Readers discuss colors and spikes in the James Webb Space Telescope’s images and more

House palettes

The beautiful first photos from the James Webb House Telescope present the deepest and clearest look but into outer house, Lisa Grossman reported in “Postcards from a new space telescope” (SN: 8/13/22, p. 30).

JWST observes house utilizing infrared, a type of mild not seen to the human eye. To visualise the pictures, scientists colorize them. Reader John Dohrmann puzzled how that colorizing is finished.

JWST’s pictures are colorized by senior information imaging developer Joseph DePasquale and science visuals developer Alyssa Pagan, each of the House Telescope Science Institute in Baltimore, Grossman says. Their primary rule of thumb is to color the photographs utilizing wavelengths of sunshine as a information. The sunshine emitted within the longest wavelength in a picture is assigned the colour crimson, and the shortest blue, she says. Wavelengths in between are assigned a spectrum of greens and yellows (SN: 3/17/18, p. 4). However there are additionally different concerns, comparable to information on the chemical compositions of stuff within the picture. How one can colorize these parts will be extra of an artwork than a science, Grossman says. “There’s a subjective artistry to it too.”

Reader Stu Kantor requested why some stars within the JWST pictures seem to have eight spikes — six giant ones and two smaller ones (see “Out of this world,” beneath).

These are referred to as diffraction spikes, Grossman says, they usually’re an artifact of the telescope’s optical setup. JWST has two mirrors: a major hexagonal mirror and a smaller secondary mirror that sits in entrance of the first mirror and is held up by three help beams. When it hits the telescope, mild bends on the two edges of every of the secondary mirror’s helps, producing six diffraction spikes. The six edges of the first mirror additionally create six spikes. Scientists designed the telescope in order that 4 of the spikes from the secondary helps overlap with 4 of the first mirror’s spikes, Grossman says, so although there are 12 spikes, we see solely eight.

Diffraction spikes should not distinctive to JWST. “Photos from the Hubble House Telescope have these too, however they solely have 4,” Grossman says. “The eight factors are a particular characteristic of JWST, like an artist’s signature.”

On the nostril

Scientists found a neural hyperlink within the canine mind that connects the olfactory system to imaginative and prescient, which can assist clarify why humankind’s greatest buddy is such an excellent sniffer, Laura Sanders reported in “New nose-to-brain link ID’d in dogs” (SN: 8/13/22, p. 9).

The story impressed a number of readers to mirror on the conduct of their very own furry mates.

“I now know why my German shepherd couldn’t play the best model of the shell sport,” Ed Hughes wrote. “Utilizing a small piece of pet food and two Dixie cups … one shift within the location of the cup hiding the pet food utterly confused her. I might watch her eyes observe the cup, however she by no means picked the cup with the pet food. She had prelocated it together with her nostril, and something her eyes detected was utterly ignored.”

Reader Roy R. Ferguson shared his fascination with canine’ sniffing skills, having labored with the animals in search and rescue efforts for the final 20 years together with his spouse.

“We’ve got realized to permit the Okay-9s to do their work with as little tremendous​imaginative and prescient as attainable,” Ferguson wrote. “They always make selections that appear uncommon on the time however make sense as soon as the total story is understood.”

“Our Okay-9s have positioned drops of blood in mild rain and human decomposition in varied automobiles. Reside finds embrace one man who wandered over 10 miles after a head wound and a 6-year-old who had been out all evening …. The kid discover was notable as a result of great amount of scent contamination within the space,” Ferguson added.

“We don’t know how these superb creatures do such marvelous feats. They work their hearts out for nothing greater than reward and a toy reward,” Ferguson wrote. “It has occurred to [us] that we’re there to supply them help, drive and work the radio. In return, they make us look as if we all know what we’re doing.”

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