Astronomy and Astrophysics Space Science in the Twenty-First Century -- Imperatives for the Decades 1995 to 2015 (1988) / Chapter Skim
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1. Introduction and Summary
1. Introduction and Summary
Pages 1-7
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From page 1... ...
Discovery of the underlying relationship between the large-scare properties of the universe and the microscopic laws of physics would be a new triumph of human thought, comparable in impact with the Newtonian synthesis or Einstein's theory of general relativity. The extraordinary richness of astronomical phenomena ensures that the age of discovery is not behind us and that "there are more things in Heaven and Earth, Horatio, than are dreamt of in your philosophy." Even though the details of astronomical knowledge change as new discoveries are made, there are three major themes that have guided the astronomer's quest for knowledge for several decades.
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From page 2... ...
The experience of the past 30 years clearly shows that observations across the electromagnetic spectrum from gamma rays to radio waves, as well as detection of cosmic-ray particles, are required to study the enormous variety of physical conditions found in the universe. The use of space observations has already revealed the existence of matter in previously unknown forms.
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From page 3... ...
They have even let us "hear" the ubiquitous radio background radiation reaching us from the most distant portions of the universe ever observed attesting to an intensely hot, explosive origin of the cosmos. When we examine the history of technological advances for monitoring all wavelengths of radiation, we see a rapidly expanding observational capability in the post-WorId War II era.
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From page 4... ...
X-ray telescopes, in contrast, register x-ray pulses emitted by compact binary stars, while radio telescopes present us with a map showing the distribution of hydrogen clouds pervading the interstellar spaces. Finally, a gamma-ray telescope scanning the Milky Way would observe occasional powerful bursts of gamma rays from unpredictable directions at intervals of a few weeks.
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From page 5... ...
The importance of this temperature drop is that the nature of physical interactions depends strongly on the energy of the interacting radiation or matter. A change in particle energy by a factor of 10 can lead to dramatic changes in the types of particles that the universe contains, in the interactions that these particles exhibit, and in the laws of physics that such matter obeys.
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From page 6... ...
But recent infrared observations by the Infrared Astronomical Satellite (IRAS a joint U.S.-Dutch-British project) and from ground-based observatories have provided evidence of some stars surrounded by disks of dust and of others with companions not much more massive than the planet Jupiter.
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From page 7... ...
Their brightness can vary suddenly from hour to hour, indicating an enormously compact central energy supply that powers these enigmatic sources. Both optical and infrared interferometers of the future could achieve angular resolutions measured in microarcseconds a resolution that would allow someone on Earth to distinguish the features of a man standing on the Moon.
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