Viewing images goes along with the job for Hospital of Central Connecticut interventional radiologist Dr. Robert Gendler. But the images he’s been working with at night are truly galactic, with his latest subject more than two million light years away.
Also an astrophotographer, Gendler was commissioned to produce an image selected by NASA to help celebrate the 25th anniversary of the Hubble space telescope, launched in 1990.
The assembled image, recorded by Hubble from 2010 to 2013, covers one-third of the spiral-shaped Andromeda Galaxy and fully visualizes over 100 million stars. With more than 400 panels (7,398 exposures), it is the largest Hubble image ever produced. It was publicly released Jan. 5 at the Annual Meeting of the American Astronomical Society in Seattle.
Gendler, whose fifth book related to astrophotography will be published this year, was approached last spring by the University of Washington Astronomy Department to create the image. Both NASA and the Space Telescope Science Institute, which manages the Hubble, supported the request. “It was a big honor for me to be asked to make an image for NASA, and especially one of this importance,” he says.
As the Hubble is above the atmosphere, Gendler says it produces the highest resolution images of any telescope. Its primary objective is research; the Hubble sends images of our universe as it orbits the earth.
The approximately nine-gigabyte image Gendler produced is sprinkled with many colors, which Gendler says represent the signatures of star birth and other cosmic processes.
While the image is striking, Gendler notes it “wasn’t just taken to produce a nice, pretty picture; it was assembled primarily for research purposes.” He says the image is a “treasure chest of data astronomers can use for years and years to come.
“This was a very challenging project because it involved an enormous amount of data that had to be spliced together with a high degree of precision so that the colors and the contrasts and the brightness all matched so in the end we have a single coherent image with accurate color; and it’s the most detailed image of the Andromeda Galaxy ever produced,” Gendler says. The Andromeda Galaxy, the closest to our own Milky Way Galaxy, is about 2.5 million light years away; one light year is more than 5 trillion miles.
Image data were recorded using Hubble’s Advanced Camera for Surveys and Wide Field Camera 3. It took Gendler a few months to assemble the image. “It was literally thousands of sub exposures that needed to be spliced together,” he says. Those sub exposures morphed into about 400 panels he then assembled like a puzzle.
The recorded data, known as part of the PHAT (Panchromatic Hubble Adndromeda Treasury) project and the final image “helps us because we learn about another galaxy in high detail – how did the Andromeda Galaxy form? Is it made up of similar stars as the Milky Way? The Milky Way is our local galaxy so we can study those stars much more easily without the help of Hubble,” he says.
Since childhood Gendler has had a fascination with astronomy, inspired as a boy by going on school trips to the Hayden Planetarium in Manhattan. He coupled that interest with photography, taking after his father, a retired professional photographer. Gendler would later add a camera to the back of a telescope to become an astrophotographer. His photographs of the night sky have even crossed over into the hospital’s New Britain General campus where more than 30 of his stellar photos hang in its hallways and Radiology reception area, presenting patients, staff and visitors with a colorful twinkle of the cosmic sky.
But this latest image, he says is “one of the most challenging images I’ve ever made.”
More of Gendler’s work can be seen on his website www.robgendlerastropics.com.