A blue edge at the end of the flyby
Processed image. Approximate-true-colour photographic mosaic of four panchromatic LORRI images combined with coarser MVIC colour measurements, acquired in July 2015. Native LORRI scale is about 1 kilometre per pixel and sunlight comes from the right. The layered structure is observed; the colour combination and crop are a presentation of measurements, not four independently photographed blue layers.
NASA/JPL image-use policy · credited mission imagery, resized to WebP
· Original image source · Image licenceBacklighting reveals layers that daylight portraits conceal.
- World
- Pluto
- Case date or period
- Departure observations · July 2015
Look closer
After passing Pluto, New Horizons looked back toward the Sun. Scattered light made thin atmospheric layers visible above the horizon and near rugged terrain.
Follow the evidence
These processed products use different scales and colour treatments. The layered haze is an observed structure, while the palette and composite layout belong to image presentation.
Layers are observed; particle shapes are inferred
Andrew Cheng and colleagues studied haze across LORRI viewing angles and combined the images with ultraviolet extinction measurements. They resolved roughly twenty layers and detected haze more than 200 kilometres above Pluto. Scattering models invoke small particles and aggregates to explain the brightness, while waves generated by wind passing over terrain offer a possible layering mechanism. A search over two to five hours found no measurable change in layer altitude. The layers are photographic evidence; particle structure and wave production are interpretations rather than objects individually resolved in the images.
One observation, two presentations
The paired grayscale views let you compare a lightly processed scene with a layer-enhancing treatment of the same data. Their differences show what contrast processing brings forward. This later departure geometry is also different from the nearer colour mosaic: distance, viewing angle and processing all affect visible structure. A brighter or more distinct band is therefore a question for calibrated analysis, rather than evidence that a layer rose between the two panels.
Sources & further reading
- Pluto Haze in Bands of Blue — NASA Image and Video Library / JPL
- Near-Surface Haze or Fog on Pluto — NASA Image and Video Library / JPL
- Blue Rays: New Horizons High-Res Farewell to Pluto — NASA Image and Video Library / JPL
- Haze in Pluto’s Atmosphere — Cheng and colleagues — Original research paper / author preprint
- Pluto’s haze — two presentations — NASA / New Horizons mission imaging team