Occultation: the brief phenomenon that will hit the huge star Betelgeuse next Monday (and where it can be observed)

One of the largest and brightest stars in the sky will ‘disappear’ for a few seconds this Monday evening, December 11, 2023.

Betelgeuse, the reddish and enormous star in the constellation Orion, will be eclipsed by the passage of the asteroid (319) Leona that will pass in front of it, from Earth’s perspective.

Leona is an asteroid about 50 km wide that orbits between Mars and Jupiter.

The event is known as occultation occurs when a celestial body closer to the observer appears larger, completely hiding the more distant object.

This extremely rare phenomenon will be visible in southern Italy, the southern reaches of Sardinia, Greece and Turkey, as well as in Spain and Portugal.

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On the American continent It can be seen from the south of the state of Florida on December 11 around 8:20 PM (local time) and an hour earlier in Mexico.

If you are not in these areas, the specialist site Virtual Telescope Project 2.0 will broadcast this live on its website.

Hiding takes between 7 and 15 seconds.

What is and where is Betelgeuse?

Seen from Earth, Betelgeuse is a gigantic red star, located on the left shoulder of the hunter figure describing the constellation Orion.

It is about 10 million years old. That’s that It is considerably younger than our Sun, but 700 times larger and between 7,500 and 14,000 times brighter..

It is expected to end its life in a stellar explosion known as a supernova within a relatively short time in astronomical terms: between 1,000 and 100,000 years.

In 2019, Betelgeuse began to dim slightly, sparking speculation in the scientific community about the fate of the famous red star. Some even thought it was about to explode.

But It was discovered that the star’s dimming was due to part of its atmosphere being ejected into space..

In March 2020, astronomers noted that brightness had recovered and returned to normal.

All these activities have fascinated astronomers, both professional and amateur, who will be once again fascinated by the occult this Monday evening (or Tuesday morning, if you are in Europe).

What is a concealment

Occultation is the visible effect of a conjunction, where two stars, observed from a third, are on the same celestial length. It differs from an eclipse or astronomical transit in that the nearest object appears larger and completely obscures the more distant one.

We speak of an eclipse when the sizes of the bodies are comparable. So during solar eclipses the apparent sizes of our star and our satellite are almost equal, so that the moon completely covers the sun.

During a transit, the closest object appears much smaller compared to the more distant object. Like when Mercury stops in front of the Sun and looks like a dark dot running across the surface of our star.

The most well-known occultations for amateur astronomers are lunar occultations and they mainly occur near planets.

These occur when a planet in the solar system appears to pass behind the moon and then emerge on the other side.

During a lunar occultation, the planet is not actually close to the moon, but only appears that way from our perspective on Earth.

The same will happen with the occultation of Betelgeuse by the asteroid Leona. The two celestial bodies appear very close together, but the star is actually thousands of light years away from the asteroid.

The most recent lunar occultations of planets include the lunar occultation of Venus on November 8, 2023 and the lunar occultation of Mars on December 8, 2022..

What can we learn from a cover-up?

It’s not just the spectacle of the event that attracts professional astronomers. Their observations will be of great scientific importance and they will be ready to collect all possible information about the occultation.

Stellar occultations by asteroids They can help measure the diameter of these bodies and also calculate their shape and characteristics.

The phenomenon can also reveal information about the star, including its surface and whether the star has a previously unknown companion.

Scientists also hope to use the event to map the star’s “strange, large connecting cells” that make it bright and dim for long periods, according to the specialist website Sky and Telescope.