Gravitational lensing occurs when light from a distant galaxy is subtly distorted by the gravitational pull of an intermediate astronomical object . In this case, the relatively close galaxy cluster MACSJ0138.0-2155 has reflected a significantly more distant dormant galaxy, a sleeping giant known as MRG-M0138.
The distant galaxy MRG-M0138, located about 10 billion light years away from Earth , has already run out of the gas needed to form new stars.
Astronomers can use gravitational lenses like a natural magnifying glass, allowing them to inspect objects like distant dormant galaxies that would normally be too difficult to identify even for the famous Hubble (we're sure not for the James Webb Space Telescope which is scheduled to launch. before the end of the year and that it will rise as the successor to Hubble ).
This image was achieved using observations from eight different infrared filters distributed on two of Hubble's most advanced astronomical instruments: the Advanced Camera for Surveys and the Wide Field Camera 3. These instruments were installed by astronauts during the last two service missions offering a wide range of wavelengths.
Reference: NASA
