Space NEWS #9 (Gravitational waves detected!)

Hi,
those news are extremely important for modern science, lets just see what is it about.


So today, 11.2.2016 gravitational waves were for the first time detected directly. I already wrote post about gravitational waves here, but anyway in short those are the ripples in space-time made by object accelerating through space-time. Such gravitational waves were predicted by Einstein in his theory of relativity but it took a long time to detect them.

Why? Well gravity is very weak force compared to other fundamental forces so there must be a great of source of so we are able to detect those waves.

This time the source here were two merging black holes. All this information is important since they are black holes which means that they are heavy (36 and 29 solar masses) and also they are merging which means that this acceleration is pretty huge when they rotate towards each other. They merged a black hole of 62 solar masses, the missing mass was converted to gravitational waves, not kidding.

As Phil Plait writes:

And the amount of energy is staggering: This single event released as much energy as the Sun does in 15 trillion years.

How did scientists find this out?

On this video you can watch how it works, anyway here you go if you do not like links:

There is a laser in closed tube. This laser fires hitting glass which splits it on two parts with one beam going in the right angle to the other. Both hit mirrors which are hundreds of meters away. The beams bounce back hitting the mirror which means that they come together. Normally their wavelength will cancel out:

Above the red line is the wave that when everything is normal is canceled out (it is straight line) but when gravitational wave passes one mirror will move a little bit so the light will not cancel but rather go through, towards detector. Here you go, you have just found a gravitational wave!

Dragallur

Gif from here.