The telescope has made thousands of observations with its 2.4-meter telescope, delivering breathtaking revelations about the size, age, expansion and evolution of the universe. Along with the birth and death of stars, the formation of planets, and many hidden wonders have spilled over into our own solar system. It’s fair to say that no other observatory, on the ground or in space, has revealed more about the cosmos than Hubble.
The James Webb Telescope’s mirror is much larger than Hubble’s at 6.5 meters and can collect more than five times the amount of light, allowing it to probe the distances and scales of the universe where Hubble cannot see. than darkness.
Telescopes allow us to go back in time because it takes time for light emitted by distant objects to reach us. Hubble captured images of distant galaxies as they appeared around 13.5 billion years ago, when the universe – which Hubble itself determined to be 13.8 billion years old – was still in the early stages of galaxy formation.
The James Webb Telescope will look deeper and deeper into the past, observing nascent galaxies as they were only 200 million years after the universe was born during the Big Bang.
Within our galaxy, it will probe giant molecular clouds to see like never before how primordial star systems and planets were formed, providing a glimpse into how our own solar system and planet were born.
And even closer to home, NASA’s new flagship space telescope will follow new discoveries of extrasolar planets by measuring their atmospheres, looking for signs of water and chemical telltales of possible extraterrestrial life.
NASA developed the James Webb Telescope in partnership with the European Space Agency and the Canadian Space Agency.
Not just a bigger Hubble
NASA’s new telescope is different from Hubble in several ways.
While Hubble focused on visible light emitted by stars, nebulae, galaxies and more, the Webb Telescope will specialize in infrared astronomy, collecting and analyzing lower energy electromagnetic radiation. Not only will this allow the study of cooler objects and materials, like the atmospheres of distant planets and the clouds of gas and dust that give rise to new star systems, it will open a window to an infrared universe. . Here, observations of the Earth’s surface cannot be accessed since the atmosphere blocks most wavelengths of infrared light.
Webb will not orbit Earth like Hubble does. Instead, it will encircle the sun at Earth’s “L2” Lagrangian point, where the gravitational pull of the Earth and the sun cancels out, forming a pocket of stable space where a spacecraft can roam indefinitely. The location offers a twofold advantage, keeping the observatory within communication range while keeping it away from intense electromagnetic interference from Earth.
Engineers designed Webb’s main mirror, which is almost three times the diameter of Hubble’s, to fit compactly into its launch rocket. The telescope’s light collecting apparatus includes 18 individual hexagonal mirrors that will be unfolded after launch during the month’s journey to its destination.
Operators expect the observatory to be ready for scientific observations about six months after launch.
What will we see?
In 1995, researchers using the Hubble Space Telescope made an observation that broadened our view of the universe.
They focused Hubble’s powerful eye on a patch of space where other observatories could only perceive darkness. The telescope zoomed in on a patch of the sky no larger than Franklin Roosevelt’s eyeball on an area of a dime and captured an image now known as the “Hubble Deep Field”.
This famous image revealed more than 3000 distant galaxies, never seen before. From this image and others like it, astronomers were able to estimate that there are approximately 2,000 billion galaxies in the observable universe.
Imagine what the much sharper eye of the James Webb Space Telescope will reveal about the cosmos.