Spaceship moving at near-light speed, it can be seen from Earth - VIDEO
Interstellar flights are still only giving the world of science fiction, but in theory they can be implemented. Earthlings do not yet have such technology, but scientists believe that the Universe can live and much more advanced intelligent civilization.
alien researchers at the proper level of development may be able to build a ship, allowing to make interstellar flights. And such a ship, if he were in the foreseeable space for earthlings will be visible to the human instrument, so as to leave a unique light "signature". This conclusion was made in the course of its new research engineers from the company Raytheon, has been developing in the military sphere.
Ulvi Yurtzever (Ulvi Yurtsever) and Stephen Wilkinson (Steven Wilkinson) carefully studied the hypothetical possibility of creating a ship moving at a speed close to light. They note that any objects moving at relativistic speeds, will interact with photons in the cosmic microwave background.
Such interaction should create a special resistance, imposes certain restrictions on the speed that can develop ship. However, this also means that the relativistic space flight will leave behind a unique "signature" in the spectrum of radiation coming to the Earth, which will be visible to the modern Earth devices. However, an alien ship will be to detect only if it flies in our galactic neighborhood.
Recall that the cosmic microwave background radiation, also referred to as the cosmic microwave background, is an "echo" of the Big Bang. This is the first light that appeared in the space-time, and to date, together with the expanding Universe "stretched" to microwave frequencies.
According to the calculations of scientists, each cubic centimeter of the Universe contains more than 400 cosmic microwave photons. This means that the relativistic spaceship traveling through the galaxy will collide with the myriad of particles every second of the CMB.
These collisions will occur at the microscopic level: the photons will fall into the atomic nuclei at high energies (as in the ring of the Large Hadron kollayddera). The principles of particle physics say that any high-energy collisions will produce pairs of electrons and positrons.
Yurtsever and Wilkinson calculated that photons colliding with the ship, which goes to the sub-light speeds, from the look like high-energy gamma rays. If these gamma rays have energies greater than the rest mass of the electron and positron, the collision will produce an electron-positron pair.
Moreover, the calculations showed that a similar process will be followed by a dissipation (scattering) huge amounts of energy. The creation of each particle-antiparticle pairs will result in isolation 1,6 x 10-13 joules.
"Assuming that the area of the spacecraft is about 100 square meters, the dissipative effect will be about two million joules per second," - says Wilkinson.
For a spaceship, at rest, the energy dissipation is even higher, because here comes the effect of relativistic time dilation. Second last longer when the vehicle picks up speed close to the light, and therefore the energy dissipation reaches 1014 joules per second.
For this reason, according to physics, spacecraft engines will have to overcome a very substantial resistance, just to maintain constant speed of the vessel. Therefore, to keep the resistance at insignificant level - just a few joules per second - it is necessary to keep the speed such that the creation of electron-positron pairs from happening at all. And this threshold can be overcome, if the ship is moving at a speed of less than (1 - 3,3 x10-17) the speed of light (which is about light, but a little less than it).
Relativistic motion of the ship will generate another phenomenon. He will dissipate the cosmic microwave background so that leaves a unique "signature" in the radiation reaching the Earth.
"Baryon spaceship coming at relativistic speeds, will interact with the cosmic microwave background radiation, resulting in energy dissipation occurs and the frequency shift, which in turn can be seen from the Earth, if we use the most advanced detectors," - says Wilkinson, whose article appeared online preprints arXiv.org.
The researchers calculated the properties of hypothetical light "signature". It turned out that the scattering should generate radiation in the terahertz-infrared regions of the spectrum and that this signal has to move to the background.
"Characteristic features of the signal - is a rapid drop in temperature followed by a rapid increase in the intensity of energy, along with the motion of the source relative to the reference system. For reference system can take distant quasars and super-bright to be visible from Earth" - says Wilkinson.
Of course, such a scenario is possible only under certain prerequisites. First of all, there must be a space civilization capable of building on the sub-light spacecraft. It is also necessary that the ship was flying within a foreseeable space from Earth.
Finally, it is important to bear in mind that in addition to sub-light photons colliding with a ship coming and collisions with cosmic dust particles, each of which will have the energy to 10,000 megajoules, if the mass of these particles will be about 10-14 grams. So to start the alien engineers as well as the earth, to decide prosaic, but it is a real problem of clearing the road for mezhhvёzdnogo vessel. There is something to smash his head on to future generations of scientists.
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