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Pole Vault Pole

Publicerad: 2025-12-19

My goal in life is to be personally responsible for at least one sports rule change.

My goal in life is to be personally responsible for at least one sports rule change.

Telescope Types

Publicerad: 2025-12-17

I'm trying to buy a gravitational lens for my camera, but I can't tell if the manufacturers are listing comoving focal length or proper focal length.

I'm trying to buy a gravitational lens for my camera, but I can't tell if the manufacturers are listing comoving focal length or proper focal length.

Jumping Frog Radius

Publicerad: 2025-12-15

Earth's r_jf is approximately 1.5 light-days, leading to general relativity's successful prediction that all the frogs in the Solar System should be found collected on the surface of the Earth.

Earth's r_jf is approximately 1.5 light-days, leading to general relativity's successful prediction that all the frogs in the Solar System should be found collected on the surface of the Earth.