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9EU.1 le mouvement et les caractéristiques des corps astronomiqu

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Fandom powered by Wikia. Sulfur planet is a theoretical class of planet with surface covered in lakes or oceans of sulfuric acid with sulfuric acid clouds in the atmosphere.

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Kepler-52c (Iamidae), Kepler-47b (Mellona), Tau Ceti e (Aita), and KIC 5522786 b (Sreng) are speculated sulfur planets as of 2014. Venus has sulfuric acid clouds in the atmosphere, but Venus is not considered a sulfur planet because there is not quite enough sulfur on its surface. Instead, much of the surface is covered in solidified lava. Appearance Edit Viewed from space, sulfur planet would appear yellow, just like the element sulfur itself as shown in the image. Animations of tidally locked Earth. Timothy Merlis and Tapio Schneider, 2010 To explore climate dynamics of tidally locked Earth-like exoplanets and to illustrate how the climate would adjust if Earth abruptly entered a tidally locked state, we conducted simulations with the GFDL CM2.1 coupled climate model (Delworth et al. 2006).

Animations of tidally locked Earth

Starting from a typical January 1 initial condition in the present-day climate, we set the planetary rotation rate to 1/365th of the present value (so that 1 day is equal to 1 current Earth year). We fixed the insolation so that there is a perpetual subsolar point on the equator at 88°W (near the coast of Ecuador). The simulation was run for 50 years. This simulation with a comprehensive coupled climate model illustrates and expands upon the dynamics discussed in the context of an aquaplanet atmosphere-only model in Merlis and Schneider (2010). The surface temperature changes rapidly over land masses to day-side values of about 290 K and to night-side values of about 240 K. This Molecule Could've Created the Backbone of DNA and Helped to Kick-Start Life. In a new study out today, scientists may have taken another key step toward explaining how genetic materials—and life—may have first formed on the Earth.

This Molecule Could've Created the Backbone of DNA and Helped to Kick-Start Life

The molecule is question is called formamide. It's pretty simple; the molecular formula is NH2CHO. It's incredibly abundant in our universe, appearing in absurdly huge interstellar clouds, and is believed to be a vital component of almost all infantile, planet-forging star systems. And some researchers think formamide could have a key player in the origin of life. Last December, for example, a team of Czech researchers discovered that the energy you'd get form a comet or asteroid impact would be enough to instantaneously transform formamide into many of the molecular letters of our genetic alphabet. The Seven Wonders of TRAPPIST-1. Fandom powered by Wikia. Ammonia planet is an assumed class of planet with surface covered in lakes or oceans of ammonia with ammonia clouds in the atmosphere.

Fandom powered by Wikia

Appearance Edit Viewed from space, ammonia oceans would usually appear dark brown due to large amounts of alkaline earth metals dissolved in it. Speculative Evolution Wiki. Also see: Exotic life Despite its diversity, all life on Earth displays a remarkable similarity at biochemical level: all the main molecules used in organic processes are built on skeletons of carbon and hydrogen; ions and molecules are dissolved and transported in water-based fluids; most organism breathe oxygen to release energy from food.

Speculative Evolution Wiki

It's still a matter of debate if organic processes can be supported by different biochemical systems. If they can, though, and therefore much wider conditions are suitable to life, potential life-bearing planets become far more common, and their flora and fauna could be much more alien. Non-carbon basis of biochemistry Carbon is perhaps the most important element in our chemical makeup, to the point that organic molecules are defined by the presence of carbon atoms in their structure. Silicon The element most similar to carbon, being right under it in the periodic table, is silicon (Si). Other elements. Biochimies hypothétiques. Un article de Wikipédia, l'encyclopédie libre.

Biochimies hypothétiques

Les biochimies hypothétiques sont des suppositions sur les types de biochimies que pourrait revêtir une vie extraterrestre exotique selon des formes différant radicalement de celles connues sur Terre[1]. Elles comprennent les biochimies employant des éléments autres que le carbone pour construire les structures moléculaires primaires et/ou se produisant dans des solvants autres que l'eau. Les évocations de vie extraterrestre fondées sur ces biochimies « alternatives » sont communes dans la science-fiction. Exoplanet Exploration: Planets Beyond our Solar System: Interactives. Planet Temperature Calculator. Mass of your star The first step is to enter the MASS of the star that your planet is orbiting.

