NASA’s James Webb Space Telescope, the largest and most powerful space telescope ever built, is now about a million miles from Earth, spinning from one place in the sky to another as it studies the target-rich environment that is our universe. The first handful of images were released this week.
They are stunning. They are also loaded with information about the universe, the interactions of galaxies, and the birth and death of stars.
Still, these images can be enigmatic to the casual observer who doesn’t have a degree in astrophysics. What exactly are we looking at?
Let’s take a closer look.
The deep field
There are many galaxies there. It was the first image released publicly that demonstrated the telescope’s power to capture extremely faint infrared light emitted during the universe’s first billion years. The image is centered on a galaxy cluster more than 4 billion light-years away, meaning its light was emitted roughly when the sun and Earth were formed. The galaxies in the cluster appear as creamy white blobs.
These galaxies collectively create a powerful gravitational warp in space that acts like a lens, magnifying and distorting more distant objects. This results in mirror galaxies like the one in the upper right of the image, which NASA astronomer Jane Rigby calls Laffy Taffy.
In another part of the image, the lens has turned one galaxy into two mirror galaxies.
Light comes in many wavelengths along what is called the electromagnetic spectrum. Humans see in a narrow band known as the “optical” part of the spectrum. The Webb telescope collects light emitted in the infrared range – long wavelengths that are largely inaccessible to the Hubble telescope and completely invisible to us.
James
Web
space
Telescope
Sources: NASA; European Space Agency;
Space Telescope Science Institute
WILLIAM NEF/WASHINGTON POST
James Webb
Space telescope
Sources: NASA; European Space Agency;
Space Telescope Science Institute
WILLIAM NEF/WASHINGTON POST
James Webb Space Telescope
Sources: NASA; European Space Agency; Space Telescope Science Institute
WILLIAM NEF/WASHINGTON POST
Webb’s team scanned dozens of the reddest — the most distant — galaxies in this image and found that one of them — a small, pixelated blob — emitted its light about 13.1 billion years ago, just 700 million years after the big Bang. (Distances to such objects are inferred from their “redshift” – the degree to which the light has been streeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee you the expansion of space itself.)
The telescope obtained a spectrum of the galaxy showing signs of oxygen, hydrogen and neon. Rigby said this kind of observation would shed light on what was going on in the first billion years of the universe: “We really don’t know at all how big these galaxies were, how many of them there were.”
Southern Ring Nebula
Stars like our sun are nuclear fusion reactors that are remarkably stable over billions of years. But even they get old. This image shows what happens when a star dies. It ejects matter in its throbbing death throes.
These clouds of gas and dust, including complex molecules, are the raw material for stars and planets that have not yet formed.
NASA released two images, one in the near-infrared (relatively close to the “visible” part of the spectrum) and one in the mid-infrared (further out the spectrum).
In the near-infrared region, the material forms a ring of foamy gas and dust, with hot, ionized gas dominating the central region. Light rays exit through holes in the outer ring.
Only one star is clearly visible in the center. But it is a binary system – two stars bound together by gravity.
In the mid-infrared range, we see both. The dying is weaker. The telescope reveals that it is shrouded in dust.
Our sun will look similar to this star in 5 billion years, explained Klaus Pontoppidan, a Webb project scientist at the Space Telescope Science Institute.
“This is the life cycle of stars,” Pontoppidan said. “It’s the end for this star, but it’s the beginning for other stars and other planetary systems.”
The image includes an intriguing slash on one shoulder, which astronomers realized was a distant galaxy. Although it is a huge three-dimensional structure with billions of stars, we look at its edge as if we were watching a frisbee spinning away from us.
Stefan’s Quintet
There is a lot of space in the image.
There are stars from our own galaxy – which means they are in the foreground, from a cosmic point of view.
The foreground stars in all Webb images can be identified by their “diffraction spikes,” which are an artifact of the telescope’s design. The diffraction spikes in these images serve as a sort of Webb Telescope watermark.
In the middle distance is what appears to be a quintet of galaxies.
The one on the left is not part of the group, but rather in the foreground, about 40 million light-years away.
The telescope can make out individual stars in the foreground galaxy.
Many are aging “red giants” near the end of their lives, with well-documented properties that help astronomers estimate their true brightness and distance. Such observations could improve the model scientists use to estimate the distance to objects across vast stretches of space.
The other four galaxies are about 290 million light years away. Two merge. Gravitational interactions of galaxies have sent streams of star-forming gas and dust into intergalactic space.
Strikingly, this image, like Deep Field, contains countless galaxies scattered across the background. Look closely and you will see wonderful, very distant spiral galaxies similar to our own Milky Way.
The large galaxy at the top has a supermassive and highly active black hole at its core, feeding on its surroundings. A black hole itself does not emit light by definition, but its gravitational field charges nearby gas, causing atoms to collide with each other and generate enormous heat.
This black hole’s accretion disk glows with the energy of 40 billion suns, Rigby said: “Black holes don’t emit light, but their accretion disks sure do!”
Carina Nebula
Looks like a good place to walk! Complete with a sparkling sky full of stars. This nebula is a stellar nursery in our own galaxy.
“What appears to be a starry night sky is part of a giant bubble carved out of the cloud by the ultraviolet radiation and stellar winds from extremely massive, hot, young stars that have already formed,” said astronomer Amaya Moreau-Martin of Space Science telescope institute.
Streams of ionized material flow to the top of the frame.
Webb can see shock waves caused by newly ignited stars forming in the cloud. Their environment is hostile because the same process that destroys the cloud can stop star formation.
The Hubble Space Telescope had previously studied this part of the sprawling Carina Nebula, and Webb’s team knew that the sharply defined boundaries between the dust cloud and the “open sky” would make for a stunning image.
But it’s more than just beautiful space art, said Joseph DePasquale, who is part of the team that processed the images at the Space Telescope Science Institute in Baltimore.
“We knew, based on the Hubble image, that the landscape of this would look very much like a mountain range and the sky behind it. We knew it would be aesthetically impactful,” DePasquale said. “But also a lot happened in terms of physics. Webb can peer deeper into the clouds and reveal the mysteries of what’s going on.
About this story
This annotation was compiled with the help of many scientists and researchers, including: Jane Rigby of NASA’s Goddard Space Flight Center; Joseph DePasquale and Amaya Moro-Martin of the Space Telescope Science Institute and Garth Illingworth of the University of California, Santa Cruz.
Visual editing by Julie Vitkovskaya. Design and development by Garland Potts. Graphics by Aaron Steckelberg and William Neff. Photo editing by Tristen Rouse. Copy editing by Jeremy Hester.
Add Comment