Optics

Binoculars and other far-range optics span a gamut of price points. Here’s what separates top-tier from entry-level

How big would a telescope need to be to see Earth’s dinosaurs from 66 million light-years away? Think big—and then think bigger

Stars emit lots of green light, but our eyes don’t let us see them that way

In our topsy-turvy universe, sometimes the farther away an object is, the bigger it seems to be

Bizarre phenomena called light echoes create strange, shifting shapes seen in some telescopic images and help astronomers chart the heavens above

An attosecond—or 0.000000000000000001 second—is no time at all for a person. That is not so for electrons, atoms and molecules, and laser-wielding scientists are revealing the action

Telescopes in space give us a view we literally cannot get from the ground

The quirks of light moving through gas are the cause of stellar twinkling, which can be a bane—and sometimes a boon—for astronomers

In colorful photographs of galaxies, stars, planets, and more, what you see isn’t necessarily what you get

With radio and infrared telescopes, astronomers can pierce the dusty veil of our galaxy and map its farthest reaches

Barnard 68 is often mistaken for a hole in space, but it’s actually a dense, opaque cloud of dust—for now

“Twilight rays” are but one of several viewing treats for the liminal time between day and night