectrum of density fluctuations that is generally considered to have originated in this phase transition. I will discuss various possibilities for the form of the primordial fluctuation spectrum, spanning the range of adiabatic fluctuations, isocurvature fluctuations, and cosmic strings. Growth of the seed fluctuations by gravitational instability generates the formation of large-scale structures, from the scale of galaxies to that of clusters and superclusters of galaxies. There are three areas of confrontation with observational cosmology that will be reviewed. The large-scale distribution of the galaxies, including the apparent voids, sheets and filaments, and the coherent peculiar velocity field on scales of several tens of megaparsecs, probe the primordial fluctuation spectrum on scales that are only mildly nonlinear. Even larger scales are probed by study of the anisotropy of the cosmic microwave background radiation, which provides a direct glimpse of the primordial fluctuations that existed about 106 years or so after the initial big bang singularity. Galaxy formation is the process by which the building blocks of the universe have formed, involving a complex interaction between hydrodynamical and dynamical processes in a collapsing gas cloud. Both by detection of forming galaxies in the most remote regions of the universe and by study of the fundamental morphological characteristics of galaxies, which provide a fossilized memory of their past, can one relate the origin of galaxies to the same primordial fluctuation spectrum that gave rise' to the large-scale structure of the universe.

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