James Webb: What does the ‘star nursery’ image reveal? – 07/13/2023 – Science

Happy scientific birthday to the James Webb Space Telescope. In July 2022, the world saw the first images made by the super observatory – WST, in its acronym in English.

To commemorate the anniversary, the US space agency, Nasa, released a spectacular image of one of the most photographed parts of the sky.

This is the Rho Ophiuchi nebula complex, which is the closest star-forming region to us in space, at a distance of 400 light-years from Earth.

What Webb shows us is just a small part of this dense region of gas and dust, which is what you’d expect to see, given the telescope’s astounding resolution.

The entire image is about half a light-year across, or 4.7 trillion kilometers.

The eye is immediately drawn to the white nebula in the center-left region of the image, where a relatively young star — a few million years old — called S1 lights up all around.

Below it, you can see a red structure that extends horizontally across the entire image. This is the flow of material from a protostar called VLA1623.

Very young stars—ages measured in mere thousands of years—pull hydrogen gas and dust in on themselves as they grow.

But the dynamics involved mean that some of that material will also be ejected to collide and illuminate the nearby environment.

VLA1623 is one such nascent star. It is buried deep within the structure and is invisible to Webb’s infrared “eyes”.

We know the star is there, however, because telescopes sensitive to radio wavelengths have already detected it.

They also found two or three other similar protostars in the immediate vicinity, which are likely contributing to the image’s red contortions.

Once you realize what is happening in the photograph around VLA1623, you can pick out similar flows in other parts of the horizon in the same image. There are many details, which just illustrates how productive this region of space is.

JWST is a joint project of NASA and the European (Esa) and Canadian (CSA) space agencies.

It launched on December 25, 2021, but it took engineers six months to assemble the observatory and test all the systems.

On July 12, 2022, the first color images taken by the equipment were presented.

The telescope’s main objective is to track the first stars to shine in the Universe more than 13.5 billion years ago. Over the past 12 months, it has already demonstrated that galaxies of stars formed much earlier and matured much faster than previously thought possible.

The telescope also has other projects in the works. One is to show the details of how stars are created and how they spawn planets — which is why Rho Ophiuchi is a fascinating target for the most powerful observatory in space.

“There is so much going on in this spectacular image, as young stars shed vibrant colors in the clouds of gas and dust they are emerging from,” commented Professor Mark McCaughrean, senior adviser at Esa.

“Much of the bright red emissions come from jets of gas flowing at high speed from an unseen protostar, VLA1623. It is such a young star that many Stone Age cave paintings predate it,” he compared.

“JWST will not only revolutionize our view of how galaxies were born in the early universe, but also how stars and planets are made today, much closer to home in our own Milky Way Galaxy,” the astronomer told BBC News.

To underline what Webb represents, the image above was captured by NASA’s now-retired Spitzer Space Telescope.

It shows the same Rho Ophiuchi complex.

Spitzer, like Webb, was sensitive to infrared light. It was a very capable setup, but with a primary mirror only 85 centimeters in diameter.

With that, he could never have achieved the kind of detail we see now with Webb’s 6.5 meter primary mirror.

This text was originally published here.