The spiral galaxy GAMA202627 has two dwarf galaxies orbiting it, just like… (Aaron Robotham / ICRAR-St.…)
Our Milky Way is, by and large, a run-of-the-mill galaxy except for one thing. Actually, except for two things: the large and small Magellanic Clouds orbiting it.
Astronomers had previously not seen such dwarf galaxies orbiting another spiral galaxy like ours, leading many to believe that the Milky Way was unique in this respect. But a new study from Australia suggests that although such complicated systems are not common, they are also not unique.
Aaron Robotham of the University of Western Australia and the University of St. Andrews in Scotland and his team used radio telescopes operated by the Australian node of the International Center for Radio Astronomy Research and the Australian Astronomical Observatory to search for similar galaxies in the southern skies.
He reported at the International Astronomical Union General Assembly in Beijing and in an online abstract that about 3% of the galaxies they surveyed had companion galaxies like the Magellanic Clouds.
"In total, we found 14 galaxy systems that are similar to ours, with two of those being an exact match," he said.
"The galaxy we live in is perfectly typical, but the nearby Magellanic Clouds are a rare, and possibly short-lived, occurrence," he added, particularly because they are much larger than most galaxies orbiting others. "We should enjoy them whilst we can, they'll only be around a few billion more years.