S27E73: Dark Matter Mysteries and Martian Lake Myths Debunked

Join us for SpaceTime Series 27 Episode 73, where we delve into the latest cosmic discoveries and advancements shaping our understanding of the universe.
First, astronomers have developed a new theory of dark matter to explain the mysterious dwarf galaxy Crater 2. Despite its proximity at 383,000 light-years from Earth and its large size-making it the fourth largest satellite galaxy orbiting the Milky Way-Crater 2 has a surprisingly low surface brightness and velocity dispersion. This has led scientists to propose the self-interacting dark matter (SIDM) theory, which may better account for the galaxy's unusual properties.
Next, new research dismisses the idea of a lake under the Martian south polar ice cap. Instead, it suggests that the bright radar reflections previously interpreted as liquid water are likely due to resolution interference between radio waves. This finding, based on computer simulations, challenges the notion of subsurface liquid water on Mars.
Finally, we highlight the development of a new daytime optical telescope, the Huntsman, which allows astronomers to observe celestial objects even when the sun is high overhead. This groundbreaking instrument, located at Siding Spring Observatory, uses an array of camera lenses designed for ultra-sensitive night sky observations but can also accurately measure stars and satellites during daylight.
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[@shawns0762]

The fundamental phenomenon of dilation (sometimes called gamma or y) explains galaxy rotation curves/dark matter. Mass that is dilated is smeared through spacetime relative to an outside observer. It's the phenomenon behind the phrase "mass becomes infinite at the speed of light". A 2 axis graph illustrates the squared nature of the phenomenon, dilation increases at an exponential rate the closer you get to the speed of light. A time dilation graph illustrates the same phenomenon, it's not just time that gets dilated.
Dilation will occur wherever there is an astronomical quantity of mass because high mass means high momentum. This includes the centers of very high mass stars and the overwhelming majority of galaxy centers.
It can be inferred mathematically that the mass at the center of our own galaxy is dilated. This means that there is no valid XYZ coordinate we can attribute to it, you can't point your finger at something that is smeared through spacetime. More precisely, everywhere you point is equally valid. In other words, that mass is all around us.
Dilation does not occur in galaxies with low mass centers because they do not have enough mass to achieve relativistic velocities. It has been confirmed in 6 very low mass galaxies including NGC 1052-DF2 and DF4 to have no dark matter, in other words they have normal rotation rates.