Tag Archives: lasers

There’s a reason why stars appear to twinkle and it’s this: constantly moving pockets of slightly off-temperature air in the Earth’s atmosphere that distort the light paths from distant astronomical objects.

But how to counter the blur caused by this atmospheric turbulence? To wit:

The telescope featured in this image, located at ESO’s Paranal Observatory, is equipped with four lasers […] tuned to a colour that excites atoms floating high in Earth’s atmospheresodium left by passing meteors. These glowing sodium spots act as artificial stars whose twinkling is immediately recorded and passed to a flexible mirror that deforms hundreds of times per second, counteracting atmospheric turbulence and resulting in crisper images. The de-twinkling of stars is a developing field of technology and allows, in some cases, Hubbleclass images to be taken from the ground. This technique has also led to spin-off applications in human vision science, where it is used to obtain very sharp images of the retina.

(Image: Juan Carlos Muñoz / ESO; Text: Juan Carlos Muñoz)

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Early compact-disc artwork. As dated as humanly possible, and catalogued by US pop-radio jamboree Crap From The Past (streaming and downloadable weekly).

As soon as CDs were introduced to the US marketplace, a handful of samplers were introduced as a guide to both consumers and retailers. For many, these were the first introduction to digitally-stored sound.

All of these CDs are extremely hard to find today, if you’d be looking for them at all. Most of them were pressed in West Germany, because US facilities weren’t up to speed yet.

Because for all the backlash the vinyl revival may have received, at least it didn’t result in cheap futurism…

Pew pew.

Crap from the Past