New Webb images reveal spectacular view of the Orion Nebula
The James Webb (Webb) Space Telescope has again demonstrated its incredible power by capturing the most detailed and sharp images ever taken of the inner region of the Orion Nebula. This stellar nursery is located in the constellation Orion and is about 1,350 light-years away from Earth. Researchers at Western University in Ontario, Canada, participated in an international collaboration targeting the newly released images. “We are amazed by the fascinating images of the Orion Nebula. We started this project in 2017, so we waited more than five years to get this data,” said Western astrophysicist Els Peeters. These images were taken as part of the Early Release Science Photodissociation Regions for All (PDRs4All ID 1288) program at JWST. Led by Peeters, French National Center for Scientific Research (CNRS) scientist Olivier Berné, and Institute for Astrophysical Spatial (IAS) associate professor Emilie Habart, PDRs4All is an international collaboration involving a team of more than a hundred scientists in 18 countries. Other Western University astrophysicists involved in PDRs4All include Jan Cami, Ameek Sidhu, Ryan Chown, Bethany Schefter, Sofia Pasquini, and Baria Kahn. Young star with a disk inside its cocoon: A planet that forms disks of gas and dust around a young star. These discs are diffused or ‘photographed’ by the strong radiation field of nearby Trapezium stars creating a cocoon of dust and gas around them. Nearly 180 of these outwardly luminous photoevaporation disks around young stars (aka Proplyds) have been discovered in the Orion Nebula, and HST-10 (the one pictured) is one of the largest known. Neptune’s orbit is shown for comparison. Threads: The entire image is rich in threads of different sizes and shapes. The inset here shows thin, spiral filaments that are particularly rich in hydrocarbon molecules and molecular hydrogen. θ2 Orionis A: The brightest star in this image is θ2 Orionis A, a star that is bright enough to be seen with the naked eye from dark location on Earth. Starlight reflected off dust grains causes the red glow in its immediate surroundings. Young star within the globule: When dense clouds of gas and dust become gravitationally unstable, they collapse into stellar embryos that gradually grow until they begin nuclear fusion at their core – they begin to glow. This young star is still embedded in its natal cloud. Credit: NASA, ESA, CSA, Data reduction and analysis: PDRs4All ERS Team; graphic editing S. Fuenmayor & O. Berné “These new observations allow us to better understand how massive stars transform the cloud of gas and dust in which they are born,” said Peeters. She is a professor of Western astronomy and a faculty member at the Institute for Earth and Space Exploration. “Big young stars emit large amounts of UV radiation directly into the intrinsic cloud that still surrounds them, and this changes the physical shape of the cloud as well as its chemical composition. Exactly how this works and how it affects further star and planet formation is not yet well understood.” Newly released images reveal numerous spectacular structures within the nebula, on scales comparable to the size of the Solar System. “We clearly see quite dense filaments. These filamentary structures may give rise to a new generation of stars in the deeper regions of the dust and gas cloud. Star systems that have already formed also appear,” Berné said. “Within its cocoon, young stars with a disk of dust and gas in which planets form are observed in the nebula. Small craters dug by young stars blown by the intense radiation and stellar winds of newborn stars are also clearly visible.” Proplyds, or ionized protoplanetary disks, consist of a central protostar surrounded by a disk of dust and gas in which planets form. Scattered throughout the images are several protostellar jets, outflows, and emerging stars embedded in the dust. “We have never been able to see the intricate fine details of how interstellar matter is structured in these environments and understand how planetary systems can form in the presence of this harsh radiation. These images reveal the legacy of the interstellar medium in planetary systems,” said Habart. Orion Nebula: JWST vs. Hubble Space Telescope (HST): The inner region of the Orion Nebula as seen by both the Hubble Space Telescope (left) and the James Webb Space Telescope (right). The HST image is dominated by emission from hot ionized gas, highlighting the side of the Orion line facing the Trapezium cluster (upper right of the image). The JWST image also shows the cooler molecular material located a bit farther from the Table Cluster (compare the position of Orion’s bar relative to the bright star θ2 Orionis A for example). Webb’s sensitive infrared vision can additionally see through thick layers of dust and see fainter stars. This will allow scientists to study what is happening deep within the nebula. Credits: NASA, ESA, CSA, PDRs4All ERS Team; image processing by Olivier Berné. HST image credit: NASA/STScI/Rice Univ./C.O’Dell et al. – Program ID: PRC95-45a. Technical details: The HST image used a WFPC2 mosaic. This composite image uses [OIII] (blue), ionized hydrogen (green) and [NII] (Red).
Analogous development
The Orion Nebula has long been considered an environment similar to the cradle of the Solar System (when it formed more than 4.5 billion years ago). This is why scientists today are interested in observing the Orion Nebula. They hope to understand, by analogy, what happened during the first million years of our planetary evolution. Because the hearts of stellar nurseries like the Orion Nebula are shrouded in large amounts of stardust, it makes it impossible to study what’s going on inside them in visible light with telescopes like the Hubble Space Telescope. Webb detects the infrared light of the universe, which allows astronomers to see through these layers of dust and reveal the action going on deep within the Nebula. The inner region of the Orion Nebula as seen by the Spitzer Space Telescope (left) and the James Webb Space Telescope (right). Both images were captured with a filter that is particularly sensitive to the emission of hydrocarbon dust that shines across the image. This comparison impressively shows how incredibly sharp Webb’s images are compared to its infrared forerunner, the Spitzer Space Telescope. This is immediately clear from the intricate filaments, but Webb’s sharp eyes also allow us to better distinguish stars from globules and protoplanetary disks. image processing by Olivier Berné. Credit for the Spitzer image: NASA/JPL-Caltech/T. Megeath (University of Toledo, Ohio) Technical details: The Spitzer image shows infrared light at 3.6 microns captured by Spitzer’s Infrared Array Camera (IRAC). The JWST image shows infrared light at 3.35 microns recorded by the JWST NIRCam. Black pixels are artifacts due to detector saturation by bright stars. “Observing the Orion Nebula was a challenge because it is too bright for Webb’s unprecedentedly sensitive instruments. But Webb is incredible, Webb can observe distant and faint galaxies, as well as Jupiter and Orion, which are some of the brightest sources in the infrared sky,” Berné said. At the heart of the Orion Nebula is the “trapezium cluster” (also known as Theta Orionis), discovered by Galileo. It contains young, massive stars whose intense ultraviolet radiation shapes the cloud of dust and gas. Understanding how this intense radiation affects their environment is a key question for understanding the formation of star systems like our own solar system. “Seeing these first images of the Orion Nebula is just the beginning. The PDRs4All team is working hard to analyze the Orion data, and we look forward to new discoveries about these early phases of star system formation,” said Habart. “We are thrilled to be a part of Webb’s journey of discovery.” Webb is the most powerful space telescope ever built in human history. Developed in collaboration with NASA, the European Space Agency and the Canadian Space Agency (CSA), it features an iconic 6.5 meter wide mirror, consisting of a honeycomb-like pattern of 18 gold-plated hexagonal mirror segments and a five-layer , diamond-shaped, tennis-court-sized sunscreen. As a partner, CSA receives a guaranteed share of Webb’s observing time, making Canadian scientists among the first to study data collected by the most advanced space telescope ever built.
