Based on xkcd Loves the Discovery Channel
Daily Archives: October 24, 2009
Everything Looks Worse in Black and White
Cocktail Party Physics: images from supernovae to supermodels
Light can be modeled as photons, which are characterized by a wavelength λ and a frequency f. Those quantities are connected by the speed at which the wave travels (which, for electromagnetic waves, is the speed of light). c = f λ, which means that the wavelength decreases as the frequency increases.
Even though humans can see only a very small portion of the electromagnetic spectrum, we are somewhat obsessed about transforming what we see into a format that allows us to share it with other people, or putting it in giant piles in the back of a closet that we really do intend to organize someday. Really.
Was the Moon Adopted?
Controversial Moon Origin Theory Rewrites History
If a new twist on a decades-old theory is right, conditions in the early solar system suggest the moon formed inside Mercury’s orbit and migrated out until it was roped into orbit around Earth.
The idea flies in the face of scientific consensus, known as the giant impact hypothesis, which holds that the moon formed from red-hot debris left over after a Mars-sized object collided with Earth around 4.5 billion years ago.
It’s too generous to call this a theory, as they do in the article. From the scant information, it sounds more like a plausibility argument; physics does not preclude the scenario, so it could have happened. But the next step is looking to see if this could be falsified by what we know or could investigate. It’s not clear to what extent this has already taken place.