The James Webb Space Telescope and What It Means for Humanity
In the year 1609, Galileo pointed one of the first telescopes ever created up at the heavens, and what he observed sparked a revolution of curiosity that has been central to every single human generation since. Galileo saw mountains and craters on the surface of the Moon, the arm of our Milky Way galaxy arching across the sky, and an endless universe riddled with countless stars. The mysteries of outer space were boundless, and the journey towards discovering them had only just begun. Over 400 years later, our obsession with the enigma that is space has only managed to intensify, fueling many great technological advancements that have made our ever-expanding universe seem smaller and boundaries closer than ever.
On the 25th of December 2021, NASA launched humanity's most powerful telescope yet. More than 30 years in the making, $10 billion spent, a successful launch, 50 intricate outer space deployments, and a distance of over 1.5 million kilometers traveled from Earth, the James Webb Space Telescope has finally delivered its first full-size images of our universe. This marks an area of space discovery that promises unique and unprecedented views, from across our own solar system to the very heart of the universe. The James Webb Space Telescope (JWST for short) has been designed to look more than 13.5 billion years into the past, to study the farthest and oldest regions of space, peering back into the early days of the universe.
Its aim is to look at the first galaxies that started forming and emitting light right after the Big Bang. It's no wonder that scientists often refer to telescopes as time machines. In them lies the power to see what our universe once was and perhaps answer one of humanity's most perplexing existential questions: How did we get here? Right now, Webb is our best chance at finding an answer to that question. However, to fully understand what makes Webb so special, we have to travel back in time to the year 1990, when the Hubble Space Telescope was launched.
The Hubble Space Telescope embarked on a mission similar to Webb's. Its purpose, just like Webb's, was to study the universe like it's never been studied before and to bring us closer to understanding our existence and our place among the stars. Over the past 30 years, Hubble has brought us images of galaxies we never knew existed, star clusters, and nebulae like we've never seen before. These images helped illustrate how, in the early days of our universe, just millions of years after the Big Bang, cold clouds of gas and dust evolved into swirling, coalescing galaxies teeming with stars.
Sadly, that was just how far Hubble could see. In order to observe how these first galaxies were born, we needed a bigger telescope—one that wasn't just more powerful but that could also operate in the infrared. So, just a few years after Hubble was launched into space, scientists began working on the next big telescope. Today, Webb is 100 times more powerful than Hubble, and its ability to observe infrared light opens up a new universe of possibilities, literally.
Ever since Edwin Hubble discovered that the universe is expanding, we've known that galaxies have been receding at faster and faster speeds. Light from these galaxies is stretched to longer wavelengths as it travels through space, which is why they're only visible through infrared. Hubble, the telescope, is only able to see light on the visible spectrum, which means it's limited in the amount of information that can fetch us about these earliest galaxies. But with Webb, we finally have the ability to observe them. To detect these infrared waves, Webb traveled more than 1.5 million kilometers away from Earth's warm atmosphere to a very cold region in space that is protected from our planet's infrared radiation.
Built into this telescope are huge sun shields as big as a tennis court that protect it from the rays of the sun and help keep its temperature at minus 233 degrees Celsius, so it can be cool enough to detect infrared radiation from the early days of the universe. This is the first time in the history of our species that we've been able to look at our universe with such incredible detail.