Register for an account

X

Enter your name and email address below.

Your email address is used to log in and will not be shared or sold. Read our privacy policy.

X

Website access code

Enter your access code into the form field below.

If you are a Zinio, Nook, Kindle, Apple, or Google Play subscriber, you can enter your website access code to gain subscriber access. Your website access code is located in the upper right corner of the Table of Contents page of your digital edition.

The Sciences

Cosmic Eye Exam Shows Jaw-Dropping Accuracy of Webb Telescope's Optics

The scope's main mirror must hold its shape even down to temperatures near absolute zero.

jwst.jpg

Newsletter

Sign up for our email newsletter for the latest science news

THE MOMENT NASA engineer Ernie Wright examines 6 of the 18 segments of the James Webb Space Telescope’s primary mirror in preparation for a final round of testing at Marshall Space Flight Center in Huntsville, Alabama. A laser system called an interferometer measures how the mirrors warp as they cool from room temperature to –415 degrees Fahrenheit, slightly below their normal operating range in space. The mirrors must hold their shape to within 25 billionths of a meter to perform properly.

THE SHOT Photographer David Higginbotham set remote flashes in front of himself and Wright to light the chamber. He held his Nikon D3 a bit above his eyes so the camera would not appear in the mirrors. The texture seen in the mirrors is the magnified reflection of a seam on Higginbotham’s clean-room suit.

3 Free Articles Left

Want it all? Get unlimited access when you subscribe.

Subscribe

Already a subscriber? Register or Log In

Want unlimited access?

Subscribe today and save 70%

Subscribe

Already a subscriber? Register or Log In