Scientists have always wondered why the star system behaves this way and whether it is because of some strange supernova or a cataclysmic explosion. Now, a team of researchers has figured out that this has been happening since the 13th century.
 

Researchers suggest that for the first time in the mid-1800s, scientists had witnessed this unusual phenomenon. A star named Eta Carinae - which was previously inconspicuous - had started to grow brighter and brighter. It practically outshines all other stars, except Sirius.

However, it soon faded over the next decade. The dimness was so severe that it became nearly impossible to see the star with the naked eyes, according to Astronomy Now.

According to Megan Kaminski of the University of Arizona's Department of Astronomy and Steward Observatory, Eta Carinae, also knows as "supernova impostor," has been growing bright and blowing off a lot of material, but it is still there in the universe.

Back in the 20th century, the star brightened again. However, the "Great Eruption" of the 1880s was enough to list the weird star in the list of celebrity objects. Eta Carinae is surrounded by hourglass-shaped, glowing clouds of gas and dust. The clouds also contain stellar material that emerged as a result of the Great Eruption.

The recent study findings, published in the journal Monthly Notices of the Royal Astronomical Society, reveal that the Great Eruption was only the latest event in the series if similar events that have already been taking place since the 13th century.

An analysis of the expansion rate of the gas within clouds that do not immediately surround the star indicates that it was ejected fast before the brightening that occurred in the 1800s. In fact, it is now estimated that two more eruptions had already taken place well before the 19th century, one on the 13th century and the other one in the 15th century.

For researchers, the study has been like analyzing the eruption history of a volcano and then reconstructing it by discovering the flow of lava.