Astronomie

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100,000 Stars.

Les Comètes

Les Astéroides. SKY-MAP.ORG. 100,000 Stars. Infinity Imagined. A Review of the Universe. Magnitude. Relativistic Cosmology. Back to main course page John D.

Relativistic Cosmology

Norton Department of History and Philosophy of Science University of Pittsburgh Einstein's Great Book of Universes The arrival of Einstein's general theory of relativity marked a rebirth of interest and work in cosmology, the study of the universe on the largest scale. Within Newtonian theory, cosmology had reduced essentially to one question: just how is matter distributed within an infinite, Euclidean space. What connected all these together was Einstein's gravitational field equations. Minkowski Spacetime Minkowski spacetime is the spacetime in which special relativity holds. This is the unsummed curvature. Einstein's equations tell us that this summed curvature equals the matter density. A Minkowski spacetime is still physically relevant to our spacetime, however.

"Blue marble" image from NASA Yet in any small patch--such as an area of land the size of a city--we can ignore the curvature and apply Euclidean geometry without appreciable error. 2x + 1 = 5 λ. An Atlas of The Universe. Star Size Comparison HD. Scale of the Universe. Astronomy & Space. Top 100 Astronomers You’ve Probably Never Heard Of. How many of the faces above do you recognise? For a long time, I’ve wanted to investigate the the “who’s who” of astronomy via the literature but haven’t had the means.

I’ve teamed up with Andy Casey who has written a neat ADS-python module to access the ADS publication database. It is still early days at the moment so we’ve mainly been brainstorming but we figured we should start with the basics: most cited astronomers. There will be more posts to follow as we have more ideas under construction. For this exercise I just needed the raw list of names and citation count. If you clone the initial script and simply add the following snippet, it will search Google images and download the first 3 images it finds. Then after using opencv to do facial recognition, one can extract the faces in the appropriate images. It must be said that though raw citation count is not necessarily and indicator of ‘the best astronomer’ it is one such measure the academic community uses to quantify “influence”. Kavli Institute for Particle Astrophysics and Cosmology. Cielo Sur. Enabling Kids to Build the World's Largest Telescope.

SETI Institute. SETI: The Search for Extraterrestrial Intelligence. National Aeronautics and Space Administration NASA History Office SETI: The Search for ExtraTerrestrial Intelligence Since the beginning of civilization, people have wondered if we are alone in the universe or whether there is intelligent life somewhere else.

SETI: The Search for Extraterrestrial Intelligence

In the late twentieth century, scientists converged upon the basic idea of scanning the sky and "listening" for non-random patterns of electromagnetic emissions such as radio or television waves in order to detect another possible civilization somewhere else in the universe. In late 1959 and early 1960, the modern SETI era began when Frank Drake conducted the first such SETI search at approximately the same time that Giuseppe Cocconi and Philip Morrison published a key journal article suggesting this approach. NASA joined in SETI efforts at a low-level in the late 1960s and early 1970s. We also have several related full-length books now on-line. SETI@home. Espace.

Le Système Solaire

Logiciels. Observatoires. Organisations. Telescopes. Astro... Forum d'astronomie de Planète Astronomie. Planète Astronomie. L'Astronomie.