The Moon moves away from the earth of about 3.8 centimetres per year.

The distance between the Earth and Moon (384,403 km) is measured very precisely using mirrors were deposited on the Moon in the years 1969 to 1971 by astronauts of the Apollo missions. These mirrors are used to reflect a laser beam sent from Earth. The distance travelled by the beam is calculated from the speed of light (299,792,458 meters per second) by measuring the time taken for the beam to return to its starting point (about 2.56 seconds).

The reflector landed on the moon during the Apollo 11 mission in 1969

The Moon exerts a gravitational pull on Earth, which results in the formation of the tides. These tides above the Moon in its rotation around the Earth (because the Earth spins faster on itself and the moon around the Earth), and exert a slight pull on the moon, which then tend to accelerate and s ’distance (indeed, a celestial body orbiting speeding away).

The Hens have wings, they can fly a few feet and go to perch in trees, but they are unable to fly high like other birds. This species has indeed lost its ability to fly during its evolution, like ostriches, penguins and kiwis.

The wild species, the golden rooster, is also gifted little for the flight: these birds that fly only to reach a perch at sunset, or to escape predators.

The chicken is part of the family Phasanidae, which also includes the partridge, pheasants, quail and peacocks. Most of these birds are looking for food on land, and not fly in an emergency only. Some species of this family, like the francolins, almost never fly.

Yellow-necked Francolin

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The "Rosetta Project" is a project launched by specialists in the language, supported by the University of California at Stanford, which is to store and safeguard human languages. There are approximately 7000 languages spoken on Earth, and it is estimated that 50% to 90% of them will disappear during the 21st century.

The Rosetta Project archive over 2300 different languages, in the form of documentation (descriptions language texts and translations of famous passages of the Bible, Universal Declaration of Human Rights of the United Nations, etc.). Documents and audio . The archives are freely accessible on the Internet.

The material collected was engraved on a microdisk nickel whose 15000 pages can be read after a magnification microscope. The idea is modeled after the "Rosetta Stone" (this stone contains text engraved in both Greek and hieroglyphics, and enabled Jean-Francois Champollion to decipher Egyptian hieroglyphics in 1822).

The Rosetta Stone, kept at the British Museum in London

The disc 7 centimeters in diameter shall be kept in a steel spherical container, the upper part of which is a lens grossissante glass.

The disc when viewed from above

The container viewed from the side

The container disassembled