The James Webb Space Telescope has discovered the oldest and most distant supernova ever seen, a stellar explosion that occurred when the universe was only 1.8 billion years old. The ancient starburst was found among 80 other stars in a patch of sky the width of a grain of rice held at an arm’s length from our vantage point on Earth.

Supernovae are transient objects because their brightness changes over time. This makes new explosion series of distant stars particularly exciting; because studying them could provide important insights into unresolved questions about how the early universe grew. The researchers presented their findings on June 10. 244th Meeting of the American Astronomical Society In Madison, Wisconsin.

Astronomer Matthew Siebert, who conducted the spectroscopic analysis of supernovae, said in a statement: “We are actually opening a new window into the transient universe.” “Historically, every time we’ve done this we’ve found really exciting things—things we didn’t expect.”

There are two main categories of supernovae: core collapse and thermonuclear supernovae.

Category 1 explosions occur when stars with a mass at least eight times our Sun run out of fuel and collapse in on themselves before expanding outward again in a massive explosion.

The second, known as a Type Ia supernova, occurs when two stars spiral towards each other, one of which is a collapsed shell star called a white dwarf. This causes the white dwarf to absorb hydrogen from the star it orbits, creating a reaction that results in a giant thermonuclear explosion.

Type Ia supernovae are of particular interest to astrophysicists because their explosions are thought to always have the same brightness, making them “standard candles” with which astronomers can measure long distances and calculate the expansion rate of the universe, known as Hubble. continuous.

But attempts to measure the Hubble constant using these standard candles and other methods have produced a troubling discrepancy; The universe appears to be expanding at different rates depending on where we look. This problem, known as the Hubble tension, has cast serious doubt on the Standard Model of cosmology and made the search for standard candles over the lifetime of the universe a major challenge for astronomers.

Researchers discovered ancient supernovae using data from the JWST Advanced Deep Extragalactic Survey (JADES). The research was carried out by taking several photographs of the same area of ​​the sky, one year apart. By looking at new points of light that appeared or disappeared in successive images, the researchers identified supernovae, some of which were Type Ia explosions.

Now that they have identified extremely distant starbursts, researchers will examine them more closely to determine their metal content and precise distance. They say this will help scientists understand which stars caused the explosions and the conditions of the “pre-teen” universe in which the explosions occurred.

“This is our first example of what it actually looks like [віддалений] “It’s a high-redshift universe for transient science,” astronomer Justin Pirel from the JADES team said in a statement. “We’re trying to determine whether distant supernovae are fundamentally different or very similar to what we see in the nearby universe.”