A team of scientists led by Sweden’s Chalmers University of Technology studied two galaxies in the early universe that contained highly productive star factories. Scientists used powerful telescopes to split the galaxy’s light into individual colors and were surprised to discover light from more different molecules than ever before at such distances. Researchers believe such studies could revolutionize our understanding of the lives of the most active galaxies when the universe was young.
When the universe was young, galaxies were much different from today’s stately spirals, filled with gently shining suns and colorful gas clouds. New stars were being formed hundreds of times faster than the universe today. But most of it is hidden behind a thick layer of dust, making it difficult for scientists to uncover the secrets of these star factories until now. By studying the most distant galaxies visible with powerful telescopes, astronomers can get a glimpse of how these factories were able to produce so many stars.
new study,It was published in the magazine astronomy and astrophysicsA team of scientists led by Chalmers astronomer Chentao Yang NOEMA (North Extended Millimeter Wave Array) I went to France to find out more about how these early star factories were able to produce so many stars. Yang and his colleagues measured the light from his two bright galaxies in the early universe. One of his was classified as a quasar, and both had high star formation rates.
“We knew that these galaxies were tremendous star factories, perhaps some of the largest the universe had ever seen. How they work To find out, we measured their light at a wavelength of about 1 millimeter, in hopes of gleaning new clues,” says Chentao Yang.
Dramatic chemical reactions in distant galaxies thrill astronomers
The measurements proved more successful than scientists expected. They identified signatures of different types of molecules in the light recorded from both galaxies. From deep within these galaxies, light of different wavelengths emanates from the clouds of gas and dust where new stars are born.
“It’s an amazing explosion of color, with shades invisible to the human eye. But by combining our observations with our knowledge of physics and chemistry, we can understand the meaning of the colors and discover the differences between different galaxies. “We can see if there is a difference,” said astronomer and research team member from the ESO and ALMA joint observatories in Chile.
By analyzing each galaxy’s spectrum (the individual colors of its light), scientists were able to identify 13 molecules, some of which had never been observed before in a galaxy this far away. There was no. Each molecule gives different clues about the temperature, pressure, and density of the interstellar space and how starlight, radiation, and matter interact, and about the physical and chemical conditions of these galaxies. Provide important new information.
“The signals are difficult to interpret. We see parts of the electromagnetic spectrum that are difficult to observe in nearby galaxies. But thanks to the expansion of the universe, we are seeing a part of the electromagnetic spectrum that is difficult to observe in nearby galaxies. “The light is shifting to longer wavelengths that can be seen with submillimeter radio telescopes,” says Chentao Yang.
It’s more like a neon-lit city than a night under the stars.
The two galaxies the team studied are so far apart that it takes almost 13 billion years for their light to reach us.
“Seeing these galaxies is more like seeing a neon-lit city than a night under the stars,” says Chalmers astronomer and team member Suzanne Aalto.
Astronomers are used to photographing star factories in our galaxy, such as the Orion and Carina nebulas, she explains.
“In these two distant galaxies, we instead see star factories that are larger, brighter, dust-filled, and different in many ways. In these two distant galaxies, ultraviolet light cannot penetrate through the dust layers. Instead, much of the illumination comes from cosmic rays, from exploding stars and near supermassive black holes. Thanks to the high-energy particles that are produced,” says Suzanne Aalto.
Galaxies in the early universe can now tell their stories
Although galaxies like these two are rare, scientists plan to use both NOEMA and its even larger sister telescope to study many more. ALMA Telescope (Atacama Large Millimeter/Submillimeter Array) In Chile. Both telescopes are sensitive to light at wavelengths of about 1 millimeter.
“Our results demonstrate how NOEMA, with its broadband receivers and powerful correlator computer, opens up new opportunities to study such extreme galaxies in the northern sky from the southern hemisphere. ALMA’s planned broadband sensitivity upgrade will provide even more exciting prospects. The most remarkable galaxies of the early universe will finally be able to tell their stories through their molecules. ,” says astronomer Pierre Cox of CNRS and Sorbonne University in France.
