Taking the Twinkle Out of Starlight

Shape-changing mirrors are giving astronomers their best views ever. They'll soon include the first sight of a planet in another solar system

13 min read

You're camping out in the mountains on a clear summer night. The velvet-black sky sparkles with millions of flickering dots. The starry twinkle, though, which has driven generations of poets to rapture, is the bane of astronomers bent on capturing clear, sharp images of the galaxies, stars, and planets that populate the universe. Viewed through large Earth-based telescopes, that twinkle is seen as blur, which reduces astronomers' ability to see finely detailed structure. Sir Isaac Newton identified the problem 300 years ago [see "Early Days"]. Writing less than a century after the invention of the telescope, he declared: "If the theory of making Telescopes could at length be fully brought into Practice, yet there would be certain bounds beyond which Telescopes could not perform. For the air through which we look upon the stars is in perpetual Tremor." The "tremor" arises from turbulent mixing of air at different temperatures, which continually changes the speed and direction of starlight as it passes through the atmosphere. The same effect distorts the view of distant objects seen through the shimmer above a hot parking lot.

Today, a new technology called adaptive optics is, in effect, removing the atmospheric tremor. And the improvements that it brings to today's telescopes represent an advance at least as great as the invention of the telescope itself. The technique brings together the latest in computers, material science, electronic detectors, and digital control in a system that warps and bends a mirror in the telescope to counteract, in real time, the atmospheric distortion.

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Engineers Are Working on a Solar Microgrid to Outlast Lunar Nights

Future lunar bases will need power for mining and astronaut survival

4 min read
A rendering of a lunar base. In the foreground are rows of solar panels and behind them are two astronauts standing in front of a glass dome with plants inside.
P. Carril/ESA

The next time humans land on the moon, they intend to stay awhile. For the Artemis program, NASA and its collaborators want to build a sustained presence on the moon, which includes setting up a base where astronauts can live and work.

One of the crucial elements for a functioning lunar base is a power supply. Sandia National Laboratories, a research and development lab that specializes in building microgrids for military bases, is teaming up with NASA to design one that will work on the moon.

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Trilobite-Inspired Camera Boasts Huge Depth of Field

New camera relies on “metalenses” that could be fabricated using a standard CMOS foundry

3 min read
Black and white image showing different white box shapes in rows

Scanning electron microscope image of the titanium oxide nanopillars that make up the metalens. The scale is 500 nanometers (nm).


Inspired by the eyes of extinct trilobites, researchers have created a miniature camera with a record-setting depth of field—the distance over which a camera can produce sharp images in a single photo. Their new study reveals that with the aid of artificial intelligence, their device can simultaneously image objects as near as 3 centimeters and as far away as 1.7 kilometers.

Five hundred million years ago, the oceans teemed with horseshoe-crab-like trilobites. Among the most successful of all early animals, these armored invertebrates lived on Earth for roughly 270 million years before going extinct.

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Take the Lead on Satellite Design Using Digital Engineering

Learn how to accelerate your satellite design process and reduce risk and costs with model-based engineering methods

1 min read

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