They exist in fact, the gravitational waves, which predicted by Albert Einstein? Lisa Pathfinder will find out. The ESA satellite started yesterday in the space.
100 years ago, Albert Einstein presented the theory of general relativity, and so transform the world view of physics. Part of the theory: Star explosions or black holes falling into emit so-called gravitational waves that spread out in space with the speed of light and bend the space. While there are no serious doubts as to its existence in the science, but to prove she could no one so far. The European Space Agency ESA wants to change this.
Launch of ESA Lisa Pathfinder satellite into space
As the potential discoverer of gravity waves, the ESA has chosen a satellite called Lisa Pathfinder. He is yesterday into space started – from the European space station Kourou (French Guiana) – and now flies Sun 1.5 km in the direction. There, on the Lagrangepunkt L1, the gravitational forces of the Sun and Earth balance is almost. Perfect conditions for measurements, to launch the satellite from mid February 2016.
And so Lisa Pathfinder is the gravitational waves on the track: inside the float at a distance of 35 cm two cube-shaped test mass from a Gold-Platinum alloy, 46 mm wide and 2 kg in weight, almost completely unaffected by interference from the spacecraft itself and the outside world. A laser continuously measures the distance of the cube. A gravitational wave crosses the apparatus, the distance would change slightly.
The problem: At a small distance of 35 cm the influence is only difficult to determine, as the focus on an example shows. On a ruler a million km in length, he would not even have to exceed the size of an atom. The likelihood that Lisa Pathfinder actually finds something is accordingly low. That would be no reason to shed tears for the scientists. Because basically it comes them primarily to test the technology. Because a much larger mission is on the horizon.
Mission eLisa is a gigantic triangle in space
The ESA wants to increase the measuring distance in the mission eLisa: from 2034, three probes are to form a gigantic triangle with an edge length of 2 million km in space and detect gravitational waves with lasers. They have a much higher chance of success when compared to the current measuring distance of 35 cm. That would allow a new look way on phenomena of the universe, astronomers – for example, on the interaction of black holes. So far, they observe the universe with the help of visible light, infrared and ultraviolet radiation, as well as radio, X-ray and gamma radiation.