Dr Nishant A.Irudayadason

Professor of Philosophy and Ethics, Jnana-DeepaVidyapeeth, Pune.

The James Webb Space Telescope, which is currently exploring the depths of the Universe in search of the first galaxies formed after the big bang 13.8 billion years ago, may have discovered the most distant galaxy ever seen by humanity. Named GLASS-z13, the galaxy was observed by James Webb’s NIRCam instrument, as it was only about 300 million years after the Big Bang. Launched into space about six months ago, the James Webb telescope located 1.5 million kilometres from Earth offers astronomers the opportunity to make great discoveries about the formation of galaxies, exoplanets, black holes or the first moments of the birth of the Universe. The product of a collaboration between the American, European and Canadian space agencies, the James Webb Space Telescope is equipped with high-performance instruments that make it the most powerful space telescope ever designed.

After several months of testing and calibrating the instruments of the James Webb telescope, the long-awaited shot was revealed to the world on Monday, July 11 at 11 p.m. by US President Joe Biden. The image is spectacular and shows galaxies formed shortly after the Big Bang, more than 13 billion years ago: This is the galaxy cluster SMACS 0723, as it was 4.6 billion years ago. The James Webb telescope will allow researchers to study structures that have never been seen before. NASA said it was the deepest and clearest infrared image ever taken of the Universe so far. This photograph marks the beginning of a long research work for astronomers, discovering the origins of the Universe and the formation of galaxies.

Launched on December 25, 2021, after 30 years of study and design, the James Webb Space Telescope reached its destination a month later, on January 24, 2022: the “Lagrange point L2”, a very stable area of the solar system. The precision of its take-off aboard an Ariane 5 rocket was such a success that NASA decided to extend the duration of the mission by 5 years while the telescope had just begun its transit to its final position. 6 months later, the deployment of the various instruments that make up the telescope went smoothly, allowing NASA to officially launch the space exploration mission of this jewel of technology that is the subject of great expectations from the scientific community. Alongside NASA, mission partner agencies – the European Space Agency (ESA) and the Canadian Space Agency (CSA) – participated in the design of various instruments on board the James Webb Telescope.

After launching aboard an Ariane 5 rocket, the James Webb telescope returned to its final location. It is now in orbit around Lagrange point 2. It therefore revolves around this location, but also around the Sun following the movement of the Earth. After taking off followed by a month-long journey, the James Webb telescope orbited a point in the solar system called the “L2 Lagrange point”. This point is located in the alignment of the Sun and Earth and allows the telescope to remain fixed in relation to these two objects. This point was chosen for its stability, thanks to which the telescope will not need to spend a lot of energy to keep its position. This location is also a way to keep the telescope’s instruments cool since it is located behind the Earth in relation to the Sun. However, this position is not enough to keep all its tools at a sufficiently low temperature. That’s why the telescope also has a huge sun visor to keep its instruments out of the heat.

The James Webb Telescope is expected to fulfil different objectives during its mission, which initially lasts 5 years, but could be extended to 10 years. First of all, James Webb will observe the first galaxies, which appeared just after the Big Bang. He will therefore go back in time to understand the formation of these structures and their diversity. The telescope will also study exoplanets and focus more specifically on their atmospheres, looking for bio-signatures, i.e., clues to potential traces of life within compounds in the planets’ atmospheres. Finally, it will keep an eye on an object much closer to us, the black hole Sagittarius A located at the centre of our galaxy, the Milky Way.