Unlike planets, comets move on highly elongated orbits, and therefore are visible only at short periods close to the Sun.
The main part of any comet is its nucleus .
According to the hypothesis of the famous American researcher of comets Fred Lawrence Whipple, cometary nucleus is an ice consisting of a mixture of frozen water and frozen gases interspersed with refractory rocky and metallic particles . Figuratively speaking, it looks like a “dirty iceberg”.
Let us imagine that we see the newly opened the comet, which is somewhere in the vicinity of Jupiter’s orbit. Seeing through the telescope hazy pale speck, like a spherical nebula (such unattractive are presented to the observer of a distant comet), we may be disappointed at first. With the approach of the comet to the Sun the solar flux increases. Comet “ice” begin to evaporate rapidly. Around the nucleus formed a vast glowing gas shell – coma. Together with the core of it is the head of the comet. Continue reading
So far the only scientifically proven the possibility of interstellar travel is the acceleration of the spacecraft up to relativistic speeds (punctures and convolution space still remain purely speculative projects). The ship may abandon astronauts in suspended animation for a dozen or even a hundred light years and return them to Earth. But because of the relativistic slowing of Board time on earth will pass away not even the century and Millennium — and it is somehow not pleasing. In addition to other galaxies to get to, there’s no cryostasis will not help. But it is possible that the output is still there.
For 15 years Professor of theoretical physics at Imperial College London, Joao Magueijo develops the hypothesis of variable speed of light (Varying Speed of Light, VSL). However, he minded very little, since most scientists believe this idea is pure nonsense. But we are talking about science impossible, so will try to temper my skepticism.
VSL-models calculated in several ways. They all say that measured on Earth the speed of light in a vacuum is not an absolute constant, and only the lower limit of the speed of propagation of electromagnetic waves. In certain (frankly, vesimaailma) conditions may be many times 299 792 km/s. Continue reading
Flight to Mars is planned by several countries, who are ready to launch to the red planet manned spacecraft within the next 30 years. However, despite such promising prospects, scholars continue to argue about the feasibility of such a flight.
You should start with the fact that one-way flight will take on a variety of calculations, from 7 to 9 months. Such a long flight is very dangerous as the technical side (increasing the probability of hardware failures) and physiological and also the psychological side. Will the astronauts be so many months in a confined space with very limited contacts? How will it affect the human body for long periods in a weightless condition? How great is the danger of radiation in interplanetary space? All these questions become very relevant in the context of emerging in a not too distant future flight to the red planet.
However, should carefully consider possible consequences and unforeseen circumstances that may confront astronauts involved in such a long expedition. First of all, you should bear in mind that absolutely not possible to interrupt the mission due to any circumstances, or to deliver to Mars new reserves in case of shortage. In this case the crew can only rely on their own strength. Continue reading