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Stephan’s Quintet (NIRCam + MIRI Imaging)

Stephan’s Quintet is a group of five galaxies, four of which (on the right) are about 90 million parsecs from Earth. The topmost galaxy, NGC 7319, harbours a supermassive black hole that is pulling in stellar material around it.Credit: NASA, ESA, CSA, and STScI

The views of the Universe just keep getting better. NASA’s US$10-billion James Webb Space Telescope released four new scientific images on 12 July, including newborn stars sparkling through dramatic ‘cliffs’ of gas, and galaxies interacting in an intricate cosmic dance. A day earlier, astronomers had marveled at its very first image, a mind-boggling deep dive into the distant Universe.

Webb observes the cosmos in infrared wavelengths, which gives it a different view than many other observatories, such as the Hubble Space Telescope. Webb’s 6.5-metre-wide mirror is the largest ever launched into space, and the combination of the large mirror and its infrared detection capabilities allow Webb an unprecedented view of many astronomical phenomena.

That includes stars and shock waves generated as galaxies collide in the group of five known as Stephan’s Quintet, 90 million parsecs away in the constellation Pegasus. The images that Webb collected of the galaxy grouping reveal millions of young stars forming as gas and dust collide, as well as sweeping tails left by one of the galaxies, NGC 7318B, as it storms its way through the cluster. “It really shows the type of interaction that drives the evolution of galaxies,” says Giovanna Giardino, an astronomer with the European Space Agency.

NIRCam Image of the “Cosmic Cliffs” in Carina

The cosmic cliffs is a star-forming region in the Carina Nebula that is roughly 2,330 parsecs away. Webb captured this image in exquisite detail, showing bubbles, cavities and protostellar jets, formed by interstellar wind, intense radiation and gathering dust from newborn stars.Credit: NASA, ESA, CSA, and STScI

Other cosmic action appears in a new Webb image of the Carina Nebula, a star-forming region around 2,330 parsecs away. Big hot stars at the nebula’s center blast it with radiation, which carves out a gaseous cavity, ringed with dramatic peaks and valleys and dubbed the ‘cosmic cliffs’. Webb’s infrared capabilities permitted it to peer through dust that often cloaks this view for other telescopes. The observatory also revealed brilliant pinpricks of light in the nebula that are newborn stars. “There’s just so much going on here — it’s so beautiful,” says Amber Straughn, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Side-by-side comparison shows observations of the Southern Ring Nebula in near-infrared light and mid-infrared light.

The Southern Ring Nebula, located around 770 parsecs away, is formed by a pair of stars, one of which is dying and shedding dust and gas. Webb captured images of this nebula with two of its instruments: on the left, the near-infrared camera, and on the right, the mid-infrared instrument. The latter reveals the second star in the pair surrounded by dust for the first time.Credit: NASA, ESA, CSA, STScI, and the Webb ERO Production Team

On the opposite end of the stellar lifecycle is the Southern Ring Nebula, a glowing shell of gas and dust that was ejected by a star near the end of its life. Located around 770 parsecs away in the constellation Vela, the nebula displays rings of material, each ejected during a particular episode from the dying star. Webb’s high resolution allowed it to pick out intricate detail in these shells, as well as revealing a second star that orbits the main one. Together, those stars light the surrounding nebula like the Sun shining through patchy clouds.

Exoplanet WASP-96 b (NIRISS Transmission Spectrum)

Webb captured this spectrum of water in the atmosphere of the exoplanet WASP-96b, a hot gas giant. From the spectrum, researchers calculated the atmosphere’s temperature: 725°C (1350°F).Credit: NASA, ESA, CSA, STScI

Perhaps the least visually striking, but most scientifically compelling, image of NASA’s release is a chemical analysis, or spectrum, of the atmosphere of a distant planet known as WASP-96b. This planet is around half the size of Jupiter but orbits its star in just 3.5 days, meaning that its surface is extremely hot. Webb observed the planet as it passed across the face of its star, such that the starlight travelled through the planet’s atmosphere and enabled scientists to chemically analyze it. They spotted the fingerprint of water in the atmosphere of WASP-96b, suggesting that it is a truly steamy place.

It is the first of many exoplanet spectra that Webb will gather — in a research field that did not even exist when the telescope was being dreamed up, before any planets were known beyond the Solar System. And yet exoplanets now promise to be one of Webb’s most significant areas of discovery. Studies of spectra from these planetary bodies can reveal how life-friendly other worlds might be. “We can use this tool to see something, because people want to know, when are we gonna see another Earth?” says John Mather, Webb’s senior project scientist at Goddard.

All four of the telescope’s instruments have been fully commissioned and are now doing science. Astronomers are thrilled to have this new and hugely capable observatory, which promises to enable discoveries on a wide range of astronomical phenomena. “We’ve got this humongous laboratory to learn about different aspects and different areas of the Universe,” says Hannah Wakeford, an astronomer at the University of Bristol.

Webb is a collaboration between NASA, the European Space Agency, and the Canadian Space Agency. It launched in December after more than two decades of development, and observes the Universe from a spot in space on the other side of the Moon, 1.5 million kilometres from Earth.

Additional reporting by Max Kozlov and McKenzie Prillaman.



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