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 The importance of eclipsing binary stars is when they are studied in detail; they allow us, for example, to calculate the radius of the stars and their brightness and, combining other special measurement instruments, we can measure their masses. All of this to understand better how they are formed and evolve.

DID YOU KNOW THAT…

in spite of the eclipses of distant stars, there are two phenomena similar to an eclipse: occultations and transits.

OCCULTATIONS

In our Solar System, besides the planets, there are thousands of asteroids, comets, and distant objects beyond the orbit of Neptune called trans Neptunians objects.

The best example and largest one of these objects are Pluto and its moons but there are many others in what is known as the Kuiper Belt.

On some occasions, these objects pass between a distant star and us and block the light of the star.

This phenomenon is called occultation, and it is the best way to study the Trans-Neptunian object’s shape that is hiding the starlight. In the case of planets, it has no advantages to carry a more extensive study since they are a lot, and we can measure their sizes using telescopes and probes, whereas for small bodies, such as some asteroids or trans-Neptunian objects from the Kuiper belt, is very useful.

To study the trans-Neptunian objects, we have to know very well its orbits, this is the only way we have to predict when they are going to pass between us and a star. With the calculations made, we are going to determine from which parts of the Earth they can be observed (as they are small, the occultation is not visible from every part of the Earth). Generally, when this phenomenon is recognized, an astronomical alarm is set for observatories and amateur observers to follow the event.

Having said that, as the object is small, the observations carried out in different regions of the Earth have different perspectives and the duration of the occultation changes depending on our point of view. To better describe the shape of the object and its size, we get all observations together, including the position of observers, and we analyze the process case by case.

It seems to be easy at first. However, we have to consider that occultations last only a few minutes or even seconds, so there are needed telescopes with cameras set up to take many images in a short period.

Among the most exciting findings achieved due to the observations of these occultations, it stands out the discovery of binary trans-Neptunian objects or asteroids with rings. A mini version of Saturn! 82 • • •