55 million years ago, a dense swarm of ancient stars smashed through the Milky Way’s disk — and may have left behind one of the galaxy’s most mysterious features. Astronomers now believe the globular cluster NGC 4372 could be the culprit behind the Radcliffe Wave, a gigantic, undulating river of gas and dust stretching 8,800 light-years across our galactic neighborhood. This wavy structure, discovered only in 2020, is no static scar: the gas and the young stars forming inside it are still bobbing up and down like a cosmic ripple. Researchers reconstructed the orbits of 152 globular clusters over the past billion years. Most of their 3,000+ crossings of the galactic plane happened closer to the center and left little lasting damage. But one stood out. About 55.5 million years ago, NGC 4372 plunged through the disk at a steep 33-degree angle — exactly the kind of high-impact flyby that could compress interstellar gas, trigger a shock wave, and set material oscillating vertically for tens of millions of years. Twenty-two million years after that collision, star formation flared up in the same region, just as the models predict. The cluster didn’t just pass through; it may have carved a lasting wave that we can still see today. The scientists are careful not to claim absolute proof — NGC 4372 is simply the strongest candidate so far. Their findings, currently available as a preprint, are still awaiting full peer review. But if confirmed, it would mean one of the Milky Way’s oldest stellar fossils once shook the galactic disk hard enough to leave a scar that is still gently waving past our Sun.
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου