Life around other stars
An image of galaxy NGC 3310 has been animated to give the impression of the rotation of galaxies.
This colour image shows the elliptical galaxy NGC 4365. The image is a combination of two exposures taken with the NASA/ESA Hubble Space Telescope (Wide Field Planetary Camera 2) on 31 May 1996 and one taken with ESO’s Very Large Telescope (multi-mode ISAAC instrument on the 8.2-m VLT ANTU telescope at the ESO Paranal Observatory, Chile).
By combining these images a group of European and American astronomers have made a major discovery. They have identified a huge number of 'young' stellar clusters, in an old elliptical galaxy. For the first time, it has been possible to identify several distinct periods of star formation in a galaxy as old as this one. Elliptical galaxies have always been considered to have undergone one initial star-forming period and thereafter to be devoid of star formation.
NGC 4365 is located in the constellation of Pegasus at an approximate distance of 55 million light-years. The images were taken through a green filter (V-band, 2200 seconds, coloured blue), a red filter (I-Band, 2300 seconds, coloured green) and an infrared filter (K-band, 9500 seconds, 0.6 arcseconds seeing, coloured red).
Credits: ESA/ESO-Markus Kissler-Patig (ESO) & Thomas H. Puzia (University of Munich)