Indigenous
Aliens
Indigenous Aliens is a day-dream episode I had while reading about the journey of NASA's intelligent robot-car "Perseverance Rover" from its first manufacturing pieces, all the way, to setting up all the connections, finding the right alignment of planets for launching to finally landing far, far away on Mars to explore and trailblaze ahead for humanity.
Mission Context
Launch: Built and operated by NASA's Jet Propulsion Laboratory
Launched on an Atlas V rocket, from Canaveral, Florida,
Earth on July 30, 2020
Landing: Landed on Jezero Crater, Mars on February 18, 2021
Parachute Deploy
Time: ~E +240s
Altitude: ~6~8 mi
Velocity: ~940 mph
Jezero Crater, Mars
Altitude: ~70 ft
Velocity: 17 mph
Rover Separation
Time: ~E +410S
Velocity: 17 mph Vertical
Rover Touchdown
Sky Crane
powered descent
Mars 2020 / Perseverance Rover
Body
The Perseverance Rover's body is called the warm electronics box, or "WEB". Like a car body, the rover body is a strong, outer layer that protects the rover's computer and electronics (which are basically the equivalent of the rover's brains and heart). The body keeps the rover's vital organs protected and temperature-controlled.
Tech Specs
Main job: Carry and protect the computer, electronic, and instrument systems
Length: 10 feet (3 meters)
Width: 9 feet (2.7 meters)
Height: 7 feet (2.2 meters)
Weight/mass: 2,260 pounds / 1,025 kilograms
Structure: Bottom and sides are the chassis frame; top is the rover equipment deck
(its "back"); bottom is the belly pan for the new Sampling and Caching
interior workspace, the belly pan in that front end (about the first 1 1/2
feet from front end) was dropped soon after the rover landed, to expose
it to the Martian atmosphere and make room for sample handling.
Wheels and Legs
Perseverance has six wheels, each with its own motor. The two front and two rear wheels also have individual steering motors, to turn in place a full 360 degrees. The four-wheel steering also lets the rover swerve and curve, making arcing turns.
How the Wheels Move
Like NASA's previous rovers, Perseverance uses a "rocker-bogie" suspension system . The suspension system connects the wheels to the rover and controls how the rover interacts with the Martian terrain. Perseverance is designed to withstand a 45-degree tilt in any direction without tipping over. For added protection, rover drivers avoid terrains that would tilt the rover more than 30 degrees.
The Perseverance rover is the first mission to demonstrate gathering samples from Martian rocks and soil using its drill. The rover stores the sample cores in tubes on the Martian surface. This sample caching process could potentially pave the way for future missions to collect the samples and return them to Earth for intensive laboratory analysis.
The 7-foot-long (2.1 meters) robotic arm can move a lot like your arm. Its shoulder, elbow. and wrist "joints" offer maximum flexibility. Using the arm, the rover works as a human geologist: holding and using science tools with its "hand," or turret. The "hand tools" extract cores from rocks, take micros copic images. and analyze the elemental and mineral composition of Martian rocks and soil. SuperCam can listen for about 3.5 minutes at a time while performing science observations.
This gives the rover the chance to hear the sounds of Mars, such as the high-pitched sound of sand grains over the surface, the wind whistling around the rover mast, and low-pitched howls of dust devils passing by. The microphone also records sounds of Perseverance using its arm, coring rocks, and the wheels crunching against the surface.
The Perseverance rover is the first mission to demonstrate gathering samples from Martian rocks and soil using its drill. The rover stores the sample cores in tubes on the Martian surface. This sample caching process could potentially pave the way for future missions to collect the samples and return them to Earth for intensive laboratory analysis.
Communication
The Perseverance rover has three antennas that serve as its "voice" and its "ears." They are located on the rover equipment deck. Having multiple antennas provides operational flexibility and back-up options in case they are needed.
Ultra-frequency Antenna
Main job: Transmitting Data to Earth through Mars orbiters
Radio frequency: Ultra-High Frequency (UHF) band (about 400 megahertz)
Transmission rates: Up to 2 megabits per second on the rover-to-orbiter relay link
X-band High-Gain Antenna
Main job: Transmitting data directly to and from Earth
Radio frequency: X band (7 to 8 gigahertz)
Transmission rates: 160/500 bits per second or faster to/from the Deep Space
Network's 112-foot-diameter (34-meter-diameter) antennas or
at 800/3000 bits per second or faster to/from the Deep Space
Network's 230-foot-diameter (70 meter-diameter)
X-band Low-Gain Antenna
Main job: Receiving Data
Radio frequency: X band (7 to 8 gigahertz)
Transmission rates: Approximately 10 bits per second or faster from the Deep
Space Network's 112-foot-diameter (34-meter-diameter)
antennas or approximately 30 bits per second or faster from
the Deep Space Network's 230-foot-diameter (70-meter-
diameter) antenna
Assembly
Mission Goals
Search for Life: Explore Jezero Crater, a site believed to have once been a lake and river delta, to find evidence of past microbial life.
Collect Samples: Identify and cache intriguing rock and soil samples in sealed tubes for future retrieval by a subsequent mission and return to Earth.
Prepare for Humans: Test technologies and study the Martian environment to help pave the way for future human and robotic explorers.
By Martian vehicle standards, Perseverance is a standout. Its top speed on flat, hard ground is just under 0.1 mph (152 meters per hour).
On Mars, it's about the journey and destinations--not the speed.
The energy-efficient slow pace consumes less than 200 watts, compared to nearly 150,000 watts for a 200-horsepower car.
