Comets: the oldest inhabitants of the Solar system
J. L. Lagrange (1813) was also based on firmly established facts – the presence of comets that definitely move in elliptical orbits, including short-period. He explained the origin of comets gigantic volcanic explosions – emissions (eruption) with giant planets. It is, in principle, could explain the nature of the orbits of short-period comets. Subsequently, the views of La Grange shared and developed a number of scientists, among which the most important contribution of the Soviet astronomer S. K. Bo, who worked in this direction with the 20-ies to 80-ies of our century. He has eliminated the biggest internal difficulty is the concept of Lagrange – the necessity of the ejection of cometary masses (nuclei) with the “surface” of the giant planets with their powerful gravity fields, the overcoming of which requires an initial speed of 60 km/s and more. Giant planets also have thick (the length of many thousands of miles) and very dense atmosphere, in the middle of the twentieth century has been very problematic the very existence of a solid surface planets – giants beneath these atmospheres. Continue reading
“Our observation was aimed at studying the chemical composition of the comet Tempel 1,” says Michael Mumma (Michael Turner) from space flight Center NASA Goddard (NASA Goddard Space Flight Center). The Mumma and his colleagues used a powerful telescope, the Keck Observatory in Hawaii for a detailed analysis of the light emitted by the gas of the comet at the moment of impact. Since each type of atoms and molecules has its own characteristic frequency of radiation, on the basis of this, scientists were able to determine the chemical composition of the comet’s nucleus.
Comets are blocks, which consist of ice and dust that move in elongated orbits. It is believed that the nucleus of the comet is gas and dust formations, remaining after the formation of the main bodies of the solar system.
When approaching the Sun, its radiation heats the comet’s nucleus, releasing dust and gas. The latter form a coma (cloud around the nucleus) and one or more tails. Repeated heating leads to the fact that disappear from the surface of the substance having a low boiling point. In fact, the nucleus of a comet is formed “crust” that is different chemically from its internal regions. This makes it difficult to determine the true composition of the comet just by studying the gas in its tail. Continue reading
The U.S. space Agency plans to launch a probe, equipped with a solar sail. He will leave earth orbit and go to the distant asteroid due to the pressure of sunlight. Like the ships of the discoverers of the 15th century, in 2018, a small space probe will unfurl the sail and start a journey to a faraway asteroid, marking the beginning of a new phase in space exploration.
The idea of using solar sails for space flight was proposed almost a hundred years ago, Soviet rocketry pioneer Friedrich Zander. It was based on the fact that Photons of light can exert pressure on the illuminated surface, giving him his momentum. Therefore, if you expand behind the ship a giant mirror, his speed will gradually increase without using fuel.
However, the first experimental devices were established only at the very end of the twentieth century. This is because space sailboats should be very easy, and their embodiment in life became possible only after the emergence of a truly compact electronics. Continue reading