A recent study suggests that a massive, invisible halo of dark matter has caused a significant distortion in the shape of our galaxy. While scientists initially believed that the Milky Way was a flat disk with two spiral arms, measurements taken over the past century have revealed an unexplained curvature. The deformation mainly occurs at the edges of the galaxy, where certain regions sink while others curve upwards, giving it a flattened appearance similar to a hat.
Computer simulations carried out by researchers may have uncovered the cause behind this phenomenon. The simulations point to a mysterious event that disrupted the alignment of our galaxy’s invisible halo of dark matter. The study, published in the journal Nature Astronomy on September 14th, provides compelling evidence that our galaxy is enveloped in an inclined halo of dark matter.
Dark matter is an elusive type of matter that constitutes approximately 85% of the total matter in the universe. Although it does not directly interact with light and remains invisible, its gravitational effects can be observed. Dark matter is responsible for accelerating stars to extraordinary speeds as they orbit galactic centers, distorting distant starlight, and shaping the galactic halo of the Milky Way.
The galactic halo refers to a vast sphere of stars that float like leaves in a dark matter pond, located beyond the spiral arms of the Milky Way. Recent research using the European Space Agency’s Gaia spacecraft has shown that the stars within the galactic halo are peculiarly misaligned.
In an attempt to understand the implications of an imbalanced stellar halo for the dark matter halo, astronomers used computer models to recreate a young galaxy similar to the Milky Way. The model included a 25-degree inclined dark matter halo relative to the disk. After simulating the galaxy for 5 billion years, the researchers discovered that their model closely resembled our own galaxy.
The cause behind the misalignment of the dark matter halo is still unclear. However, simulations conducted by the researchers suggest that it is likely the result of a massive collision, potentially involving another galaxy colliding with ours. This collision could have caused the dark matter halo to tilt up to 50 degrees before slowly descending to its current elevation of 20 degrees.
Sources:
– “A massive block of invisible dark matter has deformed our galaxy”
– “Dark matter may be accumulating within dead stars, with potentially explosive consequences”