Curiosity Mission Updates
Sol 2148: Well I'll be DANed!Written by Melissa Rice on 08.22.2018
NASA's Mars rover Curiosity acquired this image using its Rear Hazard Avoidance Cameras (Rear Hazcams) on Sol 2147 Credit: NASA/JPL-Caltech
Curiosity is probing the subsurface today with its Dynamic Albedo of Neutrons (DAN) instrument. At three different times, Curiosity will use DAN in its "active" mode for 20 minutes, sending pulses of neutrons into the ground beneath the rover, and then listening for the neutrons that are scattered back to the instrument. Hydrogen atoms in water will reduce the energy of the neutrons, so the scattered signal that DAN receives will tell us about how much water might be present in the form of hydrated minerals and amorphous phases, to a depth of 1 m beneath the surface. Curiosity is using DAN multiple times today because the neutron output from the DAN Pulsing Neutron Generator (PNG) has decreased over time (though it is well beyond its expected life), and we hope that integrating over multiple intervals will give the same signal-to-noise ratio that DAN observations had at the start of Curiosity's mission.
About this Blog
These blog updates are provided by self-selected Mars Science Laboratory mission team members who love to share what Curiosity is doing with the public.
Dates of planned rover activities described in these reports are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.