Hidden galaxy
New observations of the Small Magellanic Cloud show that it might actually be two galaxies disguised as one
The Small Magellanic Cloud (SMC) is a nearby galaxy that’s very familiar to astronomers, or so they thought. New research suggests that the satellite galaxy of the Milky Way, located around 199,000 light years from Earth, seems to have been hiding a secret – it’s actually two galaxies, one behind the other. To make the discovery, a team led by Claire Murray, an astronomer at the Space Telescope Science Institute in Maryland, tracked the movement of gas clouds and young stars being born within them around the SMC. They found that the small galaxy, which is around 18,900 light years wide – less than one-fifth the width of the Milky Way – contains two distinct stellar nurseries thousands of light years apart. Both the SMC and the Large Magellanic Cloud (LMC) are dwarf galaxies that are gravitationally bound to the Milky Way and are being steadily drawn towards our galaxy for a collision and merger in the far future.
While the LMC exhibits a disc-like shape similar to that of the Milky Way, the SMC is more irregular. The SMC has only one-third the mass of the larger dwarf galaxy, which has a mass equivalent to around 7 billion times that of the Sun. Although the SMC was previously thought to consist of multiple components, it’s somewhat obscured by interstellar clouds of gas and dust, meaning these features have been hard to distinguish.
Murray has prev
