NASA is preparing to launch its Perseverance rover, a car-sized nuclear-powered robot, to Mars on July 30.
- After reaching Mars, the rover will perform a harrowing descent to the surface that will require a heat shield, supersonic parachute, and rocket-powered crane.
- NASA is hoping to record much of the descent and landing with six high-definition cameras — possibly returning the first video footage of a spacecraft landing on another planet.
- Perseveance is also packing an experimental helicopter, called Ingenuity, microphones, and high-tech instruments to look for signs of past alien life.
One out of every two spacecraft that humanity rockets toward Mars for a landing never makes it.
Those are the rough odds facing NASA’s upcoming Mars 2020 mission and Perseverance rover, which is currently scheduled to launch from Earth on July 30 and reach the red planet on February 18.
The mission’s $2.4 billion cost, eight years of development, and work by thousands of people will come down to a recurring nightmare for aerospace engineers called the “seven minutes of terror” the entry, descent, and landing phase that all Mars spacecraft must survive in order to explore the world’s surface.
“We’ve got literally seven minutes to get from the top of the atmosphere to the surface of Mars, going from 13,000 mph to zero in perfect sequence, perfect choreography, perfect timing,” Adam Steltzner, chief engineer of the Perseverance mission, said in a 2012 NASA-JPL video about its predecessor robot, the Curiosity rover (which is still going strong). “The computer has to do it all by itself with no help from the ground. If any one thing doesn’t work just right, it’s game over.”
Like the Mars missions before it, Curiosity took some still photos of part of its descent, though no interplanetary spacecraft has ever recorded bonafide video of its landing phase, let alone in high-definition.
With Perseverance, however, the team behind the car-size, nuclear-powered robot is hoping to change that.
“We have something new this time: We’ve taken some ruggedized commercial cameras, and we’ve dispensed them around the spacecraft,” Matt Wallace, deputy project manager of the Mars mission, said during a June 17 press briefing. “Those those cameras will be taking high-definition video of the spacecraft during entry, descent, and landing activity. So we should be able to watch this big parachute inflate supersonically, we should be able to watch the rover deploy and touch down on the surface.”
He added: “This is going to be very exciting; it’s the first time that we have ever been able to see a spacecraft land on another planet.”
The entry, descent and landing camera or “EDLCAM” system on Perseverance is what NASA calls a “discretionary payload.”
The project is effectively a bonus addition to the robot’s main suite of instruments. Those primary tools include a Martian weather-monitoring station, 3D camera, organic compound detectors, percussive rotary drill, and even a device to store the first-ever Martian soil samples (for rocketing back to Earth on a future mission).
Engineers settled on EDLCAM when they realized they had the room and power to add them without cramping the mission’s overarching goal: digging in the Martian dirt for signatures of past microbial alien life.
“They take up very, very little mass and volume,” Wallace told Business Insider during the briefing. “They’re essentially unnoticeable at the spacecraft level.”
Managers of the mission did not custom-build the EDLCAM hardware, though: They ordered some.
The equipment purchased included five 1.3-megapixel and one 3.1-megapixel USB cameras from Point Grey (now owned by FLIR), lenses from Universe Kogaku, a 480 gigabyte solid-state drive, and a small computer that runs Linux, according to Andrew Good, a spokesperson for NASA/JPL-Caltech.
Good noted the cameras are not designed to either fly through the vacuum of space or descend through the atmosphere of another planet. However, the completed spacecraft and its components passed a final review that hinged on vibration, vacuum chamber, and thermal exposure tests before it was tucked into a 15-foot-wide aeroshell and put on top of a rocket.
“Assuming they work as they should, we will have some amazing video from Mars, but we’ll have to see how they work,” Good said of the cameras in an email to Business Insider.
After Perseverance launches and finishes its roughly 200-day cruise to Mars, it will begin the feared seven minutes of terror, which is formally known as the entry, descent, and landing phase of the mission.
About 17 minutes before landing, Perseverance’s protective two-piece aeroshell — the top, or back shell, contains a parachute, and the bottom is a heat shield — will disconnect from a rocket-powered cruise stage.
Ten minutes later, the top-shaped capsule will start plowing through and slowing down in the Martian atmosphere, which is about 1% as thick as Earth’s. However, braking a spacecraft traveling at 13,000 mph generates incredible temperatures ahead of the heat shield that may reach 3,800 degrees Fahrenheit.
After the capsule has bled off most of its speed, and when it’s about 7 miles from the Martian surface, a parachute will pop out from the top of the capsule and further slow it down to about 1,200 mph. Just before this point, Good said, three parachute up-look cameras — part of the six EDLCAM system cameras — will begin recording.
Five miles off the ground, the heat shield will drop off the capsule, exposing a rover down-look camera, which will start recording.
Eighty seconds later, the rover — attached to a rocket-powered descent stage called the “SkyCrane” — will drop away from its back shell. Just before that moment, a down-looking camera on the SkyCrane will start recording, as will an up-looking camera on the rover itself.
A radar system will tell the SkyCrane precisely when to start firing its rocket engines, with the goal of slowing down Perseverance enough to dangle it — like a robotic marionette doll — from a series of cables. Once the rover contacts the surface, the cables will detach, the SkyCrane will fly away, and Perseverance will begin its year-long mission.
“When people look at it, it looks crazy. That’s a very natural thing. Sometimes when we look at it, it looks crazy,” Steltzner said in the 2012 video about Curiosity, which proved the system works. “It is the result of reasoned engineering thought. But it still looks crazy.”
The solid-state drive on the rover will record HD camera footage for as long each device is connected. NASA expects to record about 25,000 images in total, and at frame rates ranging from 12 to 75 images per second. (Standard cell phone footage ranges from 30 to 60 fps.)
“The images will be compressed and returned as video files back to the rover, in a video format similar to that of a typical cell phone,” Good said.
After stashing gigabytes’ worth on unprecedented footage, NASA doesn’t expect to see it on Earth very quickly. “We’ll bring that imagery back over the first couple weeks on the surface,” Wallace said.
Only the rover’s up- and down-looking cameras will remain attached after it lands. However, NASA doesn’t expect to use those cameras — or for them to survive on the red planet.
“[T]hey were not designed to survive the harsh temperature extremes of the Martian surface and thus may not last very long into the surface mission,” Good added.
Perseverance is also packing an experimental helicopter, called Ingenuity, which it will drop off in hopes of attempting the first-ever aerial flights on Mars.
The rover will also harbor two microphones, which engineers will turn on once the robot safely lands. If the devices work, NASA could record the first bonafide audio of Mars, including gusts of wind, the rover’s wheels rolling over soil and rocks, the sounds of drilling, and more.
As Nancy Atkinson wrote for The Planetary Society, previous Mars missions also brought microphones with them, but — what one planetary scientist told Atkinson was a “huge let-down” — they either failed or never activated.
This news was originally published at businessinsider.com