James Webb Space Telescope: How NASA saw 13.6 billion years back in time

NASA on Tuesday released stunning high-resolution photographs of the universe taken by its flagship James Webb Space Telescope. The equipment, which was developed over two decades at a whopping cost of $9 billion dollars, took the spectacular photos billed as the deepest pictures of the universe ever taken. The telescope, built under contract by  Northrop Grumman Corp, was launched on December 25, 2021. The best among the five photos taken is the deep field photo of a cluster of galaxies. The agency said at least one of the galaxies seen in the photograph is 95% as old as the Big Bang. The other four photos include --  two enormous clouds of gas and dust, fresh images of another galaxy cluster known as Stephan's Quintet and a Jupiter-sized exoplanet more than 1,100 light years away. 

Galaxy cluster

This cluster of galaxies is called SMACS 0723. This photo shows several stars and distant galaxies. If you scale it to the size of universe, according to NASA, all that was captured in the photo was the size of a grain held at arm's length from Earth. The image is a combination of several deep field photos taken over a combined time of 12.5 hours. The image showed the galaxy cluster as it appeared 4.6 billion years ago. This is because the light took as many years to reach the telescope. A concept called gravitational lens helped the scientists get a clear picture of the distant universe. What is gravitational lens? According to NASA, the powerful gravitational field of a galaxy cluster can bend the light rays from more distant galaxies behind it, acting as a magnifying lens. The galaxies appearing blue contain stars. The red ones are enshrouded in thick layers of dust. Green galaxies has hydrocarbons. The data revealed that one of the galaxies emitted light from 13.1 billion years ago. This means the scientists were able to see the galaxy as it was 13.1 billion years ago.

Photo credits: NASA

Cosmic cliff

James Webb Space Telescope captured this photo in infrared light. The photo that appears to be the landscape of mountains and valleys, is the edge of a star-forming region called NGC 3324 in the Carina Nebula. The sparking speckles are stars. The tallest peaks in this image are about 7 light-years high. One light-year is equal to 9 trillion kilometers. The steam rising from the celestial structure is in fact hot gas.

"Webb reveals emerging stellar nurseries and individual stars that are completely hidden in visible-light pictures. Because of Webb’s sensitivity to infrared light, it can peer through cosmic dust to see these objects. Protostellar jets, which emerge clearly in this image, shoot out from some of these young stars. The youngest sources appear as red dots in the dark, dusty region of the cloud. Objects in the earliest, rapid phases of star formation are difficult to capture, but Webb’s extreme sensitivity, spatial resolution, and imaging capability can chronicle these elusive events," NASA said in its release.

It said the photo would help scientists understand the process of star formation. The telescope will also help them understand what determines the number of stars that form in a certain region. It will also help them reveal the impact of star formation on the evolution of gigantic clouds of gas and dust.

In the photo, young stars appear pink and red.

NGC 3324 was first discovered by James Dunlop in 1826. It is only Visible from the Southern Hemisphere.

Stephan's Quintet

This is a group of five galaxies. This is the largest photo ever made by James Webb Space Telescope. It has 150 million pixels and is made from 1,000 separate images. This image shows sparkling clusters of millions of stars. The group is also called the Hickson Compact Group 92 (HCG 92). Actually, the group consists of only four galaxies -- NGC 7317, NGC 7318A, NGC 7318B, and NGC 7319. These are at a distance of 290 million light-years away from earth. The fifth, a bright yellow object below, is quite far from the other four.

"Tight groups like this may have been more common in the early universe when their superheated, infalling material may have fueled very energetic black holes called quasars. Even today, the topmost galaxy in the group – NGC 7319 – harbors an active galactic nucleus, a supermassive black hole 24 million times the mass of the Sun. It is actively pulling in material and puts out light energy equivalent to 40 billion Suns," NASA said.

French astronomer Édouard Stephan had discovered the cluster in 1877.

Dancing stars

The Southern Ring, or “Eight-Burst” nebula, is a planetary nebula – an expanding cloud of gas, surrounding a dying star. It is nearly half a light-year in diameter and is located approximately 2,000 light years away from Earth. Planetary nebulae are the shells of gas and dust ejected from dying stars. This photo shows the latest image of NGC 3121, which is 2,500 light-years away. "The dimmer star at the center of this scene has been sending out rings of gas and dust for thousands of years in all directions," NASA said in its release.

"This observation shows the Southern Ring Nebula almost face-on, but if we could rotate it to view it edge-on, its three-dimensional shape would more clearly look like two bowls placed together at the bottom, opening away from one another with a large hole at the center," it added.

Two stars are locked in an orbit. The first image shows the stars and their layers if light. The second image shows that the second star is surrounded by dust. As they orbit each other, they create asymmetrical patterns of gas and dust.