Free Astronomy Magazine May-June 2016

SPACE CHRONICLES I n this huge image of part of the southern constellation of Norma (The Car- penter’s Square) wisps of crimson gas are illuminated by rare, massive stars that have only recently ignited and are still buried deep in thick dust clouds. The vast nebula where these giants were born, known as RCW 106, is cap- tured here in fine detail by ESO’s VLT Survey Telescope (VST), at the Paranal Observatory in Chile. Many other interesting objects are also captured in this wide-field image. For example the filaments to the right of the image are the remnants of an ancient supernova (SNR G332.4-00.4, also known as RCW 103), and the glowing red filaments at the lower left surround an unusual and very hot star (RCW 104, surrounding the Wolf–Rayet star WR 75). Patches of dark obscuring dust are also visible across the entire cosmic landscape. [ESO] and the shortness of their lifetimes, means that they are very rare — only one in every three million stars in our cosmic neighbourhood is an O-type star. None of those that do exist are close enough for detailed investiga- tion and so the formation of these fleeting stellar giants remains mys- terious, although their outsized in- fluence is unmistakeable in glowing HII regions like this one. n