Launched on 25th December ,2021, James webb space telescope has been much in the news since then. What are its unique features which make it superior to its predecessor space telescopes? What are the key goals of this mission? What potential benefits does it hold for the human race? UPSC CSE Main 2022 GS paper 3.
Answer
The James Webb Space Telescope is a space telescope designed to conduct infrared astronomy and to observe the most distant and faint objects in the universe. It will complement and extend the discoveries of the Hubble Space Telescope, with longer wavelength coverage and greatly improved sensitivity. Its main goals are to:
Seek out light from the first stars and galaxies that formed after the Big Bang
Learn more about the formation and evolution of galaxies
Study the origins of life and look for signs of life on planets around other stars
Look inside dust clouds where stars and planetary systems are forming today
Some of the unique features that make it superior to its predecessor space telescopes are:
It has a large infrared telescope that has an approximately 6.5-meter primary mirror, which is about three times larger than Hubble's mirror. This allows it to collect more light and see fainter objects.
It has a deployable sunshield that protects the telescope from the heat and light of the Sun, Earth, and Moon. The sunshield is made of five layers of thin material that keep the telescope at a very cold temperature of under 50 K (-370 °F). This is necessary for infrared observations, which can be easily affected by heat.
It has a folding segmented mirror that can be adjusted in orbit to achieve the best focus and image quality. The mirror is made of 18 hexagonal segments that are coated with gold to reflect infrared light.
It will orbit the Sun about 1 million miles from Earth at a point called the second Lagrange point, or L2. This is a stable point in space where the gravity of the Sun and Earth balance each other. This allows Webb to stay aligned with Earth as it orbits the Sun, and to always have a clear view of the sky.
The potential benefits of this mission for the human race are:
It will help us understand our cosmic origins and how we fit into the grand scheme of things. By looking back in time to see the first light in the universe, we can learn how everything we see today came to be.
It will help us explore the diversity and possibility of life in the universe. By studying planets around other stars, we can learn how common or rare life is, what conditions are needed for it to emerge and thrive, and whether there are any signs of intelligence or civilization out there.
It will inspire us with awe and wonder at the beauty and mystery of the cosmos. By capturing stunning images and spectra of galaxies, stars, planets, and nebulae, it will reveal new aspects of nature that we have never seen before, and challenge us to ask new questions about our place in space.