The Perseverance — Part 1 (The Mars 2020 Mission)
By: Kunika Valecha
Tags: Mars Mission, NASA, Mars, Ingenuity, Perseverance

When the news of Perseverance rover landing successfully on the surface of Mars rolled out, I wondered what is unhackneyed about it. There are numerous rovers that have been sent to the planet, so why is everyone excited for this nth one. On exploring a bit more, I came across the term ‘Ingenuity’.

NASA’s Perseverance rover could fundamentally change how we see the red planet and our place in the universe over the course of its mission, as it seeks out signs of past life. But it is not alone. A hitchhiker came along for the journey that could also make history in its own right.

What is Ingenuity?

Strapped to the the Perseverance rover is a tiny, lightweight helicopter. Named Ingenuity, the flying envoy is experimental technology. Beginning this spring, it will attempt to take to the Martian skies, marking the first powered flight of any craft on another planet.

This illustration made available by NASA envisions the Ingenuity helicopter on Mars after launching from the Perseverance rover, background left. It will be the first aircraft to attempt controlled flight on another planet.

If the test flights are successful — or even if they’re not — Ingenuity could open up tantalizing new possibilities for how we explore the red planet and other parts of the solar system in the future.

The Ingenuity team has honed the helicopter’s design here on Earth, doing their best to simulate the Martian environment in special pressurized chambers. To combat the gravity issue, they added a tether to the top of the helicopter to reduce its weight.

To mitigate these differences, Ingenuity was built from very light materials, but with longer, stiffer rotors that spin faster than they would need to on Earth. The space helicopter weighs 4 pounds, sits about 19 inches tall, and its rotor system spans about 4 feet.

How will Ingenuity probe without Maps?

GPS relies on a network of satellites in orbit around our planet, which doesn’t exist on Mars. Furthermore, Mars has a weak and irregular magnetic field. On Earth, compasses rely on the planet’s strong magnetic field to orient themselves.

Instead, Ingenuity will use an optical navigation system. Essentially, the craft will snap pictures of its surroundings as it flies to detect and identify features on the planet. It will rely on those images to orient itself and figure out how to get where it’s programmed to go.

How will Ingenuity charge itself without electricity?

All spacecraft on Mars struggle with: power. While a rover can rest in the sunshine to charge its batteries on solar power if it needs to, a helicopter requires more and constant power to keep its body airborne. It’s a balancing act with weight.

Ingenuity will rely on solar power, as other options are prohibitively heavy. It will operate autonomously, but use the Perseverance rover to relay data and receive commands from mission control back on Earth.

Why is it difficult to land a drone on Mars?

Mars has an atmosphere that is about 1% the volume of Earth’s. That means that anything on Mars experiences significantly less pressure than on Earth. The gravity on Mars is also roughly a third of that on Earth.

On Mars, successful test flights could mean that helicopters will become an important part of the suite of exploration tools. They would add a bird’s-eye view to our understanding of the planet, and could serve as a scout for rovers — or even humans, one day. They could scope out the landscape much more quickly than a rover and determine whether it was navigable terrain, or even worth exploring.

The another aspect which makes Percy a step ahead of previous probes is its ability to defeat the ‘Mars Curse’ and reach to unexplored regions on Mars.

What is Mars Curse?

On diving deeper into timeline of landing rovers on Mars, you will discover that around 60% of human attempts to explore the red planet got failed. Mars eats spacecraft for breakfast. It is the pitcher plant of the Solar System. It’s not picky. It eats orbiters, landers, even gentle and harmless flybys. Sometimes it kills them before they’ve even left Earth orbit.

In the early 1960s, the Soviets tried to capture the space exploration high ground to send missions to Mars. They started with the Mars 1M probes. They tried launching two of them in 1960, but neither even made it to space. Another in 1962 was destroyed too.

They got close with Mars 1 in 1962, but it failed before it reached the planet, and Mars 2MV didn’t even leave the Earth’s orbit.

Five failures, one after the other, that must have been heartbreaking. Then the Americans took a crack at it with Mariner 3, but it didn’t get into the right trajectory to reach Mars.

Finally, in 1964 the first attempt to reach Mars was successful with Mariner 4. We got a handful of blurry images from a brief flyby.

For the next decade, both the Soviets and Americans threw all kinds of hapless robots on a collision course with Mars, both orbiters and landers. There were a few successes, like Mariner 6 and 7, and Mariner 9 which went into orbit for the first time in 1971. But mostly, it was failure. The Soviets suffered 10 missions that either partially or fully failed. There were a couple of orbiters that made it safely to the Red Planet, but their lander payloads were destroyed. That sounds familiar.

Finally, the Americans saw their greatest success in Mars exploration: the Viking Missions. Viking 1 and Viking 2 both consisted of an orbiter/lander combination, and both spacecraft were a complete success.

