They chose to explore in the ultraviolet range since there are so many hot and extremely massive stars in the cluster that mostly radiate energy within that part of the electromagnetic radiation spectrum.
The group used a combination images gathered by the Hubble Space Telescope’s Wide Field Camera 3 (WFC3) and the Space Telescope Imaging Spectrograph (STIS) to detect dozens of stars with at least 50 times the mass of the sun and about nine others with more than 100 times the solar mass.
The nine most massive of these stars were found to be not only incredibly enormous, but together they produce an extremely bright light that is 30 million times more luminous than our own Sun.
While the group was able to spot a number of supermassive stars, a previously detected star in the cluster called R136a1 is the most massive star known to exist in the Universe. It has a solar mass of about 265 times that of the Sun and is thought that to have had a solar mass of about 320.
The astronomer’s findings were outlined in a paper published by the Monthly Notices of the Royal Astronomical Society,
“The ability to distinguish ultraviolet light from such an exceptionally crowded region into its component parts, resolving the signatures of individual stars, was only made possible with the instruments aboard Hubble,” explains the paper’s lead author Paul Crowther of the United Kingdom’s University of Sheffield in a press release.
Another of the paper’s authors, Saida Caballero-Nieves, also from the University of Sheffield, said that while some scientists have previously suggested that these monster stars were created by the merger of smaller binary system stars, this doesn’t really explain the supermassive stars in the R136 cluster.
Instead, he says that it appears the road that led to the huge size of these stars may have begun with its formation process.
The astronomers plan to continue analyzing the Hubble data they’ve gathered to learn more about the giant star’s origination.
They’ll also analyze new information from the Space Telescope’s Imaging Spectrograph to look for nearby binary star systems, where orbiting black hole binaries may lurk.
The twin black holes would eventually merge and produce the gravitational waves such as those predicted by Einstein in his Theory of General Relativity and were only recently detected by the LIGO Scientific Collaboration.