Dust devil tracks and wind streaks in the North Polar Region of Mars: A study of the 2007 Phoenix Mars Lander Sites

摘要

The 65 - 72 latitude band of the North Polar Region of Mars, where the 2007 Phoenix Mars Lander will land, was studied using satellite images from the Mars Global Surveyor (MGS) Mars Orbiter Camera Narrow-Angle (MOC-NA) camera. Dust devil tracks (DDT) and wind streaks (WS) were observed and recorded as surface evidence for winds. No active dust devils (DDs) were observed. 162 MOC-NA images, 10.3% of total images, contained DDT/WS. Phoenix landing Region C ( 295 - 315W) had the highest concentration of images containing DDT/WS per number of available images (20.9%); Region D ( 130 - 150W) had the lowest (3.5%). DDT and WS direction were recorded for Phoenix landing regions A ( 110 - 130W), B ( 240 - 260W), and C to infer local wind direction. Region A showed dominant northwest-southeast DDT/WS, Region B showed dominant north-south, east-west and northeast-southwest DDT/WS, and region C showed dominant westorthwest-east/southeast DDT/ WS. Results indicate the 2007 Phoenix Lander has the highest probability of landing near DDT/ WS in landing Region C. Based on DDT/ WS linearity, we infer Phoenix would likely encounter directionally consistent background wind in any of the three regions.