View of Mars from Viking 2 lander, September 1976. (NASA/JPL-Caltech)

Was the Mars Curse over? Not even a little bit. During the 1990s, the Russians lost a mission, the Japanese lost a mission, and the Americans lost 3, including the Mars Observer, Mars Climate Orbiter and the Mars Polar Lander.

The 2000s have been good. Every single American mission has been successful, including Spirit and Opportunity, Curiosity, the Mars Reconnaissance Orbiter, and others.

Mars Landing Sites, Including Perseverance: This map of Mars shows the landing site for NASA’s Perseverance rover in relation to those of previous successful Mars missions.

But the Mars Curse just won’t leave the Europeans alone. It consumed the Russian Fobos-Grunt mission, the Beagle 2 Lander, and now, poor Schiaparelli. Of the 20 missions to Mars sent by European countries, only 4 have had partial successes, with their orbiters surviving, while their landers or rovers were smashed.

Is there something to this curse? Is there a Galactic Ghoul at Mars waiting to consume any spacecraft that dare to venture in its direction?

Flying to Mars is tricky business, and it starts with just getting off Earth. The escape velocity you need to get into low-Earth orbit is about 7.8 km/s. But if you want to go straight to Mars, you need to be going 11.3 km/s. Which means you might want a bigger rocket, more fuel, going faster, with more stages. It’s a more complicated and dangerous affair.

Your spacecraft needs to spend many months in interplanetary space, exposed to the solar winds and cosmic radiation.

Arriving at Mars is harder too. The atmosphere is very thin for aerobraking. If you’re looking to go into orbit, you need to get the trajectory exactly right or crash onto the planet or skip off and out into deep space. And if you’re actually trying to land on Mars, it’s incredibly difficult. The atmosphere isn’t thin enough to use heatshields and parachutes like you can on Earth. And it’s too thick to let you just land with retro-rockets like they did on the Moon. Landers need a combination of retro-rockets, parachutes, aerobraking and even airbags to make the landing. If any one of these systems fails, the spacecraft is destroyed, just like Schiaparelli.

Schiaparelli lander’s planned descent sequence. Image: ESA/ATG medialab

But our scientists are yet here to gauntlet of the Mars Curse in form NASA’s Perseverance rover. It attempted its long-awaited landing at Jezero Crater on February 18th. The people at NASA have given the Perseverance rover some finely-tuned tools to get it to the Martian surface safely and to beat the Mars curse.

What is Jezero Crater?

This illustration shows Jezero Crater — the landing site of the Mars 2020 Perseverance rover — as it may have looked billions of years go on Mars, when it was a lake. An inlet and outlet are also visible on either side of the lake.

NASA chose Jezero Crater as the landing site for the Perseverance rover. Scientists believe the area was once flooded with water and was home to an ancient river delta. The process of landing site selection involved a combination of mission team members and scientists from around the world, who carefully examined more than 60 candidate locations on the Red Planet. After the exhaustive five-year study of potential sites, each with its own unique characteristics and appeal, Jezero rose to the top.

Jezero Crater tells a story of the on-again, off-again nature of the wet past of Mars. More than 3.5 billion years ago, river channels spilled over the crater wall and created a lake. Scientists see evidence that water carried clay minerals from the surrounding area into the crater lake. Conceivably, microbial life could have lived in Jezero during one or more of these wet times. If so, signs of their remains might be found in lakebed or shoreline sediments. Scientists will study how the region formed and evolved, seek signs of past life, and collect samples of Mars rock and soil that might preserve these signs.

Jezero Crater is 28 miles (45 kilometers) wide, and is located on the western edge of a flat plain called Isidis Planitia, which lies just north of the Martian equator. The landing site is about 2,300 miles (3,700 kilometers) from Curiosity’s landing site in Gale Crater.

Perseverance Rover Landing Ellipse in Jezero Crater: The white circle near the center of this image of Mars represents the location where NASA’s Perseverance rover landed on Feb. 18, 2021.

But it was also hazardous to land in.

Jezero is 28 miles wide, but within that expanse, there are a lot of potential hazards the rover encounters: hills, rock fields, dunes, the walls of the crater itself, to name just a few. So, if rover would have landed on one of those hazards, it could have been catastrophic to the whole mission.

To tackle with this, Perseverance uses what’s known as ‘Terrain Relative Navigation” (TRN), a technology first used in cruise missiles, to avoid that same failure. In broad terms, TRN consists of two elements: an onboard map of the landing area with elevations and hazards, and a navigation camera. As Perseverance approaches its landing ellipse, the camera compares its real-time images with the onboard map and commands the lander’s rockets to direct the craft away from known hazards.

Overall, the rover’s autonomous landing system is known as ‘landing visions system,’ or LVS.

For Mars 2020, LVS will use the position information to figure out where the rover is relative to safe spots between those hazards. And in one of those safe spots is where the rover will touch down.

This was all about the mission. I will be writing about the THE LANDER VISION SYSTEM FOR MARS 2020 in next blog. Stay Tuned!