Spring Fans at Macclesfield
Spring Fans at Macclesfield
ESP_064469_0945  Science Theme: Seasonal Processes
Every Martian spring, fans of dust are blown out from under the seasonal layer of carbon dioxide ice that forms a polar cap over the winter.

Gas blowing out from under the ice carries with it a load of dust that is deposited on the surface in a direction determined by the wind at the time of the eruption. Like windsocks, these fans in a polar area we’ve dubbed Macclesfield, record the direction that the wind was blowing.

A citizen science task at Planet Four enlists the public to outline the fans. Their measurements go into a data base that will ultimately help us to understand weather on Mars.

Written by: Candy Hansen (narration: Tre Gibbs)  (28 May 2020)
Acquisition date
27 April 2020

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
245.2 km (152.4 miles)

Original image scale range
49.1 cm/pixel (with 2 x 2 binning) so objects ~147 cm across are resolved

Map projected scale
50 cm/pixel

Map projection

Emission angle

Phase angle

Solar incidence angle
86°, with the Sun about 4° above the horizon

Solar longitude
191.1°, Northern Autumn

For non-map projected images
North azimuth:  127°
Sub-solar azimuth:  32.3°
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   (153MB)

IRB color
map-projected   (92MB)

Black and white
map-projected  (86MB)
non-map           (113MB)

IRB color
map projected  (46MB)
non-map           (91MB)

Merged IRB
map projected  (158MB)

Merged RGB
map-projected  (154MB)

RGB color
non map           (97MB)
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.