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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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IEEE Medal of Honor Goes to Vint Cerf

He codesigned the Internet protocol and transmission control protocol

2 min read
Photo of a man with a white beard in a dark suit.
The Royal Society

IEEE Life Fellow Vinton “Vint” Cerf, widely known as the “Father of the Internet,” is the recipient of the 2023 IEEE Medal of Honor. He is being recognized “for co-creating the Internet architecture and providing sustained leadership in its phenomenal growth in becoming society’s critical infrastructure.”

The IEEE Foundation sponsors the annual award.

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Fine-Tuning the Factory: Simulation App Helps Optimize Additive Manufacturing Facility

Additive manufacturing processes can provide rapid and customizable production of high-quality components

7 min read
Fine-Tuning the Factory: Simulation App Helps Optimize Additive Manufacturing Facility

An example of a part produced through the metal powder bed fusion process.

This sponsored article is brought to you by COMSOL.

History teaches that the Industrial Revolution began in England in the mid-18th century. While that era of sooty foundries and mills is long past, manufacturing remains essential — and challenging. One promising way to meet modern industrial challenges is by using additive manufacturing (AM) processes, such as powder bed fusion and other emerging techniques. To fulfill its promise of rapid, precise, and customizable production, AM demands more than just a retooling of factory equipment; it also calls for new approaches to factory operation and management.

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