Landing Conditions
This figure shows the entry vehicle deceleration in g's along its
flight path during the entry phase of the mission. As the probe enters at 7.5 km/second,
the deceleration forces produced by the atmosphere range from less than 10 micro g at time
0 (160 km) to about 20 g at 100 seconds (25 km). The deceleration pulse produced by
parachute deployment is clearly seen at 185 seconds (10 km).
This figure shows entry vehicle deceleration in g along its flight path
during the entry phase of the mission. Deceleration is plotted in logarithmic coordinates
to reveal accelerations in the range 0.00001 to 20 g. These measurements allow the
atmospheric density, pressure and temperature profiles to be calculated.
This figure shows RSS acceleration from the three Pathfinder science acceleromaters plotted as a function of time during the Pathfinder spacecraft landing. Specific features are airbag deployment (1194 seconds), RAD motor firing (1198 seconds), the cutting of the bridal (1200 seconds), the first bounce (1204 seconds), and the second bounce (1210 seconds). 15 bounces are clearly shown before the high rate (32 Hz) data sampling period ends. Pathfinder is thought to have bounced and rolled for another 1 minute before coming to rest. The height of the peak shows how hard the lander bounced, and the time between peaks shows how high the bounce was (For example 6 seconds =3D 16.7 m, 5 seconds =3D 11.6 m, 4 seconds =3D 7.4 m, 3 seconds =3D 4.2 m, and 2 seconds =3D 1.9 m).
This figure shows the variation with time of pressure
(dots) measured by the Pathfinder MET instrument during landing period of Figure 1. The
two diamonds indicate the times of bridal cutting and 1st impact. The overall trend in the
data is of pressure increasing with time. This is almost certaily due to the lander
rolling downhill by roughly 10 m. The spacing of the horizontal dotted lines indicates the
pressure change expected from 10 m changes in altitude. Bounces may also be visible in the
data.