Related papers: Asteroid Ryugu Before the Hayabusa2 Encounter

This study aims to determine the size, albedo and rotational period of (98943) 2001 CC21, target of the Hayabusa2 extended mission, using thermal data from the Spitzer Space telescope and ground based observations. The Spitzer data were…

In situ observations of small asteroids show that surfaces covered by boulders and coarse terrain are frequent on such bodies. Regolith grain sizes have distributions on approximately mm and cm scales, and the behavior of such large grains…

NASA's OSIRIS-REx and JAXA's Hayabusa2 sample-return missions are currently on their way to encounter primitive near-Earth asteroids (101955) Bennu and (162173) Ryugu, respectively. Spectral and dynamical evidence indicates that these…

Remote sensing observations by Hayabusa2 and laboratory measurements have revealed that the phyllosilicates on asteroid (162173) Ryugu are dehydrated/dehydroxylated due to space weathering. Reactive molecular dynamics simulations were…

When creating asteroid regolith simulant, it is necessary to have a model of asteroid regolith to guide and to evaluate the simulant. We created a model through evaluation and synthesis of the available data sets including (1) the returned…

We analyze images of a rock on Ryugu acquired in situ by MASCam, camera of the MASCOT lander, with the aim of identifying possible carbonaceous chondrite (CC) analogs. The rock's reflectance ($r_{\rm F} = 0.034 \pm 0.003$ at phase angle…

The influence of space weathering on the observed spectra of C-complex asteroids remains uncertain. This has long hindered our understanding of their composition through telescope observations. Multi-band imaging of Ryugu by ONC-T on…

Asteroids (162173) Ryugu and (101955) Bennu observed by Hayabusa2 and OSIRIS-REx share many properties, but spectral observations by the telescopic Optical Navigation Camera (ONC-T) and MapCam detected subtle but significant differences,…

Near-Earth asteroid 162173 (1999 JU3) is the primary target of the Hayabusa-2 sample return mission, and a potential target of the Marco Polo sample return mission. Earth-based studies of this object are fundamental to these missions. We…

Hayabusa2 collected 5.4 g of samples from the asteroid (162173) Ryugu and brought them back to Earth. Obtaining multiband images of these samples with the spectral bands comparable to those used for remote-sensing observations is important…

Near-earth object (NEO) 1998 KY$_{26}$ is a target of the $Hayabusa2\#$ spacecraft, which it will rendezvous with in July 2031. The asteroid is a rapid rotator and has a large out-of-plane nongravitational acceleration. We present deep $g$…

Proximity observations by OSIRIS-REx and Hayabusa2 provided clues on the shape evolution processes of the target asteroids, (101955) Bennu and (162173) Ryugu. Their oblate shapes with equatorial ridges, or the so-called top shapes, may have…

Context. Characterizing mission-accessible asteroids using telescopic observations is fundamental for target-selection and planning for spacecraft missions. Near-Earth asteroids on Earth-like orbits are of particular importance for…

We present an analysis of a stellar occultation event caused by a near-Earth asteroid (98943) 2001 CC21, an upcoming flyby target in the Hayabusa2 extended mission, on March 5, 2023. To accurately determine the asteroid's shape from…

On 24 September 2023, the NASA OSIRIS-REx mission dropped a capsule to Earth containing approximately 120 g of pristine carbonaceous regolith from Bennu. We describe the delivery and initial allocation of this asteroid sample and introduce…

The surfaces of airless bodies such as asteroids are exposed to many phenomena that can alter their physical properties. Bennu, the target of the OSIRIS-REx mission, has demonstrated how complex the surface of a small body can be. In 2019…

We investigated the magnitude-phase relation of (162173) 1999 JU3, a target asteroid for the JAXA Hayabusa 2 sample return mission. We initially employed the international Astronomical Union's H-G formalism but found that it fits less well…

asteroids or comets have received remarkable attention in the world. In small body explorations, especially, detailed in-situ surface exploration by tiny rover is one of effective and fruitful means and is expected to make strong…

The Design Reference Asteroid (DRA) is a compilation of all that is known about the OSIRIS-REx mission target, asteroid (101955) Bennu. It contains our best knowledge of the properties of Bennu based on an extensive observational campaign…

Recent analyses of samples from asteroid (162173) Ryugu returned by JAXA's Hayabusa2 mission suggest that Ryugu and CI chondrites formed in the same region of the protoplanetary disk, in a reservoir that was isolated from the source regions…