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The image is divided horizontally by an undulating line between a cloudscape forming a nebula along the bottom portion and a comparatively clear upper portion. Speckled across both portions is a starfield, showing innumerable stars of many sizes. The smallest of these are small, distant, and faint points of 
light. The largest of these appear larger, closer, brighter, and more fully resolved with 8-point diffraction spikes. The upper portion of the image is blueish, and has wispy translucent cloud-like streaks rising from the nebula below. The orangish cloudy formation in the bottom half varies in density and ranges 
from translucent to opaque. The stars vary in color, the majority of which, have a blue or orange hue. 
The cloud-like structure of the nebula contains ridges, peaks, and valleys – an appearance very similar to  a mountain range. Three long diffraction spikes from the top right edge of the image suggest the presence of a large star just out of view.
NASA, ESA, CSA, Webb ERO Production Team
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STScI

How is the Webb telescope different from the Hubble? The images tell the story

The James Webb Space Telescope is not a replacement for the Hubble Space Telescope. It's a successor inspired by Hubble’s previous results.

It's the next step in answering the question: “What’s up there?”

And it's not just “better” the way a 2022 digital camera is better than one from 2005.

Hubble produces images primarily by looking at light in the visible and ultraviolet spectrums of light — that is to say light that humans can see and light with shorter wavelengths. Webb creates images in the infrared and near-infrared spectrum — light with wavelengths longer than light visible to humans.

Southern Ring Nebula SideBySide
Space Telescope Science Institut/NASA, ESA, CSA, STScI, Webb ERO
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STScI
Hubble (left) Webb (right): The Southern Ring Nebula as captured by Hubble in 2005 (left) and Webb in 2022 (right). This nebula is formed from layers of gas and dust cast off by a collapsing star over thousands of years. Webb’s image throws these rings into sharp relief.

This is an important difference due to the way light changes as it travels across the universe.

Without getting too deep into the weeds of general relativity, the light is stretched as it travels. This stretching increases the wavelength of the light, moving it from the visible spectrum toward infrared. By being able to see more of the infrared spectrum, Webb can see objects that are more distant than Hubble can.

"Cosmic Cliffs" in Carina Nebula Hubble Webb Side by Side
Hubble Heritage/Space Telescope Science Institut/NASA, ESA, CSA, STScI, Webb ERO/Acknowledgement: N. Smith et al. (JHU)
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STScI
A portion of the “Cosmic Cliffs” of the Carina Nebula as captured by Hubble (top) and Webb (bottom). The infrared image from Webb allows us not only to see far greater detail, but to pierce through the nebula’s clouds and see numerous objects beyond.

To complicate things just a bit more, when we see objects farther away, we are actually seeing older objects. This is because light takes time to travel, so by the time it reaches us here on Earth we are not seeing a distant star as it is today, but as it was thousands or millions of years ago. For example, the Cosmic Cliffs region of the Carina Nebula (top of the page) is roughly 7,600 light years away from us. So that image isn’t what the cliffs look like today, but what they looked like 7,600 years ago when that light left the nebula.

This means Webb is essentially letting us see further back in time. As one NASA article put it: “Essentially, Hubble can see the equivalent of 'toddler galaxies' and Webb Telescope will be able to see 'baby galaxies.'"

Hubble Cashes in Abell’s Richest Cluster
Hubble/NASA, ESA, CSA, STScI, Webb ERO Production Team
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STScI/ESA/Hubble
A deep field image captured by Hubble (left) and by Webb (right). This is the same region of space, but Webb’s infrared imaging shows many more objects. The redder the object in the image, the further away it is, and the further back in time we are looking when we view it.

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Tyler Russell is a Visuals Journalist, splitting his time between daily news photography and video content for digital and TV. He joined Connecticut Public in 2013 as an instructor in the Education Department and moved onto the Visuals Team when it was formed in 2019.