NASA's Fermi Mission Energizes the Sky With Gamma-ray Constellations
The new constellations include a few characters from modern myths. Among them are the Little Prince, the time-warping TARDIS from "Doctor Who," Godzilla and his heat ray, the antimatter-powered U.S.S. Enterprise from "Star Trek: The Original Series" and the Hulk, the product of a gamma-ray experiment gone awry.
"Developing these unofficial constellations was a fun way to highlight a decade of Fermi's accomplishments," said Julie McEnery, the Fermi project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "One way or another, all of the gamma-ray constellations have a tie-in to Fermi science."
Since July 2008, Fermi's Large Area Telescope (LAT) has been scanning the entire sky each day, mapping and measuring sources of gamma rays, the highest-energy light in the universe. The emission may come from pulsars, nova outbursts, the debris of supernova explosions and giant gamma-ray bubbles located in our own galaxy, or supermassive black holes and gamma-ray bursts - the most powerful explosions in the cosmos - in others.
"By 2015, the number of different sources mapped by Fermi's LAT had expanded to about 3,000 - 10 times the number known before the mission," said Goddard's Elizabeth Ferrara, who led the constellation project. "For the first time ever, the number of known gamma-ray sources was comparable to the number of bright stars, so we thought a new set of constellations was a great way to illustrate the point."
The 21 gamma-ray constellations include famous landmarks - such as Sweden's recovered warship, Vasa, the Washington Monument and Mount Fuji in Japan - in countries contributing to Fermi science. Others represent scientific ideas or tools, from Schrodinger's Cat - both alive and dead, thanks to quantum physics - to Albert Einstein, Radio Telescope and Black Widow Spider, the namesake of a class of pulsars that evaporate their unfortunate companion stars.
Ferrara and Daniel Kocevski, an astrophysicist now at NASA's Marshall Space Flight Center in Huntsville, Alabama, developed a web-based interactive to showcase the constellations, with artwork from Aurore Simonnet, an illustrator at Sonoma State University in Rohnert Park, California, and a map of the whole gamma-ray sky from Fermi. Clicking on a constellation turns on its artwork and name, which includes a link to a page with more information. Other controls switch on the visible sky and selected traditional constellations.
"Fermi is still going strong, and we are now preparing a new all-sky LAT catalog," said Jean Ballet, a Fermi team member at the French Atomic Energy Commission in Saclay. "This will add about 2,000 sources, many varying greatly in brightness, further enriching these constellations and enlivening the high-energy sky!"
