The best kind of Christmas present is one that keeps on giving, and the James Webb Space Telescope (JWST) has done exactly that since its launch four years ago. On December 25, 2021, the $10 billion spacecraft took off from French Guiana, marking a new era in astronomical exploration. NASA planetary scientist Stefanie Milam recalls the tense moments leading up to the launch, describing the atmosphere at the Goddard Space Flight Center in Maryland as one filled with anticipation and pressure.
The JWST, a collaboration between NASA, the European Space Agency, and the Canadian Space Agency, was designed to show the cosmos as it had never been seen before. However, its journey to the stars was fraught with delays and challenges, including complications from the COVID-19 pandemic. Despite these hurdles, the telescope launched successfully, marking the beginning of what was dubbed the “30 days of terror” as it unfolded its sun shield and traveled to its destination.
Revealing the Cosmos
In March 2022, the JWST team released a test image of a star 2,000 light-years away, surrounded by ancient galaxies billions of light-years away. This was just a taste of the telescope’s capabilities. By July 12, 2022, then-US President Joe Biden unveiled the first official image from the JWST, showcasing galaxies from close to the dawn of time. Australian astronomer Robin Cook likened this moment to “Christmas in July” for astronomers worldwide.
Stefanie Milam, the JWST’s project manager for policy and science community, was part of the team selecting these images. Among the breathtaking visuals was a giant bubble of gas surrounding a small star, known as a planetary nebula, and the Carina Nebula, which left Milam overwhelmed with emotion.
Science Behind the Beauty
Beyond the beautiful images, the JWST has been achieving significant scientific milestones. It has provided unprecedented views of planetary auroras and rings around our outer planets, as well as insights into the atmospheres of exoplanets. The telescope’s capabilities have exceeded expectations, despite occasional impacts from micro-meteorites.
Milam notes the discovery of “super puffs,” planets with massive atmospheres that challenge existing theories. These findings have opened new avenues for research, including the study of atmospheres on alien planets in search of Earth-like conditions.
Unexpected Discoveries
The JWST’s revelations about the early universe are particularly exciting for cosmologists like Karl Glazebrook of Swinburne University. The telescope has detected galaxies that formed between 200 million and 260 million years after the Big Bang, some of which are unexpectedly luminous or massive. These discoveries suggest that the universe was evolving rapidly much earlier than previously thought.
Among the intriguing findings are mysterious red dots that aren’t galaxies but appear red due to light bending around galaxies. Glazebrook believes these could point to new science about black holes or dark matter, offering a tantalizing glimpse into the universe’s mysteries.
Looking Ahead
The JWST is expected to operate for at least 20 more years, continuing to expand our understanding of the universe. Milam is optimistic about the future, highlighting the potential for new generations of scientists to build on the telescope’s legacy. “It’s fantastic to think of the next generation coming in and owning that science and new research with a telescope that you once got to play a role in,” she says.
As the JWST continues its mission, it promises to keep dazzling us with its discoveries, ensuring that it remains a gift that keeps on giving to the scientific community and the world.
