James Webb Space Telescope completes 1.5 million kilometer journey from Earth to study evolution of galaxies

Artist+concept+of+the+James+Webb+Space+Telescope+in+space.+After+reaching+L2%2C+the+JWST+will+study+the+formation+and+evolution+of+the+universes+earliest+galaxies.

Provided by nasa.gov

Artist concept of the James Webb Space Telescope in space. After reaching L2, the JWST will study the formation and evolution of the universe’s earliest galaxies.

by Edward Huang, Reporter

The James Webb Space Telescope (JWST) completed its 30-day journey into space on Jan. 24 and now floats 1.5 million kilometers away from Earth. From there, it will explore distant galaxies and their pasts to learn about their origins.

The National Aeronautics and Space Administration’s (NASA) latest telescope launched from the Guiana Space Centre in Kourou, French Guiana, on Dec. 25, 2021. Equipped with infrared cameras and its signature set of 18 gold mirrors, the James Webb Space Telescope is the largest of its kind that NASA has ever sent into space.

“Webb was designed in order to be the successor of NASA’s last telescope, Hubble,” upper school physics teacher Dr. Mark Brada said. “The Hubble space telescope has a [2.4] meter diameter mirror, and Webb is almost [three] times as big as Hubble, so almost [nine] times the light gathering power.”

The JWST also traveled much farther than Hubble, ending its journey at the Second Lagrangian Point, or L2, located 1.5 million kilometers behind the Earth as viewed from the Sun. At this point, the JWST can better regulate its temperature and remain stable while observing the universe.

“L2 is where the gravitational effects of the Earth and the Sun cancel out,” said Arnav Swaroop (10), Astronomy Club officer and Physical Sciences Club co-president. “It requires very little energy to keep the telescope going once it gets into orbit. Also, because the James Webb Telescope is in the shadow of the Earth, it can keep itself cool without making any adjustments.”

According to Arnav, the James Webb Space Telescope needs to maintain a low temperature because it was designed to detect faint heat signatures from distant galaxies with minimal interference from nearby objects like the sun. As a result, its mirrors are protected by a sunshield that deflects any heat coming from the sun.

“This telescope is incredibly special because it’s an infrared telescope, and its main focus is to detect small, dim galaxies and exoplanets and their atmospheres from far away,” Arnav said. “Heat is one of the biggest factors in [detecting] infrared. This is why you need to get as far away from the sun as possible while still being able to transmit data back to Earth.”

“This telescope is incredibly special because it’s an infrared telescope, and its main focus is to detect small, dim galaxies and exoplanets and their atmospheres from far away. Heat is one of the biggest factors in [detecting] infrared. This is why you need to get as far away from the sun as possible while still being able to transmit data back to Earth.””

— Arnav Swaroop (10)

According to NASA, the JWST will use the infrared data it collects to study the formation of the earliest objects in the universe created by the Big Bang. By looking into deep space and observing far away galaxies, the telescope can essentially look back in time to view the evolution of galaxies from the earliest stages of the universe.

“When Webb is looking at galaxies that are very far away, because light takes billions of years to travel from these galaxies to the telescope, it is also looking at things that are very far in the distant past,” Dr. Brada said. “Webb is principally designed to look at infrared light because all the stuff that’s really far away is primarily giving off light in the infrared part of the spectrum.”

The JWST has three gold plated mirrors, the largest of which spans 6.5 meters in diameter. The large size of the mirrors will allow the JWST to view a wide range of galaxies in their evolutionary processes, helping scientists better understand how an individual galaxy grows and develops. 

“Galaxies evolve over billions of years, so we can’t just watch a single galaxy from birth to death,” Dr. Brada said. “But we can look at a bunch of really old galaxies and middle aged galaxies and really young galaxies, and that can help us get the overall picture of how a galaxy evolves.”

With these findings, the JWST will hopefully give humanity a glimpse of the formation of the earliest galaxies, according to upper school physics teacher Dr. Miriam Allersma.

“One part of being human is trying to understand where we came from,” Dr. Allersma said. “And so why not go for it? Why not try to figure out where we came from, and where it all started, and how it all came to be?”