Astronomy – High hopes for game changing telescope

On October 12, an unassuming ship arrived in French Guiana, carrying with it the $10 billion James Webb space telescope. 

The telescope is named after the former NASA chief James Webb who led the space agency from 1961 to 1968, before retiring just a few months before NASA put the first man on the moon.

The telescope will be driven to Europe’s Spaceport in the French Guiana town of Kourou, where it will be made ready for a planned December 18 launch on top of an Arianespace Ariane 5 rocket.

After liftoff, it will head towards its new home at Lagrange point 2, which is about 1.5 million kilometres away from us. This trip will take about 30 days. From this vantage point, the telescope will start observing the cosmos in infrared light.

If anything were to go wrong, humans would not be able to service James Webb, which is something engineers were able to do with the Hubble space telescope after they realised something was wrong with its mirror shortly after launch.

The ability to peer back 13 billion light years into the past is what sets this telescope apart from the better-known Hubble. With its primary mirror sitting at 6.5 metres across, it will be 100 times more sensitive than Hubble. James Webb will be able to see what the universe looked like up to a possible 100 million years after the Big Bang, when the first stars and galaxies started to form.

The James Webb space telescope has four key goals: to search for light from the first stars and galaxies that formed in the universe after the Big Bang; to study the formation and evolution of galaxies; to understand the formation of stars and planetary systems; to study planetary systems and the origins of life.

These goals can be met by observation in near infrared light, rather than light in the visible part of the spectrum. For this reason the James Webb’s instruments will not measure visible or ultraviolet light like the Hubble telescope, but will have a much greater capacity to perform infrared astronomy.

James Webb will also use a specialised device to block out light from some distant stars, enabling the observatory to snap pictures of any objects orbiting those stars, such as exoplanets (planets outside the solar system). 

Those planets will glow in the infrared, and the chemicals and elements in their atmospheres will alter that light – chemicals and elements that may be signs of life!

This telescope is going to revolutionise our understanding of our universe and where we came from. Its contributions to science will be extraordinary. If all goes to plan, these kinds of breakthroughs could come in a matter of months. Astronomers around the world are waiting for the countdown to begin!