JWST sighting of decametre main-belt asteroids and view on meteorite sources.

Asteroid discoveries are essential for planetary-defence efforts aiming to prevent impacts with Earth, including the more frequent megaton explosions from decametre impactors. Although large asteroids (≥100 kilometres) have remained in the main belt since their formation, small asteroids are commonly transported to the near-Earth object (NEO) population. However, owing to the lack of direct observational constraints, their size-frequency distribution (SFD)-which informs our understanding of the NEOs and the delivery of meteorite samples to Earth-varies substantially among models.

Young asteroid families as the primary source of meteorites.

Understanding the origin of bright shooting stars and their meteorite samples is among the most ancient of astronomy-related questions, which at larger scales has human consequences. As of today, only approximately 6% of meteorite falls have been firmly linked to their sources (Moon, Mars or asteroid (4) Vesta). Here we show that approximately 70% of meteorites originate from three recent break-ups of D > 30 km asteroids that occurred 5.

A contact binary satellite of the asteroid (152830) Dinkinesh.

Asteroids with diameters less than about 5 km have complex histories because they are small enough for radiative torques (that is, YORP, short for the Yarkovsky-O'Keefe-Radzievskii-Paddack effect) to be a notable factor in their evolution. (152830) Dinkinesh is a small asteroid orbiting the Sun near the inner edge of the main asteroid belt with a heliocentric semimajor axis of 2.19 AU; its S-type spectrum is typical of bodies in this part of the main belt.

Observations, Meteorites, and Models: A Preflight Assessment of the Composition and Formation of (16) Psyche.

Some years ago, the consensus was that asteroid (16) Psyche was almost entirely metal. New data on density, radar properties, and spectral signatures indicate that the asteroid is something perhaps even more enigmatic: a mixed metal and silicate world. Here we combine observations of Psyche with data from meteorites and models for planetesimal formation to produce the best current hypotheses for Psyche's properties and provenance.