Dark energy camera takes deepest photo yet of galactic siblings

Images from the Survey of the MAgellanic Stellar History (SMASH) reveal a striking family portrait of our galactic neighbors – the Large and Small Magellanic Clouds. The images represent part of the second deepest and most extensive survey of Magellanic Clouds data. The observations consist of approximately 4 billion measurements of 360 million objects.

A sprawling portrait of two astronomical galactic neighbors presents a new perspective on the vortices of stars, gas and dust that make up the neighboring dwarf galaxies known as Large and Small Magellanic Clouds – a pair of dwarf satellite galaxies of our Milky Way. While this isn’t the first survey to map these nearby cosmic siblings, the Magellanic Star History Survey (SMASH) is the most comprehensive survey to date.

The international team of astronomers responsible for the observations used the 520-megapixel high-performance dark energy camera (DECam) on the 4-meter Víctor M. Blanco telescope at the Cerro Tololo Inter-American Observatory (CTIO) in Chile. This data is now available to astronomers around the world through the Astro Data Lab of NOIRLab’s Community Science and Data Center (CSDC). CTIO and CSDC are both programs of NSF’s NOIRLab.

“To date, this is the deepest and most complete astronomical dataset of the Magellanic clouds, which are the large galaxies closest to us,” explains David Nidever, assistant professor in the department. Montana State University Physics and SMASH Investigator Principal Investigator. “These satellite galaxies have been studied for decades, but SMASH is being used to map their structure over their entire extent and help solve the mystery of their formation.”

The full SMASH survey, which includes the view shown in these images, covers an area 2,400 times the size of the full moon and required about 50 nights of specialized observations. This second data release contains new data from DECam on the central and more complex regions of Magellanic clouds. The Large and Small Magellanic Clouds are the largest satellite galaxies in the Milky Way and, unlike the rest of the satellite galaxies, are still actively forming stars – and at a rapid rate.

Although a large number of dwarf galaxies such as the Magellanic clouds populate the Universe, the vast majority are too faint and too far away to be studied by astronomers. Having the Large and Small Magellanic Clouds as neighbors offers astronomers a unique opportunity to study the formation and evolution of small galaxies, but also poses a challenge.

Since the Magellanic clouds are so close to the Milky Way, they spread over much of the sky, making it difficult to map their extent. DECam’s huge field of view has allowed astronomers to capture details in some of the most interesting regions of these dwarf galaxies.

The SMASH team is using its extensive data set to study the history of star formation in these two galaxies. They found evidence that the pair of galaxies collided in the recent past and that this triggered the recent episode of intense star formation.

“These are beautiful multi-colored images of the neighboring galaxies closest to the Milky Way. With the care of the dedicated team, they give us a remarkable view of the thirteen billion year history of star formation in these galaxies, ”notes Glen, program manager for the National Science Foundation. Langston.

One of the team’s long-term goals is to use the information gained from the history of star formation to create a “movie” about how these galaxies have evolved over time. Other topics that the SMASH team hopes astronomers explore include finding star clusters with the help of citizen scientists and measuring the metal content of stars in Magellanic clouds.

“These latest SMASH data from the central regions of Magellanic clouds, where most stars are found, are unique in their combined depth, width and uniformity,” says Knut Olsen, NOIRLab scientist and co-leader of the ‘investigation. “In addition to producing amazing images, this data allows us to look into the past and reconstruct how Magellanic clouds formed their stars over time; with these star-forming ‘films’ we can trying to understand how and why these galaxies evolved. “

This second set of data from the SMASH survey will be made available to the astronomical community jointly through Astro Data Lab, which serves the measurement tables, and the Astro Data Archive, which serves the images, enabling researchers around the world to delve into the history of the Magellanic clouds.

Adam Bolton, Director of the CSDC, explains: “As a modern astronomical research laboratory, NOIRLab provides both the observation platform for teams of scientists to conduct ambitious investigations like SMASH, and the platform data science for the entire astronomical community to exploit the data obtained. products for new discoveries. “

“We’re just getting started,” comments David Nidever. “The data from the SMASH survey has the potential to revolutionize our understanding of the stars that make up Magellanic clouds.”

This research will be presented in the document “The second publication of data from the stellar history survey of the MAgellanic”, in the Astronomical journal.

Provided by NOIRLab