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| James Webb Telescope (Photo by NASA) |
What is James Webb Space Telescope?
The James Webb Space Telescope (JWST) is a large, space-based observatory, optimized for infrared wavelengths and is being developed by NASA, the European Space Agency (ESA), and the Canadian Space Agency (CSA) as a successor of the Hubble Space Telescope as NASA's Flagship astrophysics mission.
The incurred cost for building this telescope alone is $10 billion.
Wondering what is so special about this telescope?
You are on the right webpage, we have answers for you here!
KEY FEATURES OF THE JAMES WEBB SPACE TELESCOPE (JWST):
JWST is optimized for increased infrared wavelengths unlike its predecessor Hubble Space Telescope, which means it has increased wavelength coverage and improved sensitivity.
Now, how does that help?
The greater wavelengths can enormously help in investigations across the fields of astronomy and cosmology, including observing some of the most distant events and objects in the universe, ranging from the formation of the first galaxies, and detailed atmospheric characterization of potentially habitable exoplanets to peering inside dust clouds where stars and planetary systems are forming today.
Infrared Radiations, visible light, and the James Webb Telescope:
- The wavelengths of infrared light are longer than those of visible light ranging from 0.4 to 0.7 micrometers.
- The infrared component of the electromagnetic spectrum is divided into three sections by astronomers: near-infrared (0.7-5 micrometers), mid-infrared (5-30 micrometers), and far-infrared (>30 micrometers).
- Webb's sensitivity will range between near-infrared and mid-infrared light which is pretty amazing, isn't it?
James Webb Telescope vs Hubble Space Telescope:
- The first key difference is the JWST's sensitivity to increased infrared wavelengths compared to the Hubble Space Telescope.
- The second key difference is that Webb has a 2.7 times larger primary mirror than Hubble which drastically increases its light-gathering capacity.
- The third and last but rather the most important difference is that Webb will be working 1 million away from Earth at the second Sun-Earth Lagrange point and will be unavailable for service while the Hubble was orbiting around Earth at a distance of 375 miles from Earth.
James Webb Telescope vs Large Ground Telescopes using adaptive optics:
- The Earth's atmosphere is nearly opaque and glows brightly at most of the infrared wavelengths that JWST will be observing, so a cold telescope in space is required. For the wavelengths that are transmitted to the ground, the Earth's atmosphere blurs the images and that is what causes stars to twinkle.
- Currently, adaptive optics systems can correct for this blurring only over small fields of view near bright stars functioning as reference beacons, allowing access to only a small fraction of the sky using ground telescopes.
- Artificial light beacons created with strong lasers may provide better access to the sky, but the technology to provide a wide field of view is still far in the future.
- Finding the earliest galaxies will require very low foreground light levels, ultra-sharp images over large areas, and studies at many infrared wavelengths, a combination of observing conditions only available from space.
JWST Launch Date:
James Webb Space Telescope will launch on December 24, 2021 at 07:20am EST.
Want to see a size comparison between the Webb and the Hubble?
Here is a great video by James Webb Space Telescope (JWST):
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