Leading Astrophysicist Talks Obstacles, Expectations for Next Big Step in Space Observation
Dr. John C. Mather is part of the Nobel Laureate School Visits program, a partner organization of the 2014 USA Science & Engineering Festival in Washington, D.C., which took place April 26–27, 2014. Epoch Times was a media sponsor of the festival. See Epoch Times articles on the USA Science & Engineering Festival.
Left: An artist’s illustration of the James Webb Space Telescope (JWST). (NASA) Right: John Mather, senior project scientist on the JWST. (Chris Gunn/NASA)
In 1990, the Hubble telescope opened outer-space to the human eye in a revolutionary way. The time and money needed to develop a device of that magnitude makes such a shift in perspective possible only once in a few decades. In 2018, the James Webb telescope will bring the next great shift, and senior project scientist John Mather is grateful to be a part of it.
“I feel lucky to have a chance to do two major, wonderful projects, because each one of them can take 15, 20, or 30 years,” Mather said. An astrophysicist only has the chance about twice in a lifetime to work on projects this momentous—and those who get the chance to play a leading role, as Mather has, are especially few.
In the 1980s, Mather led the Cosmic Background Explorer Mission. He and his team measured the radiation said to have come from the Big Bang, finding significant evidence to support the Big Bang theory. His findings earned a standing ovation when he announced them to his peers, and earned him a Nobel Prize in physics in 2006.
Now, at the age of 67, he looks forward to another career milestone, also a milestone in space exploration.
What the Webb Can Do
The Webb telescope may be able to see the first galaxies that formed in the universe. It will be launched deeper into space than the Hubble and it will use infrared, allowing it to pick up on much that is invisible to the Hubble. By penetrating dust clouds, it may reveal wondrous sights—the genesis of planetary systems, perhaps, or the birth of a star.
It may be able to spot oceans on other planets, or help us learn enough about the formation of planets that we may better understand how life came to be on Earth.
The infrared Spitzer Space Telescope has given us a glimpse of what infrared imaging can reveal. The Spitzer is, however, a tiny telescope (only about 3 feet wide) compared to the Webb telescope (about 21 feet wide), and much greater findings are expected from the Webb.
Mather couldn’t say what the first priorities will be for observation. It hasn’t been decided yet, but he’s sure it will be “beautiful things and important things.” For the next decade, scientists will be able to write proposals for what should be observed by the Webb, as they do for Hubble.
Almost anywhere the telescope is focused, it is likely to reveal new details of structures and phenomena we have already observed, and it could reveal those we have never seen before.
Mather described some of the wondrous visions he can imagine the telescope may capture.
“I can speculate about the surprises I might like to see,” Mather said. “How about that we discover a new kind of galaxy out there that only existed in the early times and we don’t see any of them now because they’re all gone. How about we discover how black holes are made. It’s still quite a mystery how we have a black hole at the middle of every galaxy.”
How Does It Work?
The Webb will be launched into orbit 930,000 miles (1.5 million kilometers) from Earth. In space it will have an advantage over Earth-bound telescopes in that it will be able to pick up on light blocked by Earth’s atmosphere.
Its mirror segments are made of beryllium, a substance that can keep its shape at very cold temperatures. The mirrors are coated with a thin layer of gold, because gold is good at reflecting infrared light. Cameras and spectographs will receive the reflected light, providing researchers with images of space.
The gold also “makes it beautiful to look at,” Mather said.
An insulating shield as big as a tennis court will protect the telescope from the sun. On the side of the insulation facing the sun, solar panels will make electricity and radio antennae will communicate with Earth, allowing scientists to control the Webb after its launch.
All the major parts are ready, Mather said, and now it’s a matter of putting it together and testing. The largest thermal vacuum center in the world is being prepared to test the Webb telescope this summer.
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“[The instrument parts] all worked when they were sent to us, and we expect they will all still work, but this is their first chance to all play together,” Mather said. “The great hazard for us is that things that work when you build them don’t always work when you fly them.”
Learning From Past Mistakes
The Webb team learned much from the mistakes of the Hubble team. The Hubble wasn’t in focus when it was launched, for example, said Mather. The same equipment that built the Hubble was also used to test it, giving skewed results.
Mather said it is important to have the designs for all elements completed before starting to build and to bring new inventions to maturity before incorporating them in the design.
A lesson the Webb project will leave to the future is the importance of giving major projects the time and money to be done right. Funding faltered part way through the project, but Congress came through in the end, asking the Webb team what was truly needed to do its work well.
“NASA sent back a budget and schedule that was much bigger than before, and a miracle occurred: Congress said ‘yes,’” Mather said. “The progress has been very rapid and we’ve been able to stay on track with our budget and our schedule. … That’s a remarkable result of doing the right thing.”
One Good Invention Inspires Several Others
Developing the Webb telescope and other space telescopes has also helped us see better on Earth.
“Once in a while the applications are very far from where you think they might be,” Mather said. “Our ability to focus a telescope in outer-space uses the same mathematics that is now used to focus your eyesight.”
Optometrists have been able to greatly improve thousands of people’s eyesight using NASA’s space telescope research. Security organizations also benefit from space observatories. Looking down from space helps with military reconnaissance. Semiconductor and microprocessor designers are also always in search of better optical devices.
With decades between the Hubble and the Webb, the advances in technology are great. Scientists are already dreaming about what the next big telescope design could include. Mather said, “We’re pretty much at a point now where if you can imagine it, you can build it.”