Conjoined Twins
Conjoined Twins
ESP_020894_1395  Science Theme: Landscape Evolution
This image shows a remarkable double crater with a shared rim and North-South trending ejecta deposits. These two craters must have formed simultaneously.

The bolide may have consisted of two objects of the same mass that were loosely connected, perhaps similar to comet 103P/Hartley 2, which the Deep Impact spacecraft (EPOXI mission) encountered on 4 November 2010 (see here). Many more asteroids than comets impact Mars, but asteroids also come in double shapes, like asteroid Itokawa explored by the Japanese Huyabusa mission. The bolide must have separated into two distinct pieces prior to impact in order for two craters to be recognizable.

Written by: Alfred McEwen  (9 February 2011)
Acquisition date
10 January 2011

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
250.0 km (155.4 miles)

Original image scale range
50.0 cm/pixel (with 2 x 2 binning) so objects ~150 cm across are resolved

Map projected scale
50 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
55°, with the Sun about 35° above the horizon

Solar longitude
214.7°, Northern Autumn

For non-map projected images
North azimuth:  96°
Sub-solar azimuth:  17.7°
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   (120MB)

IRB color
map-projected   (56MB)

Black and white
map-projected  (47MB)
non-map           (81MB)

IRB color
map projected  (14MB)
non-map           (61MB)

Merged IRB
map projected  (111MB)

Merged RGB
map-projected  (107MB)

RGB color
non map           (61MB)
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

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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.