Spot on Science: The James Webb Space Telescope
There’s a new piece of technology currently floating a million miles away that NASA hopes will unlock the mysteries of the universe. In this week’s Spot on Science, Natalia Garcia tells us about the new telescope in town.
Class Discussion Question:
Research infrared light. What is the key difference between infrared light and ultraviolet light?
Read the Script:
Since our earliest civilizations, humans have been gazing up at the stars, trying to make sense of what they’re seeing. But, even though our technology for stargazing has improved over the years, much of what surrounds our planet in the universe is still a mystery.
The best images we have of space come from this guy: the Hubble Space Telescope. NASA launched it into space in 1990, and it is currently orbiting the Earth, about 340 miles away. Hubble was revolutionary in its time – rather than perching on a high mountain or tall building to get a closer view of the stars, as we’ve done with telescopes for hundreds of years, Hubble was launched directly into space – “the ultimate mountaintop,” as NASA calls it.
Hubble has given us views we’ve never seen before and solved mysteries, like “how old is the universe?”
But we just got a major upgrade – and it’s called the James Webb Space Telescope. The Webb telescope was launched on December 25, 2021, and flew past the Hubble, much farther into space. It has successfully reached its home: a position about 1 million miles from Earth that NASA calls L2. Rather than orbiting Earth, like Hubble, the Webb telescope actually orbits the Sun, in sync with Earth.
In addition to being farther into space than Hubble, the Webb telescope is also much larger. In fact, it’s about the size of a tennis court. And with that size comes more power – the large surface of golden mirrors on the front allow it to collect more light than the Hubble, and more light means Webb can see far-away objects more clearly.
The mirrors are gold – yes, real gold! – not because NASA is just trying to show off, but because gold is better able to reflect a different kind of light called infrared light. Infrared light is a type of light energy that's invisible to the human eye but that we can feel as heat. Using infrared light, the Webb telescope will be able to see through dust in our universe, and get a peek into other worlds.
But, it turns out, launching a tennis-court-size, gold-plated mirror into space without breaking it, is no easy task! In fact, the engineers at NASA had to create a telescope that would essentially assemble itself while floating in space. The telescope was securely folded into the Ariane 5 rocket for takeoff, but once in space, it started slowly unfolding.
As we speak, the Webb telescope is up in space aligning its mirrors to bring its first star into focus – and, because it’s got 18 mirrors to align, it will be doing this for the next 3 months. Because it is deeper into space, larger, and able to see infrared light, the James Webb telescope will be 100 times more powerful than the Hubble! With it, NASA expects to learn more about how the universe was created, and peer into the atmospheres of planets in other galaxies, in search of the building blocks of life.
You can expect to see the first set of images from the James Webb telescope this spring – but while we wait, I'll be taking a good look at the night sky to imagine what might be out there!