The “Interpretation of the First Observation Results of the James Webb Space Telescope” series is a series of articles explaining the interpretation of observations and future prospects of James Webb from the perspective of a Science Times reporter and astronomer.
In the James Webb Space Telescope Observation Interpretation series, we dig through high-resolution images one by one to find out what the pictures mean and what James Webb’s plans for the future of celestial bodies are. James Webb’s fourth image was a highly detailed “cosmic cliff” of the Keel Nebula, which made it a hot topic as it allowed us to understand the detailed structure of a previously unseen star forming region.
Interstellar matter and what is a nebula?
Interstellar matter refers to matter that exists in the empty space between stars. The space above is not a vacuum, and various substances exist in various phases, usually very sparse compared to the average density of stars. Most of the interstellar matter consists of interstellar dust/grain and interstellar gas, and it is classified into several different forms, such as molecular clouds, depending on the density and temperature. Therefore, observation of interstellar matter is possible at all wavelengths.
Interstellar matter is dispersed throughout the galaxy, and a relatively high density of such matter in a particular space for some reason is called a nebula. In other words, a nebula is a collection of dust and gas that exists between stars. Nebulae are usually very large, with some nebulae exceeding 1,000 light-years in diameter.
type of nebula
Because nebulae are composed of interstellar dust and gas, they cannot emit light by themselves. However, for various reasons, it can be observed from Earth, and it is usually divided into three types depending on how dust and gas interact.
First, the Emission Nebula is a nebula in which gas and dust are heated from surrounding stars and ionized hydrogen atoms recombine to give light. This corresponds to Excited stars supplying ionization energy are usually hot stars with a surface temperature of over 30,000 K. Most nebulae are like this.
Orion Nebula © NASA, ESA, M. Robberto
A Dark Nebula is a nebula that does not shine on its own, but appears dark when the gas and dust of the nebula obscures the light of bright stars or nebulae from the background of the nebula when observed from Earth. Horsehead Nebula, et al. In fact, it is a shadow of interstellar matter, and observations of dark nebulae indicate that the density of gas and dust in this area is higher than that in its surroundings.
The Horsehead Nebula © Ken Crawford
Finally, the Reflection Nebulae is the rarest type of nebula that reveals itself by reflecting light from nearby stars. This is the Witch Head Nebula in Orion.
The Old Lady Nebula © NASA/STScI Digitized Sky Survey/Noel Carboni
Carina Nebula
The Carina Nebula (or Eta Carinae Nebula η Carinae Nebula, NGC name: NGC 3372) is a large, complex nebula located about 7,600 light-years (1 light-year is 9.460 billion km) from Earth. The upper nebula is brighter and larger than the Orion Nebula. However, as a nebula that can be observed from the southern hemisphere, it has become a relatively less famous celestial body due to the concentration of celestial objects observed in the northern hemisphere. It is home to bright and dark nebulae and many unusual celestial bodies, as well as a number of remarkable astronomical phenomena. The Carina Nebula is also the brightest spot in the Milky Way.
Eta Carinae (η Carinae), the brightest star in the Carina Nebula, is a young star about 3 million years old, but a very bright hypergiant. The above star was the brightest star observable from Earth just over 200 years ago, but it has recently become a hot topic due to its dramatic darkening. This is predicted to be due to the imminent supernova explosion due to the very heavy mass at the time the star was born. Many stars in the nebula, as well as Eta above, are likely to evolve into supernovae. The James Webb Space Telescope was launched to observe the Carina Nebula, which is of great astronomical significance.
From left, the Carina Nebula, NGC 3324 Open Cluster, and the edge of the NGC 3324 Open Cluster “Cosmic Cliff” © Hubble/NASA, ESA, JWST/NASA, ESA, CSA, STScI
in the northwestern corner of the Carina Nebula
NGC 3324 Open Cluster Edge “Cosmic Cliff” NIRCam Image
NGC 3324 open cluster edge “cosmic cliff” at the northwestern corner of the Carina Nebula. NIRCam Image© NASA, ESA, CSA, STScI
Above is an image of the Carina Nebula taken with the James Webb Space Telescope’s Near Infrared Camera (NIRCam). The north and east compass arrows show the direction of the image when viewed from below, and the direction when viewed from above should be reversed. The scale bar is expressed in light years, the distance light travels in one year, and it takes about two years for light to travel the length of the scale bar. For reference, one light-year is equal to 9,460 billion km (or about 5.88 trillion miles). From this, it can be seen that the size of the celestial body shown in the above image is about 12 light-years.
