One of the most rewarding parts of a career in planetary science is involvement with NASA missions.  Below is a brief description of the mission teams I've worked on as a student or postdoc and how I've used the data.




HiRISE (High Resolution Imaging Science Experiment) is one of six scientific instruments aboard the Mars Reconnaissance Orbiter.  It is a camera that takes images of the Martian surface with a resolution of ~30 cm/pixel.  HiRISE stereo pair images can be converted into digital elevation models with vertical resolution of ~1m. 


I've developed a technique to analyze the icy stratigraphy we see in HiRISE images at the Martian poles.  Using this technique, I quantified the confidence with which an orbital signal can be detected in the stratigraphy.  I've also used HiRISE to study viscous deformation of icy topography in the polar regions.  I found viscous flow to be negligible for craters at the north pole, but extremely important for steep cliffs (right) of ice that host avalanches.

3D reconstructions of cliffs at the edge of the north polar layered deposits made from HiRISE stereo images (top).  These cliffs host avalanches of frost/dust (bottom, HiRISE image ESP_016228_2650)

Simulated west-facing view of Ahuna Mons on Ceres reconstructed from Dawn Framing Camera stereo images.


Dawn is a spacecraft that orbited two large bodies in the asteroids belt: Vesta in 2011 and 2012 and Ceres in 2015 through the present.  It has three scientific instruments: a camera, a visible/infrared spectrometer, and a gamma ray/neutron detector. 

I've used Dawn data to study cryovolcanism on Ceres.  Dawn observed Ahuna Mons (left), a prominent mountain thought to be a cryovolcanic dome.  I showed that post-emplacement viscous relaxation is likely an important mechanism in modifying cryovolcanoes on Ceres, thus explaining why we don't observe a plethora of older prominent volcanoes all over the surface.   My work thus constrains the cryovolcanic history of the planet.


GRAIL (Gravity Recovery and Interior Laboratory) was a mission launched in 2011(right) that measured the gravity field of the Moon extremely accurately.  The mission consisted of two spacecraft, Ebb and Flow, orbiting the Moon in sequence.  The measurement made is the distance between the two spacecraft, which can be translated into gravitational acceleration.

I used GRAIL data to quantify lunar volcanism on the Moon that is obsucred from view by overlying bright material by searching for the gravitational signatures of such hidden deposits.  I found that early lunar volcanism is an important component in lunar thermal history.  I've also used the gravity data to study the nature of isostasy on the Moon, which I argued must involve the lunar mantle in compensation. 

Artist depiction of the two GRAIL spacecraft in lunar orbit.

Rectangular cylindrical projection of LOLA topography centered on the Moon's farside.