Bright hollows in a scorched landscape
Event image. Narrow-angle camera photograph of western Zeami basin on 2 March 2015, originally 20 metres per pixel over a roughly 20-kilometre field. North points down. Bright hollow margins and dark floors respond to the viewing and illumination geometry; this is not a before-and-after growth sequence.
NASA/JPL image-use policy · credited mission imagery, resized to WebP
· Original image source · Image licenceSmall depressions became one of MESSENGER’s unexpected discoveries.
- World
- Mercury
- Case date or period
- Photographs · 2012–2015
Look closer
Mercury’s hollows are irregular, often bright-edged depressions that occur in groups. Some high-resolution views show far fewer small craters inside them than on the surrounding surface.
Follow the evidence
The comparison supports questions about relative age and the loss of volatile material. It does not supply a direct movie of a hollow forming; the images show different sites.
A bright floor does not identify a mineral
David Blewett and colleagues compared geological settings and reflectance spectra of Mercury’s hollows. They considered loss of volatile-bearing material, including destruction of a darkening sulfide component, alongside changes in grain size and scattering texture. Removing a reddish dark component could leave a brighter, bluer surface, but the colour alone does not identify the lost substance. Associations with excavated material and sun-facing slopes constrain the mechanism; neither a bright margin nor sparse cratering records hollow growth directly.
A field guide to different hollow fields
Move from the etched floor of Sander to Balanchine’s slumped walls, then compare Scarlatti’s sparse cratering with the surrounding ground. These are separate places photographed under different lighting, not successive frames of one depression forming. The Balanchine exposure belongs to a stereo acquisition, while the displayed product is one camera view. The existing Atlas marker still identifies the Timgad image centre rather than relocating the entire collection to the newest photograph.
Sources & further reading
- A Field of Hollows — NASA Image and Video Library / JPL
- The Young Ones — NASA Image and Video Library / JPL
- Goodbye, Hollows — NASA Image and Video Library / JPL
- Mercury’s hollows: Constraints on formation and composition — Blewett and colleagues — Original investigators / research publisher
- Sander’s Hollows! — NASA / MESSENGER mission imaging team
- Hollows in Balanchine Crater — NASA / MESSENGER mission imaging team