Phoenix Mars Lander

[Luke_Wilbur]

The Phoenix Mars Lander, which launched in August 2007, is the first project in NASA's Mars Scout missions. The mission's plan is to land in icy soils near the north polar permanent ice cap of Mars and explore the history of the water in these soils and any associated rocks, while monitoring polar climate.

 

Phoenix is slated to land on the Red Planet on Sunday, May 25, 2008.

 

You can watch the landing on NASA TV by clicking:

 

http://www.nasa.gov/multimedia/nasatv/inde...ml?param=public

 

Overview Mars is a cold desert planet with no liquid water on its surface. But in the Martian arctic, water ice lurks just below ground level. Discoveries made by the Mars Odyssey Orbiter in 2002 show large amounts of subsurface water ice in the northern arctic plain. The Phoenix lander targets this circumpolar region using a robotic arm to dig through the protective top soil layer to the water ice below and ultimately, to bring both soil and water ice to the lander platform for sophisticated scientific analysis.

 

The spacecraft and its instruments are designed to analyze samples collected from up to a half-meter (20 inches) deep using its robotic arm. The arm extends forward in this artist's concept of the lander on Mars.

 

 

Phoenix Landing Events Schedule

 

NOTE: The times below for the Phoenix spacecraft events on May 25 are for a nominal scenario. Remaining navigational adjustments before May 25 could shift the times by up to about half a minute. In addition, the times for some events relative to others could vary by several seconds due to variations in the Martian atmosphere and other factors. For some events, a "give or take" range of times is given, covering 99 percent of possible scenarios from the atmospheric entry time. For events at Mars, times are listed in "Earth-receive time" (ERT) rather than "spacecraft event time" (SCET). This means the listed time incorporates the interval necessary for radio signals traveling at the speed of light to reach Earth from Mars. On landing day, May 25, the two planets are 275 million kilometers apart (171 million miles), which means it takes the signal 15 minutes and 20 seconds to reach Earth. For some spacecraft events, engineers will not receive immediate radio confirmation.

 

-- Trajectory correction maneuver opportunity (TCM6X), 8:46 a.m.

-- News briefing, noon

-- Begin non-commentary live television feed from JPL control room, 3 p.m.

-- Begin commentated live television feed from JPL control room, 3:30 p.m.

-- Propulsion system pressurization, 4:16 p.m.

-- Begin "bent-pipe" relay relay (continuous transmission of Phoenix data as it is received) through NASA's Mars Odyssey spacecraft to Goldstone, Calif., Deep Space Network station, 4:38 p.m.

-- Green Bank, W. Va., radio telescope listening for direct UHF from Phoenix, 4:38 p.m.

-- Cruise stage separates, 4:39 p.m.

-- Spacecraft turns to attitude for atmospheric entry, 4:40 p.m.

-- Spacecraft enters atmosphere, 4:46:33 p.m.

-- Likely blackout period as hot plasma surrounds spacecraft, 4:47 through 4:49 p.m.

-- Parachute deploys, 4:50:15 p.m., plus or minus about 13 seconds.

-- Heat shield jettisoned, 4:50:30 p.m., plus or minus about 13 seconds.

-- Legs deploy, 4:50:40 p.m., plus or minus about 13 seconds. -

- Radar activated, 4:51:30 p.m.

-- Lander separates from backshell, 4:53:09 p.m., plus or minus about 46 seconds.

-- Transmission gap during switch to helix antenna 4:53:08 to 4:53:14 p.m.

-- Descent thrusters throttle up, 4:53:12 p.m.

-- Constant-velocity phase starts, 4:53:34 p.m., plus or minus about 46 seconds.

-- Touchdown, 4:53:52 p.m., plus or minus about 46 seconds.

-- Lander radio off 4:54:52 p.m., plus or minus about 46 seconds.

-- Begin opening solar arrays (during radio silence) 5:13 p.m.

-- Begin NASA's Mars Reconnaissance Orbiter playback of Phoenix transmissions recorded during entry, descent and landing, 5:28 p.m. However, data for analysis will not be ready until several hours later.

-- Begin Europe's Mars Express spacecraft playback of Phoenix transmissions recorded during entry, descent and landing, 5:30 p.m. However, data for analysis will not be ready until several hours later.

-- Post-landing poll of subsystem teams about spacecraft status, 5:30 p.m.

-- Mars Odyssey "bent-pipe" relay of transmission from Phoenix, with engineering data and possibly including first images, 6:43 to 7:02 p.m. Data could take up to about 30 additional minutes in pipeline before being accessible. If all goes well, live television feed from control room may show first images as they are received. The first images to be taken after landing will be of solar arrays, to check deployment status.

-- News briefing, 9 p.m.

 

Monday, May 26

-- News briefing, 11 a.m.

 

Tuesday, May 27, through Friday, May 30

Daily news briefings at 11 a.m.

 

Anticipated pace of Mars surface operations

-- If operations proceed relatively smoothly, the first eight to 10 days after landing will be a "characterization phase" of checking out and understanding the performance of the spacecraft's power and thermal systems, as well as the robotic arm and other instruments.

-- At the end of the characterization phase (date tba), the first sample of surface soil will be delivered to the Thermal and Evolved-Gas Analyzer onboard Phoenix.

-- Analysis of soil from the surface in both the Thermal and Evolved-Gas Analyzer and in the Microscopy, Electrochemistry and Conductivity Analyzer will likely take 10 to 15 days if all processes go well. After that, each additional sampling cycle will reach a deeper subsurface level, in increments of about two to three centimeters. At each different layer, collecting and analyzing samples is expected to take 10 to 15 days, barring operational difficulties.

