Spiders Found by Citizen Scientists
Spiders Found by Citizen Scientists
ESP_047487_1005  Science Theme: Seasonal Processes
Mars has a seasonal polar cap composed of dry ice. In the spring, the ice turns into gas and carves spidery channels in the ground, unlike anything on Planet Earth!

To investigate more locations where these unique features occur, we enlisted citizen scientists to go through the Mars Reconnaissance Orbiter Context Imager’s images and identify regions with this terrain. This HiRISE image highlights one of the locations identified through the Planetfour: Terrains website. The “spiders” here are surrounded by ground described as “basketball terrain” because of its textural similarity to the stippled surface of a basketball.

Written by: Candy Hansen  (20 October 2016)
Acquisition date
12 September 2016

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
250.0 km (155.4 miles)

Original image scale range
25.0 cm/pixel (with 1 x 1 binning) so objects ~75 cm across are resolved

Map projected scale
25 cm/pixel

Map projection

Emission angle

Phase angle

Solar incidence angle
69°, with the Sun about 21° above the horizon

Solar longitude
221.6°, Northern Autumn

For non-map projected images
North azimuth:  105°
Sub-solar azimuth:  37.4°
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   (882MB)

IRB color
map-projected   (491MB)

Black and white
map-projected  (333MB)
non-map           (592MB)

IRB color
map projected  (116MB)
non-map           (507MB)

Merged IRB
map projected  (236MB)

Merged RGB
map-projected  (216MB)

RGB color
non map           (442MB)
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/JPL/University of Arizona

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.