M. Al Asad

Impact-crater ejecta on Bennu indicate a surface with very low strength, submitted to Nature Geosciences

M. E. Perry, O. Barnouin, R. Terik Daly, E. B. Bierhaus et autres

A planetary surface’s resistance to change is generally described as its “strength” (units of stress). The surface strength of small, rubble-pile asteroids, which consist of fragments of larger bodies that were collisionally disrupted, is poorly con-strained due to their wide departure from …

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True and Apparent Polar Wander From Sluggish to Active Lid Tectonics

H. C. P. Lau, M. Al Asad

Abstract It has been proposed that to satisfy a wide range of geological observations, early Earth mantle convection operated in “sluggish‐lid” tectonics before transitioning to modern‐day, “active‐lid” tectonics. The former is the result of a weaker asthenosphere relative to the latter and …

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Coupled fates of Earth’s mantle and core: Early sluggish-lid tectonics and a long-lived geodynamo

M. Al Asad, H. C. P. Lau

Conventional Earth evolution models are unable to simultaneously reproduce two fundamental observations: the mantle's secular temperature record and a long-lived geodynamo before inner core nucleation. Today, plate tectonics efficiently cools the mantle, but if assumed to operate throughout Earth's history, past mantle …

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Efficacy of Oral Methotrexate in the treatment of Plaque Psoriasis in a local population

Attiya Tareen, Sohaib Asghar, Uzma Rajar, Dujanah S Bhatti et autres

Background: Plaque psoriasis constitutes around 90% of psoriasis prevalent in the world. It’s medically introduced as well demarcated erythematous plaques with coarse silvery scales predominantly involving extensor surfaces of the knees, elbows, sacrum, scalp, nails and sites of injury. Methotrexate has been …

Boulder Diversity in the Nightingale Region of Asteroid (101955) Bennu and Predictions for Physical Properties of the OSIRIS‐REx Sample

E. R. Jawin, Ronald‐L. Ballouz, A. J. Ryan, H. H. Kaplan et autres

Abstract The sample of asteroid (101955) Bennu was collected from the Nightingale sample site by the Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer spacecraft and arrived on Earth on 24 September 2023. To better understand Bennu's parent body, we identified boulders …

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Modes of Mantle Convection, Their Stability, and What Controls Their Existence

M. Al Asad, H. C. P. Lau, John Crowley, A. Lenardic

Abstract The motion of Earth's tectonic plates is the surface expression of mantle convection beneath. Analytical convection models have attempted to relate observables, such as plate velocities and surface heat flow, with the thermo‐mechanical state of the mantle, and remain deeply influential …

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High-resolution shape models of Phobos and Deimos from stereophotoclinometry

C. M. Ernst, R. T. Daly, R. W. Gaskell, O. S. Barnouin et autres

We created high-resolution shape models of Phobos and Deimos using stereophotoclinometry and united images from Viking Orbiter, Phobos 2, Mars Global Surveyor, Mars Express, and Mars Reconnaissance Orbiter into a single coregistered collection. The best-fit ellipsoid to the Phobos model has radii …

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Alignment of fractures on Bennu’s boulders indicative of rapid asteroid surface evolution

Marco Delbò, K. J. Walsh, C. Matonti, Justin Wilkerson et autres

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Low surface strength of the asteroid Bennu inferred from impact ejecta deposit

M. E. Perry, O. S. Barnouin, R. T. Daly, E. B. Bierhaus et autres

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Geologic Context of the OSIRIS-REx Sample Site from High-resolution Topography and Imaging

O. S. Barnouin, E. R. Jawin, R. T. Daly, Ronald‐Louis Ballouz et autres

Abstract The OSIRIS-REx spacecraft collected a surface sample from Hokioi crater (55.8° N, 42.3° E; diameter ∼20 m) on the asteroid Bennu in 2020 October. We explore the geology of the sample collection site, known as Nightingale, by using digital terrain models, …

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The Formation of Terraces on Asteroid (101955) Bennu

O. S. Barnouin, M. G. Daly, J. A. Seabrook, Y. Zhang et autres

Abstract The surface of the rubble‐pile asteroid (101955) Bennu has been characterized in detail by the OSIRIS‐REx (Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer) mission. By examining global and local digital terrain models, we observed that Bennu possesses terraces, that is, …

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Fractures on Bennu's boulders

Marco Delbò, K. J. Walsh, C. Matonti, Justin Wilkerson et autres

This is the data set corresponding to the publication entitled Alignment of fractures on Bennu’s boulders indicative of rapid asteroid surface evolution, by the same authors, which is to be published by Nature Geoscience.

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