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About 390 light-years away in the constellation Ophiuchus (Latin: Ophiuchus), there is a special region near the star Rho Ophiuchus that represents a veritable stellar hotbed. It’s the closest Star Forge to us. The James Webb Space Telescope (JWST) recently captured near-infrared images at five different wavelengths. The shortest wavelengths of 1.9 and 2.0 µm are designated blue and light blue respectively, cyan represents 3.4 µm, yellow represents 4.4 µm and red represents 4.7 µm. The recording is therefore a false color image. The displayed region extends over a distance of 0.7 light-years.
To the right and above the center of the image are numerous jets of reddish gas emanating from very young stars. They are in the process of being released from the gas and dust cocoons in which they formed. A total of 50 young stars – each with a maximum mass of one Sun – can be detected in this star cluster. The gas jets consist mostly of molecular hydrogen, which is shot toward the rotation poles of the young stellar bodies. Such phenomena are relatively short-lived. It indicates that the stars in question have not yet taken their place on the main sequence of the Hertzsprung-Russell diagram. This stage of development is called the T-Tauri stage. It is named after the prototype of the variable star T in the constellation Taurus. The dark area near the center of the image is a dense cloud of dust, which even the James Webb Space Telescope cannot see. It contains protostars that are still in an early stage of evolution and still collecting matter from their surroundings.
The bright region on the left below the center of the image was created by star S1, which has a mass much higher than that of the Sun. It is much hotter than our central star, and therefore emits significantly more radiation. It has already largely melted the surrounding envelope of gas and dust, and is generating powerful stellar winds that blow the cloud further apart. The yellow clumps of gas and dust around S1 contain large amounts of organic molecules, including polycyclic aromatic hydrocarbons, whose molecular structures contain rings made of carbon atoms. Such molecules are found in almost all regions of young star formation.
The area of sky surrounding Rho Ophiuchi appears very colorful in visible light, so it is often photographed by amateur observers. The star that gives it its name is located above the section of the image shown here in the rather blurry constellation Ophiuchus.
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