MRO's HiRISE camera acquired this dramatic oblique image
of Phoenix descending on its parachute. Shown here is a a wider view of the full image, showing a 10 kilometer diameter crater informally called "Heimdall" and an improved full-resolution image of the parachute and lander.
Although it appears that Phoenix is descending into the crater, it is actually about 20 kilometers in front of the crater. It is difficult to believe that it is in front of the crater because it is so much smaller, but in reality it is, and that's a good thing because landing on the steep rocky slopes of the crater would have been far too exciting (or risky).
Images from the lander clearly show that it sits on a flat plain, although the rim of Heimdall may be visible on the horizon. Given the position and pointing angle of MRO, Phoenix is at about 13 kilometers above the surface, just a few seconds after the parachute opened. This improved image shows some details of the parachute, including the gap between upper and lower sections. At the time of this observation, MRO had an orbital altitude of 310 kilometers, traveling at a ground velocity of 3.4 kilometers/second, and a distance of 760 kilometers to the Phoenix lander.
The image was rotated to a position that seems approximately parallel to the horizon based on the elongation of Heimdall Crater, but this is not exact. Thus, although Phoenix appears to hang from the parachute at an angle, as if swaying in the wind, the exact geometry has not yet been determined. The parachute image is very sharp as its apparent motion was straight down the HiRISE TDI (time delay integration) columns. However, the surface of Mars was moving at an angle to the TDI columns, and thus is smeared by a few pixels, although the smear is not apparent at the reduced scale of the image shown here.
Map projected scale: No map projected products
Original image scale range: 0.792712 cm/pixel
For those interested in larger, unannotated versions, you may select a TIF image here:
PSP_008579_9020 (2048 samples x 1019 lines; 4MB)
PSP_008579_9020 (4096 samples x 2038 lines; 16MB.)
PSP_008579_9020 Parachute insert (756KB)
TIFF WITH INSET
A TIFF version of the descent image with its inset is PSP_008579_9020_descent
(4096x2038; 24 MB)
ADDITIONAL PRODUCTS AND COLOR
HiRISE has managed to produce a version of this image with a color swath
*NOTE ON NOMENCLATURE
When this caption was written, the name "Heimdall" (with the double "L") was an informal one. Since then, the International Astronomical Union (IAU
) has officially named the crater "Heimdal" with one "L." We decided to keep the original spelling in the caption as part of the historical moment of this incredible image.
Written by: Alfred McEwen (27 May 2008)