moonrise moonset

instagram

Really neat editing of a crescent moon setting over Los Angeles - the moon is so thin that you can see a faint pattern of the rest of the moon’s face. The Moon is actually showing up due to Earthshine - light reflected off the Earth! The other dancing lights are planes

10

Why The Sky Is Blue, According To Science

“The fact that light of different wavelengths respond differently to interactions with matter prove extremely important and useful in our daily lives. The large holes in your microwave allow short-wavelength visible light in-and-out, but keep longer-wavelength microwave light in, reflecting it. The thin coatings on your sunglasses reflect ultraviolet, violet, and blue light, but allow the longer-wavelength greens, yellows, oranges, and reds to pass through. And the tiny, invisible particles that make up our atmosphere — molecules like nitrogen, oxygen, water, carbon dioxide, as well as argon atoms — all scatter light of all wavelengths, but scatter the shorter-wavelength light much more efficiently.”

There are all sorts of explanations that people give for why the sky is blue. Some say that it’s because of the fact that oxygen is a light blue gas. Others contend that the sky reflects the blue ocean, giving it a comparably blue color. Still others place the blame on sunlight itself, alleging that it’s naturally slightly blue in color. All of these science-y sounding explanations, compelling though they might be, are way off the mark. If they were correct, after all, you wouldn’t have reds during sunrise and sunset! Instead, it’s a combination of three factors that make the sky blue for us:

  1. Sunlight is made of many different wavelengths of light.
  2. The small atmospheric molecules scatter that light, but scatter short-wavelength light more efficiently.
  3. And the human eye has three types of cone (and one type of rod) that allow our brains to interpret color.

Put them all together, and a blue sky is the net, inevitable result.

If you’ve ever wondered why the sky is blue, and why it appears different colors in so many different situations, this is the explanation you’ve been looking for!

instagram

muftix Time for another collection of timelapses. The Moon! 🌒
Once again shot in LA, France and New Zealand
.

8

Ask Ethan: Why Doesn’t Earth’s Atmosphere Turn Sunlight Into Rainbows?

“I wondered why white light passing through the Earth’s atmosphere doesn’t separate into the colours of the rainbow. Is it because air is too diffuse and there is insufficient distance of travel when the sun is overhead? When the sun is close to the horizon, so that there is a greater distance to be traversed, it appears to be red. Would the other colours be visible from increasing altitude of the observer?”

There are many impressive optical phenomena that we can see with our own eyes here on Earth. The right configuration of raindrops or ice crystals can produce rainbows, shining light through a prism will separate it into its individual wavelengths, and from high altitudes in the pre-sunrise or post-sunset skies, a full spectrum of colors become visible. Yet despite the beauty and similarities of these phenomena, they don’t arise from the same physics. While ice, water, glass or acrylic will slow down light to anywhere from 66% to 76% of its vacuum speed, air itself will only knock it down to 99.97% of its initial value. In fact, you have to look extremely hard – and under ideal conditions – to see any evidence of atmospheric refraction at all.

Why doesn’t our atmosphere turn sunlight into rainbows? And how does the blue day sky and the red sunset/sunrise sky work? Find out on this week’s Ask Ethan!

I want religious vampires

Catholic vampires who take communion instead of drinking blood

Jewish vampires who are rabbis and have hours-long discussions about whether it’s acceptable to drink blood and, if so, how much

Buddhist vampires who get upset when people say they’re immortal because all dharmas are marked by impermanence

Protestant vampires who refuse to take communion instead of blood because the wine is a symbol

Muslim vampires who abstain from moonrise to moonset on Ramadan

Neopagan vampires who get into fights with pre-Christian pagan vampires over how to worship their gods

Make me immortal.” I asked the gods one day, with ignorance of the thing I asked of them. I simply wished to see beyond my own days and see my great-granddaughters and their daughters.
“Make me immortal.” They did not need more asking. I did not feel any different but they said it was done.
It was many age before I asked for anything again.
“End me.” What I had welcomed with relish and hope, had turned to rot in my mouth. The days passed like leaves in the changing of the seasons.
“End this.” Sunrise, sunset, moonrise, moonset, seasons came and went and people. People just kept dying. What I had asked for had been granted but I had no idea the price I would pay for my wish. The pain of seeing so many years pass without my own end.
Little did I realize I would see the end of the gods themselves in the minds of their people. Of course, the stories were there and still passed on but the power of the gods was lost as mere fables.
“Make me mortal.
—  Thoughts on Immortality - l.h.