The image above shows the invisible near-infrared wavelength converted into visible light color. The letters listed in different colors below the photo indicate the NIRCam filter that was used to collect the light. The color of each filter name is the color of visible light used to indicate the near and mid infrared passing through that filter, and is a composite of individual exposures.
The area on the left edge of the picture looks like a “craggy mountain on a moonlit evening,” according to NASA. This is the NGC 3324 open cluster where young stars are formed. It represents a group of thousands of stars of similar age born in the same molecular cloud. ) is the edge of
Captured in infrared, this image shows the star forming region. For reference, NGC 3324 was first observed and recorded by Dr. James Dunlop in 1826. The above area was already photographed by Hubble in 2008, and astronomers were amazed at the dynamic image of a real cliff. However, James Webb’s filming shows a sharp image that cannot be compared with the past Hubble filming. Among other things, the open cluster NGC 3324, captured by the most sensitive NIRCam near-infrared telescope camera in human history, reveals hundreds of thousands of previously hidden stars and numerous background galaxies.
Dubbed the “cosmic cliff,” these cosmic clouds are being created by stellar winds and intense stellar radiation from the young, hot stars of open cluster NGC 3324. The high energies of the stars are slowly eroding and sculpting the walls of the nebula, and this celestial phenomenon is truly spectacular.
First, the “steam column”, which appears to rise from the mountain-like portion, is actually a hot dust emanating from the nebula from hot ionized gas and strong ultraviolet light. The column blocks strong ultraviolet rays from young stars, and it can be seen that the upper cliff is gradually eroding due to the intense radiation and stellar winds of the newly born star.
At the upper center of the “ridge”, the dusty early star is ejecting a jet and effluent that appears to be gold in appearance, confirming that the gas and dust above are ejecting as interstellar material. The image above, taken from NIRCam, looks like a comet. Also, in the photo above, an unusually shaped “arch” that looks like a curved cylinder is identified.
In fact, early star formation lasts only about 50,000 to 100,000 years, making it difficult to capture. But the extremely sensitive and sophisticated spatial resolution of the James Webb Space Telescope makes it possible. (Go to high resolution image)
in the northwestern corner of the Carina Nebula
NGC 3324 Open Cluster Edge “Cosmic Cliff” NIRCam + MIRI Composite Image
NGC 3324 open cluster edge “cosmic cliff” at the northwestern corner of the Carina Nebula. NIRCam + MIRI composite image © NASA, ESA, CSA, STScI
The image above is a composite image of the Carina Nebula taken by the James Webb Space Telescope’s Near Infrared Camera (NIRCam) and Mid-Infrared Instruments (MIRI). The north and east compass arrows show the direction of the image when viewed from below, and the direction when viewed from above should be reversed. The scale bar is expressed in light years, the distance light travels in one year, and it takes about two years for light to travel the length of the scale bar, as shown in the image above.
The image above shows the invisible near-infrared and mid-infrared wavelengths converted into visible light colors. The letters listed in different colors below the photo indicate the NIRCam and MIRI filters that were used to collect the light. The color of each filter name is the color of visible light used to indicate the near and mid infrared passing through that filter, and is a composite of individual exposures.
Looking into space through MIRI’s eyes brightens up young stars and dusty planet-forming disks, compared to NIRCam, which had exceptionally sharp resolution and unprecedented sensitivity, revealing numerous previously hidden stars and background galaxies. shines They appear pink and red. MIRI uncovers structures buried in dust and finds stars through massive jets and powerful outflows. This makes it easier to observe the early stars.
In particular, in NIRCam, the jets and emissions of the above early stars that look like comets appear to be cones emanating from a newborn star surrounded by dust using MIRI. In addition, MIRI can be used to detect hydrocarbons and other compounds. MIRI is also able to capture interstellar mass ejecting from the top center of the ridge, allowing a closer look at the dust surrounding the star responsible for this phenomenon. Also in the image above, you can see an unusually shaped arch that looks like a curved cylinder, as in the image of NIRCam. (Go to high resolution image)
“Interpretation of First Observations of the James Webb Space Telescope” Series Guide
About The Deep Field: James Webb’s Deep Field Was So Beautiful – Part 1
About the Deep Field: James Webb’s Deep Field Was So Beautiful – Part 2
Exoplanet Related: Discovery of Water in the Atmosphere of a Hot Gas Planet
The Death of a Star: A Closer Look Around a Dying Star – Part 1
The Death of a Star: A Closer Look Around a Dying Star – Part 2
Star Birth Related: Carina Nebula’s “Cosmic Cliffs” Revealed in Detail
Galaxy Related: How galaxies evolve – Part 1
Galaxy Related: How galaxies evolve – Part 2
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