What's a scary science fact that the public knows nothing about?

Scientific literature's conclusion on Alzheimer's disease and other neurodegenerative diseases in general

is that the diseases start decades before the first obvious symptoms and that we need to treat them at this stage.

When you exhibit obvious symptoms, it's too late and your brain is already

mush. If you get diagnosed with Alzheimer's at 65, you've had the disease since your early

40s at least, and you experienced very mild symptoms but didn't notice it. And your brain

fought like hell to compensate for the deficit. When you get diagnosed, your brain is already

severely damaged and will never recover from the deficit.

There's a gravitational anomaly in space called the Great Attractor, which is pulling everything within the Virgo and Hydrus and Taurus superclusters towards it.

It lies 150 to 250 million light years from the Milky Way, which itself is being pulled towards it too.

The scary part is that relative to us, this anomaly lies within the same plane as our own galaxy,

making it very difficult to observe. Essentially, we have almost no concrete idea of what it is.

On the flip side of the great attractor is the Boaties void, which I find a bit creepy.

The Boaties void, sometimes called the Great Void, is a huge spherical region of space that contains very few galaxies.

It's approximately 700 million light years from Earth, and located near the constellation Boaties, which is how it got its name.

The Super Void measures 250 million light

years in diameter, representing approximately 0.27% of the diameter of the observable universe,

which itself is a daunting 93 billion light years across. Its volume is estimated at 23,000

megaparsecs cubed, making it the largest known void in the universe.

At first, astronomers were only able to find eight galaxies across the expanse, but further

observations revealed a total of 60 galaxies.

Now, while that might still seem like a lot, it would be like stumbling upon only 60 objects

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