When will it be dark?
Our Sun provides light and warmth, sustaining life on Earth, and who doesn't enjoys beautiful sunrise or sunset with its changing colors?
As the rays of the rising or setting Sun travel through more of the Earth’s atmosphere, the violet and blue light waves are scattered. This gives us stunning yellows, oranges and reds... the red lasts the “longest” at sunset because red light has the longest wavelength.
Even when the Sun is below the horizon, its light can block all but the brightest planets and stars. Twilight is the diffused light in the sky during the early evening or early morning, when the sun is below the horizon and its light is refracted by the Earth's atmosphere.
Civil Twilight is when the sun is 6 degrees below the horizon and only the very brightest stars and planets can be seen under good atmospheric conditions.
Nautical Twilight is when the stars really start to appear. It is called "Nautical" because it was when sailors on ships could see enough stars to navigate by them at night.
Astronomical Twilight is when the sky is as dark as it will get. This is the time we want so that we can see the most stars.
Let’s go stargazing!
Go outside to experience the fading light of the Sun and the slow unveiling of the heavens above.
Observe how many stars you can see at each stage of twilight.
The exact time for each of these twilights depends on your latitude / longitude and the time of year. Click the link below to see when it will be dark in Round Rock tonight.