|The flight mirrors for the James Webb Space Telescope undergo cryogenic testing at NASA Marshall. Credit: Ball Aerospace|
In one of the most exciting developments in astronomy in the 21st century, NASA is launching the James Webb Space Telescope (JWST) today—and Northern Arizona University astronomers, planetary astronomers and their students will use the massive observatory to expand their research and advance our understanding of the solar system.
“Webb is NASA’s newest premier space science observatory—destined to be a household name, like its predecessor, Hubble,” NASA announced. “This is an Apollo moment for NASA science—Webb will fundamentally alter our understanding of the universe. It can observe all of the cosmos, from planets to stars to nebulae to galaxies and beyond—helping scientists uncover secrets of the distant universe as well as exoplanets closer to home. Webb can explore our own solar system’s residents with exquisite new detail and search for faint signals from the first galaxies ever made. From new forming stars to devouring black holes, Webb will reveal all this and more.”
The JWST, which NASA calls “a feat of human ingenuity,” is being launched in a global partnership with the European Space Agency and Canadian Space Agency. The mission has evolved over the past 20 years with contributions from thousands of scientists, engineers and other professionals from more than 14 countries and 29 U.S. states, including professor David Trilling, professor Josh Emery and assistant professor Cristina Thomas of NAU’s Department of Astronomy and Planetary Science.
“Only 22 research proposals were selected by NASA in the area of solar system science for the first cycle of projects,” Trilling said. “Collectively, our scientists are involved in seven of the projects, representing 65 percent of the time allocated in Cycle 1 of JWST for observations of the solar system.”
Along with their students, including Ph.D. student Audrey Martin, Trilling, Thomas and Emery will be conducting a variety of experiments once the telescope is successfully launched and commissioned.
Trilling, an astronomer, is principal investigator (PI, and Thomas, a planetary astronomer, is a co-PI on a project to measure the fraction of main belt asteroids that bear water. Along with other collaborators, the team will observe 100 asteroids with sizes as small as 100 meters. “We will measure the fraction of asteroids with hydration features larger than around 10 percent and derive the amount of water present in the asteroid belt,” Trilling said. “This experiment has implications for the formation and evolution of our solar system and life on Earth.”
Trilling is also co-PI on a search for the faintest trans-Neptunian objects (TNOs) ever detected, using the JWST to look for 30 objects as small as seven kilometers at distances up to 45 AU. (One AU is roughly the distance from Earth to the Sun and equal to about 150 million km, or about eight light minutes). “The result of this project will be a huge advance in our understanding of the dynamical and chemical evolution currently occurring in the distant solar system,” he said.
Thomas is a collaborator on an analysis of the low-albedo asteroid data being collected by the JWST on the Trojan asteroids Hektor and Patroclus; the main-belt asteroids Ceres, Pallas and Hygiea; and the near-Earth asteroid Phaethon. The data will be used to address questions such as “What is the range of hydrated mineral composition and amount of hydrated material present on the surfaces of low-albedo asteroids?” and “How can useful spectral information best be extracted from saturated JWST data?”
Thomas has been leading the Guaranteed Time Observations Program to observe near-Earth asteroids for several years; she is a collaborator on a related analysis of the low-albedo asteroid data being collected by the JWST on the Trojan asteroids Hektor and Patroclus; the main-belt asteroids Ceres, Pallas and Hygiea; and the near-Earth asteroid Phaethon. Also, as lead of the Observations Working Group for NASA’s DART (Double Asteroid Redirection Test) mission, which launched Nov. 23, Thomas and others in the group will use JWST to observe Didymos, including imaging in the months leading up to the DART impact and at the time of impact.
Thomas also is collaborating on a project that will investigate the physical and chemical properties of a target-of-opportunity interstellar object (ISO) to help elucidate the nature and origin of this fundamentally new class of astronomical body. “Our observations of interstellar objects will enable in-depth studies of the chemistry of other planetary systems,” Thomas said. “It is incredibly exciting to have the opportunity to examine these visitors from other systems and see how they differ from objects within our solar system. Since only two interstellar objects have been discovered, we don’t know exactly what we’ll see.”
Emery, a planetary astronomer, leads the Surface Composition Working Group for NASA’s Lucy mission, launched in October, which is designed to explore the Jupiter Trojan asteroids. The mission will utilize the capabilities of the JWST to probe the organic, carbonate and silicate components of the surfaces of the Trojans. Ph.D. student Martin co-leads the mission sub-team that will use the JWST to observe the Lucy targets. “Combined, the observations from Lucy and Webb will paint a rich picture of these asteroids, enabling us to trace connections with other bodies across the solar system,” Emery said.
Emery is a collaborator on a project that will use the JWST to observe 59 TNOs. “The TNO population includes some of the most primitive bodies in the solar system,” Emery said. “Our goal is to assess the relative ratio of water ice, complex organics, silicates and volatiles on the surface of a large sample of TNOs. This information is vital to improving models of the formation of our solar system and other planetary systems. It relates to disciplines such as astrochemistry, cosmochemistry and astrobiology, all of which are relevant to our understanding of the origin of water and life on Earth—and possibly elsewhere.”
Emery also is collaborating on a large team of scientists that will observe the Uranian moons Ariel, Umbriel, Titania and Oberon. “We will investigate the spectral evidence for past ocean world activity on these moons, assess the organic constituents on their surfaces and measure carbon and hydrogen isotopes to assess the formation conditions in the Uranian subnebula,” Emery said.
The JWST builds on the groundbreaking discoveries of other spacecraft, such as the Hubble Space Telescope and the recently retired Spitzer Space Telescope, focusing on infrared light, a wavelength important for peering through gas and dust to see distant objects. The telescope’s large mirror and advanced suite of instruments are protected by a five-layer sunshield, built to unfurl until it reaches the size of a tennis court. The entire observatory is folded up to fit inside the launch vehicle and is designed to unfold in space.
According to NASA’s communications, “This complex deployment sequence has never been attempted for a space telescope, and the amazing engineering that enabled Webb includes many innovations that push the boundaries of technology.”
Once launched, the observatory will undergo six months of commissioning in space, during which thousands of parts and sequences all have to work correctly together, almost a million miles from Earth. The commissioning period will be complete when the telescope begins to generate data—“a truly momentous celebration for the mission, NASA, the United States and the world.”
Source/Credit: Northern Arizona University