This summer, Earthlings might witness a rare cosmic event as a nova, or a sudden eruption of light from a dead star, is predicted to become visible. Scientists are calling it a “once-in-a-lifetime event.”
What is a Nova?
A nova occurs when a white dwarf—a star that has exhausted its nuclear fuel and is left with only its core—suddenly lights up in the night sky. Unlike a supernova, where a star explodes, a nova involves the dramatic ejection of material that a white dwarf has accumulated from a nearby younger star.
A unique opportunity for astronomers
“It’s a once-in-a-lifetime event that will create a lot of new astronomers out there, giving young people a cosmic event they can observe for themselves, ask their own questions, and collect their own data,” said Rebekah Hounsell, assistant research scientist at NASA‘s Goddard Space Flight Center. “It’ll fuel the next generation of scientists.”
Between now and September, a nova is expected to light up in the Corona Borealis, or Northern Crown, of the Milky Way. NASA announced that this event will be visible to the naked eye, originating from a dark spot in the constellation due to interactions between a white dwarf and a red giant.
The science behind the spectacle
A red giant is a dying star in its final phase, expanding and expelling material from its outer layers. The system known as T Coronae Borealis, or “Blaze Star,” comprises a white dwarf and a red giant about 3,000 light-years from Earth. The red giant is being stripped of hydrogen, which the white dwarf then accumulates until it triggers a thermonuclear explosion.
Duration and impact
The blast, similar in appearance to a nuclear explosion, will likely be visible on Earth for about a week. After the eruption fades, the white dwarf and red giant will remain intact, beginning the cycle anew. T Coronae Borealis typically experiences a nova every 80 years or so.
“There are a few recurrent novae with very short cycles, but typically, we don’t often see a repeated outburst in a human lifetime, and rarely one so relatively close to our own system,” Hounsell explained. “It’s incredibly exciting to have this front-row seat.”
Viewing the event
This will be the first nova from T Coronae Borealis visible from Earth since 1946. NASA advises stargazers to look for the Northern Crown, described as a “horseshoe-shaped curve of stars west of the Hercules constellation,” on clear nights. The agency encourages citizens to observe the phenomenon, as the data collected by amateur astronomers will be crucial for scientific studies.
“But it’s equally critical to obtain data during the early rise to eruption,” said Hounsell. “So the data collected by those avid citizen scientists on the lookout now for the nova will contribute dramatically to our findings.”
