Space School Neptune Découverte d'une planète de diamant Imaginez un diamant qui fasse cinq fois la taille de la Terre... Ce n'est pas un rêve de joaillier, mais la trouvaille bien réelle d'une équipe de chercheurs, qui a découvert une nouvelle planète qui n'est en fait qu'un gigantesque diamant. Le carbone présent sur la planète en orbite autour d'une étoile à neutrons, aurait crystallisé pour se transformer en diamant, révèlent les chercheurs dans leur étude, parue dans le journal scientifique Science. Et ce n'est pas la seule originalité de cette planète, qui fait donc environ cinq fois la taille de la Terre, rapporte le site Space. L'étoile à neutrons autour de laquelle elle orbite est une pulsar milliseconde, un type d'étoile qui a généralement un compagnon, une autre étoile, en train de mourir, qu'on appelle une naine blanche. Les chercheurs pensent que la planète de diamant était ce compagnon, cette naine blanche. Le chercheur qui dirige l'équipe explique que leur découverte est une déduction logique: publicité Devenez fan sur
Scientist creates lifelike cells out of metal Scientists trying to create artificial life generally work under the assumption that life must be carbon-based, but what if a living thing could be made from another element? One British researcher may have proven that theory, potentially rewriting the book of life. Lee Cronin of the University of Glasgow has created lifelike cells from metal — a feat few believed feasible. Even more remarkable, Cronin has hinted that the metal-based cells may be replicating themselves and evolving. "I am 100 percent positive that we can get evolution to work outside organic biology," he said. The high-functioning "cells" that Cronin has built are constructed from large polyoxometalates derived from a range of metal atoms, like tungsten. The metallic bubbles are certainly cell-like, but are they actually alive? Cronin's team has also created bubbles inside of bubbles, which opens the door to the possibility of developing specialized "organelles." The early results have been encouraging.
The Life And Death Of Stars Introduction When I heard the learned astronomer, When the proofs, the figures were ranged in columns before me, When I was shown the charts and diagrams, to add, divide, and measure them, When I sitting heard the astronomer where he lectured with much applause in the lecture-room, How soon unaccountable I became tired and sick, Till rising and gliding out I wandered off by myself In the mystical moist night air, and from time to time Looked up in perfect silence at the stars. Walt Whitman Mr. I have been teaching physics and astronomy at Northwestern University since 1989 (thus I qualify as the "learned astronomer" in the poem), and I felt that surely there was room on the web for a few pages situated firmly between these extremes. Throughout this site, I have adhered to the principle that there is a big difference between simplified and simple. So much for the introduction; let's start talking about astrophysics! David Taylor Evanston, IL June, 2012 d-taylor2@northwestern.edu
Space School - Strange Things Les jeux freinent le déclin mental des gens âgés Si les jeux vidéo sont parfois décrits comme mauvais pour les enfants, ils seraient au contraire bons pour les plus de 50 ans, mobilisant et améliorant leurs facultés cognitives, affirme une étude américaine publiée cette semaine. Les centaines de personnes de plus de 50 ans observées par des chercheurs de l'Université de l'Iowa ont montré des signes d'amélioration de leurs capacités cognitives et de recul de plusieurs années du déclin lié à la vieillesse. Il s'agit de la dernière d'une série d'études qui visent à comprendre pourquoi, en vieillissant, on perd ces fonctions majeures du cerveau qui assurent le fonctionnement de la mémoire, de l'attention, de la perception et de la résolution de problèmes. Dans ce cas, 681 personnes en bonne santé ont été réparties en quatre groupes témoins, à l'intérieur desquels ont également été séparés les 50-64 ans et les plus de 65 ans. Le but est de monter en niveaux de difficulté.
Evidence for the Big Bang | National Schools' Observatory Astronomers think that the Universe started with the Big Bang. As with all science, this is based on evidence; so what is the evidence for the Big Bang theory? The spiral galaxy - M51 1. Redshift of Galaxies The redshift of distant galaxies means that the Universe is probably expanding. Cosmic Microwave Background 2. Very early in its history, the whole Universe was very hot. This is the Cosmic Microwave Background which has been accurately measured by orbiting detectors, and is very good evidence that the Big Bang theory is correct. The Sun is a fairly new star 3. As the Universe expanded and cooled down, some of the elements that we see today were created. You cannot look in new stars, like the Sun, for this evidence, because they contain elements that were created in previous generations of stars. Galaxies of long ago 4. The main alternative to the Big Bang theory of the Universe is called the Steady State theory.
Space School The Sun 300 millions d'ans UFO dents de roues trouvait dans la ville russe de Vladivostok | Observations OVNI hotspot During a cold winter evening a resident of Vladivostok found a rail-shaped metal detail which was pressed in one of the pieces of coal that the man used to heat his home. Mesmerized by his discovery, the responsible citizen decided to seek help from the scientists of Primorye region. After the metal object was studied by the leading experts the man was shocked to learn about the assumed age of his discovery. The metal detail was supposedly 300 million years old and yet the scientists suggest that it was not created by nature but was rather manufactured by someone. The question of who might have made an aluminum gear in the dawn of time remains unanswered. Nowadays, finding a strange artifact in coal is a relatively frequent occurrence. The metal detail which was found by Vladivostok resident is yet another discovery which perplexed the scientists. Another question that interests Russian scientists is whether the aluminum alloy is of Earthly origin.
Space School Pluto Miniature Chameleons Discovered—Fit on Match Tip Photograph courtesy Frank Glaw Match-tip tiny, Brookesia micra (juvenile pictured) is the smallest of four new chameleon species found on the African island country of Madagascar. With an average adult length of just over an inch (2.9 centimeters) from snout to tail, B. micra is among the tiniest reptiles in the world. (Related: "Record-Breaking Chameleons Live Only a Few Months.") Scientists think the diminutive new chameleon species might represent extreme cases of island dwarfism, whereby organisms shrink in size due to limited resources on islands. "The extreme miniaturization of these dwarf reptiles might be accompanied by numerous specializations of the body plan, and this constitutes a promising field for future research," study leader Frank Glaw of Germany's Zoological State Collection said in a statement.
Space School Uranus