New Delhi, April 26 (IANS). We often read that planets revolve around their stars, but from the point of view of science this is not completely correct. In fact, both the planet and the star revolve around a common point, called the “barycenter”. This concept plays a very important role in understanding space science and discovering new planets.
If we understand Barycenter in simple language, it is the combined center of mass of any two or more objects. Every object has its own center of mass – the point where its entire weight can be balanced. For example, by balancing a simple ruler on a finger its center of mass is easily determined.
However, not all objects have their center of mass exactly in the middle. If one part of an object is more heavy, its center of mass shifts in the same direction. The same principle applies in space also.
In space, when two celestial bodies – such as a planet and a star – are bound to each other by gravity, they do not rotate around each other, but around their shared center of mass, i.e. the barycenter. Usually this point is closer to the body which has more mass.
Take the Sun and the Earth for example. The mass of the Sun is much greater than that of the Earth, so the barycenter of both of them is very close to the center of the Sun. This is why we think the Earth is revolving around the Sun. But matters become interesting when we look at Jupiter. Jupiter’s mass is very high, due to which its and the Sun’s barycenters may lie outside the Sun. In such a situation, the Sun itself appears to be slightly “wobbly”.
Actually, our entire solar system also has a collective barycenter, around which all the planets and the Sun rotate. This point does not remain constant, but keeps changing according to the position of the planets. Sometimes it happens inside the Sun, and sometimes outside its surface.
This concept of barycenter helps astronomers find planets outside the solar system called exoplanets. It is very difficult to see planets revolving around distant stars directly, because their brightness gets hidden in the light of their star. In such a situation, scientists measure the slight “wobble” of that star. This wobble indicates that there is a planet around the star and both are rotating around a common barycenter. With the help of this technology, thousands of exoplanets have been discovered so far.
In this way, the barycenter not only helps in understanding the movement of our solar system, but it has also become an important basis for the discovery of new planets in the universe.
–IANS
MT/AS