We might be more special than thought, astronomers have revealed.
A new study has discovered the the Milky Way, which is home to Earth and its solar system, could in fact be an outlier, and not a ‘normal’ galaxy as they had previously thought.
Early results from the Satellites Around Galactic Analogs (SAGA) Survey indicate that the Milky Way’s satellites are much more tranquil than other systems of comparable luminosity and environment.
You are here: The Milky Way is a barred spiral galaxy that measures around 100-light-years across and is home to our solar system. Early results from the Satellites Around Galactic Analogs (SAGA) Survey indicate that the Milky Way’s satellites are much more tranquil than other comparable systems.
The Milky Way, which is home to Earth and its solar system, is host to several dozen smaller galaxy satellites which orbit around the Milky Way and are useful in understanding the Milky Way itself.
Early results from the Satellites Around Galactic Analogs (SAGA) Survey indicate that the Milky Way’s satellites are much more tranquil than other systems of comparable luminosity and environment.
Many satellites of those ‘sibling’ galaxies are actively pumping out new stars, but the Milky Way’s satellites are mostly inert, the researchers found.
This is significant, according to the researchers, because many models for what we know about the universe rely on galaxies behaving in a fashion similar to the Milky Way.
‘We use the Milky Way and its surroundings to study absolutely everything,’ said Yale astrophysicist Marla Geha, lead author of the paper, which appears in the Astrophysical Journal.
‘Hundreds of studies come out every year about dark matter, cosmology, star formation, and galaxy formation, using the Milky Way as a guide.
Early results from the Satellites Around Galactic Analogs (SAGA) Survey indicate that the Milky Way’s satellites are much more tranquil than other systems of comparable luminosity and environment.
‘But it’s possible that the Milky Way is an outlier.’
The SAGA Survey began five years ago with a goal of studying the satellite galaxies around 100 Milky Way siblings.
Thus far it has studied eight other Milky Way sibling systems, which the researchers say is too small of a sample to come to any definitive conclusions.
SAGA expects to have studied 25 Milky Way siblings in the next two years.
Yet the survey already has people talking.
This is a three-color optical image of a Milky Way sibling, which the team used in the study.
At a recent conference where Geha presented some of SAGA’s initial findings, another researcher told her, ‘You’ve just thrown a monkey wrench into what we know about how small galaxies form.’
‘Our work puts the Milky Way into a broader context,’ said SAGA researcher Risa Wechsler, an astrophysicist at the Kavli Institute at Stanford University.
‘The SAGA Survey will provide a critical new understanding of galaxy formation and of the nature of dark matter.’
Wechsler, Geha, and their team said they will continue to improve the efficiency of finding satellites around Milky Way siblings.
‘I really want to know the answer to whether the Milky Way is unique, or totally normal,’ Geha said.
‘By studying our siblings, we learn more about ourselves.’