Insights into the Metallic Characteristics of Asteroid Psyche Revealed by SOFIA
In October 2023, NASA’s Psyche mission will embark on a journey to explore asteroid 16 Psyche, one of the largest asteroids in the asteroid belt. Psyche is believed to be rich in metals, but its true nature remains largely unknown. Recent research conducted by NASA’s retired Stratospheric Observatory for Infrared Astronomy (SOFIA) telescope and Ames Research Center has shed light on what scientists can expect to find when the spacecraft reaches Psyche.
Over the past few years, scientists have speculated about the characteristics of Psyche as they planned the mission. One prevailing theory suggests that Psyche was once the iron-rich interior of a planetesimal or a forming planet. The surface of the planetesimal is thought to have been eroded by constant collisions with other planetary material, leaving behind only the core, which is now known as Psyche.
Despite this hypothesis and supporting data, scientists still have limited knowledge about Psyche and its features. To gain more insights, a group of scientists led by Maggie McAdam and Anicia Arredondo used the SOFIA telescope to observe Psyche in February 2022. SOFIA was a unique telescope integrated into a Boeing 747SP airplane, allowing scientists to observe celestial objects from above Earth’s lower atmosphere and from any location on Earth.
The observations made by SOFIA were groundbreaking as they provided data from every part of Psyche’s surface. This enabled scientists to analyze the materials present on the asteroid’s surface, information that could not have been obtained using telescopes on Earth. The team used a mid-infrared camera on SOFIA to analyze different wavelengths of light reflected off the asteroid’s surface. They measured the emissivity, which is the amount of energy radiated into space, and the porosity, which refers to the number of small holes or openings on the surface.
The analysis of SOFIA’s observations revealed some interesting findings about Psyche. The emissivity and spectra data were flat, which is often associated with mid-infrared instruments used to observe metallic objects. This suggests that Psyche is likely a metallic body, aligning with scientists’ expectations. The absence of a spectral feature called the 10-micron plateau, which is typically found in objects with “fluffy” surfaces like lunar regolith, indicates that Psyche’s surface composition varies. Previous studies of the asteroid’s south pole showed the presence of the 10-micron plateau, implying that surface differences exist in different regions of Psyche.
Scientists are currently investigating the reasons behind these surface differences. One theory suggests that the material at the south pole might have been ejected from a collision that occurred elsewhere on the asteroid. Previous observations have shown that Psyche’s surface is marked by a high number of craters and depressions, supporting this theory.
However, scientists won’t have a clear understanding of the surface differences until the spacecraft reaches Psyche in 2029. Until then, they will rely on the data collected by SOFIA and other observational sources for analysis. The mission’s arrival will provide an opportunity for up-close imagery and observations that can answer the remaining questions about Psyche.
The unique characteristics and history of Psyche are precisely why scientists selected it as the 14th mission of NASA’s Discovery Program. If current predictions are correct, Psyche could provide answers to fundamental questions about planet formation. Furthermore, its resemblance to Earth’s metallic cores and its large size make it more likely to exhibit differentiation, a process in which materials separate within an object, with heavier materials sinking to the middle and forming cores. Understanding Psyche’s origins could yield valuable insights into the formation of rocky planets like Earth and Mars.
The upcoming launch of NASA’s Psyche mission on October 12, 2023, is highly anticipated. The mission will be launched atop a SpaceX Falcon Heavy rocket from the Kennedy Space Center in Florida. Both NASA and the National Science Foundation will broadcast the launch on various social media platforms, allowing the public to witness this exciting scientific endeavor.
In conclusion, the recent research conducted using the SOFIA telescope has provided valuable insights into the metallic characteristics of asteroid Psyche. Scientists have discovered that Psyche is likely a metallic body with a varied surface composition. These findings have fueled curiosity and anticipation for the upcoming Psyche mission, which aims to explore this enigmatic asteroid and unlock the secrets of planet formation.
