"Phoenix" rover is a platform supported by three legs, the platform diameter of 1.5 meters, about 2.2 meters high; its center is a polyhedral instrumentation module, the module left and right sides of the deployment of a positive octagonal solar arrays, spanning 5.52 meters. Compared with the "Mars Polar Lander", "Phoenix" rover's biggest change is to improve the performance of solar cells. "Phoenix" rover carries seven kinds of scientific exploration instruments, NASA staff jokingly referred to them as seven kinds of exploration of the source of life on Mars "secret weapon", they are:
(1) Mechanical arm (RA)
The arm is 2.35 meters long, has four degrees of freedom, and is equipped with serrated blades and corrugated cones at the end, enabling it to excavate a 1-meter-deep pit on the hard surface of the polar permafrost. The robotic arm also adjusts pointing for a camera mounted on the arm, guiding a probe that measures thermal and electrical conductivity into the soil.
(2) Microscope Electrochemistry and Conductivity Analyzer (MECA)
It is a slight improvement on the instruments used in the Mars Explorer program, including a wet chemistry laboratory, optical microscope, atomic force microscope, and a thermal and electrical conductivity detector, four instruments, to detect the elemental composition of the soil and to give samples of the soil. The four instruments include a wet chemistry lab, an optical microscope, an atomic microscope, and a thermal and electrical conductivity detector to examine the elemental composition of the soil and image soil samples.
(3) Thermal and Emission Gas Analyzer (TEGA)
It consists of a differential scanning calorimeter and a mass spectrometer, which are used to observe and record the process of heat absorption and dissipation of soil samples, and to analyze the volatiles released after heating.
(4) Surface Stereo Imager (SSI)
It is used for mapping high-resolution geologic maps and maps of the working area of the robotic arm, multispectral analysis and atmospheric observation. It takes high-resolution, color, stereo images of the terrain at the landing location.
(5) Robotic Arm Camera (RAC)
It is mounted on the excavation shovel at the end of the robotic arm and is used to take high-resolution images of soil samples collected by the robotic arm and to analyze the types and sizes of soil particles.
(6) Mars Descent Imager (MARDI)
It is used to dynamically photograph the surface of Mars during the descent of Phoenix and to survey the geology near the landing site.
(7) Meteorological Station (MS)
This is a new instrument specially developed by the Canadian Space Agency for the Phoenix lander. It consists of two parts: a lidar and a temperature and pressure measurement device, which can monitor the dust and temperature changes in the Martian atmosphere and record the daily weather conditions at the north pole of Mars.
Landing on Mars
Before the exploration mission can be carried out, the Phoenix Mars rover must first successfully land on the surface of Mars, which is filled with dusty material. Here, a couple of things are critical: first, the probe has to accurately enter Mars' orbit, and second, it has to accurately change orbit.
Seven minutes before reaching the Martian atmosphere, the rover and the cruise system separated; half a minute later, the rover turned its heat shield forward by means of a rotating shaft, a process that took 90 seconds; after another five minutes, the rover reached the surface of the Martian atmosphere, at which point it was traveling at a speed of 5.7 kilometers per second and at an altitude of 125 kilometers above the surface of the Martian earth.
The probe then entered the Martian atmosphere. Within three minutes, the probe and the atmosphere friction, not only landing speed greatly reduced, the front surface is also rapidly warmed up, will reach a maximum of 1420 degrees Celsius. At 12.6 kilometers above the Martian surface, the rover opens its rear parachute and relies on it to slow down for three minutes. In 25 seconds after the parachute is opened, the probe throws off the front heat shield and extends the three "legs"; 75 seconds after the parachute is opened, the probe's radar starts to work and feeds back the detected parameters about the probe's distance from the Martian ground, the probe's descending speed and the horizontal speed at the rate of 10 times per second to "The Phoenix carries a computer until it is safe to land.
To 1 kilometer from the surface of Mars, the probe's speed has been reduced to 56 m / s, the probe threw off the parachute, began to free fall; half a second later, the deceleration thrusters began to ignite, the probe on board the computer using radar to collect information to adjust the 12 deceleration thruster impulse fire to slow down the probe's vertical descent speed and the horizontal speed of movement.
When the probe was 30 meters away from the surface of Mars, its descent speed was reduced to about 2 meters per second, and then it slowly descended to the surface of Mars within 12 seconds. The cushioning engine will stop in time when radar detects the Phoenix's "legs" touching the Martian surface.
Unlike the Mars Pathfinder, Courage and Opportunity rovers, which landed on the equatorial regions of Mars via airbags, the Phoenix will be able to land on the surface of the planet. "Phoenix landed in the water-ice-rich north polar region of Mars by braking with decelerating thrusters. Because the mass of the Phoenix is too large, only carrying scientific instruments weighing 59 kilograms, it is difficult to ensure the safety of the soft landing with airbags.
May 25, 16:53 U.S. western time (Beijing time 26 7:53), is located in California's Pasadena Jet Propulsion Laboratory, received from 276 million kilometers away from the "Phoenix" after the landing of the screams, at this time, the wireless signal from Mars to the Earth takes 15.3 minutes. This marks the "Phoenix" after 315 days, crossing the universe 679 million kilometers, successfully landed in the north polar region of Mars. From the pictures sent back later, people can see that the Phoenix Mars Landing Rover is standing on its own, with one "leg" on the surface of Mars.
Photos taken by a camera on the Phoenix's robotic arm give a better idea of what the Phoenix lander was up to: its three legs were resting on a piece of what appeared to be ice, which was apparently the "The Phoenix's boosters blew the dust away to reveal the object, and the white smooth object was most likely a bed of ice.