OSIRIS-APEX: An OSIRIS-REx Extended Mission to Asteroid Apophis

The Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft mission characterized and collected a sample from asteroid (101955) Bennu. After the OSIRIS-REx Sample Return Capsule released to Earth’s surface in 2023 September, the spacecraft diverted into a new orbit that encounters asteroid (99942) Apophis in 2029, enabling a second mission with the same unique capabilities: OSIRIS-Apophis Explorer (APEX). On 2029 April 13, the 340 m diameter Apophis will draw within ∼32,000 km of Earth’s surface, less than 1/10 the lunar distance. Apophis will be the largest object to approach Earth this closely in recorded history. This rare planetary encounter will alter Apophis’s orbit, will subject it to tidal forces that change its spin state, and may seismically disturb its surface. APEX will distantly observe Apophis during the Earth encounter and capture its evolution in real time, revealing the consequences of an asteroid undergoing tidal disturbance by a major planet. Beginning in 2029 July, the spacecraft’s instrument suite will begin providing high-resolution data of this “stony” asteroid—advancing knowledge of these objects and their connection to meteorites. Near the mission’s end, APEX will use its thrusters to excavate regolith, a technique demonstrated at Bennu. Observations before, during, and after excavation will provide insight into the subsurface and material properties of stony asteroids. Furthermore, Apophis’s material and structure have critical implications for planetary defense. © 2023. The Author(s). Published by the American Astronomical Society.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

The social psychology of "pseudoscience": A brief history.

The word 'pseudoscience' is a marker of changing worries about science and being a scientist. It played an important role in the philosophical debate on demarcating science from other activities, and was used in popular writings to distance science from cranky theories with scientific pretensions. These uses consolidated a comforting unity in science, a communal space from which pseudoscience is excluded, and the user's right to belong is asserted. The urgency of this process dwindled when attempts to find a formal demarcation petered out, and the growth of social constructionism denied science any special access to truth. The reaction to this led to the science wars, which ushered in a new anxiety in the use of 'pseudoscience', especially from the least secure branches. But recent writings on the disunity of science reveal how the sense of support drawn from it may be based on an illusion, creating a disunity of pseudoscience as well as of science