In search of gravitational waves: LISA "Ranger" clear the way for the mission eLISA - It has been a hundred years since Einstein introduced his theory of general relativity, but it also helps us to reveal the deepest secrets of the universe. Now the mission LISA Pathfinder («Ranger") will prepare a way for us to study the violent events that we have not seen before - such as the creation of massive black holes.
This probe is designed to test the technology needed to launch another mission, eLISA, in 2034, which will look for ripples in space - known as gravitational waves. It is also interesting that this project will help us to test the most extreme aspects of Einstein's general relativity.
General relativity says that gravity is a manifestation of the fact that the weight leads to a distortion of the surrounding space and the curvature of space is the path that passes any other object or light. As the Earth revolves around the sun, the huge mass of light distorts the space around it, allowing less massive earth just follow the most "direct" possible way, but in a curved space: the resulting consequence is known to all of us orbit.
Einstein showed that if there is something related to the distribution of mass, leads to a distortion in the region of space, the curvature changes will propagate with finite velocity - we know it as the speed of light. This spreading ripples of curvature of space called gravitational waves.
Gravity - the force that organizes the universe, but until now only been able to observe some of its most superficial manifestations. Nevertheless, the ability to directly detect and study gravitational waves will open up a whole new window on the universe.
The observations of gravitational waves will allow us to see the intimate details of the creation of massive black holes; supermassive black hole, rotating and twisting as the collision of galaxies; neutron stars and black holes, circling in pairs as long as the merge.
Direct see such events using conventional telescopes measuring electromagnetic radiation possible. This is because Agitated matter, usually surrounding such events will close our review of the solenoid. In addition, black holes, we have never observed directly, it is not radiate electromagnetic spectrum. But Einstein predicted that they will emit gravitational waves in the case of acceleration - as if it were in the orbital system - and hence the detector of gravitational waves would be able to see them.
Big problems - great benefits
The effect of gravitational waves passing relatively simple: the wave stretches the space in one direction, and compresses it in the other at right angles. The detectors of gravitational waves, so-called laser interferometers, existing in the world, the laser beam is split into two perpendicular directions and send them through the long vacuum tube. Then the two tracks recorded back mirrors point from which to start, and where the detector is located. If the laser tracks will be disturbed by gravitational waves in its path, re-gathered the rays reflect changes in the overall brightness.
To catch the richest and most intense signals of gravitational waves would have to go into space. eLISA will be the first space observatory of gravitational waves.
eLISA will consist of three satellites in the arrangement of a triangle with sides of a few million kilometers. Precise measurements of the lengths of the sides will be held between the "test mass" of each spacecraft - free-floating mirrors that reflect the measured laser beams traveling along the sides of the triangle.
eLISA - complex mission. But the scientific exhaust will be enormous. The first step - to make sure that the required sensitivity achievable. To demonstrate this, the mission LISA Pathfinder will show the test weight and the length of the measurement system on the bracket fit into small compact spacecraft. Test weight, ideally, should be move quite calmly, without any interference from outside. Laser interferometer will monitor the separation between them in order to confirm the absence of invisible tiny stray forces.
The British team worked long and hard on a system of laser metrology for "Pathfinder." For them, the launch will be a defining moment, which will mark the beginning of an exciting gravitational wave astronomy in space.