Given the place we reside, the Milky Way is essentially the most studied galaxy, which is not shocking.
But learning just one galaxy can solely inform us loads in regards to the complicated strategy of galaxy formation and evolution.
Without trying additional, a key query that can not be solved is whether or not the Milky Way is a starry galaxy, or whether or not it is uncommon or unique.
our analysis, Published today in “Astrophysical Journal Letters”, Showing that the previous is true. The key particulars of the construction of our galaxy are shared by different close by galaxies, which reveals that our house is not that particular.
At first look, we haven’t any purpose to doubt that our galaxy is excellent. Among the billions of galaxies within the observable universe, our galaxy is not the biggest, oldest or most large. It appears to be like similar to all different spiral galaxies, which is the most typical kind of galaxy.
However, when we studied the construction and chemistry of the Milky Way intimately, it started to face out.
From the aspect (it is unimaginable to differentiate the spiral arms), it appears to be like like a pancake with a peach within the center. Astronomers have recognized it for at the very least a century.
However, this straightforward image modified in 1983, when researchers used the Australian telescope Find The historical “thick disk” element of the Milky Way. This faint construction is invisible to the bare eye, which is completely different from the dominant skinny plate (pancake-shaped half), which is clearly seen on a transparent evening, like a starry sky radiating out within the sky.
The skinny disk on which the solar is positioned is about 1,000 light-years thick and 100,000 light-years in diameter, and passes by means of the center of the thick disk on the identical airplane. Appropriately, thick disks are a lot thicker, 1000’s of light-years thick, however the inhabitants density is a lot smaller.
they Recent interesting discoveries It is thick disks and skinny disks that include very completely different sorts of stars. Stars in skinny disks usually include a excessive proportion of heavy parts, such as iron (“metal” in astronomical phrases) and comparatively small quantities of “alpha elements” (carbon, oxygen, magnesium, silicon and a number of other others). At the identical time, the metallic content material of thick disc stars is about 100 instances much less, however the content material of alpha parts is a lot larger.
This double-disk construction has a really unique group of stars, which is troublesome to duplicate in laptop simulations. For a very long time, laptop fashions with the identical construction might solely be created in particular situations involving the collision of a medium-sized galaxy with ourselves about 9 billion years in the past.Simulations present that this course of is extraordinarily uncommon: solely one in all 20 galaxies that seem like just like the Milky Way has skilled a collision. Different thick disks and thin disks.
If this example is right, then galaxies just like the Milky Way must be as uncommon as hens.
Our analysis got down to check this clear prediction. We have studied a number of galaxies which can be roughly just like the Milky Way galaxy utilizing the Multi-unit Spectral Viewer (MUSE) on the very massive telescope. European Southern Observatory In Chile.
Spectroscopy-dividing the sunshine from the Milky Way into many alternative colors-allows us to find out the chemical composition of its stars. What makes MUSE a particularly highly effective instrument is that we can get hold of 90,000 spectra in a single commentary and convert every place within the Milky Way right into a spectrum.
One of the particular galaxies, UGC10738, is about 320 million light-years away from us. It stands out as a result of its side-by-side orientation, which permits us to isolate skinny and thick disk stars and examine them.
We discovered that the chemical composition of stars in UGC 10738 is similar to that within the Milky Way. We discovered that metal-rich, magnesium-poor stars are clustered in a skinny disk alongside the middle of the Milky Way. Above and under the thick disk are a bunch of metal-poor, magnesium-rich stars.
That distant galaxy is similar to our personal galaxy. In flip, because of this there could also be nothing particular in regards to the Milky Way.
Our findings have a number of implications. First, it reveals that the disk-like options within the Milky Way could also be the results of the usual formation path adopted by all galaxies.This bought Recognition of similar structures In a galaxy aside from the Milky Way.
Second, the truth that our galaxy is comparatively regular is very thrilling. This signifies that the Milky Way can be utilized as a blueprint or template for galaxy formation.
This signifies that our house galaxy (clearly the simplest galaxy we research) can maintain the important thing to unlock the cosmic historical past of your complete universe.
Finally, right here is a little bit of hypothesis, the Milky Way is the one galaxy we know of that incorporates life. New analysis means that galactic-scale occasions could have performed a job. Key role in the formation of our solar system. Recent explosions within the discovery of exoplanets point out that programs just like the Milky Way are widespread all through the Milky Way, which means that life can discover many doable houses within the Milky Way.
Now that we know that the historical past of the Milky Way could also be just like billions of different galaxies, evidently they could additionally turn into good houses for all times.
In the tip, it doesn’t matter what future analysis tells us, the Milky Way will nonetheless be our house. This makes it special-although our analysis reveals that it is not particular in one other sense.
Author of this text Nicholas Scott, Postdoctoral researcher in astronomy, University of Sydney, with Jesse van de Sande, ARC DECRA Astronomy Researcher, University of Sydney Repost from conversation Under the Creative Commons license.learn Source article.