James Webb: Supertelescope takes pictures of the star factory

The Stellar Arboretum is located about 200,000 light-years from Earth, in the Small Magellanic Cloud. In a fictional spacecraft moving at the speed of light, it would take 240 years to traverse this region of space.
NASA / ESA / CSA / STSCI / A.PAGAN
This is another great image from the new James Webb Superspace Telescope.
The image shows NGC 346, a region about 200,000 light-years from Earth where many stars are forming.
A near infrared webcam captures the knots, arcs, and filaments of gas and dust that fuel this stellar nursery.
NGC 346 is embedded in a satellite galaxy of our own, the Milky Way, called the Small Magellanic Cloud – and is used as a laboratory for studying star formation processes.
The agglomerate contains relatively low concentrations of elements heavier than hydrogen and helium.
See also:
James Webb discovers primordial galaxies from the early universe
See the image of the merger between two galaxies
The Super Telescope captures new images of the ‘ghost galaxy’
In this way, conditions reproduce, in a sense, those that existed much earlier in the history of the universe, when star birth was at its peak – a period known as the “cosmic dawn”, some three billion years after the Big Bang.
Previous space telescopes were able to detect the larger objects in this scene, but Webb’s, with its superior sensitivity and resolution, allows astronomers to pinpoint the smaller sources.
“For the first time, we can see the full sequence of star formation in another galaxy,” says Olivia Jones of the UK Astronomy Technology Center (UK ATC) in Edinburgh, Scotland.
“Previously, using Spitzer, which was one of NASA’s greatest observatories, we were able to detect the most massive protostars, which are about five to eight times the mass of our sun.”
“But with Webb, we have the sensitivity limits to go down to 1/10th the mass of the Sun. So we have the sensitivity to detect very low mass stars in the formation process, but also the precision to see how they affect the environment. And as you can see from the image, it’s a very dynamic environment.”
There is gas being activated in this image at temperatures up to 10,000 degrees Celsius. On the other hand, Webb also detects cold gas at -200°C.
Astronomers refer to “metals” when discussing all elements heavier than hydrogen and helium. It is the material needed to make planets.
Therefore, one of the big questions revolved around whether low metallic environments, such as NGC 346, had enough dusty material to carry out accretion (the accumulation of matter on a star’s surface through gravitational motion) and build up rocky worlds. .
Webb’s notes on the conglomerate indicate that it certainly has that potential. Even the smallest protostars detected in the image have disks of dust around them.
Incidentally, this proposed planetary formation was also possible at the beginning of the universe, in the cosmic twilight, as Margaret Mixner, an astronomer at the University Space Research Association in Maryland, USA, explains.
“The metallicity of the Small Magellanic Cloud is comparable to the peak age of star formation in the universe. This is when we’re essentially producing the most stars in the universe. And that’s very interesting because it means that there are likely to be planets around a large number of stars,” says the researcher.
The new image of NGC 346 taken by Webb was released at the 241st meeting of the American Astronomical Society in Seattle, USA.
He also announced that the telescope had discovered the first exoplanet – the name given to planets orbiting other stars.
The planet, officially named LHS 475 b, is roughly the same size as our own, measuring 99% the diameter of Earth.
Its existence was suggested by data from NASA’s Transiting Exoplanet Survey Satellite, but Webb was able to quickly dispel suspicions.
He observed the light from the parent star and was able to detect the drop in emissions when the planet passed in front of it, something that happened every two days.
This very short orbital period means that LHS 475 b is very close to its star and, as a result, is a few hundred degrees hotter than Earth.
Astronomers are trying to determine the possible composition of the atmosphere. However, it is possible that the planet may not have one.
“This planet could be an airless body that has lost whatever atmosphere it once had,” says Jacob Lustig-Yeger of the Johns Hopkins University Applied Physics Laboratory, also in Maryland.
But Webb’s data may also be consistent with a thick atmosphere of carbon dioxide with clouds at high altitudes — unlike Venus.
A paper detailing NGC 346 has been submitted to an academic journal for publication. It is currently available on the arXiv open access article repository.
– This text is posted at: https://www.bbc.com/portuguese/geral-64260360