“Once-in-a-lifetime” cosmic explosion is likely this summer, NASA says. Here’s what to know.

A rare burst of light from a dead star will likely be visible to people in Earth this summer in a fleeting but potentially vivid celestial display that scientists are calling “a once-in-a-lifetime event.”

The technical term for the impending cosmic explosion is nova, which happens when a white dwarf lights up suddenly and often impressively in the night sky. “White dwarf” is how astronomers describe a star at the end of its life cycle, after it has exhausted all of its nuclear fuel and only its core remains. Unlike a supernova — another solar phenomenon visible from Earth, when a star effectively explodes – a nova, instead, refers to a dramatic ejection of material that a white dwarf has accumulated over time from a younger star in its proximity.

“It’s a unique event that will create a lot of new astronomers out there, giving young people a cosmic event that they can observe for themselves, ask their own questions and collect their own data,” said Rebekah Hounsell, an assistant research scientist at Goddard Space Flight NASA Center, which specializes in nova events, in a statement. “This will feed the next generation of scientists.”

Between now and September, scientists expect a nova in the Corona Boreal, or North Corona, of Milky Way will send such a powerful flash to space that the naked eye can witness this, NASA announced recently. It will materialize in a dark spot in the constellation, where violent interactions between a white dwarf and a red giant are expected to culminate in this huge explosion.

A red giant is a dying star in the final phase of its life cycle, becoming increasingly turbulent as it expands and periodically expels material from its outer layers in intense episodes.

Known together as T Coronae Borealis, also called the “Blaze Star,” the white dwarf and red giant predicted to create a nova this summer make up a binary star system in the Northern Corona, located about 3,000 light-years from Earth. The red giant in this pair is constantly being stripped of hydrogen as it continues along its path toward total collapse, while the nearby white dwarf pulls that material into its own orbit, according to NASA. Hydrogen diverted from the red giant accumulates on the white dwarf’s surface over several decades, until heat and pressure build to such a point that it triggers a full-blown thermonuclear explosion.

The explosion, similar to a nuclear bomb in its appearance, frees the dead star this excess material. The flare will likely be visible from Earth for about a week before disappearing again, but both the white dwarf and red giant in the Blaze Star system will still be intact whenever it disappears. At that point, the process of hydrogen accumulation between the two stars restarts and will continue until the accumulation of material on the white dwarf reaches its threshold the next time and explodes abruptly.

Different binary systems like T Coronae Borealis go through this cycle at different speeds. A nova typically erupts from the Blaze Star every 80 years or so.

“There are some recurring novae with very short cycles, but we typically don’t often see a repeat burst in a human lifetime, and rarely one so relatively close to our own system,” Hounsell said. “It’s incredibly exciting to have this front row seat.”

When the T-nova Coronae Borealis eventually occurs, it will be the first such pair witnessed on Earth since 1946, according to NASA. The agency advised hopeful observers to look for the Northern Crown, which it describes as “a horseshoe-shaped curve of stars west of the constellation Hercules,” on clear nights. NASA also encouraged citizens to observe the phenomenon as best they could, although its own scientists studied the nova at its peak and during its decline.

“But it is equally critical to obtain data during the onset of the eruption,” said Hounsell, “so the data collected by the eager citizen scientists who are now searching for the nova will contribute dramatically to our discoveries.”