Free Astronomy Magazine March-April 2016

the data collected by the Hubble Space Telescope the amount of such dust: 5-10 solar masses. What must thus be looked for is an object enshroued in a huge cloud of dust that from the spectral and photo- metric point of view behaves like Eta Cari- nae and that therefore has the same visible and infrared properties. Inside our Galaxy the search is hampered by various factors, such as the small number of stars of great mass, the need to observe them in a very brief phase of their existence, the excessive overcrowding of many star fields, the presence of obscure interstellar clouds and the difficulty to accurately determine the distances of potential candidates. These problems can be overcome by look- ing for Eta Carinae twin systems in other galaxies, a task undertaken for some years by Rubab Khan, a researcher at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. The first attempts by Khan’s team proved unsuccessful, but they how- ever confirmed the validity of the method of investigation adopted, namely, a target- ed analysis of archival data of the Hubble and Spitzer space telescopes, in the search R ubab Khan, a postdoctoral researcher at NASA’s Goddard Space Flight Center and coordinator of the team that discovered the 5 Eta twins. [NASA]