James Webb Space Telescope
The James Webb Telescope, the successor of the Hubble Space Telescope, was launched into space on December 22, 2021, with the purpose of explaining the existence of the universe. It is the most powerful telescope ever built and is named after James E. Webb, who oversaw the first crewed missions to space.
He believed that the space program was more than a political race; his vision was that NASA balanced human space flight and science at its best, shaping and strengthening the aerospace industry. Born on October 7, 1906, James E Webb was the second appointed administrator of NASA.
Later in 2002, the Next Generation Space Telescope (NGST) was renamed the James Webb Space Telescope to honor his legacy. In addition, Webb was a crucial figure in the construction of the Operated Spacecraft Center, later renamed as Johnson Space Center in Houston.
The main objective of the telescope is to detect the infrared and ultraviolet rays emitted from space to aid in unraveling the mysteries surrounding the composition of the universe. Its other goals include the following:
- To gather information about our solar system and investigate the different galaxies formed around 13.5 billion years ago from the signals collected.
- To observe and analyze the planets, black holes, galaxies, stars, and the structure of the entire universe.
- To learn about the evolution and the atmosphere of our planets and exoplanets.
- To analyze the chemical composition of the universe, as different chemical elements absorb light at different wavelengths and the data collected helps us study their formation.
Design and Engineering
The launch vehicle, the image processing, the electromechanical systems, the cooling systems, the mirror, and the sun shield of this telescope are all revolutionary mechanics.
- In addition, the telescope launched from the French Guiana located at the equator gives the telescope an extra push towards the final destination.
- The Infrared detectors used to collect the faint lights coming from the galaxies were a concept from Professor Mark McCaughrean, Ph.D. from Edinburgh, Scotland. The telescope uses the sensors to formulate 2000 x 2000 pixel imaging for clear resolution.
- To operate, the backside of the telescope needs to perform at -233 degrees celsius. Hence the telescope carries a massive shield on the back like a tortoise which blocks a tremendous amount of heat. Kapton, a high-performance plastic that is light and transparent, is used and coated with 100nm thick aluminum that gives a reflective surface to the shield, enabling it to block the radiations of heat. This shield is the sizer of a tennis court, and after reaching space, it takes three additional days to unfold. Ripstop seams are molded to the shield to prevent tears while extending.
- Eighteen hexagonal golden mirror segments every 6.5 meters consist of a beryllium surface plated in gold. This mirror is one is the most fascinating parts of the telescope. Beryllium is a lightweight metal that helps reduce weight. It is stiff but not reflective, while the gold plating helps to reflect infrared radiation. Each mirror can adjust its position with the help of motors in the beryllium layer for its proper rotation.
The James Webb Telescope is projected to reach the Lagrange point 2 and is estimated to take exactly 10 years to complete its primary goals. It cost 10 billion dollars to manufacture the enormous telescope, and the Cryocooler cost 150 million dollars.
This telescope will hopefully help us unravel the truth about black holes and communicate with possible alien communities living at the far end of the galaxy. In contrast to the Spitzer telescope, this telescope will give more clear resolution images from the furthest reaches of the universe.
Some Major Space Telescopes
1. James Webb Telescope
To collect information and infrared radiation for a detailed study of the galaxy, aimed to travel to the Lagrange point 2.
2. Hubble Space Telescope
To travel through space and gather visible UV radiations to detect and study cosmic objects.
3. Chandra X-Ray Observatory
It is considered the world's most powerful x-ray telescope; it traveled to inspect the x-rays emitted from the strangest objects found in space.
4. Spitzer Space Telescope
It was the first telescope to provide intel about an existing exoplanet; it travelled throughout space to scan different exoplanets and comets.
5. Kepler Mission
NASA's planet poaching telescope searched for every possible earth-like planet in space.
Comparison with Hubble Telescope
- The James Webb Telescope won't be in orbit around the earth like Hubble, and it will be launching to a destination 1.5 million kilometers away from the planet called Lagrange point 2.
- The collecting area of the Webb will be 5.5 times larger than the Hubble's circular glass mirror.
- Hubble needs humans to service it, like when they repaired its optics because of an issue with blurry images. But, unfortunately, Webb is auto-adjusting and is too far away from the earth.
- Hubble can transmit only the visible radiations, but the Webb can receive infrared and UV radiation because of its sensors.
- The Webb's mirrors are 62% lighter and three times wider than the Hubble, enabling us to study further aspects of space.
- The Hubble project was estimated at around 2 billion dollars while the Webb's exceeded the 10 billion mark.
2. Goddard space flight center
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2021 Shubham Kadariya