From Ashes to Eternity: the Phoenix Mars Mission
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B-PIA09945.jpgTopographical Context of Phoenix Landing Region53 visiteCaption NASA:"Color coding indicates the topography in this map of the region of Mars from 65 to 72° North Latitude and from 230 to 250° East Longitude. This area was designated "Region D" in the process of evaluating potential Landing Sites for NASA's Phoenix Mars Lander. The location chosen for safe landing sites is within the box bordered with a heavy black line along the western boundary of this region.
Elevation in the region varies from about 3600 meters (11.800 feet) to 4400 meters (14.400 feet) below the zero reference point for Martian Surface Elevation.
The topographical information is from the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor Orbiter".MareKromium
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B-PIA09946-1.jpgPossible Landing Ellipses for Phoenix (1)53 visiteCaption NASA:"Launch date makes a difference in the orientation of ellipses marking where NASA's Phoenix Mars Lander will have a high probability of landing, given the planned targeting for the Spring 2008 Landing Site. This map shows possible landing ellipses for the Aug. 3, 2007, opening of the launch period (the ellipse oriented North-West to South-East) and for launch dates at the middle and end of the 3-week period of launch opportunities.
The map also shows a color-coded interpretation of geomorphic units -- categories based on the surface textures and contours. The yellow-coded area surrounding a crater informally named "Heimdall" appears to have even fewer boulders on the surface than other units. The geomorphic mapping is overlaid on a shaded relief map based on data from the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor orbiter.
The red box indicates the location of an image PIA09947 from the Context Camera on NASA's Mars Reconnaissance Orbiter".MareKromium
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B-PIA09946-2.jpgPossible Landing Ellipses for Phoenix (2)53 visitenessun commentoMareKromium
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B-PIA09947.jpgContext Image of Planned Landing Site53 visiteCaption NASA:"This view covers an area about 27 Km (about 17 miles) wide within the planned landing area for NASA's Phoenix Mars Lander. It was taken by the Context Camera on NASA's Mars Reconnaissance Orbiter and catalogued as image P02_001893_2485_XI_68N126W_061221 from that instrument.
Note the crater near the top (north) of the image. The red box indicates the position of a higher-resolution image PIA09948 of ground texture in this area".MareKromium
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B-PIA09948.jpgSweet Spot for Landing on Mars68 visiteCaption NASA:"This view shows scattered rocks and a polygonal ground texture within the "sweet spot" of the planned landing area for NASA's Phoenix Mars Lander.
This is a subframe, covering a patch of ground about 250 meters (820 feet) across, from a larger image taken by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter on Jan. 1, 2007.
The full image, catalogued as HiRISE image PSP_002170_2485, is centered at 68,3° North Latitude and 232,9° East Longitude".MareKromium
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C-Phoenix-PolarDunes.jpgPossible Northern Scenarios (1) - Dark Dunes and Ice53 visitenessun commentoMareKromium
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C-Phoenix-PolarTexture.jpgPossible Northern Scenarios (2) - Layers58 visitenessun commentoMareKromium
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C-Phonix_Others.jpgPhoenix will not be alone on Mars...53 visitenessun commentoMareKromium
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D-Vastitas-PIA10634.jpgPhoenix Landing Site, from MRO53 visiteNASA's Phoenix Mars Lander is scheduled to land on the Martian Northern Plains near 68° North Lat. and 127° West Long. on May 25, 2008. In preparation for the landing, NASA's Mars Reconnaissance Orbiter has been monitoring weather in the Region around the Landing Site. On April 20, 2008, the orbiter's Mars Color Imager camera captured this view of a large region of Northern Mars that includes the landing target area in the lower right quadrant.
This version of the image indicates the location of the landing ellipse, about 100 Km(approx. 60 miles) long. The Context Camera on the MRO took an image of the Landing Area at the same time the Mars Color Imager took this image.
A dot within the Landing Ellipse marks the location of two active DD visible in the Context Camera image, PIA10633.
When the Mars Color Imager acquired this image, the season in Mars' Northern Hemisphere was late Spring. A few weeks earlier, the Phoenix Landing Site was still covered with seasonal frost left over from the previous winter.MareKromium
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E-PIA10633.jpgDust Devils and Frozen Craters at Phoenix Landing Site (MULTISPECTRUM; credits: Lunexit)53 visiteNASA's Phoenix Mars Lander is scheduled to land on the Martian Northern Plains near 68° North Lat. and 127° West Long. on May 25, 2008. In preparation for the landing, NASA's Mars Reconnaissance Orbiter has been monitoring weather in the Region around the Landing Site.
