A Dust Devil is Born
NASA/JPL/UArizona
A Dust Devil is Born
ESP_066845_1725  Science Theme: 
Dust devils form by rising and rotating warm air pockets. Air near the soil surface can become heated by contact with the warmer ground during the day. The warm air is less dense and rises through the cooler air above it.

As additional air moves inward along the surface to replace the rising pocket, it begins to rotate driven by Coriolis forces, and forms a vortex of spinning air. When the incoming air rises into the column, its rotation picks up speed like a spinning ice skater bring their arms closer to their body. This faster moving air near the soil surface can cause sand grains to bounce and kick up dust which easily rises up into the growing vortex. In this way a dust devil is born.

The study of dust devils is important because they indicate atmospheric conditions such prevailing wind directions and speed. They also periodically cleanse the surface of the dust that gradually settles from the atmosphere. This is something that can be extremely helpful to robotic missions like InSight and Curiosity to keep their solar panels from getting too dusty.

Written by: Mike Mellon  (19 February 2021)
 
Acquisition date
30 October 2020

Local Mars time
14:40

Latitude (centered)
-7.617°

Longitude (East)
11.080°

Spacecraft altitude
264.0 km (164.1 miles)

Original image scale range
26.5 cm/pixel (with 1 x 1 binning) so objects ~79 cm across are resolved

Map projected scale
25 cm/pixel and North is up

Map projection
Equirectangular

Emission angle
3.5°

Phase angle
37.4°

Solar incidence angle
41°, with the Sun about 49° above the horizon

Solar longitude
305.4°, Northern Winter

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  343.3°
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   (338MB)

IRB color
map-projected   (186MB)

JP2 EXTRAS
Black and white
map-projected  (127MB)
non-map           (213MB)

IRB color
map projected  (37MB)
non-map           (165MB)

Merged IRB
map projected  (87MB)

Merged RGB
map-projected  (83MB)

RGB color
non map           (163MB)
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.