Movie of Phoenix Mars Lander's Telltale from the First Half of the Primary Mission
The Meteorological Station on NASA's Phoenix Mars Lander includes a telltale to gauge wind direction and speed. This animation portrays changes in wind during the course of a Martian day, based on a selection of 271 images from the 1,225 total telltale images captured by the lander's Surface Stereo Imager through the mission's first 45 Martian days, or sols, (May 26 to July 10, 2008). The images were selected to best represent the time period from 10 a.m. to 7 p.m. local true solar time at the Phoenix landing site, in two-minute intervals.
The camera took the images through a blue filter designed to look at objects on the deck. The images have been stretched to improve contrast and ratioed to constant optical depth and lighting conditions on the telltale mirror. In this animation, the individual images have been shown superimposed upon a full image of the telltale from Sol 13 for context.
The telltale is about 10 centimeters (4 inches) tall.
As the day progresses, the position of the bob can be seen to change position as the winds at the Phoenix Landing site change direction. The change in lighting conditions can also be observed as a darkening of the telltale mirror and cross. Variability in the wind speed at certain times of day shows up as rapid motions of the telltale bob. This animation is only possible as a result of the consistency of the observed surface winds at the Phoenix Landing site which vary more significantly over the course of a day than they do from one day to the next.
The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.
Video Credit: Image NASA/JPL-Caltech/University of Arizona/Texas A&M University/CSA