Tabloids

Space observation just levelled up

By Nethmie Dehigama

By now, you have most likely seen the newly captured space images taken by NASA’s James Webb Telescope floating around social media. But why has it taken the astronomy community by storm? Here’s the breakdown for you.

What is the James Webb Telescope?

This telescope is the culmination of NASA’s 20-year project to launch a next-generation space observatory to succeed the Hubble telescope. It took $20 billion to build and is 100 times more powerful than Hubble. It is able to capture images of space billions of lightyears away. The telescope was launched into orbit in December 2021, and official operations began six months later. The telescope holds fuel that will help it last for 20 years.
Webb was designed to collect light across the entire red to mid-infrared wavelengths of light that are blocked by Earth’s atmosphere. And with its giant mirror and sunshade blocking infrared emitted by the sun, Earth, and moon, Webb can produce images of a sharpness never before achieved by any other telescope. Webb can also collect data on objects that reveal physical and chemical properties.
Note: A lightyear is a unit of length used to measure astronomical distances. One lightyear is equivalent to 9.46 trillion kilometres. In more technical terms, a light year is a measure of light travelling in a vacuum in one Julian year (365.25 days).

What’s so special about these images?

On July 11, NASA released five images taken by the James Webb Telescope.

Stephan’s Quintet – This is an image of five galaxies located 290 million lightyears away. The image revealed that two of the galaxies were in the process of colliding/merging with each other. Gas and dust heat up, creating new stars. The image also provides insight into how gravity behaves in outer space, as well as about dark matter – the mysterious “glue” that holds the universe together.

Carina Nebula – This is located 7600 lightyears away from Earth. Nebulae are basically clouds of gas and dust, some of which are formed by dying stars. This particular nebula is thought to be the most active star-forming nebula observed to date. The reason this image is special is that the telescope was able to capture just a tiny “cliff” of the nebula in great detail.

Southern Ring Nebula – This one reminds me of the Eye of Sauron. Also known as the Eight-Burst Nebula because it resembles a figure eight, it is about 2500 lightyears away. This image is highly special because previously it was only calculated that this nebula could be centred around a binary star system, i.e., two stars – but in this photo, the second star is finally observable.

Planet WASP-96b – Located just 1150 lightyears away, this gaseous planet is about half the mass of Jupiter. This planet revolves in close proximity to its home star – one revolution around it lasts only 3.4 Earth days. The image gives scientists a clearer idea of the clouds and haze that seems to surround it. 

Webb’s First Deep Field – this is the deepest image of the universe ever taken. You have probably seen this one the most online. The image captures galaxy cluster SMACS 0723, visible in the direction of constellation Volans. In the image, you can observe bluer galaxies – these are older ones. The redder ones are quite young and stars are still forming within them.

Imagine holding a tiny grain of sand at arm’s length while you face the night sky – that’s a rough estimate of what this image captures from the night sky that we see. And in this image, you can see thousands and thousands of galaxies, home to millions of stars and planets and other things in space. All that within that tiny grain. I don’t know about you, but I find it hard to even fathom the vastness of the universe, let alone how minuscule we are in comparison.
Some of these galaxies captured are 4.6 billion lightyears away. Since light takes time to travel, we are seeing these galaxies as they existed 4.6 billion years ago – things may be drastically different right now, but it will take another 4.6 billion years to see that. If alien life did exist – and let’s be honest, it would be quite egoistic to think we are the only life in this vastness – and they were looking back at us from within one of these galaxies, they will be seeing our solar system just beginning to form i.e., Earth did not even exist.
Not to mention, the image also has “faint dots” that are galaxies that are approximately 13.1 billion years old. That’s just 700 million years after the big bang (the formation of this universe). Scientists hope to derive insights into how the universe was formed through images like this.
What the Webb Telescope showed us is that apart from reasons for an existential crisis, there is no blank sky out there. The universe holds so many secrets. If you want to deep dive into these images, I highly suggest visiting www.abc.net.au. Take a tour through the James Webb images. 

PHOTOS © NASA, ESA, CSA, STSCI