Astronomers Investigate Whether Dying Star's Blast of Deadly Gamma Radiation Will Hit Earth
For over a decade, a star system on the verge of unleashing a deadly gamma ray burst appeared to have its guns trained on Earth.
The so-called "Death Star," which is also famed for looking like a glowing pinwheel, has caused a lot of lost sleep among astronomers. But now they — and the entire planet — may finally breathe a sigh of relief.
In a recent study published in the Monthly Notices of the Royal Astronomical Society, a team of researchers at the Keck Observatory in Hawai'i took a closer look at the system, Wolf-Rayet 104, confirming that its unique appearance is the result of its two constituent stars dancing around each other as they each give off a mesmerizing wind of luminous gases.
But surprisingly, the astronomers also found that the orientation of the stars' orbits isn't what it was long assumed to be — with the optimistic upshot that, when it does explode, the Earth won't be caught in the crossfire. Hooray!
"When I started this project, I thought the main focus would be the colliding winds and a face-on orbit was a given," study author Grant Hill of Keck Observatory said in a statement. "Instead, I found something very unexpected. The orbit is tilted at least 30 or 40 degrees out of the plane of the sky."
WR 104's primary star is known as a Wolf-Rayet, a type of uber-hot and extraordinarily massive star — typically 25 or more times as massive as our own Sun — that's quickly dying.
In a dramatic prelude to their impending demise, Wolf-Rayets rapidly cast off their outer layers, which get swept up by the star's powerful wind. In WR 104's case, the Wolf-Rayet's wind collides with the wind of its orbital companion, an even more massive star, creating a pinwheel of swirling dust that glows in the infrared spectrum, the astronomers found.
The spectacle is soon doomed to end in a supernova, tragically. Wolf-Rayets have lifespans only in the hundreds of thousands of years, opening the possibility that the gamma ray burst it would unleash upon exploding could barrage our planet with deadly radiation in the not-so-distant — on a cosmic scale, at least — future.
It looks like Earth will be spared this fate. Yet the mysteries of the "Death Star" abound. How does this star appear to face us, even though the poles of its axis don't, can't yet be explained.
"This is such a great example of how with astronomy we often begin a study and the universe surprises us with mysteries we didn't expect," Hill said in the statement. "In this case, WR 104 is not done surprising us yet."
More on astronomy: Get Ready to Watch This Star Explode
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