The James Webb Space Telescope was launched on Christmas Day, 2021. In January, it arrived at what is planned to be its permanent, high-orbit location about 930,000 miles from Earth. Quickly, it began sending to Earth astonishing images of the Milky Way and surrounding and far-off galaxies. Seeing and recording light emitted billions of years ago, it lets us peer all the way back towards the beginning of time.
There have been a flurry of books and calendars about JWST since 2022. The year 2024 alone has witnessed the publication of at least five major books as well as countless very small-press and self-published books and a truckload of wall calendars. This is possible because all JWST images are in the public domain — as are NASA images in general as long as they don’t include the NASA logo or imply NASA endorsement of a commercial product. Certainly, from book to book and from calendar to calendar, the text accompanying NASA images varies in quality depending on the skill and knowledge of various authors. Fortunately, the authors of National Geographic’s October 2024 Infinite Cosmos: Visions from the James Webb Space Telescope are, if you’ll excuse the expression, stellar.
I say “authors” because, while astrophysicist Ethan Siegel is credited as sole author, string theorist Brian Greene is given prominent credit for the extensive Introduction. One of Greene’s many gifts as a writer is that he anticipates and speaks directly to readers’ curiosity and does not forget the science naifs are inquisitive, too. His words transmit excitement for his subject matter , and I (for one) never fail to thrill at the reading.
As Greene explains matters, the light transmitting the pictures JWST captures is gathered by the telescope’s primary mirror. With a diameter of 6.5 meters, it is about 2.7 times larger than that of the Hubble, JWST’s low-orbit, 1990 predecessor. The larger mirror size is necessary because of one of JWST’s best tricks —seeing through normally impenetrable dust. Hubble has never been able to do that. Its vision is limited to the ultraviolet, visible, and near infrared spectra. JWST is optimized for near- and mid-infrared light. This renders the thick streaks of dust hampering Hubble’s vision transparent.
Greene’s Introduction explains that collecting low-wavelength, infrared information requires significant mirror real estate (hence the larger mirror). Together, the mirror size, the telescope’s high orbit, and the ability to see infrared light allow JWST to peer farther into the universe (a/k/a farther back in time) than ever before. Gracefully and briefly for science naifs, Greene elucidates the characteristics of light in general and of low-wavelength infrared light in particular. His is an impressively succinct approach to deep-information storytelling. He also employs it when writing about star and planetary formation, the evolution of galaxies, and the history and probable future of the universe. The result is an Introduction that gives readers a potentially overwhelming amount of information without inflicting a panic response in them. Readers can stretch to understand without hurting their necks doing so.
Astrophysicist Ethan Siegel is credited as the book’s author. In an enormous middle section of the Infinite Cosmos, he closely recounts JWST’s design challenges and construction. This largest part of the book details the mechanics of JWST’s mirror, sun shield, guidance sensor, and cooling technologies as well as the effort necessary to transport and then launch and monitor JWST. The pictures in this section (they feature men and women in the sort of clothing viewers saw in the spaceship landing-pad scene of the movie ET) give prominence to machinery and tools piled around football field-length clean rooms that (thank goodness) haven’t been styled by set dressers. “People hard at work” images like these are not awe-inspiring in the manner of the images transmitted by JWST. They do, however, make explicit the effort, resources, and precision necessary to provide a flabbergasting extension of knowledge about the universe.
Infinite Cosmos is an almost irresistible coffee table book. Readers: if you’re occasionally mesmerized by the beauty of the night sky, I urge you to shake off any trepidation you have about reading physics. Yes, there’s lots of it here. G’wan. Swim into this book and enjoy learning.
