homehome Home chatchat Notifications


James Webb vs Hubble: a mindblowing side-by-side comparison

James Webb's lens can peer in much greater detail and further back in time than any other telescope in the world.

Tibi Puiu
July 13, 2022 @ 3:29 pm

share Share

The Hubble space telescope was deployed into Earth’s orbit by the space shuttle Discovery more than 30 years ago. Since then, Hubble has produced spectacular images that have not only inspired and moved us to tears but also provided invaluable scientific insight, showing that the universe’s rate of expansion is actually accelerating due to some mysterious force known as dark energy.

Hubble is still an amazing tool for astronomy and will continue to do science for years to come — but scientists wanted more, which is why we now have the James Webb Space Telescope (JWST).

You’ve probably seen the first stunning images from JWST released starting this Monday. We’ve been truly spoiled, but how do these observations compare with Hubble’s?

Well, take this side-by-side deep field view of the SMACS 0723 galaxy cluster, showing dozens of galaxies 13 billion light-years away. The differences are obviously striking, including the much clearer gravitational lens effect that magnifies and bends light behind gravitationally massive objects.

Or this view of the Southern Ring Nebula, a vivid shell of gas and dust more than 1.3 light-years across expelled into space by a dying star. The JWB view (right panel) is popping with new stars and shows never-before-seen firmaments of gas and dust, showing how the dying star was pulsating matter during its last dying throes.

This unprecedented resolution is owed to the fact that JWB is about 100 times more sensitive than Hubble thanks to its much larger light-collecting mirror. But the biggest difference between the two is that Hubble primarily makes observations in visible and ultraviolet wavelengths, whereas the $10 billion JWST mainly sees in mid-infrared and near-infrared, though there is a bit of overlap between the two space telescopes.

Webb’s primary mirror has a diameter of 6.5 meters, compared to Hubble’s much smaller 2.4 meters in diameter. This means Webb can cover more than 15 times the field of view of Hubble. Credit: NASA.

JWST’s sensitivity to much longer wavelengths allows it to peer through dust clouds that would normally obscure stars, planetary systems, and distant galaxies from Hubble’s prying eye. This means JWST is so sensitive it can actually reveal the composition of far-away exoplanets’ atmosphere. It can also look much farther back in time and in much greater detail than Hubble because the most distant (and earliest) stars and galaxies are redshifted, meaning their light is pushed from optical and ultraviolet into the near-infrared. There is no other instrument other than the JWST that can see the very first galaxies form in the universe.

The JWST can see farther back in time than any other telescope. Credit: NASA, Ann Feild.

Notice how much clearer the stars are in the infrared view of Stephan’s Quintet, a grouping of five galaxies, compared to Hubble’s optical observation.

Similarly, the Carina Nebula is much richer seen through the lens of James Webb, with every new dot of light representing another star. Thanks to its infrared-sensitive instruments, Webb can clear away the cobwebs of gas and dust, showing not only hundreds of new stars, but also cavities and jets blowing from very young stars.

The Carina Nebula, as seen by Hubble (top) and James Webb (bottom). Credit: NASA.

This is just the beginning. We’re just scratching the surface and the JWST slowly starts to flex its muscles, it will reveal an increasing number of secrets of the universe. Stay tuned for more!

share Share

Cats Came Bearing Gods: Religion and Trade Shaped the Rise of the Domestic Cat in Europe

Two groundbreaking studies challenge the old narrative that cats followed early farmers into Europe.

Tiny Chinese Satellite Sent Hack-Proof Quantum Messages 12,900 Kilometers Through Space. Is a Quantum Internet Around the Corner?

The US and Europe are now racing to catch up to China.

The People of Carthage Weren’t Who We Thought They Were

The Punic people had almost no genetic ties to Phoenicians, even though the latter founded the great city of Carthage.

RFK Jr loves raw milk. Now, he's suspending milk quality tests due to Trump cuts

Imagine pouring a glass of milk for your child and wondering if it’s safe.

A Roman gladiator died fighting a lion in England and his 1,800-year-old skeleton proves it

It's the first-ever evidence of man-lion combat found in the Roman period.

This Surprising Protein Shift Could Add Years to Your Life, Study Finds

A global study ties plant protein to longer adult lives, but early life needs differ.

Scientists Create a 'Power Bar' for Bees to Replace Pollen and Keep Colonies Alive Without Flowers

Researchers unveil a man-made “Power Bar” that could replace pollen for stressed honey bee colonies.

First-Ever Footage Captures a Living Colossal Squid—And It’s Just a Baby

A century after its discovery, the elusive giant finally reveals itself on camera.

Ancient tree rings reveal the hidden reason Rome’s grip on Britain failed

Three scorching summers in antiquity triggered revolt, invasion, and a turning point in British history.

Oxford Academics Used a Human Skull as a Wine Cup—Until 2015

It sounds like a scene from gothic fiction, but it’s real.