John Mather, Nobel Prize winner for his groundbreaking observational work on the Big Bang, recently visited The University of New Mexico to share insights on the James Webb Space Telescope (JWST) and its early results.
The idea for a new telescope to replace the Hubble Telescope began in 1989 at a Next Generation Space Telescope Workshop at the Space Telescope Science Institute. Nearly 35 years later, the dream became reality when early results from the James Webb Space Telescope (JWST) started to be revealed and talked about with incredible images based on the telescope's ability to observe infrared light.
The James Webb Space Telescope is a much larger telescope than the Hubble Space Telescope. It picks up infrared light that the Hubble cannot see. Astronomers use the JWST to see things too cold to emit their visible light; they want to see farther out in space or further back in time.
Nobel Laureate John Mather explores JWST images, astronomy and astrology in latest podcast
By Carly Bowling
The latest episode of It's (Probably) Not Rocket Science explores images and early results from the James Webb Space Telescope (JWST) with John Mather, Nobel Laureate and the Webb telescope's senior project scientist emeritus, and Tony Hull, a UNM adjunct professor and the former JWST program manager at Tinsley.
The James Webb Space Telescope allows scientists to peer 13.5 billion years into the past and photograph the origins of the universe. In the short time it has been in space, its images have changed what we know about the birth of stars, how galaxies form and what makes up the atmospheres of the nearest planets.
Watch the episode on YouTube or listen to It's (Probably) Not Rocket Science on Spotify, Apple Podcasts, or anywhere else you get your podcasts.
Infrared light is the same as regular light, except the wavelengths are longer, meaning it doesn't need to be quite so hot to produce infrared light.
The JWST is engineered with specialty mirrors to capture infrared light. The telescope operates with an oversized concave mirror that focuses the light down to a small image, and the big mirror is made out of 18 smaller mirrors. The mirrors are shaped like hexagons made of beryllium, a difficult material to work with. The mirrors are coated with gold and look beautiful.
"Of course, we didn't do that for beauty. We did that because it's the best reflector for infrared light," Mather said.
Tony Hall, adjunct professor of Astronomer/Space missions at UNM and a good friend of John Mather, was responsible for making the mirrors have the right shape for the JWTS.
Each mirror is about four and a half five feet across the hexagon. The mirror is 21 feet across, bigger than the rocket. The other significant component is the sunshade, a big umbrella of five layers bigger than a single tennis court. This presents an exciting challenge since all of these parts have to be folded up to get inside the rocker, which is much smaller.
The JWST can show inside dust clouds where stars are being born today with their little planets.
The JWST orbits Earth and the sun simultaneously. It's a million miles overhead at midnight, and it orbits around a spot called Lagrange Point Two, which is a place where the combined gravity of the sun and earth is just enough to pull the telescope around the sun once a year, even though it's a little farther from the sun than the earth is.
When the telescope is in orbit, it constantly takes those pictures in the infrared. "We take pictures all the time with it as fast as we can," Mather said. Knowing where to point the telescope is a huge question. Mather said that they ask their community of astronomers worldwide, "Where do you want to point?" they answer with a proposal, helping Mather and his team decide where to point the telescope.
One of the most significant discoveries made by the telescope is the first galaxies. "A galaxy is 100 billion stars orbiting around the common center pulled together by gravity," Mather said. "We do not know how that came to be exactly. At the beginning of time, it almost did not have galaxies in it. It had what we call the 'Big Bang," which was an extremely hot and dense condition of the very early universe."
"This is our story. This is how we human beings come to have a place to live on a little planet around an ordinary star in an ordinary galaxy." – John Mather, Nobel Laureate and JWST senior project scientist emeritus
The JWST telescope was designed and built specifically to find out what the first galaxies were like.
"They're not quite like what we thought they were, and surprisingly big, bright, powerful, and numerous compared with what we expected. They're not round, which maybe we should have expected, but we weren't thinking about it that way," Mather said.
From his role as JWST Senior Project Scientist Emeritus, Mather said he's been very fortunate to be involved with some fantastic discovery processes with exceptional teams of scientists and engineers. He first measured the 'Big Bang' and then was curious about answering the question, "What happened next?"
By asking these questions, the Webb telescope was built to answer, "How did the first objects form from the primordial material?" The Webb telescope took 20,000 people, and having a significant team behind this project played a vital role.
"None of us did this alone. It took the support of our governments in the United States, Canada, and Europe to do this. And extremely powerful project management. You can't accomplish something this big and complicated without real skill and real process," said Mather.
The JWST will be a 20-year continued operation, examining the following questions: "What are the first objects that grew, and what are they like now? Are stars being born today nearby? How are planets made? What are they like?"
Through this telescope, "we're looking at the chemistry of our solar system that tells us something about the history of the earth," Mather said. He goes on to say that our solar system seems unique among all the systems he's ever seen because our solar system has four little rocky planets (Mercury, Venus, Earth, and Mars) in the middle. Then our system has a gap where the asteroids are, and then four giant planets, gaseous planets that are big and cold.
"We're curious to know, is this necessary as a condition for life? Some people say it is, some people say it isn't. So, we got to go look," he said. "This is our story. This is how we human beings come to have a place to live on a little planet around an ordinary star in an ordinary galaxy. So, we can tell you the story of the atoms and how that happened. Then I like to think about what does that mean? Here we are not so very big, but in my small but mighty here on earth, this is a way that the universe has to become conscious."
Reflecting on this whole process, Mather emphasizes an important message.
"It tells us a little bit like, take care of your home and look after the planet as much as you can. Then we also have another message, which is we can do good stuff. We can do really difficult international projects and have them come out right in the end," Mather said. "As President Kennedy said when he announced that we were going to the moon back in 1962, we were going to do this not because it's easy, but because it is hard and we're going to do this and the other things, too."
Mather recently gave two public talks at the University of New Mexico on Jan. 25 to communicate with the non-astronomers about the stories, answering these questions: how did we learn about the history of the universe? What does it mean? How far can we go? Are we alone?
His second talk was more oriented towards the technical content of "How do you build a telescope and how do you make it work? A little more details about the instrumentation on the telescope."
"I'm here partly because friends here in Albuquerque and Santa Fe invited me to come. They invited me because we have this story of the Webb telescope, but also the story of the universe," Mather said.
Mather explains that he admires a new image from the JWTS every day. One of his favorite images, however, is the picture that President Joe Biden announced on July 11, 2022. It shows a few stars with their bright spikes sticking out of the images, a few big fuzzy objects in the middle, which are enormously massive galaxies pretty nearby, and it shows a lot of little pink distorted arcs around the picture, which are magnified images of much more distant galaxies.
"It demonstrates the power of the telescope and our ability to use the natural lenses to extend our view as far back in time as we could possibly imagine going," Mather said.
