Astronomy – James Webb sees first light

Last month, the $10 billion James Webb Space telescope was fully focused and its performance is even better than hoped. 

Once the mirrors had been deployed, they had to fine-tune each of the 18 segments, a fraction of the width of a human hair at a time. At the same time the telescope is cooling down, which also has an affect on the focusing.

To ensure that they do this properly, scientists had to focus on a target star. In this case, they used a star named 2MASS J17554042+6551277. This star is 100 times fainter than the faintest object we can see with our eyes from Earth.

Once each section was aligned, the telescope took its first test picture of the star and the results were mind-blowing.

Not only did the telescope capture the star, but also a host of ancient galaxies behind it – some of which we have never seen before.

Marshall Perrin, deputy telescope scientist at the Space Telescope Science Institute in Baltimore, says the images are focused together as finely as the laws of physics allow. “But as we were focusing on those bright stars, we couldn’t help but see the rest of the universe coming into focus behind them, to see the more distant stars and galaxies coming into view.”

This test image of a single star is only the beginning. Once the telescope begins taking scientific images, it should help unravel some of the universe’s biggest mysteries, from the potential habitability of exoplanets (planets soutside the Solar System) to dark energy.

The James Webb Space telescope will be able to peer inside the atmospheres of exoplanets and observe some of the first galaxies created after the universe began by observing them through infrared light, which is invisible to the human eye.

For the next couple of months, the team will finish the last steps of the alignment process and ensure all of the science instruments are calibrated.

The first high-resolution images of the cosmos collected by the telescope aren’t expected until the end of June.

Until then we have to wait and wonder at the mysteries that it may uncover.