Astronomers Find a Bunch of ‘Monster Stars’ in Star Cluster

Posted March 18th, 2016 at 4:00 pm (UTC-4)
2 comments

Hubble image shows the central region of the Tarantula Nebula in the Large Magellanic Cloud. Nine stars with more than 100 times the mass of the Sun were found in young and dense star cluster R136, which can be seen at the lower right of the image. (NASA, ESA, P Crowther (University of Sheffield))

Hubble image shows the central region of the Tarantula Nebula in the Large Magellanic Cloud. Nine stars with more than 100 times the mass of the Sun were found in young and dense star cluster R136, which can be seen at the lower right of the image. (NASA, ESA, P Crowther (University of Sheffield))

A group of astronomers probing a young star cluster within the ultraviolet section of the light spectrum just found a bunch of huge ‘monster stars.’

The R136 star cluster, located in the Tarantula Nebula, inside the Large Magellanic Cloud, is about 157,000 light years from Earth.

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.

Relative sizes of young stars, from the smallest “red dwarfs”, weighing in at about 0.1 solar masses, through low mass “yellow dwarfs” such as the Sun, to massive “blue dwarf” stars weighing eight times more than the Sun, as well as the giant star named R136a1 (dark blue) (ESO/M. Kornmesser/Creative Commons)

Relative sizes of young stars, from the smallest “red dwarfs”, weighing in at about 0.1 solar masses, through low mass “yellow dwarfs” such as the Sun, to massive “blue dwarf” stars weighing eight times more than the Sun, as well as the giant star named R136a1 (dark blue) (ESO/M. Kornmesser/Creative Commons)

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.

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

2 responses to “Astronomers Find a Bunch of ‘Monster Stars’ in Star Cluster”

  1. Valeriy says:

    Star formation is one of the least comprehended phenomenon in astrophysics. Is there a general theory of star formation? No, there is not. There is a number of models based on computer simulations which include supersonic hydrodynamics with non-ideal MHD turbulence influenced by gravity. They include the line and continuum radiative processes of the energy transfer; a number of chemical processes with dissociation, recombination and ionization, with uncertain nomenclature of atoms and molecules, unknown magnetic fields and formation and destruction of dust particles. In addition there is macrophysics that is an environment in the molecular clouds, clumps and cores; inclusion in the multiple systems, collisions among stellar systems; jets and outflows; radiation pressure.
    https://www.academia.edu/14720924/The_Star_Formation
    https://www.academia.edu/12369259/On_the_Nature_of_the_Very_Massive_Stars

  2. Just A Nerd says:

    It is incidental to this SW post but the link with the term “electromagnetic radiation spectrum” to the Goddard Space Fight Center’s lessons made my universe of ignorance 1 nanometer smaller.