Due to the lapse in federal government funding, NASA is not updating this website.

Suggested Searches

1 min read

Webb’s Diffraction Spikes

Diagram titled “Webb’s Diffraction Spikes” which include five sections that explain facets of diffraction spikes. The first section explains that, in Webb, diffraction spikes are patterns produced as light interacts with the primary mirror and struts that support the secondary mirror. The second section provides examples of diffraction spikes from Hubble and Webb, and explains that diffraction occurs when light waves meet and interact with each other. The third section explains the influence of the primary mirror, according to its shape and number of edges. The fourth section describes the influence of the struts and explains that, when light hits a strut, the light bends into a line perpendicular to the strut. The last section provides a graphical example of the strut and primary mirror influence by using a real star with Webb’s diffraction pattern, with yellow and red outlines. The yellow parts represent the primary mirror influence, while the red parts represent the strut influence.

This illustration demonstrates the science behind Webb’s diffraction spike patterns, showing how diffraction spikes happen, the influence of the primary mirror and struts, and the contributions of each to Webb’s diffraction spikes.

  • Release Date
    July 7, 2022
  • Credit
    Illustration: NASA, ESA, CSA, Leah Hustak (STScI), Joseph DePasquale (STScI)

Downloads

  • Full Res (For Print), 1500 × 7297
    tif (8.11 MB)
  • Full Res (For Display), 1500 × 7297
    png (1.88 MB)
  • Half Res, 750 × 3649
    png (1.11 MB)

Share

Details

Last Updated
Aug 28, 2025
Contact
Media

Laura Betz
NASA’s Goddard Space Flight Center
Greenbelt, Maryland
laura.e.betz@nasa.gov

Illustration Credit

NASA, ESA, CSA, Leah Hustak (STScI), Joseph DePasquale (STScI)