Skip to content

Enjoy unlimited access

Only $2.99 a month

All Topics
- Health
- Humans
- Life
- Earth
- Physics
- Space

Magazine
Menu
About
For Students
Our Store

Donate

Science News

INDEPENDENT JOURNALISM SINCE 1921 SIGN IN

Search

Science News

INDEPENDENT JOURNALISM SINCE 1921

All Topics
- Earth
- Humans
- Life
  - Animals
  - Plants
  - Ecosystems
  - Paleontology
  - Neuroscience
  - Genetics
  - Microbes
- Physics
- Space
- Tech
  - Computing
  - Artificial Intelligence
- Chemistry
- Math
- Science & Society
Health
Humans
- Humans
- Recent posts in Humans
  - Health & Medicine
    AI could transform health care, but will it live up to the hype?
    
    By Meghan Rosen and Tina Hesman SaeyJanuary 10, 2025
  - Humans
    How child soldiers heal after the trauma of war
    
    By Elizabeth QuillJanuary 10, 2025
  - Health & Medicine
    Is alcohol linked to cancer? Here’s what the science says
    
    By Aimee CunninghamJanuary 7, 2025
Life
- Life
  - Animals
  - Plants
  - Ecosystems
  - Paleontology
  - Neuroscience
  - Genetics
  - Microbes
- Recent posts in Life
  - Neuroscience
    How people suppress memories may be key to PTSD recovery
    
    By Laura SandersJanuary 9, 2025
  - Paleontology
    Humans, not climate change, may have wiped out Australia’s giant kangaroos
    
    By Carolyn GramlingJanuary 9, 2025
  - Animals
    More new geckos have been found hiding in Southeast Asia’s limestone towers
    
    By Stefan LovgrenJanuary 8, 2025
Earth
- Earth
- Recent posts in Earth
  - Climate
    2024 was Earth’s hottest year on record, passing a dangerous warming threshold
    
    By Carolyn GramlingJanuary 10, 2025
  - Paleontology
    Humans, not climate change, may have wiped out Australia’s giant kangaroos
    
    By Carolyn GramlingJanuary 9, 2025
  - Climate
    California wildfire season should be over. So why is L.A. burning?
    
    By Nikk OgasaJanuary 8, 2025
Physics
- Physics
- Recent posts in Physics
  - Particle Physics
    Cosmic rays could help reveal how tornadoes form
    
    By Emily ConoverJanuary 8, 2025
  - Particle Physics
    A major new neutrino experiment is nearing completion
    
    By Emily ConoverJanuary 3, 2025
  - Physics
    Fiber friction is the key to cozy knits
    
    By Emily ConoverDecember 23, 2024
Space
- Space
- Recent posts in Space
  - Planetary Science
    Pluto may have captured its moon Charon with a kiss
    
    By Lisa GrossmanJanuary 6, 2025
  - Space
    NASA’s Parker Solar Probe survived its closest approach to the sun
    
    By Lisa GrossmanJanuary 2, 2025
  - Particle Physics
    Scientists are building underwater neutrino telescopes in the Mediterranean
    
    By Emily ConoverDecember 23, 2024

Feature

Greater Accuracy Gained in Optical Flats

Share this:

Email
Facebook
Twitter
Pinterest
Pocket
Reddit
Print

By Science News

Magazine Issue: Vol. 71 No. #16, April 20, 1957

Having trouble viewing this? Open in a new window

Share this:

Email
Facebook
Twitter
Pinterest
Pocket
Reddit
Print

Questions or comments on this article? E-mail us at feedback@sciencenews.org | Reprints FAQ

A version of this article appears in the April 20, 1957 issue of Science News.

We are at a critical time and supporting climate journalism is more important than ever. Science News and our parent organization, the Society for Science, need your help to strengthen environmental literacy and ensure that our response to climate change is informed by science.

Please subscribe to Science News and add $16 to expand science literacy and understanding.

Related Stories

Readers react to Betelgeuse’s buddy, the 2024 Nobels and small nuclear reactor waste

By Science News Staff12 hours ago
Enter a new era for our storied magazine

By Nancy Shute12 hours ago
Climate
2024 was Earth’s hottest year on record, passing a dangerous warming threshold

By Carolyn GramlingJanuary 10, 2025

Science News

Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).

Science News Explores
Science News Learning

Subscriber Services

Subscribe
Renew
Give a Gift Subscription
Customer Service

Follow Science News on Facebook
Follow Science News on X
Follow Science News via RSS
Follow Science News on Instagram
Follow Science News on YouTube
Follow Science News on TikTok

More Information

FAQ
Newsletters
Rights & Permissions
Advertise
Contact

Society for Science

About the Society
Society Store
Donate
Careers

© Society for Science & the Public 2000–2025. All rights reserved.

1719 N Street, N.W., Washington, D.C. 20036 202.785.2255

Terms of Service Privacy Policy

Log in

Subscribers, enter your e-mail address for full access to the Science News archives and digital editions.

Not a subscriber?
Become one now.

Client key* E-mail Address*