When it comes to spherical perfection, nothing we’ve ever discovered in space beats Kepler-11145123, the roundest object in the world. This distant star is located about 5,000 light-years away from Earth.
What Defines “Round”?
Before diving into Kepler-11145123, it’s essential to understand what we mean by “round.” Most celestial objects take on a somewhat spherical shape due to the gravitational forces pulling matter toward their centers. However, the force of their rotation tends to squash them at the poles and widen them at the equator, causing an oblate spheroid shape. The difference between the equatorial and polar diameters of a celestial body measures its “roundness.”
Kepler-11145123 was initially discovered as part of NASA’s Kepler mission, designed to find exoplanets by observing stars and the tiny dimming caused by planets passing in front of them. While that was Kepler’s primary task, its trove of data fueled other groundbreaking research as well. Researchers from the Max Planck Institute for Solar System Research in Germany used these precise observations to study the star’s oscillations, which provided clues about its internal structure and, fascinatingly, its shape.
A Surprising Level of Perfection
What truly sets Kepler-11145123 apart is the astonishingly small difference between its equatorial and polar diameters. The star’s equatorial diameter exceeds its polar diameter by a mere 3 km, despite having a diameter of 1.5 million km overall. This difference is microscopic on a cosmic scale and represents an unprecedented level of spherical perfection. For context, the disparity between the Earth’s equatorial and polar diameters is about 42 km, a figure that suddenly feels gigantic compared to this distant star.
The Science Behind the Shape
Kepler-11145123’s almost-perfect roundness is intriguing and prompts the question: how did it get so round? One leading hypothesis is that magnetic fields within the star could be redistributing mass, making it more spherical. However, researchers also point out that the star’s slow rotation rate plays a significant role. The slower an object rotates, the less it gets flattened due to centrifugal forces. Kepler-11145123 spins at a much slower rate than our Sun, thus maintaining its almost perfect shape.
Broader Implications of Being the Roundest Object in the World
The discovery of Kepler-11145123’s unique shape has broader implications for our understanding of astrophysics. It forces scientists to reevaluate models of star evolution, as well as the role magnetic fields play in shaping celestial bodies. Furthermore, this finding might have implications for exoplanet studies. A star’s shape can influence the stability of its planetary orbits, which in turn could have consequences for planetary climates and habitability.
Why Should We Care About the Roundest Object in the World?
Apart from the sheer wonder of discovering such a perfectly round object in space, understanding Kepler-11145123 can help scientists refine their models of stellar behavior and evolution. These models are fundamental to our grasp of the universe, from the life cycles of stars to the forces that shape galaxies. The more accurate our models become, the better we can understand a host of other phenomena, including potentially habitable exoplanets.
Source: “Distant star Kepler 11145123 is the roundest object ever observed in nature” — Astronomy Now