Posted on 05/26/2008 8:20:13 PM PDT by blam
Camera On Mars Orbiter Snaps Phoenix During Landing
NASA's Mars Phoenix Lander can be seen parachuting down to Mars, in this image captured by the High Resolution Imaging Science Experiment camera on NASA's Mars Reconnaissance Orbiter. (Credit: NASA/JPL-Calech/University of Arizona)
ScienceDaily (May 27, 2008) — A telescopic camera in orbit around Mars caught a view of NASA's Phoenix Mars Lander suspended from its parachute during the lander's successful arrival at Mars Sunday evening, May 25.
The image from the High Resolution Imaging Science Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter marks the first time ever one spacecraft has photographed another one in the act of landing on Mars.
Meanwhile, scientists pored over initial images from Phoenix, the first ever taken from the surface of Mars' polar regions. Phoenix returned information that it was in good health after its first night on Mars, and the Phoenix team sent the spacecraft its to-do list for the day.
"We can see cracks in the troughs that make us think the ice is still modifying the surface," said Phoenix Principal Investigator Peter Smith of the University of Arizona, Tucson. "We see fresh cracks. Cracks can't be old. They would fill in."
Camera pointing for the image from HiRISE used navigational information about Phoenix updated on landing day. The camera team and Phoenix team would not know until the image was sent to Earth whether it had actually caught Phoenix.
"We saw a few other bright spots in the image first, but when we saw the parachute and the lander with the cords connecting them, there was no question," said HiRISE Principal Investigator Alfred McEwen, also of the University of Arizona.
"I'm floored. I'm absolutely floored," said Phoenix Project Manager Barry Goldstein of NASA's Jet Propulsion Laboratory, Pasadena, Calif. A team analyzing what can be learned from the Phoenix descent through the Martian atmosphere will use the image to reconstruct events.
HiRISE usually points downward. For this image, the pointing was at 62 degrees, nearly two-thirds of the way from straight down to horizontal. To tilt the camera, the whole orbiter must tilt. Mars Reconnaissance Orbiter was already pointed toward the expected descent path of Phoenix to record radio transmissions from Phoenix.
McEwen said, "We've never taken an image at such an oblique angle before."
The landing
From a distance of about 760 kilometers (472 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 corresponds 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 kilometers (7.8 miles) and a velocity of 1.7 times the speed of sound.
The tasks for May 27 for Phoenix include checkouts of some instruments and systems, plus additional imaging of the lander's surroundings.
pted from materials provided by National Aeronautics And Space Administration.
Probably too thin an atmosphere to develop the ionized plasma around the spacecraft.
Yup, overperforming. Just like the Mars Rovers, which stayed functional WAY longer then they were supposed to. In fact, isn’t one of those still “alive”?
The Pheonix is supposed to keep working for 3 months. Anyone want to take an over/under on one year?
It used up-thrusting propulsion jets to offset Martian terminal velocity.
I wish there was some frame of reference of size/distance for the Mars photos. I can’t tell if those polygon shapes are 3 foot across or 20 feet across.
The parachutes’s open, so the craft must be under 8 miles altitude; the orbiter was 472 miles up, so the distance between the two had to be at least 464 miles! And all this around a planet that’s, what, 100 million miles away at the moment.
Wow. Well done, NASA.
It’s above the Martian arctic circle. Come the winter, it will receive no sunlight.
Description of how freeze/thaw cycles form polygons.
http://www.crrel.usace.army.mil/permafrosttunnel/1g3g_Wedge_Formation.htm
They found what appears to be a crushed beer can.
Think you are correct about atmospheric density.
From another site:
It was once believed that Mars had an atmosphere much like Earth’s and that if we could find a way to get there, we could breath Martian air. As often happens, knowledge brings a new outlook. Composition of the Martian air is 95% Carbon Dioxide, 3% nitrogen and trace amounts of oxygen and water. The density of the Martian atmosphere is only 1% of Earth.
Though there is water crystals in the atmosphere, no rain ever falls on Mars. The atmosphere is too cold and there is too little water in them to produce rain. There is so little water in the atmosphere that if all of it were to fall at once, it would make a layer less than 1/2000th of an inch thick. Despite such little water, fog does form in some valleys and on really cold nights there is frost. Around the poles, there is carbon dioxide snow!
It is believed that Mars had a very different atmosphere in its distant past. At one time, the planet’s atmosphere may have been much more like Earth’s is now. Apparently, Mars has changed a great deal in it’s history.
Maybe they can figure this out from the last time. http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/20040524a/site_B115_navcam_180_cyl_L-B118R1_br2.jpg
Piece of the ark?
The first close-up color image of the northern arctic region on Mars was taken by the Mars Phoenix Lander about two hours after its arrival on the Red Planet May 25. Visible is polygonal structure, which may indicate regions where water ice lies just below the surface. Similar polygons are found in Earth’s polar regions, where they typically form from cycles of freezing and thawing.
http://www.sciencenews.org/view/generic/id/32580/title/Touchdown%21_Phoenix_lands_on_Mars
Did the Ark make it to Mars? :-)
Yep, on FR we wondered what the hell were railroad ties doing on Mars. I’ll go look for the thread.
The photo... 
NASA released
The classified version... 
not released!
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