The Large and Small Magellanic Clouds are the well-known companion galaxies of the Milky Way, but there are many others. At least 61 of them orbit within 1.4 million light-years, while the nearest Andromeda Galaxy is 2.5 million light-years away, but there are likely more.
A team of astronomers is searching for additional companions using the Subaru telescope, but so far only 3% of the sky has been scanned. However, to everyone's surprise, they still found nine previously undiscovered companion galaxies, which is much more than expected, according to The universe today From his report.
The Large Magellanic Cloud in infrared light. Image: ESA/NASA/JPL-Caltech/STScI
Are friends attracted to the Milky Way?
Data from Gaia, a space telescope that collects the precise positions of astronomical objects, indicate that most of the satellite galaxies orbiting our Galaxy are newcomers. Even the two Magellanic Clouds turned out to be newly arrived companions.
They don't know yet whether any of them will be in orbit around the Milky Way. The reason for this is that we do not yet have accurate measurements of the mass of our parent galaxy.
The current research aims to expand knowledge of this corner of the universe through the first detailed research on companion dwarf galaxies. The study, conducted by lead author Daisuke Homma and colleagues at the National Astronomical Observatory of Japan, reports the results of their survey using the Subaru telescope.
Some galaxies accompanying the Milky Way. Wikimedia
The Subaru Telescope is located at the Mauna Kea Observatory in Hawaii, which is located at the Mauna Kea Observatory in Hawaii. It was the largest single-mirror telescope in the world until 2005, with its giant mirror measuring 8.2 metres.
Larger mirrors collect more light into each telescope, which means you can see fainter objects and finer details. Many binoculars have now outgrown Subaru's formidable light-gathering power, but multi-mirror binoculars are becoming increasingly popular.
The cornerstone of the study is an attempt to understand the distribution of dark matter, which suggests that the universe is dominated by dark matter and describes well the large-scale model of the universe. However, he finds it difficult to describe the structure of the local universe that predicts the hundreds of satellite galaxies of the Milky Way.
This detailed artist's rendering shows the structure of the Milky Way, including the location of the spiral arms and other components such as the bulge.
Image: Wikimedia Commons/NASA/JPL-Caltech/ESO/R. Harm
Until recently, we knew of only a few companion galaxies, which contradicted the model and caused a dilemma known as the missing satellite problem.
The Japanese research team hopes their work will help understand the problem, although they admit that their research relied on statistically small numbers and made many assumptions based on the spatial distribution of attendees.
Further progress will require further research into companion galaxy stars and high-resolution imaging.
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