NASA’s Gamma-ray Large Area Space Telescope has been successfully calibrated and has begun to map gamma-ray sources throughout the universe. The international mission — which was launched into Earth-orbit in June — has also been renamed the Fermi Gamma-ray Space Telescope in honour of the Italian-American physicist Enrico Fermi.

NASA marked the occasion yesterday by releasing the first data from the satellite: a gamma-ray image of the entire sky taken over four days by Fermi’s Large Area Telecsope (LAT). According to the agency, an image with comparable resolution taken by Fermi’s predecessor (the Compton Gamma-ray Observatory) took several years to obtain.

Working fine

The four-tonne observatory was built by researchers in the US, France, Germany, Italy, Japan and Sweden. It also contains the GLAST Burst Monitor (GBM) to detect transient sources such gamma-ray bursts and solar flares.

Ronaldo Bellazzini of Italy’s University of Pisa — which was involved in building the LAT — told physicsworld.com that the telescope is “working as expected” and has already made several new discoveries regarding pulsars, active galactic nuclei and gamma-ray bursts. “These results will be published shortly”, he said.

However, Bellazzini added that astrophysicists will have to wait a little longer before Fermi begins to deliver meaningful data on one of its prime objectives — shedding light on the nature of dark matter. Certain dark matter particles, called Weakly Interacting Massive Particles, or WIMPs, could annihilate to produce gamma rays, which would show up as tiny gamma-ray signals from the dark-matter haloes that surround galaxies. “It will take about one year to understand the subtleties of the instrument and gather the data,” said Bellazzini.

Proud in Pisa

Bellazzini is particularly pleased with the telescope’s new name because Fermi was a student at the University of Pisa. “Fermi worked at the frontier of particle physics and astrophysics,” he said, citing Fermi’s pioneering work on the acceleration of cosmic rays.

Born in Rome on 29 September, 1901, Fermi won the Nobel Prize for Physics in 1938 for his work on nuclear reactions. That same year he left Italy for the US, where he played an important role in the Manhattan Project. Fermi died in Chicago on 28 November, 1954.