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Finally... The JWST's First Images Are Here And They Are... UGH! Mesmerising.

After 25+ years of designing, planning, building, launching, unfolding and testing, the first images by the James Webb Space Telescope have been released, and reveal the full promise and spectacular nature of what this mighty observatory can achieve.

The James Webb Space Telescope is a space telescope designed primarily to conduct infrared astronomy. (What is infrared astronomy? Keep reading) As the largest optical telescope in space, its greatly improved infrared resolution and sensitivity allows it to view objects too old, distant, or faint for the Hubble Space Telescope.

The huge 6.5-meter mirror, made up of 18 hexagonal small gold-plated mirrors, gathers a huge amount of light and provides a sharp view of the cosmos, so the images are clean and high-resolution, and the battery of filters means we can convert them into color images to please our eyes and inform our brains.

Okay now what is infrared astronomy right? Infrared astronomy is a sub-discipline of astronomy which specializes in the observation and analysis of astronomical objects using infrared radiation.

Now don't keep your eyes and brain waiting. Let's go!

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SMACS 0732

The first JWST Deep Field image shows SMACSJ0723.3-7327: a galaxy cluster, a collection of hundreds of galaxies orbiting their mutual center of gravity. It lies very roughly 4.5 billion light-years from Earth.

You might be thinking, what's exactly going on in this picture. The sharp objects with diffraction spikes are all stars in our own Milky Way galaxy, probably hundreds of thousands of light years away. But every fuzzy thing you see? Those are entire galaxies, all like billions of light years away. And there are thousands of them in this image. Thousands.

Including the smallest, faintest objects ever observed. Webb's image is approximately the size of a grain of sand held at arm's length, a tiny silver of the vast universe.

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WASP-96B

1,100 or so light-years from Earth is a Sun-like star, but is a very un-solar-system-like exoplanet orbiting it. That planet is WASP-96b, a hot jupiter with about the same size as our own Jupiter, but half the mass, and it orbits the star once every 3.4 days at a distance of only 7million kilometers!

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NGC3132, THE SOUTHERN RING NEBULA

NGC 3132 is a planetary nebula, the gas and dust ejected away from a star that was once much like the Sun but then ran out of fuel in its core and died. The central star expanded into a red giant, blew away thick layers of material, then exposed its hot core which then blew less dense but hotter and faster gas into that previously ejected stuff. This carved a huge expanding bubble into it.

The star in the center is actually two stars, a binary system. The second star is buried in so much material it's not visible in shorter wavelength. The binary motion may be what shaped the nebula, their orbits around each other sculpting the way the gas was ejected.

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STEPHEN'S QUINTET

300 million light-years from Earth is Stephen's Quintet, a small clutch of interacting galaxies... well, four of them are. The fifth, NGC 7320 (left) is actually a foreground galaxy coincidentally aligned with the more distant group.

The NIRCAM image shows cool gas and dust in the group, including some flung out NGC 7318 a and b (center), two galaxies deep in the process of colliding. The gravity of the two galaxies can send out streamers of material, called tidal tails, which then cools and forms stars.

The MIRI image shows something more: The center of NGC 7139 (top) is very bright, and that means we're seeing the tremendous light from a supermassive black hole, eagerly gobbling down gas and dust in the galaxy's core. Images like this (and spectra) can tell astronomers vast amounts about this process, like how massive the black hole is, how much material it's eating, what happens to that matter as it falls in, and how some of it is blasted away in long, thin beams of jets that can fly away from the black hole at speeds a decent fraction of the speed of light!

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CARINA NEBULA

In the southern constellation of Carina is a ridiculously huge, sprawling cloud of gas and dust called Carina Nebula, It's very roughly 7,000 light-years from Earth, and one of the Milky Way's most active star forming factories.

In this JWST NIRCAM (Near Infrared Camera) image you can see a very handful of very massive, luminous stars at the top. These blast out radiation and winds of subatomic particles that eat away at the gas and dust, evaporating them. This leaves behind a wall of material - that bright, scalloped horizontal line - with dense material below and less dense, hotter material above. It looks almost like a mountain ridge or, approximately, a cloudbank.

In the MIRI (Mid Infrared Image) we can see the effect of this: Dozens of stars are being born there, some blowing away their birth gas, others still deeply enshrouded in the materials that are forming them.

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After seeing SMACS 0732 image we can think about how big the sky is compared to that grain of sand. This entire sky can fit something like 25 million such images in it. This image is a tiny, tiny fraction of the Universe, yet it shows wonders and delights by the thousands.

What will we see when JWST stares at one spot for as long, how many tens of thousands of distant galaxies will be revealed? How many hundreds of billions more await our investigation?

Once you grasp that, you'll glimpse why astronomers do what they do.

It's an immense Universe, and we want to understand all of it. With JWST we have taken a big step forward in doing just that.