Impacts from MSL Tungsten Blocks and Cruise Stage
Impacts from MSL Tungsten Blocks and Cruise Stage
ESP_029245_1755  Science Theme: Impact Processes
MSL (Curiosity) in cruise configuration jettisoned two 75-kilogram tungsten blocks just before atmospheric entry, used as cruise balance masses. A CTX image was acquired at the predicted impact site for these blocks, revealing four large impact markings that appear very recent.

HiRISE has covered these impact sites with two images (this and showing the impacts in greater detail, and also revealing a large number of new small impact sites. A mosaic was made (50MB) from portions of the two map-projected HiRISE images at 0.5 m/pixel, with white boxes around the four large impacts and a number of smaller impacts.

Other images provide full-resolution, 0.25 m/pixel views of the four large impacts:
Pair of impacts in ESP_029245_1755 (color)
Another impact in ESP_029245_1755 (B&W only)
Impact in ESP_029601_1755 (color)

There is a strewn field of impacts at least 8 kilometers long. A third HiRISE image, ESP_028889_1755 also shows many small fresh-looking impacts, and if it is part of the same strewn field then it was about 12 kilometers long.

We were expecting to see just two impacts sites here--from the tungsten blocks--and it is highly unlikely that these dense blocks broke apart in the atmosphere. The only other source of impacts at nearly the same time and place is the cruise stage itself, which was more likely to break apart in the atmosphere. The impacts were highly oblique, as shown by the asymmetric morphologies of the individual impacts and the elongation of the strewn field.

The large impacts created craters with diameters ranging from 3 - 5 meters diameter, about what was expected from the 75-kilogram tungsten blocks. Which two of the four impacts came from the tungsten blocks? The two central impacts that are close to each other and of similar size probably originated from the tungsten blocks. The other two impacts, which have more asymmetric ejecta, may be from the cruise stage, which broke apart into two main pieces. The many smaller impacts may have been formed by secondaries from the large impacts and additional pieces of the cruise stage.

Although hundreds of new impact sites have been imaged on Mars, we do not know the initial size, velocity, density, strength, or impact angle of the objects. However, for the MSL hardware we do have such information, so study of this impact field will provide data on impact processes and Mars surface and atmospheric properties.

The MSL descent stage later released six 25-kilogram tungsten blocks from a much lower altitude, whose impact markings have been imaged by CTX.

Written by: Alfred McEwen  (5 December 2012)

This is a stereo pair with ESP_031869_1755.
Acquisition date
22 October 2012

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
265.8 km (165.2 miles)

Original image scale range
26.6 cm/pixel (with 1 x 1 binning) so objects ~80 cm across are resolved

Map projected scale
25 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
54°, with the Sun about 36° above the horizon

Solar longitude
193.0°, Northern Autumn

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  1.4°
Black and white
map projected  non-map

IRB color
map projected  non-map

Merged IRB
map projected

Merged RGB
map projected

RGB color
non-map projected

Black and white
map-projected   (1420MB)

IRB color
map-projected   (747MB)

Black and white
map-projected  (810MB)
non-map           (782MB)

IRB color
map projected  (322MB)
non-map           (726MB)

Merged IRB
map projected  (341MB)

Merged RGB
map-projected  (349MB)

RGB color
non map           (659MB)
Map-projected, reduced-resolution
Full resolution JP2 download
Anaglyph details page

B&W label
Color label
Merged IRB label
Merged RGB label
EDR products

IRB: infrared-red-blue
RGB: red-green-blue
About color products (PDF)

Black & white is 5 km across; enhanced color about 1 km
For scale, use JPEG/JP2 black & white map-projected images

All of the images produced by HiRISE and accessible on this site are within the public domain: there are no restrictions on their usage by anyone in the public, including news or science organizations. We do ask for a credit line where possible:

NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Mars Reconnaissance Orbiter for NASA’s Science Mission Directorate, Washington. The HiRISE camera was built by Ball Aerospace and Technology Corporation and is operated by the University of Arizona.