In this artist’s concept of the polarized view of the black hole in M87, lines indicate the direction of polarization, which is related to the magnetic field around the shadow of the black hole. Credit: EHT collaboration
A new image of the M87 shows how it looks in polarized light.
MIT Haystack Observatory is one of 13 stakeholder centers that make up the Horizon Event Telescope (EHT) collaboration, which brought out the ever-present image of its black hole. The EHT today unveiled a new look at the big object at the center of the galaxy M87: how it looks in polarized light. This is the first time astronomers have been able to measure polarization, a signature of magnetic fields, this near the edge of a black hole. The basic ideas for explaining how the galaxy M87, located 55 million light-years away, is capable of launching energetic jets from the heart.
Vincent Fish, Haystack’s research scientist, says “Hundreds of people around the world in EHT collaborations, including scientists and engineers at Haystack, have worked to hard to study the role of magnetic fields in shaping jets around black holes. Can magnetic fields lift and control the intense attraction of gravity? Our data provides an answer. ”
On April 10, 2019, scientists released the first ever image of a black hole, revealing a clear ring-like structure with a dark area in the center – the shadow of the black hole. Since then, the EHT collaboration has examined in more depth the data on the supermassive object at the heart of the galaxy M87 collected in 2017. They have revealed that the famous light ring at the edge of the M87 black hole polished around the ring.
“Astronauts have found a new tool to study black hole magnetism with direct images of light polarization,” explained Kazunori Akiyama, EHT Image Working Group coordinator and research scientist at the Haystack Observatory. “This remarkable task by the Horizon Event Telescope has been truly accomplished by years of international efforts to develop state-of-the-art techniques in all stages of complex signal processing, from the telescopes to the images. . ”
Artist’s impression of M87 and ring in polarization. Credit: Image created by JC Algaba and I. Marti-Vidal.
Light becomes polarized when it passes through special filters, such as polarized sunglasses lenses, or when emitted in hot areas of magnetized space. Similarly, polarized sunglasses only transmit a specific direction of the electric field from the rays of sunlight, astronauts can obtain information about the direction of an electric field coming from outer space, using polarizers installed in their telescopes. In particular, polarization allows astronomers to map the magnetic field present at the inner edge of the black hole.
“Polarization is a powerful tool available to astronauts to study the physical conditions in one of the most remote environments in the universe. It can give an idea not only of the strength and direction of magnetic fields, but also how good those fields are, and perhaps even something about the invisible material between us and the radio transmitter ”said Colin Lonsdale, director of the MIT Haystack Observatory and chairman of the Horizon Event Telescope Board.
The bright jets of energy and material emanating from the M87 core and extending at least 5,000 light-years from its center are one of the most mysterious and vibrant features of the galaxy. Most cases that lie near the edge of a black hole fall into place. However, some of the surrounding grains escape moments before being captured and blown far into space in the form of jets.
Astronomers have relied on different models of how objects are transported near the black hole to better understand this process. But they still don’t know exactly how jets larger than the galaxy will launch from its central region, which is as small in size as the solar system, or just how things are falling apart to the black hole. With the new EHT image of the black hole and its shadow in polarized light, astronauts for the first time looked into the area just outside the black hole, where this interplay is. between subject flowing in and being output happening.
The observations provide new information about the structure of the magnetic fields just outside the black hole. The team found that only theoretical models with strong magnetic gas can explain what they see at the horizon of the event.
“New polarizing images show the powerful jet created by plasma a current trapped by parallel magnetic fields near the black hole, resisting strong gravity attraction, ”explained Kotaro Moriyama, a postdoc overseas member of the Japan Society for the Advancement of Science at the Haystack Observatory.
To observe the heart of the galaxy M87, the collaboration connected eight telescopes around the world, including ALMA (the Atacama Large Millimeter / submillimeter Array) and APEX (the Atacama Pathfinder Experiment) in northern Chile, to create an Earth-sized virtual telescope, the EHT. The impressive resolution obtained by the EHT is equal to the one required to measure the length of a credit card on the lunar surface.
“ALMA has a key role to play in the whole process: it is central to connecting the EHT range, and it is also the most sensitive telescope in the field, so it is vital that you ‘the best of EHT data,’ says Geoff Team, Haystack ‘s research scientist. “Furthermore, the years of work on ALMA polarimetry analysis have provided much more than we thought.”
