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If you came of age during the ‘90s, there’s a decent chance that the 1996 Freaky Friday-style body swap movie Wish Upon a Star (streaming now on Peacock) had a chokehold on your psyche. It stars Katherine Heigl and Danielle Harris as Alexia and Haley Wheaton, two teenage sisters who couldn’t be more different from one another, and don’t get along.

One night, both sisters are outside beneath the moonlight, one of them studying and the other flirting, when a shooting star cuts across the sky. Despite their caustic relationship, each of them is secretly envious of the other, and they make a wish. After a few days walking in each other’s bodies, they realize they can only get out of this predicament the same way they got into it, and the hunt for a wishing star begins.

Whether you’re looking to body swap with someone or you’re just a fan of astronomical events, real-world skywatchers will have a chance to see a fleeting star in the night sky, sometime between now and September 2024. Unlike the shooting stars we usually wish upon, which are actually bits of rock and dust burning up in the atmosphere, this is an actual star which will temporarily become significantly brighter before dimming again.

For More on Stars:
Did Scientists Find Evidence of Alien Megastructures in the Milky Way?
Some of the Universe’s Oldest Stars Have Been Found Circling Our Own Galaxy
What We Know about Mizar-Alcor, the Home of Resident Alien’s Harry Vanderspeigle

Astronomers Predict the Blaze Star Is About to Erupt

The star T Coronae Borealis, commonly known as the Blaze Star, is expected to set off an explosion so bright that you’ll be able to see it with the naked eye from 3,000 light-years away. The Blaze Star was last visible to skywatchers in 1946 and ever since then it’s been ramping up to its next explosion. Before we get into that, a note about the apparent brightness of stars.

In astronomy, the apparent brightness of an object (how bright it appears from Earth, as opposed to its true brightness) is called its magnitude. Counterintuitively, the lower its magnitude, the brighter an object is. The Moon, the brightest object in the night sky, has a magnitude of -12.6. Venus, the brightest planet, has a magnitude -4.6, and the three brightest stars in Orion’s Belt have magnitudes of 1.77, 1.69, and 2.23. On average and on a clear night, the dimmest objects you can see with the naked eye have a magnitude of about 6.5.

Roughly speaking, a difference in magnitude of 1, corresponds to an increase or decrease in brightness of about 2.5. Put simply, a magnitude 1 star is 2.5 times brighter than a magnitude 2 star, and so on. It’s not exactly an intuitive scale but that should give you a sense of the kinds of ranges you typically see when you look at the stars with your eyes.

On an ordinary day, the Blaze Star has a magnitude of 10. That’s too dim to see unaided, but bright enough to see with some decent binoculars or a small telescope. Sometime between now and September, its magnitude is expected to brighten dramatically from 10 to 2, more than 1,500 times brighter than normal.

What Causes the Blaze Star and How to Find It

The secret to the Blaze Star’s periodic light explosions is that it’s actually two stars in a gravitational dance. There’s a massive red giant and a smaller but still massive white dwarf (about the size of the Earth, with the mass of the Sun), both nestled inside the Northern Crown constellation. As the two sister stars orbit one another, the red giant dumps hydrogen onto the surface of the white dwarf. Over time, that hydrogen stacks up, the heat and pressure continually mounting until it blooms into a violent thermonuclear explosion, blasting the collected hydrogen into space like so much cosmic shrapnel. These recurrent novas happen every 80 years or so and are preceded by signs.

In the years leading up to the last two explosions in 1866 and 1946, the Blaze Star got brighter, then dimmed again, before exploding. Astronomers have noticed the same pattern unfolding over the last decade. It started growing brighter back in 2015, then dimmed in March 2023. When it goes off, it will be about as bright as Polaris, the North Star, and it’s expected to stay that bright for a few days.

To find it, search for the Big Dipper. Follow the arc of its handle from east to west to the bright star Arcturus. Draw a line between Arcturus and Vega, and you’ll find the Northern Crown (Corona Borealis) perched in the middle. If you look tonight, you won’t see the Blaze Star (unless it has gone off by the time you’re reading this) but some night soon, a new star will emerge there for a brief visit, and it won’t come back for another 80 years.

Catch Wish Upon a Star, streaming now on Peacock.