In a study published on November 6 Planetary Science Journal, It explores how NASA’s James Webb Space Telescope (JWST) first detected carbon dioxide in a centaur named 39P/Oterma. A Centauri is a small planetary body that orbits between Jupiter and Neptune and often crosses the orbits of one or more of the giant planets in our solar system.

Although no centaurs have ever been depicted up close, they often exhibit a combination of comet and asteroid features. Although carbon monoxide has been found in only two known centaurs, this latest discovery could be a turning point in how scientists understand the formation, evolution and composition of not only centaurs, but also the early solar system.

The lead author of the study, postdoctoral researcher Dr. “The study of Centauri is important because they are extremely well-preserved objects in space and can provide insight into the chemical composition and physical processes of the early solar system,” said Olga Harrington Pinto. Auburn University, but did research as a Ph.D. The University of Central Florida student tells Universe Today.

Centaur 39P/Oterma was launched on April 8, 1943 by Finnish astronomer Dr. It was discovered by Liisi Oterma. She was the first woman in Finland to earn a doctorate in astronomy. University of Turku, Faculty of Science. Although 39P/Oterma has long been classified as an inactive comet, it currently has a centaur orbit between Jupiter and Saturn, meaning it does not approach the Sun and is about 2.21 to 2.49 km (1.37 to 1 It has a radius of .55 miles. ), according to this study. So why was 39P/Oterma chosen for this particular study?

Professor of physics and astronomy at Appalachian State University, Dr. “39P/Oterma is what we call an active centaur, a centaur that develops a coma and tail like a normal comet,” said Adam McKay. the study’s co-author tells Universe Today. “Because they are active, we can use spectroscopy to observe molecules in the coma and gain insight into their composition. 39P was chosen as one of our targets because it would be active during the proposed observations.”

For the study, researchers used JWST’s Near Infrared Spectrograph (NIRSpec) instrument and examined the properties of 39P/Oterma as it orbited near perihelion (closest distance), supported by ground-based observations from the Gemini Northern Observatory and the Lowell Reconnaissance Telescope. It is 5.82 AU from the Sun in July 2022. For context, the perihelion of 39P/Oterma has been increasing since its discovery: 3.39 AU. (1958), 5.47 AU (1983) and 5.71 AU (2023), which are expected to reach 5.91 AU and 6.15 AU in 2042 and 2246, respectively.

Analyzing JWST NIRSpec data, researchers confirmed the first detection of carbon dioxide in any centaur and the smallest amount of carbon dioxide ever detected in any centaur or comet. They also found no traces of water or carbon monoxide traditionally found in centaurs, including 29P/Schwassmann-Wachmann 1 (29P/SW1), another centaur with nearly the same AU distance as 39P/Oterma.

Dr. “These results are important because they show that thanks to JWST’s impressive capabilities, we can see the underperformance of a relatively small object very far away,” Pinto told Universe Today. “Although its production rate is low, it shows a different chemical behavior from 29P/SW1, another centaur observed at the same distance (~6 AU). This difference in chemical behavior may be due to the very different sizes of 29P centaurs and 39P either in different orbits.” “They have backgrounds, or they start from different combinations, or maybe a combination of all of these.”

The discovery of carbon dioxide in a centaur could be a game changer for understanding the composition and properties of centaurs, asteroids, and comets in the Solar System, potentially leading to a better understanding of the formation and evolution of the Solar System. general. Source