By cracking open a cosmic Russian nesting doll, astronomers have discovered what appears to be a miniature spiral galaxy, swirling daintily around a single giant star.
The star, as mentioned above, is located about 26,000 light-years from Earth near the dense and dusty galactic center, is about 32 times as massive as the sun, and sits within an enormous disk of swirling gas, known as a “protostellar disk.” This protostellar disk measures about 4,000 astronomical units wide – or 4,000 times the distance between Earth and the Sun.
These discussed sheets are widespread in the universe, serving as stellar fuel that helps young stars grow into enormous, bright suns over millions of years.
Surprisingly, this newly discovered disk has features that have never been studied before. It appears to be a galaxy in miniature, orbiting perilously close to the center of our universe. It raises multiple questions like, How did this mini-spiral come to be, and are there more like it out there?
This mystery can be solved through this mysterious object only. According to a study published May 30 in the journal Nature Astronomy, It happens to be about three times as massive as Earth’s sun, lurking just outside the spiral disk’s orbit.
With the help of the Atacama Large Millimeter/submillimeter Array (ALMA) telescope in Chile, the scientists uncovered that the disk doesn’t appear to be moving in a way that would give it a natural spiral shape. In fact, through the data published, it is found that the disk seems to have been stirred up by a near-collision with another body – possibly the mysterious triple-sun-sized object that’s still visible nearby it.
Many calculations have been performed to check this hypothesis. Through them, it is found that it could have skimmed past the disk about 12,000 years ago, perturbing the dust just enough to result in the vivid spiral shape seen today.
A statement by an associate researcher from the Shanghai Astronomical Observatory of the Chinese Academy of Sciences, Lu Xing, reads, “The nice match among analytical calculations, the numerical simulation, and the ALMA observations provide robust evidence that the spiral arms in the disk are relics of the flyby of the intruding object.”