In a far-ranging talk Wednesday on space, physics and the origin of all that is, Nobel Prize-winning scientist John Mather went from the very old and incredible small, to the infinite, and nearly back again.
“I wanted to describe the entire history of the universe beginning with the Big Bang,” he said. “The entire universe expanding into itself, with gravity pulling things together to make stars and galaxies out of the primordial stuff, eventually leading to the people around us, trying to ask the question of, ‘How did we get here?’ ”
That, and how to keep the nuts and bolts on NASA’s James Webb Space Telescope from shaking apart during launch, as Mather explained to the crowd of at least 50 people at Bear Branch Nature Center.
Mather is a senior astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt and senior scientist on the James Webb Space Telescope project, which aims to put a telescope more powerful than the Hubble Space Telescope into space by 2021.
The talk was part of the monthly meeting of the Westminster Astronomical Society — which regularly has speakers including experts from NASA, as well as star parties and planetarium shows at the nature center — but Wednesday marked the first visit from a Nobel laureate, according to club founder Curt Roelle.
Last month NASA launched the Parker Solar Probe, its second deep space mission in 2018. (The other was Insight, destined for a November landing on Mars.) Parker is different from other solar missions of the past that observed the sun from far off. Parker will get up close and personal.
In 2006, Mather, along with George Smoot, was awarded the Nobel Prize in physics in 2006 for work on the Cosmic Background Explorer Satellite, which provided the first accurate measurements of the cosmic microwave background, the afterglow of the Big Bang.
“To me, the archetype of a great scientist was someone who could build some equipment that could measure something that had never been done,” Mather said. “I’ve been pushing that idea ever since I was little, when with cardboard tubes and my lenses made a little telescope.”
Today, as Mather explained to the crowd, he is working on the same fundamental equipment, only much larger and many times more precise: The James Webb Telescope, in development since 1995, will train a nearly 22-foot-wide primary mirror composed of 18 adjustable, hexagonal mirrors made of beryllium at the sky, and peer far enough away in the infrared portion of the spectrum to see, scientists hope, the very first galaxies. To see 13.8 billion or more light-years away is also to see billions of years into the universe’s past, according to Mather.
That was mind-blowing to Beth LeFevre, of Jefferson, Pennsylvania, a member of the club who had been looking forward to Mather’s talk for months.
“I like to think about the beginnings of the universe, where it started and where it’s going from there,” she said. “He kept saying they are also looking back in time, back into the history of the universe, and I like that idea. I don’t really understand it because I am not a physicist and I don’t understand the math that goes into it, but I like the thought that it’s not just static; it’s still an evolving thing and expanding.”
Creating a tool that can actually do that is, however, much easier dreamed than launched, Mather said, which is why it has taken years to develop and why he plays the role of mediating between NASA’s scientist and engineers.
“Scientist and engineers have a little bit different perspective about things. I’m on the side of, it would be great if we could build it this way,” he said. “Scientists say, we could measure. Engineers say, we could build. Scientists say, we need to measure better. Engineers say, we can’t build that. So I am in the middle and try to make this come to an agreement. After we say, OK, this is what we need to do to make it happen.”
Testing of the Jame Webb Space Telescope is nearing completion leading up to the planned 2021 launch, but rather than charting a course for retirement, Mather is already dreaming up his next big project: A tool to allow earthbound telescopes to go hunting for planets around other stars: a star shade.
“This is a really hard problem because planets are faint and stars are bright. You need a really big telescope to be able to see them at all and then you need to be able to block the bright light of the star,” Mather said. “So my new idea is not so completely new, but it says, let’s put a star shade, something very large, and put it in space. Let it cast a shadow of the star on a telescope on the ground.”
Coming up with what seems to him to be a good idea, and then seeing if other people will agree — and maybe put together a team to build the idea — is what excites Mather and keeps him going.
And while a senior NASA astrophysicist has some privileged access to the cutting-edge instruments of science, Mather notes that there has never been a better time for amateurs to get involved in learning about science, and even participating in citizens science programs. Today’s tools have opened new horizons in the heavens and on Earth.
“Nowadays we have tools we never had. Everybody has a computer in their pocket and whatever you want to know, you can look it up in a flash,” Mather said. “We can look at the sky and investigate our own history because we can now.”