Mankind is about to put a pair of eyes 1.5 million km above the earth, to peer into the earliest galaxies.
On October 31 this year, an Ariane V rocket will blast off from its launchpad in French Guiana, carrying that very interesting passenger: The James Webb space telescope. We all know of the Hubble telescope, which was placed 547 km above earth in 1990. The Webb, with a sun-shield as big as a tennis court, is six times bigger than the Hubble.
From its perch at the second sun-earth Lagrange point, or L2, the Webb will pick up infra-red signatures from the earliest galaxies, basically looking at the very first rays of light after the Big Bang. (A Lagrange point is where two celestial bodies, such as the sun and earth, exert the same gravitational pull, letting an object remain fixed there. India’s Aditya-L1 spacecraft, to be launched in January 2022, will be positioned at L1, between the sun and the earth.)
The Webb telescope will also look at the physical and chemical properties of planetary systems, look into the atmospheres of exoplanets (planets of other stars) for traces of life. And it will look a lot into our own solar system.
Webb is to scientists what a bottle of chilled beer is to a desert traveller — it has been booked solid. Over a thousand scientists from 17 countries worked on it and they have been given the first 4,000 hours, after the first 500 hours of opening and testing. Beyond that, scientists around the world have already booked 6,000 hours — going well beyond the 8,760 hours that make a year.