Planet Temperature Calculator

Our Sun has a "solar" mass of 1.0. Below 0.08 solar masses, a celestial object cannot initiate nuclear fusion and is not considered to be a star. Above 100 solar masses, the object is unstable, and so stars of such high masses probably do not form. The mass of your central star should be somewhere between 0.08 and 100 times the mass of our Sun. SK Curriculum. Pose des questions sur les caractéristiques des corps astronomiques et sur les rapports entre eux.

SK Curriculum

Observe et détermine la trajectoire des principaux corps visibles dans le ciel nocturne. Explique le mouvement apparent, y compris le mouvement rétrograde des corps célestes (p. ex. Soleil, lune, planètes, comètes et astéroïdes). Crée une représentation physique ou visuelle du mouvement apparent des corps célestes, y compris du mouvement rétrograde, vu de divers endroits dans notre système solaire. Copernic et galilee. Copernic et Galilée. La révolution copernicienne. Galilée et la révolution copernicienne. Ptolemaic Phases of Venus. Shows what Venus would look like through a telescope if Ptolemy's model was correct.

Ptolemaic Phases of Venus

Compare with the other Phases of Venus simulation. Running this animation on your computer... right-click to download ptolemaic.swf and ptolemaic.html to the same directory open the html file in a browser to run the animation Linking to this animation... copy and paste the code below into your webpage or blog: Phases of Venus. Shows what Venus looks like through a telescope as the planets go around in their orbits.

Phases of Venus

Compare with the Ptolemaic Phases of Venus simulation. Running this animation on your computer... right-click to download venusphases.swf and venusphases.html to the same directory open the html file in a browser to run the animation Linking to this animation... copy and paste the code below into your webpage or blog: Putting this animation on your website... upload venusphases.swf to the same directory as your webpage copy and paste the following code into your webpage: Retrograde Motion. My Solar System 2.04. Orbit Simulator. Saturne, Mars et Antarès s’alignent dans le ciel du soir. 17 000000000 fois notre soleil : nos astronomes trébuchent sur un trou noir massif. Gaz et poussières autour d’un trou noir. Si une partie de cette matière est attirée et sera, finalement, « avalée » par le trou noir, une autre est éjectée au loin, sous forme de ventsCrédit photo : NASA/M.Weiss Une équipe de scientifiques canadiens, allemands et américains se dit à la fois surprise et fascinée par sa découverte complètement inattendue d’un des plus grands trous noirs supermassifs découverts à ce jour.

Le trou noir, situé au centre de la galaxie NGC 1600 dans la constellation Eridanus, est de 17 milliards de fois la masse de notre soleil. Il est donc à peine plus petit que le plus grand trou noir jamais découvert à ce jour, qui est de 21 milliards de fois la masse du soleil. Grosse année pour les Perséides. Poussière de comète Les Perséides sont des poussières émises par la queue d'une comète appelée Swift-Tuttle, qui passe près de la Terre tous les 133 ans. Les poussières de sa queue rencontrent toutefois la Terre tous les mois d'août. Ces poussières brûlent en rentrant dans l'atmosphère, à une vitesse de 60 kilomètres par seconde. L'expansion de l'Univers plus rapide qu'on le pense? L'Univers est l'un des plus grands mystères soumis aux chercheurs. Entre matière noire, énergie sombre et trous noirs, de nombreuses questions restent en suspens.

Certains phénomènes sont toutefois prouvés. Cinq choses à savoir sur la nouvelle « neuvième planète » La publication, mercredi, d’une étude prédisant l’existence d’une planète massive encore inconnue a fait sensation. Il y a pourtant de quoi relativiser. Le Monde.fr | • Mis à jour le | Par Gary Dagorn.