the space telescope James Webb continues to reveal incredible photographs of the Universe. The most advanced telescope from NASA, the European Space Agency (ESA) and the Canadian Space Agency, captured the first images of the Orion Nebula, which left astronomers “impressed”, an international research team revealed yesterday.
It’s a wall of dense dust and gas that looks like a huge winged creature, with its maw illuminated by a bright star as it soars through the cosmic filaments. The nebula is located in the constellation of Orion, 1350 light years from Earth, in a similar environment in which our own solar system was born more than 4.5 billion years ago. Astronomers are interested in the region to better understand what happened during the first million years of our planetary evolution.
The images were obtained as part of the program Science of Advance Publication and involved more than 100 scientists in 18 countries, with institutions such as the French National Center for Scientific Research, Western University of Canada and the University of Michigan.
“We are dazzled by the impressive images of the Orion Nebula. These new observations allow us to better understand how massive stars transform the cloud of gas and dust from which they emerged,” Western University astrophysicist Els Peeters said in a statement. Nebulae are often obscured by large amounts of dust that were impossible to see with visible light telescopes, such as the Hubble Space Telescope, the Webb’s predecessor.
However, Webb operates primarily in the infrared spectrum, which penetrates dust. This has allowed the unveiling of several spectacular structures, up to a distance of 40 astronomical units or the size of our solar system. These include dense filaments of matter, which could spawn new generations of stars, as well as star systems consisting of a central protostar surrounded by a disk of dust and gas in which planets form.
“We hope to better understand the full cycle of star birthsaid Edwin Bergin, chair of astronomy at the University of Michigan and member of the international research team. “In this image, we see this cycle where the first generation of stars radiates matter for the next generation. The incredible structures we observe will detail how the star birth feedback loop occurs in our galaxy and beyond.”
The new Webb sighting of Orion shows a multifilter composite image illustrating the emission of ionized gases, hydrocarbons, molecular gases, dust and scattered starlight. The most prominent is Bar Orion, a wall of dense gas and dust that extends from the upper left corner to the lower right corner of this image and contains the bright star θ 2 Orionis A.
The scene is illuminated by a group of hot, young, massive stars (known as the trapezium cluster) just to the upper right of the image. The strong and harsh ultraviolet radiation of the Trapezium cluster creates a hot, ionized environment in the upper right and slowly erodes Orion’s bar. Molecules and dust can survive longer in the protected environment of the dense bar, but the outpouring of stellar energy sculpts a region that displays an incredible richness of filaments, globules, young disc stars and cavities.
The inner region of the Orion Nebula as seen by the James Webb Space Telescope’s NIRCam instrument.
In the first image, a young star is seen inside a globule: as the dense clouds of gas and dust become gravitationally unstable, they collapse into stellar embryos which become progressively more massive until that they can initiate nuclear fusion in their nucleus: they begin to shine. This young star is still embedded in its natal cloud.
The brightest star in this image is θ 2 Orionis A, a sun bright enough to be seen with the naked eye from a dark point on Earth. Starlight reflecting off the dust grains causes the red glow in their immediate surroundings.
At the top left, in the third box you can see in the first box a young star with a disc inside its cocoon. These discs are dissipated or “photo-evaporated” due to the strong radiation field of nearby Trapezium stars, creating a cocoon of dust and gas around them. Nearly 180 externally illuminated photoevaporation disks around young stars (also known as Proplyds) have been discovered in the Orion Nebula, and HST-10 (pictured) is one of the largest known. Neptune’s orbit is shown for comparison.
Below, in the fourth box called Filaments, experts point out that the whole image is rich in filaments of different sizes and shapes. The inset here shows thin, winding filaments that are particularly rich in hydrocarbon molecules and molecular hydrogen.
Orion Nebula: JWST in front of the 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 hot ionized gas emission, highlighting the side of Bar Orion facing the Trapezium cluster (top right of image).
The JWST image also shows cooler molecular material slightly further from the trapezoidal cluster (compare the location of Orion’s bar to the bright star θ2 Orionis A, for example). Additionally, Webb’s sensitive infrared vision can peer through thick layers of dust and see fainter stars. This will allow scientists to study what is happening inside the nebula.
The inner region of the Orion Nebula as seen by both the Spitzer Space Telescope (left) and the James Webb Space Telescope (right). Both images were recorded with a filter particularly sensitive to the emission of hydrocarbon dust which shines over the entire image.
This comparison vividly illustrates how incredibly sharp Webb’s images are compared to its infrared precursor, the Spitzer Space Telescope. This is immediately apparent from the intricate filaments, but Webb’s keen eyes also allow us to better distinguish stars from globules and protoplanetary disks.
Spitzer’s image shows infrared light at 3.6 microns captured by Spitzer’s Infrared Array Camera (IRAC). The JWST image shows 3.35 micron infrared light captured by JWST NIRCam. The black pixels are artefacts due to the saturation of the detectors by the bright stars.
Northern region of M42 seen with NIRCam’s A detector during the Bar Orion survey. Can you find the frog?
Webb is the most powerful space telescope ever built, with a 6.5-meter primary mirror made up of 18 gold-coated hexagonal segments and a five-layer sunshade the size of a tennis court.