October 8, 2021

ASU astronomers discuss NASA's new James Webb Space Telescope, which launches in December

In a little more than two months, humankind’s most powerful eye on the universe will launch, literally giving astronomers the ability to look back in time.

The James Webb Space Telescope is an orbiting infrared observatory with longer wavelength coverage and greatly improved sensitivity. The longer wavelengths enable Webb to look much closer to the beginning of time and to hunt for the unobserved formation of the first galaxies, as well as to look inside dust clouds where stars and planetary systems are forming today.

Thursday night a panel of Arizona State University scientists and students reviewed the telescope, which will launch from French Guiana on Dec. 18.

The panel was the first in a lineup of events ASU has been selected to host in honor of the telescope's launch.

“Our universe is filled with galaxies,” said senior Liam Nolan, an undergraduate student who researches under the direction of Regents Professor Rogier Windhorst in the School of Earth and Space Exploration.

Nolan displayed the famous Hubble Ultra Deep Field photo, a shot of 10,000 galaxies that look like Lucky Charms against a star field. Thirty-one years after Hubble’s launch, the telescope is now about 12 years past its design life. The primary Webb mirror is 2.5 times bigger than Hubble's and will see longer wavelengths.

“With James Webb we’ll be able to look at those in much more detail,” Nolan said.

Windhorst, an astronomer and Foundation Professor of astrophysics, is one of the world's six interdisciplinary scientists for the telescope. His group at ASU plans to use the Webb telescope to map the epoch of the first light in the universe in detail.

“We’ll see these very early galaxies and stars,” he said.

ASU research scientist Rolf Jansen provided input and support for NASA to the James Webb Space Telescope project. Jansen studies nearby galaxies.

“It might provide for early detection of interstellar visitors, like Oumuamua,” Jansen said, referring to the mysterious interstellar object that passed through our solar system in 2017.

Rosalia O’Brien is a graduate student in Jansen’s lab, studying light in the universe.

Galaxies get redder the farther away from Earth they are, she said. Hence, the farther away a galaxy, the faster it is receding from Earth. The galaxies are moving away from Earth because the fabric of space itself is expanding. It takes time for the light to reach us.

With filters on the Webb telescope, “we’ll get a better idea of how these red galaxies look,” O’Brien said.

Since Webb can see farther back in time, it will be able to see galaxies Hubble can’t.

“James Webb is going to look at red galaxies far back in the universe,” O’Brien said. “But the most exciting thing for me is we’ll be able to see the first galaxies.”

The discussion was part of the New Discoveries Lecture Series, which brings exciting scientific work from the school's researchers to the general public in a series of informative and up-to-date evening lectures. Each lecture is given by a member of the School of Earth and Space Exploration's faculty.

Top image: Artist conception of the James Webb Space Telescope. Credit: NASA GSFC/CIL/Adriana Manrique Gutierrez 

Scott Seckel

Reporter , ASU News

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