Long before many other galaxies began to spin, the galaxy MACS1149-JD1 holds an early record. Astronomers have detected signs of rotation in this galaxy, which is so far away that its light takes 13.3 billion years to reach Earth.
“The galaxy we analyzed, JD1, is the most distant example of a rotational galaxy ,” says astronomer Akio Inoue of Waseda University in Tokyo and co-author of the paper published in The Astrophysical Journal Letters.
Because as telescopes have become more advanced and powerful, astronomers can detect more and more distant galaxies. These are some of the earliest galaxies to form in our universe that began to move away from us as the universe expanded.
The galaxy was discovered in 2012
Recently, the ALMA telescope has observed redshifted emissions from a distant galaxy, MACS1149-JD1, which has led to some interesting conclusions. “Beyond finding high redshift galaxies, that is, very distant, studying their internal movement of gas and stars provides a motivation to understand the process of galaxy formation in the earliest possible universe”, clarifies Richard S. Ellis , co-author of the study.
The team, led by Tsuyoshi Tokuoka at Waseda University in Tokyo, used the Atacama Large Millimeter/submillimeter Array (ALMA) to make observations over a two-month period of this galaxy that existed in the early universe, just 500 million years after the Bigbang . By fitting a model to their observations, the team found that a small, slowly rotating galaxy provides the best fit to the data.
This galaxy appears to be 3,000 light-years across, compared to the Milky Way’s 100,000 light-years; and its rotation speed is only 50 kilometers per second (the Milky Way moves at 220 kilometers per second). About a quarter of the spin rate of the Milky Way.
“JD1’s rotation rate is much slower than that found in galaxies at later epochs and our [Milky Way] galaxy, and JD1 is likely to be in an early stage of developing a rotational motion,” he says. Akio K. Inoue, co-author of the study.
james webb
Experts plan to use the James Webb Space Telescope in 2023 to examine this galaxy in more detail and refine the setting for its formation. How did this galaxy and other galaxies like ours form?
“The origin of the rotational movement in galaxies is closely related to a question: how did galaxies like the Milky Way form?” explains Inoue. “So it’s interesting to find the start of rotation in the early universe .”
Referencia: Tsuyoshi Tokuoka, Akio K. Inoue, Takuya Hashimoto, Richard S. Ellis, Nicolas Laporte, Yuma Sugahara, Hiroshi Matsuo, Yoichi Tamura, Yoshinobu Fudamoto, Kana Moriwaki, Guido Roberts-Borsani, Ikkoh Shimizu, Satoshi Yamanaka, Naoki Yoshida, Erik Zackrisson, Wei Zheng. Possible Systematic Rotation in the Mature Stellar Population of az = 9.1 Galaxy. The Astrophysical Journal Letters, 2022; 933 (1): L19 DOI: 10.3847 / 2041-8213 / ac7447