Research results details:
- More than 100 different molecules have been detected in interstellar space. In this study, astronomers investigated the molecules of carbon monoxide (CO), cyano radical (CN), ethynyl radical (CCH), hydrogen cyanide (HCN), formyl cation (HCO+), hydrogen isocyanide (HNC), and carbon monosulfide. Identified. (CS), water (H2O), hydronium ion (H)3O+), nitric oxide (NO), diazenylium (N2H+), methylidine radical (CH), and cyclopropenylidene (cC3H2). Some of these (CH, CCH, cC3H2,N2H+ and H3O+) has never been observed at such a long distance.
- The two galaxies studied have catalog numbers APM 08279+5255 and NCv1.143. Previous studies have shown that they are so far away that their light has been traveling toward us for almost 13 billion years, corresponding to a redshift of 3.911 and 3.565, respectively. . Redshift means that the expansion of the universe stretches light from distant galaxies to longer wavelengths, which can be observed with radio telescopes.
- Despite their distance, galaxies shine brightly at radio wavelengths. Those signals are amplified thanks to other galaxy clusters along the path of the light. This is an effect known as gravitational lensing. One of his galaxies, APM 08279 + 5255, is also a quasar, a galaxy whose center shines brightly from radio waves to her X-rays due to matter swirling around a supermassive black hole. NCv1.143 may also contain a central black hole.
Research group and paper details:
- The research was published in a paper, Sunrise: Broadband spectral line survey reveals rich molecular inventory of high-redshift dusty galaxies,It was published in the magazine astronomy and astrophysics.
- The team consisted of Chentao Yang (Chalmers University of Technology, Sweden), Alain Aumont (CNRS and Sorbonne University, France), Sergio Martin (ESO and the joint ALMA Observatory, Chile), and Thomas G. Bisbas (Zhejiang Research Institute, China). ). , Pierre Cox (CNRS and Sorbonne University, France), Alexandre Behlen (Aix-Marseille University, France), Eduardo González-Alfonso (Alcalá University, Spain), Rafael Gavazzi (Aix-Marseille University), Suzanne Aalto (Chalmers University of Technology), Paola Andreani (ESO), Cecilia Ceccarelli (University Grenoble Alpes, CNRS), Yu Gao (Xiamen University, China), Mark Gorski (Chalmers University of Technology), Michel Guélin (IRAM, France), Hai Fu ( University of Iowa, USA), Rob J. Ivison (ESO, Macquarie University, Dublin IAS, University of Edinburgh), Kirsten K. Knudsen (Chalmers University of Technology), Matthew Lehnert (Lyon Astrophysics Center, CRAL, France), Hugo Messias ( ESO and the joint ALMA Observatory), Sebastian Muller (Chalmers University of Technology), Roberto Neri (IRAM), Dominik Riechers (University of Cologne), Paul van der Werf (Leiden University, Netherlands), Zhi-Yu Zhang (Nanjing University, China)) .
Learn more about Noema:
NOEMA, Northern Extended Millimeter Wave Arrayis the most powerful millimeter-wave observatory in the Northern Hemisphere, located at 2500 meters above sea level on the Buhl Plateau in the French Alps and operated by IRAM. It consists of an array of twelve 15 meter individual antennas. During observations, the antenna acts as a single telescope using a technique called interferometry.
For more information, please contact us below.
- Robert Cumming, astronomer and correspondent, Onsala Space Observatory, Chalmers University of Technology, Sweden, robert.cumming@chalmers.se, +46 70 493 31 14
- Chentao Yang, Astronomer, Chalmers University of Technology, Sweden, Department of Space, Earth and Environment, chentao.yang@chalmers.se
Both representatives speak English, and Chentao Yang also speaks Chinese. Available for live and pre-recorded interviews. Chalmers has an on-site podcast studio and broadcast filming equipment and can accommodate television, radio and podcast interview requests.
