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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 President’s Note: Looking to 2050 and Beyond

The importance of future-proofing IEEE

4 min read
Photo of K. J. Ray Liu

What will the future of the world look like? Everything in the world evolves. Therefore, IEEE also must evolve, not only to survive but to thrive.

How will people build communities and engage with one another and with IEEE in the future? How will knowledge be acquired? How will content be curated, shared, and accessed? What issues will influence the development of technical standards? How should IEEE be organized to be most impactful?

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The Device That Changed Everything

Transistors are civilization’s invisible infrastructure

2 min read
A triangle of material suspended above a base

This replica of the original point-contact transistor is on display outside IEEE Spectrum’s conference rooms.

Randi Klett

I was roaming around the IEEE Spectrum office a couple of months ago, looking at the display cases the IEEE History Center has installed in the corridor that runs along the conference rooms at 3 Park. They feature photos of illustrious engineers, plaques for IEEE milestones, and a handful of vintage electronics and memorabilia including an original Sony Walkman, an Edison Mazda lightbulb, and an RCA Radiotron vacuum tube. And, to my utter surprise and delight, a replica of the first point-contact transistor invented by John Bardeen, Walter Brittain, and William Shockley 75 years ago this month.

I dashed over to our photography director, Randi Klett, and startled her with my excitement, which, when she saw my discovery, she understood: We needed a picture of that replica, which she expertly shot and now accompanies this column.

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FAST Labs’ Cutting-Edge R&D Gets Ideas to the Field Faster

BAE Systems’ FAST Labs engineers turn breakthrough innovations into real-life impact

1 min read

FAST Labs is an R&D organization where research teams can invent and see their work come to life.

BAE Systems

This is a sponsored article brought to you by BAE Systems.

No one sets out to put together half a puzzle. Similarly, researchers and engineers in the defense industry want to see the whole picture – seeing their innovations make it into the hands of warfighters and commercial customers.

That desire is fueling growth at BAE Systems’ FAST Labs research and development (R&D) organization.

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