James Webb Space Telescope (JWST)

•  The National Aeronautics and Space Administration (NASA) have completed the construction of the James Webb Space Telescope (JWST) after more than 20 years of work.
• JWST is the largest-ever space telescope is expected to launch in 2018 following the in-depth testing.

About JWST:

• The telescope is designed to be far more powerful than Nasa’s famous but aging Hubble telescope, which has for 26 years revealed auroras and supernovas, mapped the sky for dark matter, and discovered billions of stars, galaxies and planets, including those in habitable zones.
• The James Webb Space Telescope (JWST) has a giant sunshield that divides the craft in two: one side facing the sun, which will power the device, and another to keep the instruments at an operating temperature of -220C, cold enough to minimize the effect of the telescope’s own heat on its observations. The telescope has a primary mirror more than five times larger than Hubble’s, meaning the JWST will be able to spot fainter, more distant objects.
• The JWST’s greater power will also mean that it can see planets in greater detail, letting scientists look for atmospheres, seasons and even weather or signs of life. Telescope will have “seven times the collecting area” of Hubble, and enough power to detect the body heat of a bumblebee on the moon.
• The new telescope will have infrared instruments, to reflect and collect infrared wavelengths, meaning it can look farther back in time – at the stars and galaxies hurtling away into the expanding reaches of the universe, from where it takes light billions of years to reach the Earth. Those stars’ light has stretched into wavelengths so red (“redshifted”) it has entered the infrared spectrum, past the range of Hubble’s view.
• The telescope will now be subjected to two years of tests before its planned launch in 2018. Unlike Hubble, it will be sent far from where astronauts could repair it, and it will first test the JWST for the “violent sound and vibration environments” of a rocket launch, including tests of forces 10 times stronger than gravity and blasts of sound to mimic rocket explosions.
• Then they will test for the conditions the JWST will face during two weeks of delicate unfurling in space and years in orbit.
• In February, the scientists will send it to a chamber at the Johnson Space Center that can be lowered to -220C (about -370F), which is designed to survive collisions with space debris and small holes in its mirrors, and that the telescope will need six months in space before it’s ready for work.
• The JWST was originally meant to launch in 2014, but the project was nearly canceled by Congress in 2011 due to delays and budget problems.
• This telescope will help scientists see stars and planets from the earliest epoch of the universe.

By: Vishal