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Mystérieux cratères en Sibérie : c'est peut-être encore plus grave que ce que l'on croyait. Par Francetv info Mis à jour le , publié le Le phénomène est aussi spectaculaire qu'inquiétant.

Mystérieux cratères en Sibérie : c'est peut-être encore plus grave que ce que l'on croyait

L'été dernier, un immense cratère a été repéré en Sibérie, dans la péninsule de Yamal, bordée par l'océan Arctique. Il s'avère que le phénomène n'est pas isolé. Le sol de Sibérie explose, libérant du méthane : une menace pour les habitants. Juillet 2014. Quelques jours plus tard, un autre trou est découvert, puis un troisième. Mais, lundi 23 février, un scientifique russe respecté, Vasily Bogoyavlensky, tire la sonnette d'alarme dans le Siberian Times (article en anglais). Les chercheurs russes dénombrent sept cratères (désignés comme entonnoirs) dans cette région arctique particulièrement inhospitalière. En réalité, "nous n'avons la localisation que de quatre d'entre eux. Et le chercheur pense que le phénomène pourrait encore s'amplifier avec le réchauffement climatique. Angry Scientist Finds Uneducated Internet Comment And Delivers Badass Response...

Kepler-186f. Orbital parameters relative to habitable zone[edit] Mass, density and composition[edit] The only physical property directly derivable from the observations (besides the orbital period) is the ratio of the radius of the planet to that of the central star, which follows from the amount of occultation of stellar light during a transit.

Kepler-186f

This ratio was measured to be 0.021.[1] This yields a planetary radius of 1.11±0.14 times that of Earth,[2][5] taking into account uncertainty in the star's diameter and the degree of occultation. Thus, the planet is about 11% larger in radius than Earth (between 4.5% smaller and 26.5% larger), giving a volume about 1.37 times that of Earth (between 0.87 and 2.03 times as large). There is a very wide range of possible masses that can be calculated by combining the radius with densities derived from the possible types of matter that planets can be made from; it could be a rocky terrestrial planet or a lower density ocean planet with a thick atmosphere. NASA's Kepler Discovers First Earth-Size Planet In The 'Habitable Zone' of Another Star.

The artist's concept depicts Kepler-186f , the first validated Earth-size planet to orbit a distant star in the habitable zone.

NASA's Kepler Discovers First Earth-Size Planet In The 'Habitable Zone' of Another Star

[Click link below for more.] Image Credit: NASA Ames/SETI Institute/JPL-Caltech The diagram compares the planets of our inner solar system to Kepler-186, a five-planet star system about 500 light-years from Earth in the constellation Cygnus. The five planets of Kepler-186 orbit an M dwarf, a star that is is half the size and mass of the sun. Using NASA's Kepler Space Telescope, astronomers have discovered the first Earth-size planet orbiting a star in the "habitable zone" -- the range of distance from a star where liquid water might pool on the surface of an orbiting planet. While planets have previously been found in the habitable zone, they are all at least 40 percent larger in size than Earth and understanding their makeup is challenging.

Although the size of Kepler-186f is known, its mass and composition are not. Watch a video about the discovery. Scientists Discover Another Earth! By Gregg Prescott, M.S.

Scientists Discover Another Earth!

NASA’s Kepler Space Telescope recently discovered an Earth-like planet orbiting a nearby star within the habitable zone of our galaxy. Kepler-186f is approximately 500 light-years from Earth in the Cygnus constellation. The habitable zone, also known as the Goldilocks zone, is the region around a star within which planetary-mass objects with sufficient atmospheric pressure can support liquid water at their surfaces. While it has been estimated that there are at least 40 billion Earth-sized planets orbiting in our Milky Way Galaxy, this particular discovery is labeled the first Earth-sized planet to be found in the habitable zone of another star.

What does this mean? In addition to Kepler-186f, there are 4 other planets that orbit a nearby star within the Kepler-186f system. “We know of just one planet where life exists – Earth. Solar via: Tags: Popular.