Astronomers using the NASA/ESA/CSA James Webb Space Telescope have captured the most detailed images ever of the Horsehead Nebula, one of the most distinctive objects in our sky.
At the bottom of this Web/NIRCam image, a small portion of the Horsehead Nebula is visible up close as a curved wall of thick, smoky gas and dust. Above the nebula, various distant stars and galaxies can be seen all the way to the top of the image. Image credits: NASA / CSA / ESA / Webb / K. Misselt, University of Arizona / A. Abergel, IAS, Université Paris-Saclay, CNRS.
The Horsehead Nebula is located in the constellation Orion, about 1,500 light-years from Earth.
Also known as Barnard 33, this nebula is visible only because its indistinct dust is silhouetted against the brighter nebula IC 434.
The Horsehead Nebula is just one small feature of the Orion Molecular Cloud Complex, with the glowing Flame Nebula dominating the center of this view.
The nebula was first recorded by Scottish astronomer Williamna Fleming on February 6, 1888.
The object is formed by a collapsing cloud of interstellar matter and shines in the light of a nearby hot star.
The gas cloud surrounding the horsehead has now disappeared, but the protruding columns are made of stronger material that is less erodible.
Astronomers estimate that the Horsehead Formation has about 5 million years left to collapse.
The new image from the web focuses on the upper illuminated edge of the nebula’s characteristic dust and gas structures.
This Webb/MIRI image is more than half filled from bottom to top with a small section of the Horsehead Nebula. Image credits: NASA / CSA / ESA / Webb / K. Misselt, University of Arizona / A. Abergel, IAS, Université Paris-Saclay, CNRS.
“The Horsehead Nebula is well known. photodissociation region (PDR),” astronomer Webb said.
“In such regions, ultraviolet light from young massive stars creates a region of warm, nearly neutral gas and dust between the fully ionized gas around the massive star and the clouds they are born into. .”
“This UV radiation has a strong effect on the gas chemistry in these regions and acts as the most important heat source.”
“These regions occur where the interstellar gas is concentrated enough to remain neutral, but not dense enough to prevent the transmission of deep ultraviolet light from massive stars.”
“Light emitted from such PDRs will be used to study the physical and chemical processes that drive the evolution of the interstellar medium in our galaxy and throughout the universe from the early days of active star formation to the present day. We provide unique tools for
“The Horsehead Nebula, due to its close proximity and near-edge-on geometry, provides an opportunity for astronomers to study the physical structure of the PDR and the evolution of the chemical properties of gas and dust within their respective environments and transition regions. is an ideal target for “among them. “
“This is considered one of the best objects to study how radiation interacts with the interstellar medium.”
“Thanks to Mr. Webb. mm (mid-infrared measuring instrument) and NIRCam “We used (near-infrared camera) equipment to reveal for the first time small-scale structures at the end of an illuminated horsehead,” they said.
“We also detected a network of stripes extending perpendicular to the PDR front and containing dust particles and ionized gas entrained in the nebula's photoevaporative flow.”
“These observations allowed us to investigate the effects of dust attenuation and ejection, and to better understand the multidimensional shape of the nebula.”
“Next, we will study the spectroscopic data obtained from the nebula to demonstrate the evolution of the physical and chemical properties of the material observed throughout the nebula.”
of result appear in the diary astronomy and astrophysics.
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A. Abergel other. 2024. His JWST observations of the horsehead photon-dominated region I. First results from multiband near-infrared and mid-infrared imaging. A&A, in press. doi: 10.1051/0004-6361/202449198
Source: www.sci.news
