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Read about star travel via conventional propulsion, warp drives, and more.
Red rainbows happen when the sun is on the horizon. They’re created in much the same process that causes a sunset or sunrise to look red.
As Earth spins under the sky, the stars appear to move. When a camera captures that movement, that’s called a star trail. Plus … an astrophotographer explains how he does it.
A rainbow isn’t a flat two-dimensional image on the dome of sky. It’s more like a mosaic, composed of many separate bits … in three dimensions.
That glow over the unlit part of a crescent moon – called earthshine – is light reflected from Earth.
Sun pillars, or light pillars, are shafts of light extending from the sun or other bright light source. They’re caused by ice crystals drifting in Earth’s air.
What are the Ides of March? We in modern times probably wouldn’t know, if it weren’t for William Shakespeare.
A star’s luminosity is its true brightness. Nearly every star you see with the unaided eye is more luminous than our sun.
It’s sometimes said that, on a worldwide scale, solar eclipses outnumber lunar eclipses by about a three to two margin. True?
This year, in 2016, there are 12 full moons and 13 new moons, but only four eclipses – two solar and two lunar.
Planet Uranus in moon glare December 9
Moon halo and 2 planets