James Webb Space Telescope 'can see backwards in time': all you need to know

The James Webb Space Telescope is the world's biggest and most powerful space telescope which rocketed away in December 2021 from French Guiana in South America.

It reached its lookout point of 1.6 million kilometers from Earth in January. Then the lengthy process began to align the mirrors, get the infrared detectors cold enough to operate and calibrate the science instruments, all protected by a sunshade the size of a tennis court that keeps the telescope cool.

The plan is to use the telescope to peer back so far that scientists will get a glimpse of the early days of the universe about 13.7 billion years ago and zoom in on closer cosmic objects, even our own solar system, with sharper focus.

Webb is considered the successor to the highly successful, but aging Hubble Space Telescope. Hubble has stared as far back as 13.4 billion years. It found the light wave signature of an extremely bright galaxy in 2016. Astronomers measure how far back they look in light-years with one light-year being 9.3 trillion kilometers..

Jonathan Gardner, Webb's deputy project scientist says
Webb can see backwards in time to just after the Big Bang by looking for galaxies that are so far away that the light has taken many billions of years to get from those galaxies to NASA's telescopes.