Space palettes
The James Webb Space Telescope’s first images offer the most detailed and clearest view yet of outer space. Lisa Grossman reported in “Postcards using a new space telescope” (SN: 8/13/22, p. 30).
JWST uses infrared light to observe space. This is a type of light that is not visible to the eye. Scientists colorize the images to make them more visible. Reader John Dohrmann Wondering how this colorizing works?
JWST’s images are colorized by senior data imaging developer Joseph DePasquale and science visuals developer Alyssa Pagan, both of the Space Telescope Science Institute in Baltimore, Grossman says. The basic rule is to use wavelengths of light to guide the painting. According to her, the color red is determined by the wavelength of light that was emitted from the image. The color blue is assigned for the shorter wavelength. Wavelengths in the middle are A spectrum of yellows and greens was assigned (SN: 3/17/18, p. 4). There are other factors to consider, like data about the chemical composition of the elements in the image. It can be more art than science to colorize these elements. Grossman says. “There’s a subjective artistry to it too.”
Reader Stu Kantor asked why some stars in the JWST images appear to have eight spikes — six large ones and two smaller ones (see “Out of this world,” below).
These are known as diffraction peaks. Grossman says, and they’re an artifact of the telescope’s optical setup. JWST has two mirrors. One is a primary hexagonal mirror, and the other is smaller and sits in front. It is held up by three support beams. When it hits the telescope, light bends at the two edges of each of the secondary mirror’s supports, producing six diffraction spikes. Six spikes are also created by the six edges of primary mirror. Scientists designed the telescope so that four of the spikes from the secondary supports overlap with four of the primary mirror’s spikes, GrossmanSo, although there are twelve spikes we see only eight.
JWST is not the only place that has diffraction spikes. “Images from the Hubble Space Telescope have these too, but they only have four,” Grossman says. “The eight points are a distinctive feature of JWST, like an artist’s signature.”
On the nose
Scientists discovered a neural link in the dog brain that connects the olfactory system to vision, which may help explain why humankind’s best friend is such a good sniffer, Laura Sanders reported in “New nose-to-brain link ID’d in dogs” (SN: 8/13/22, p. 9).
Many people were moved by the story and began to consider how their furry friends behave.
“I now know why my German shepherd could not play the simplest version of the shell game,” Ed Hughes wrote. “Using a small piece of dog food and two Dixie cups … one shift in the location of the cup hiding the dog food completely confused her. Her eyes followed the cup but she didn’t pick the cup with the dog foods. She had prelocated it with her nose, and anything her eyes detected was completely ignored.”
Reader Roy R. Ferguson shared his fascination with dogs’ sniffing abilities, having worked with the animals in search and rescue efforts for the last 20 years with his wife.
“We have learned to allow the K-9s to do their work with as little supervision as possible,” Ferguson wrote. “They constantly make decisions that seem unusual at the time but make sense once the full story is known.”
“Our K-9s have located drops of blood in light rain and human decomposition in various vehicles. Live finds include one man who wandered over 10 miles after a head wound and a 6-year-old who had been out all night …. The child find was notable due to the large amount of scent contamination in the area,” Ferguson added.
“We have no idea how these amazing creatures do such marvelous feats. They work their hearts out for nothing more than praise and a toy reward,” Ferguson wrote. “It has occurred to [us]We are there to support them, drive the radio and help them. In return, they make us look as though we know what we’re doing.”
