Astronomers capture first evidence of star’s “double explosion”

For the first time, astronomers have obtained striking visual evidence of a star’s “double explosion,” revealing how it ultimately destroyed itself in a rare cosmic event.

The twin eruption was identified through observations of two concentric calcium rings surrounding “SNR 0509-67.5”, which is the remnant of a star that perished in a “type Ia” supernova centuries ago, according to an article by Live Science.

In a peer-reviewed study published in Nature Astronomy, the researchers describe two distinct calcium-rich shells with a single layer of sulfur positioned between them.

The scientists behind the discovery note that much of our understanding of the universe’s expansion — a central issue in modern cosmology — relies on accurate measurements of this type of supernova, which also serves as the universe’s main producer of iron.

For these reasons, “the explosions of white dwarfs play a crucial role in astronomy,” said study first author Priyam Das, a graduate student at the University of New South Wales Canberra in Australia. “Yet, despite their importance, the long-standing puzzle of the exact mechanism triggering their explosion remains unsolved.”

A “Type Ia” supernovas occur when a dead star’s dense core — a white dwarf — siphons material from its companion star, leading to a massive thermonuclear blast.

However, not all detonation processes in white dwarfs are fully understood. According to the article, astronomers have long assumed that these stellar remnants steadily pull in matter from a nearby star until they reach the Chandrasekhar limit — a critical mass threshold — and then explode. But mounting evidence suggests that this isn’t the only way such stellar husks meet their fiery end.

By Nazrin Sadigova