Help Shape the Future of Space Exploration

Join The Planetary Society Now  arrow.png

Join our eNewsletter for updates & action alerts

    Please leave this field empty
The Bruce Murray Space Image Library

Shadows within shadows: Dark material on the floor of a crater in Mercury's high north

Filed under pretty pictures, Mercury, MESSENGER

Go Back

Shadows within shadows: Dark material on the floor of a crater in Mercury's high north The top left panel shows a view of an unnamed crater in Mercury’s north polar region, with the crater rim outlined in pink and the edge of a low-altitude image in green. The crater has a diameter of 18 kilometers. In the large bottom panel, a different stretch has been applied to the same low-altitude image, revealing details of the shadowed surface inside the crater. In particular, as highlighted with yellow arrows in the top right panel, the image reveals a region inside the crater that has a lower reflectance. The edge of the low-reflectance region has a sharp and well-defined boundary, even as imaged at this highest resolution of 24 m/pixel. The sharp boundary suggests that the low-reflectance material is sufficiently young to have preserved a sharp boundary against lateral mixing by impact craters. The sharp boundary matches the location predicted by temperature models for the stability of a surficial layer of volatile, organic-rich material tens of centimeters thick that overlies a thicker layer of water ice.


Original page on MESSENGER website

Original image data dated on or about August 31, 2014.

Most NASA images are in the public domain. Reuse of this image is governed by NASA's image use policy.


Other Related Images


Leave a Comment:

You must be logged in to submit a comment. Log in now.

Space in Images

Pretty pictures and
awe-inspiring science.

See More

Join The Planetary Society

Let’s explore the cosmos together!

Become a Member

Connect With Us

Facebook, Twitter, YouTube and more…
Continue the conversation with our online community!