The event Event Horizon Telescope (EHT), which released the first ever image of a black hole, has today unveiled a new view of the giant object at the center of the Messier 87 galaxy: how it looks in polarized light. This is the first time astronomers have been able to measure polarization, a signature of magnetic fields, this near the edge of a black hole. This video summarizes the findings.
This resolution allowed the team to take a direct look at the shadow of the black hole and the light ring around it, with the new polarized light image clearly showing that the ring is magnetized. The findings are published today in two separate papers in Letters of the Astrophysical Journal with EHT collaboration. The research involved more than 300 researchers from multiple organizations and universities around the world.
The third paper, “Polarimetric Buildings of Event Horizon Telescope Targets from ALMA,” was also published in the Astrophysical Journal Letters, led by Ciriaco Goddi, a scientist at Radboud University and the Leiden Observatory, The Netherlands, and featuring Haystack research scientists Geoff Crew and Lynn Matthews, and based on data from ALMA.
Goddi states, “The ALMA data were obtained at the same time as the VLBI observations made in April 2017 by the EHT (and the GMVA); in this sense, they are a ‘byproduct’ of VLBI activity. ALMA data were crucial for the capitalization, imaging, and elucidation of EHT polarization observations, providing strict limitations on the theoretical models that define how things are conducted near the horizon of the event. black hole. These data also describe the structure of the magnetic field across the powerful relative jets that extend far beyond the galaxy M87. The combined information from the EHT and ALMA allows scientists to study the location of magnetic fields from the event’s horizon neighborhood far beyond the galaxy M87 across its relevant powerful jets (on blades of thousands of light years). ”
The team said, “ALMA is closing the gap in resolution between the ultra-high resolution of the VLBI arrays and those obtained by other measurement methods. Taken together, the richness of new polarimetry data should allow us to make progress in understanding this fascinating thing. “
More on this research:
References:
“First Horizon Telescope Results M87 Event. VII. Polarization of the Ring ”by Telescope Collaboration Event Horizon, Kazunori Akiyama, Juan Carlos Algaba, Antxon Alberdi, Walter Alef, Richard Anantua, Keiichi Asada, Rebecca Azulay, Anne-Kathrin Baczko, David Ball, et al., March 24, 2021 , Astrophysical Journal Letters.
DOI: 10.3847 / 2041-8213 / abe71d
“First Horizon Telescope Results M87 Event. VIII. Magnetic Field Structure near The Event Horizon ”with Event Horizon Telescope Collaboration, Kazunori Akiyama, Juan Carlos Algaba, Antxon Alberdi, Walter Alef, Richard Anantua, Keiichi Asada, Rebecca Azulay, Anne-Kathrin Baczko, David Ball, et al. , 24 March 2021, Astrophysical Journal Letters.
DOI: 10.3847 / 2041-8213 / abe4de
“Polarimetric Buildings Horizon Telescope Targets Events from ALMA” by Ciriaco Goddi, Iván Martí-Vidal, Hugo Messias, Geoffrey C. Bower, Avery E. Broderick, Jason Dexter, Daniel P. Marrone, Monika Moscibrodzka, Hiroshi Nagai, Juan Carlos Algaba, et al., 24 March 2021, Astrophysical Journal Letters.
DOI: 10.3847 / 2041-8213 / abee6a
Find out more
The EHT collaboration includes more than 300 researchers from Africa, Asia, Europe, and North and South America. The international collaboration is working to capture the most accurate black hole images ever obtained by creating a virtual Earth-sized telescope. Backed by international investment, the EHT connects existing telescopes using novel systems – creating a new basic instrument with the highest square resolution power yet achieved.
The individual telescopes involved are ALMA, APEX, IRAM 30-meter Telescope, NOEMA IRAM Observatory, Maxwell James Clerk Telescope, Large Millimeter Telescope, Array Submillimeter, Submillimeter Telescope, South Pole Telescope, Kitt Peitt Telescope , and the Greenland Telescope.
The EHT consortium is made up of 13 stakeholder institutions: Academia Sinica Institute of Astronomy and Astronomy, University of Arizona, University of Chicago, East Asian Observatory, Goethe-Universitaet Frankfurt, Institut de Radioastronomie Millimétrique, Large Telescope Millimeter, Max Planck Institute for Radio Astronomy, MIT Haystack Observatory, Japan National Astronomical Observatory, Perimeter Institute for Theoretical Physics, Radboud University, and Smithsonian Astrophysical Observatory.
This article has been adapted from a publication by Horizon Telescope Event.