-- How soon the digging reaches the expected icy layer will depend on how far below the surface that layer lies. Estimates in advance of landing range from two to five centimeters. If the ice is at the deeper end of that range, the first analysis of an icy sample could be in July or later.

 

 

In the continental United States, NASA Television's Public, Education and Media channels are carried by MPEG-2 digital C-band signal on AMC-6, at 72 degrees west longitude, Transponder 17C, 4040 MHz, vertical polarization. They're available in Alaska and Hawaii on an MPEG-2 digital C-band signal accessed via satellite AMC-7, transponder 18C, 137 degrees west longitude, 4060 MHz, vertical polarization. A Digital Video Broadcast compliant Integrated Receiver Decoder is required for reception. Analog NASA TV is no longer available.

Edited May 25, 2008 by Luke_Wilbur

[Luke_Wilbur]

Objective 1: Study the History of Water in All its Phases

Currently, water on Mars' surface and atmosphere exists in two states: gas and solid. At the poles, the interaction between the solid water ice at and just below the surface and the gaseous water vapor in the atmosphere is believed to be critical to the weather and climate of Mars. Phoenix will be the first mission to collect meteorological data in the Martian arctic needed by scientists to accurately model Mars' past climate and predict future weather processes.

 

Liquid water does not currently exist on the surface of Mars, but evidence from Mars Global Surveyor, Odyssey and Exploration Rover missions suggest that water once flowed in canyons and persisted in shallow lakes billions of years ago. However, Phoenix will probe the history of liquid water that may have existed in the arctic as recently as 100,000 years ago. Scientists will better understand the history of the Martian arctic after analyzing the chemistry and mineralogy of the soil and ice using robust instruments.

 

Objective 2: Search for Evidence of Habitable Zone and Assess the Biological Potential of the Ice-Soil Boundary

Recent discoveries have shown that life can exist in the most extreme conditions. Indeed, it is possible that bacterial spores can lie dormant in bitterly cold, dry, and airless conditions for millions of years and become activated once conditions become favorable. Such dormant microbial colonies may exist in the Martian arctic, where due to the periodic wobbling of the planet, liquid water may exist for brief periods about every 100,000 years making the soil environment habitable.

 

Phoenix will assess the habitability of the Martian northern environment by using sophisticated chemical experiments to assess the soil's composition of life-giving elements such as carbon, nitrogen, phosphorus, and hydrogen. Identified by chemical analysis, Phoenix will also look at reduction-oxidation (redox) molecular pairs that may determine whether the potential chemical energy of the soil can sustain life, as well as other soil properties critical to determine habitability such as pH and saltiness.

 

Despite having the proper ingredients to sustain life, the Martian soil may also contain hazards that prevent biological growth, such as powerful oxidants that break apart organic molecules. Powerful oxidants that can break apart organic molecules are expected in dry environments bathed in UV light, such as the surface of Mars. But a few inches below the surface, the soil could protect organisms from the harmful solar radiation. Phoenix will dig deep enough into the soil to analyze the soil environment potentially protected from UV looking for organic signatures and potential habitability.

[Luke_Wilbur]

This artist's conception depicts NASA's Phoenix Mars Lander a moment before its touchdown on the arctic plains of Mars. Pulsed rocket engines control the spacecraft's speed during the final seconds of descent.

 

This illustration is part of an animation that can be found at http://www.nasa.gov/mission_pages/phoenix/.../animation.html .

 

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.

 

[Luke_Wilbur]

THE PHOENIX HAS LANDED!!!!

 

Radio signals received at 4:53:44 p.m. Pacific Time (7:53:44 p.m. Eastern Time) confirmed the Phoenix Mars Lander had survived its difficult final descent and touchdown 15 minutes earlier. The signals took that long to travel from Mars to Earth at the speed of light.

 

Mission team members at NASA's Jet Propulsion Laboratory, Pasadena, Calif.; Lockheed Martin Space Systems, Denver; and the University of Arizona, Tucson, cheered confirmation of the landing and eagerly awaited further information from Phoenix later tonight.

 

Among those in the JPL control room was NASA Administrator Michael Griffin, who noted this was the first successful Mars landing without airbags since Viking 2 in 1976.

 

"For the first time in 32 years, and only the third time in history, a JPL team has carried out a soft landing on Mars," Griffin said. "I couldn't be happier to be here to witness this incredible achievement."

 

During its 422-million-mile flight from Earth to Mars after launching on Aug. 4, 2007, Phoenix relied on electricity from solar panels during the spacecraft's cruise stage. The cruise stage was jettisoned seven minutes before the lander, encased in a protective shell, entered the Martian atmosphere. Batteries provide electricity until the lander's own pair of solar arrays spread open.

 

"We've passed the hardest part and we're breathing again, but we still need to see that Phoenix has opened its solar arrays and begun generating power," said JPL's Barry Goldstein, the Phoenix project manager. If all goes well, engineers will learn the status of the solar arrays between 7 and 7:30 p.m. Pacific Time (10 and 10:30 p.m. Eastern Time) from a Phoenix transmission relayed via NASA's Mars Odyssey orbiter.

 

 

This image was acquired at the Phoenix landing site on day 1 of the mission on the surface of Mars, or Sol 0, after the May 25, 2008, landing. The surface stereo imager left acquired this image at 17:07:41 local solar time. The camera pointing was elevation -63.4431 degrees and azimuth 39.9232 degrees.