A supernova that exploded in a nearby galaxy is one of the brightest in a decade. Here's how to see it.

• A supernova has exploded in the Pinwheel Galaxy 21 million light-years away.
• Named SN 2023ixf, it sets itself apart by being one of the brightest seen in a decade.

A supernova exploding in a nearby galaxy is providing an unexpected spectacle for amateur astronomers.

The supernova, which appeared in the Pinwheel Galaxy 21 million light-years away, is one of the biggest and brightest in our skies in a decade, Space.com reported.

Scientists will be keeping a close eye on the discovery, as it can reveal new information on the life and death of neighboring stars.

"It's one of the closest supernovae of our lifetimes, and it was caught very early," Dan Perley, an astrophysicist at Liverpool John Moores Observatory, told Insider.

Here's how you can witness first-hand this rare cosmic event, using a simple telescope.

The supernova is so bright, it was first spotted by an amateur

Supernovae — giant bursts of energy happening when a star dies — aren't rare. In fact, observatories that automatically survey our skies for cosmic events spot several of these each year.

But this supernova, named SN 2023ixf, sets itself apart by its proximity to Earth: it's located in the Pinwheel Galaxy, which is only about 21 million light-years away.

Because of this, the blast was bright enough to be first spotted by an amateur astrophotographer, Koichi Itagaki, on May 19.

While scientists race to collect as much information as possible from this supernova, backyard astronomers can participate by turning their telescopes to the sky to see it with their own eyes.

Head to a quiet spot with a good telescope

The supernova is expected to blaze in the sky for at least a month, and it should visible with a fairly standard telescope, said Perley.

"The magnitude of the supernova is about 11.5 at this time. This is accessible in principle with a telescope of 6 inches (15cm) from a good enough site, seen through an eyepiece," said Perley.

Head to a dark spot, away from city lights, with no moon in the sky for best visibility, he said. The supernova will appear as a "white point of light," so bring a finder as it can be difficult to spot it among the stars, he said.

The galaxy the supernova can be found near the Big Dipper. Look for seven stars that appear to make up the shape of a saucepan, with three making up the handle, and four stars creating the bowl shape.

The Pinwheel Galaxy is located close to two of the stars in the handle of the Big Dipper.

"Seen from a dark site with a good telescope, it will also be superimposed on the outer part of the wispy, diffuse spiral galaxy that it exploded inside of," said Perley.

"If you have the ability to attach a camera capable of taking long exposure to the telescope, this also allows a much deeper and clearer picture than looking through a telescope with the eye alone," he said.

A better understanding of the death of a star

Scientists are scrutinizing this supernova because it happened so close to Earth and was spotted so early, Perley said.

"These supernovae come from massive stars that the core collapse and explodes, we know those basics well," said Perley.

"What we don't know so much is exactly what happens right before that core collapse and explosion," he said.

What Perley and other astronomers are trying to understand is whether the star ejects material before the supernova explodes, a type of shell that could be ejected during this very unstable pre-explosion phase.

Because this supernova is so close, it is a favorite of amateur astrophotographers, which means that astronomers have been able to parce amateur pictures of the galaxy that were even earlier than Itagaki's shot, providing information about the first 24 hours after the blast.

It's also close enough for scientists to pick up on data beyond the ultraviolet, optical, and infrared wavelengths, such as X-ray and radio, which are difficult to pick up for supernovae at greater distances, said Perley.