TELESCOPE OF THE UNIVERSE

Your special report on “A New Era for Astronomy” includes several photographs from the James Webb Space Telescope (JWST). In one article in the report, “Behind the Pictures,” by Clara Moskowitz and Jen Christiansen, science visuals developer Alyssa Pagan of the Space Telescope Science Institute comments on how scientists turn raw data from the telescope into images that give a truer representation than what our naked eye can see.

I was stunned by these photographs, first by their beauty and second by the six-pointed stars around bright objects. I am guessing the latter are artifacts resulting from the construction of the telescope. I am also guessing the photo-processing software used to make the images includes an option for removing them. Are perhaps the images given to astronomers made with such an option on? What is the truth about those pretty six-pointers?

By the way, the six-pointers provide an easy way to tell a JWST photograph from a Hubble image: publicly available Hubble photographs have four-pointed stars.

THOMAS R. KRAMER via e-mail

The article on the components of JWST was excellent. The marvelous photographs made me feel very small, however—many magnitudes as small as a subatomic particle. It's an old, big universe out there.

MIKE MAFFETT Lake Burton, Ga.

PAGAN REPLIES: Kramer's intuition is right in that these spikes are caused by the construction of the telescope. Technically, there are eight diffraction spikes in total: the prominent six spikes he mentions, which are the result of the light diffracting off the edge of each side of the primary hexagonal mirror, and two smaller horizontal spikes, which are caused by the light interacting with the two struts holding the secondary mirror. How this pattern arises is described further in an infographic entitled “Webb's Diffraction Spikes” that you can find at webbtelescope.org.

As of late, the calibration pipeline has no feature for removing the spikes. This kind of distribution of light from a single-point source is called a point spread function (PSF) and is unique to each optical system. While not infeasible, it is difficult to model and subtract such a complex PSF across an entire image. When the pattern obscures crucial information in a specific target that takes up most of the field, however, the scientists or image processors will go in and manually remove the PSF. Otherwise, we allow JWST to differentiate itself with its eight-spike signature.

NEURODIVERSITY

I found it interesting to read “Rethinking Autism Therapy” [The Science of Health], Claudia Wallis's piece on how autism treatment is moving away from “fixing” the condition. I applaud the approach of allowing people to be who they are and commend the idea that society needs to work harder at accepting neurodiversity. In emphasizing past and current views about attempts to change behaviors, however, the piece may imply that applied behavioral analysis (ABA) is the only therapeutic model available. It seems to ignore therapies such as relationship development intervention (RDI), which allows for more flexibility on the part of the autistic person and those around them while helping them understand more about how social and other situations work, rendering those situations less confusing.

It would be appropriate to have a more balanced look at which autism therapies actually work to the advantage of the person in therapy, not just the perspectives of those who are looking in from the outside.

MIRIAM DUMAN GOLDBERG via e-mail

It is good to see that autism therapists are coming to realize how harmful forcing conformity can be. As a person on the spectrum myself, I hope that this can be communicated to the general population as well. Attempts to force changes in the way of thinking can create depression and quash creativity.

JAMES W. SCOTT Vernon, N.J.

TRAUMA AND EXPERIENCE

In “An Invisible Epidemic,” Elizabeth Svoboda discusses a type of trauma caused by a person's core principles being violated, such as during wartime. This “moral injury” sounds like a way of life for many people. Gay and transgender people have to constantly adjust responses to external cues, circumstances and attacks. Over a long period of time, this can weigh heavily.

If the psychologists mentioned in the article would interview some older gay and trans people, they may find the coping mechanisms and support strategies these individuals have used to be helpful, which could move their own research on treatments forward.

STEVEN CAIN Irving, Tex.

COSMIC QUICK START

Jonathan O'Callaghan's article “Breaking Cosmology” successfully describes JWST's flurry of images of surprisingly early galaxies and possible explanations for them. I also commend the author's brief comments on how the rush to publish these findings suggests a more efficient and faster peer-review process.

JAMES CARLISLE Atascadero, Calif.

According to O'Callaghan, JWST data show early galaxies that seem too large and well developed for their age. I recall other Scientific American articles describing supermassive black holes that also seemed too large for their early times. Which came first? Could precocious supermassive black holes have contributed to the precocious development of galaxies?

K. CYRUS ROBINSON armONx, Tampa Bay, Fla.

The article describes 120 million years as “a cosmic blink of an eye.” This would be 0.87 percent of the universe's age of 13.8 billion years. An eyeblink of 0.1 second is 0.0000000045 percent of three score and 10 years of life. Perhaps “a long winter's nap” might be a closer metaphor.

BILL CIPRA via e-mail

O'CALLAGHAN REPLIES: Robinson asks a good question. The simple answer is that we don't know. We see supermassive black holes at the centers of nearly all large galaxies, but how such black holes formed so early in the universe is an open question. It's unclear whether they formed within already grown galaxies or were instead the seeds of such growth, perhaps created by the collapse of supermassive stars in the early cosmos.

MIND OVER MATTER

“Constructing the World from Inside Out,” by György Buzsáki [June 2022], explores how perception of our physical surroundings occurs in the brain. An even more puzzling question is how the brain constructs worlds that cannot be perceived by the senses, as Plato demonstrated in his dialogue Meno. This was also mysterious to Albert Einstein, who said in a 1921 lecture, “How can it be that mathematics, being after all a product of human thought which is independent of experience, is so admirably appropriate to the objects of reality?”

TONY JOHNSON San Rafael, Calif.

ERRATUM

“Overdose of Inequality,” by Melba Newsome and Gioncarlo Valentine, included an image caption that erroneously referred to physician Edwin Chapman as Edward Chapman. His name was given correctly in the main text.