Observations of the tiny dwarf galaxy Sparkler have revealed that it is housed in a system of ancient star clusters and is voraciously feeding on smaller galactic companions to grow. that means galaxyDiscovered based on initial data James Webb Space Telescope (JWST), reminiscent of an early cannibal Milky Way, it also grew by feeding smaller galaxies. Therefore, the study of this galaxy gives astronomers a unique insight into how the Milky Way evolved.

FireLocated in the southern constellation of Volens, it got its name because it is surrounded by about two dozen bright stars. globular clusters — close groups of ancient stars. Each of these clusters can contain about a million stars. Currently, our galaxy has about 200 globular clusters of its own.

A team led by Swinburne University Professor Duncan Forbes and San Jose State University Professor Aaron Romanowski examined the age of the Sparkler and its surroundings by looking at the abundance of elements heavier than hydrogen and helium. Astronomers refer to these heavy elements as “metals”.

When they looked at the compact star clusters surrounding the galaxy, they noticed that they looked like younger versions of the clusters around the Milky Way. Many are metal-rich, similar to the globular clusters in the central bulge of our galaxy. Researchers also observed metal-poor, middle-aged clusters associated with Sparkler’s absorbing companion galaxy, and its globular clusters act as deserts.

The Sparkler Galaxy currently only accounts for 3% of the mass of our galaxy, but researchers expect it to grow during this feeding period on cosmic time scales, eventually matching the mass of the Milky Way we see today.

“We’re witnessing firsthand the merging of this galaxy as it formed a dwarf galaxy and several globular clusters,” Forbes said in a statement (opens in a new tab). “We are excited by this unique opportunity to study both the formation of globular clusters and the formation of the Milky Way at a time when the universe is only 1/3 its current age.”

Looking back with a little help from Einstein

Sparkler Galaxy 9 billion miles away light years so astronomers see what Earth is like after about 4 billion years. Big Bang. The observations were made possible thanks to the infrared observing power of the JWST and a phenomenon first predicted by Albert Einstein in 1915.

general theory of relativity The great physicist proposes that objects of great mass “deform” the fabric of space, like a heavy ball placed on a stretched rubber sheet. Just like in this simple analogy, the larger the mass, the more extreme the curve it causes.

This is the case for extremely large objects, such as black holes or galaxies can “pit” space enough to bend light as it passes by. Consequently, if light from a background object passes through this deformation, it will affect the travel time. This can cause the background object to be enhanced by this object descending into the foreground, described as “gravitational lensing”.

The Sparkler galaxy is illuminated by the kind of gravitational lensing that allowed JWST to precisely detect its light, which traveled 9 billion years to reach the powerful space telescope. The team will continue to study globular clusters around Sparkler to learn more about this distant, early galaxy, and then learn more about our own galaxy, the Milky Way, and its evolution.