Johnson Space Center

Thermally metamorphosed CM chondritic clasts reveal deep interior conditions: Insights from thermometry

We studied four coarse-grained crystalline clasts within CM carbonaceous chondrites to constrain their thermal history and origin. These clasts have near-identical mineralogies, dominated by olivine (Fa 37 or Fa 40 ), with lesser quantities of high-Ca pyroxene (diopside: Fs 10-11...

JuRa: The Juventas Radar on Hera Mission to Probe Internal Structure of Didymos and Dimorphos Asteroids

Abstract JuRa, the Juventas Radar, is the sounding radar of the Hera/ESA mission on cruise to the asteroid Didymos and its moon, Dimorphos. In 2027, it will, for the first time, do direct observation of the internal structure of an asteroid for the benefit of both science and pla...

The parent bodies of Ryugu and Ivuna formed before those of other carbonaceous chondrites

Most carbonaceous chondrite (CC) meteorites contain abundant chondrules, millimeter-scale spherical inclusions of previously molten material. Ivuna-type carbonaceous chondrites (CIs) do not contain chondrules, nor do samples of the carbonaceous asteroid Ryugu. CIs and Ryugu share...

Hippocampal volume changes in astronauts and bilateral vestibulopathy patients

Abstract The hippocampus is a particularly plastic and vulnerable brain structure. Given the modulatory role of the vestibular system on hippocampal function, we hypothesized that altered vestibular stimulation associated with prolonged spaceflight could lead to similar hippocamp...

What Survivors Remembered: Cognitive and Experiential Themes in Trauma Narratives From the Deadliest Mass Shooting in Modern American History

This study examined cognitive and experiential patterns in the trauma narratives of 42 survivors (74% women; M age = 42.1) of the Route 91 Harvest Festival shooting, the deadliest mass shooting in modern American history. We conducted a codebook thematic analysis of written narra...

Ryugu and Bennu preserve primordial isotopic heterogeneity absent from the meteorite record

Ivuna-type (CI) carbonaceous chondrites are commonly used as proxies for the composition of the planet-forming disk because their chemical abundances resemble those of the solar photosphere. However, their isotopic uniformity may reflect pervasive alteration and isotopic averagin...