On April 20, 2008, the orbiter's Context Camera captured this view showing two active DD within the Phoenix Landing Ellipse.
This is a subframe covering an area about 26 Km (approx. 16 miles) on each side (...). It shows two Dust Devils and their shadows. Based on measurement of the shadows cast by the DD, one of the vortices towered about 590 meters (about 1930 feet) with a dust plume extending 920 meters (about 3020 feet) above the surface. The other reached about 390 meters (1280 feet) high, with a dust plume extending to 790 meters (2590 feet). The resolution here is 6 meters (19,7 feet) per pixel.
When the Context Camera acquired this image, the season in Mars' Northern Hemisphere was late Spring. A few weeks earlier, the Phoenix Landing Site was still covered with seasonal frost left over from the previous Winter. White patches in small craters near the center of the picture are areas where the Winter frost remained, even as late as April 20, 2008.
As Spring gives way to Summer, DD are likely to occur more frequently, as local temperatures rise. These two DD observed in late April are among the first of the season. The cameras on the Phoenix Lander might be able to spot additional Dust Devils after the spacecraft arrives, as the Mars Exploration Rover Spirit has been able to do at its Southern Hemisphere Landing Site.
Dust Devils are whirling vortices that have picked up dust from the ground. Such vortices can occur even when no dust is present, but then they are not visible to the cameras onboard the Mars Reconnaissance Orbiter. Such vortices commonly form as hot air rises from the surface on an otherwise generally calm day with little or no breeze. Dust Devils will travel across the surface on the gentle breezes that do occur. Sometimes, DD have been observed by cameras orbiting Mars to create streaks on the ground as they disrupt and pick up dust, though no streaks are observed in this image.
The Mars Orbiter Camera onboard NASA's Mars Global Surveyor orbiter observed Dust Devils — and streaks created by them — throughout its 1997 to 2006 mission. During that time, scientists at Malin Space Science Systems observed more than 12.000 active Dust Devils. They were seen over the full range of elevations and nearly all latitudes on Mars. Dust Devil Streaks were found in Mars Orbiter Camera images as far North as the edge of the North Polar Residual Cap and the dune fields that surround the Region.
However, the northernmost active DD captured by that camera was at 62,2° North Latitude, which is further South than the Phoenix Landing Site.
Another camera on the Mars Reconnaissance Orbiter, the Mars Color Imager, captured a simultaneous, wider-field, color view of the area included in this Context Camera image. That view can be seen at PIA10634.MareKromium
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PHOE-SOL000-HIRISE.jpgThe Descent of Phoenix, from MRO - Sol 054 visiteCaption NASA:"NASA's Mars Phoenix Lander can be seen parachuting down to Mars, in this image captured by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. This is the first time that a spacecraft has imaged the final descent of another spacecraft onto a planetary body.
From a distance of about 310 Km (193 miles) above the surface of the Red Planet, Mars Reconnaissance Orbiter pointed its HiRISE obliquely toward Phoenix shortly after it opened its parachute while descending through the Martian Atmosphere. The image reveals an apparent 10-meter-wide (30-foot-wide) parachute fully inflated. The bright pixels below the parachute show a dangling Phoenix. The image faintly detects the chords attaching the backshell and parachute. The surroundings look dark, but correspond to the fully illuminated Martian surface, which is much darker than the parachute and backshell.
Phoenix released its parachute at an altitude of about 12,6 Km (7,8 miles) and a velocity of 1.7 times the speed of sound".MareKromium
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PHOE-SOL000-PSP_008579_9020.jpgThe Descent of Phoenix, from MRO - Sol 0 (MULTISPECTRUM; credits: Lunexit)53 visiteCaption NASA:"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 Km diameter crater informally called “Heimdall,” and an improved full-resolution image of the parachute and lander (in the inset).
Although it appears that Phoenix is descending into the crater, it is actually about 20 Km in front of it. 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 Km 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 Km, traveling at a ground velocity of 3,4 Km/second, and a distance of 760 Km 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.
The Sun is almost directly behind HiRISE, so the parachute should be casting a shadow onto the slope of the Crater, but we cannot determine which of many dark spots is the shadow until a detailed geometric analysis has been completed". MareKromium
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