Pristine Dust Deposits in Syria Planum
NASA/JPL/University of Arizona
Pristine Dust Deposits in Syria Planum
ESP_061126_1680  Science Theme: Aeolian Processes
twitter  •  tumblr

HICLIP
1080p (MP4)
Audio (MP3)

WALLPAPER
800
1024
1152
1280
1440
1600
1920
2048
2560
2736
2880
4500
4K
8K
10K

HIFLYER
PDF (11 x 17)

HISLIDES
PowerPoint
Keynote
PDF

Wind-blown deposits known as transverse aeolian ridges (TARs) are frequently visible in images of the Martian tropics. They are bright ripples with heights of 2.6 meters and spacing that averages 47 meters. The TARs generally appear inactive and eroded, sometimes cratered or littered with boulders from nearby impacts and avalanches.

In Syria Planum, unusual bright deposits might be accumulations of dust blown from higher to lower elevations by nighttime slope winds, reaching speeds of up to 50 meters per second. These dust deposits resemble TARs in height and spacing but with a distinct shape from other TARs. A close up view shows that the deposits form pyramidal features with steep faces on the upwind sides (wind is blowing from the top of the picture) and tapered slopes in the downwind direction. Ridges form where the “pyramids” line up together, and the spacing of the ridges appears to be controlled by the length of the “pyramids.”

These observations suggest that TARs elsewhere on Mars may have formed in a similar fashion, perhaps millions of years ago when the atmosphere was more active. They also may be forming in Syria Planum today.

Written by: Paul Geissler (narration: Tre Gibbs)  (14 October 2019)
 
Acquisition date
11 August 2019

Local Mars time
15:00

Latitude (centered)
-11.793°

Longitude (East)
251.027°

Spacecraft altitude
253.0 km (157.2 miles)

Original image scale range
25.6 cm/pixel (with 1 x 1 binning) so objects ~77 cm across are resolved

Map projected scale
25 cm/pixel and North is up

Map projection
Equirectangular

Emission angle
8.1°

Phase angle
61.9°

Solar incidence angle
56°, with the Sun about 34° above the horizon

Solar longitude
64.8°, Northern Spring

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  43.9°
JPEG
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

JP2
Black and white
map-projected   (666MB)

IRB color
map-projected   (389MB)

JP2 EXTRAS
Black and white
map-projected  (327MB)
non-map           (389MB)

IRB color
map projected  (132MB)
non-map           (333MB)

Merged IRB
map projected  (179MB)

Merged RGB
map-projected  (172MB)

RGB color
non map           (322MB)
ADDITIONAL INFORMATION
B&W label
Color label
Merged IRB label
Merged RGB label
EDR products
HiView

NB
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

USAGE POLICY
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

POSTSCRIPT
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.