General, Research, Technology

Great interview with the creator of the Perseverance rover. Bacteria, iPhone and the search for life

The interesting time we live in becomeseven more interesting. Something like this can be said about what is happening in the world now. Rockets fly higher, research vehicles fly farther, and more and more sophisticated and heavy rovers are delivered to Mars. A big event happened yesterday when the Perseverance spacecraft landed on the Red Planet in several stages. Only from the moment the rocket was launched from Earth to this moment, about six months had passed, and how much more it took to develop the equipment and prepare the mission ... For this event, ExtremeTech prepared a long interview with Adam Stelzner, chief engineer of the Mars 2020 project. He was not only involved in preparing the flight and rover, but also a complex system for returning Martian soil samples back to Earth for further study. We decided that this interview was too interesting to ignore, and we want to cite the most important points from it.

Mars rover Perseverance.

Content

  • 1 Has the rover landed on Mars
  • 2 How the Perseverance rover works
    • 2.1 Perseverance and Curiosity
    • 2.2 Where did NASA's rover land
    • 2.3 Why on Earth samples of Martian soil
    • 2.4 How to avoid contamination of Martian soil
    • 2.5 When will the Martian soil be brought to Earth
    • 2.6 Was there life on Mars
    • 2.7 What Mars smells like
    • 2.8 When Mars is Colonized
    • 2.9 How planets will be explored
  • 3 Operation of the Perseverance rover

Has rover landed on Mars

In a separate article, our Ramis Ganiev has alreadytalked about how the Perseverance spacecraft was delivered to the surface of Mars. In short, everything went well on the whole, and the rover has already sent photos of the planet.

Naturally, there is still a lot of work and collected materials ahead, but it is already clear that the mission has become the most ambitious ever to explore Mars... In addition to the rover itself, the surface willstudy a small helicopter that is specially designed to fly in that atmosphere. It is heavily discharged and corresponds to the density of the Earth's atmosphere at an altitude of about 35 kilometers.

Adam Stelzner.

ExtremeTech: Were there any ideas that you simply could not implement due to lack of time or money?

Adam Stelzner: I think yes.

ExtremeTech: Did you get everything you wanted?

Adam Stelzner: Rarely does someone say: "Did you get everything you wanted?" That's why I need time to say yes, because I say, I think yes.

The Perseverance rover has landed on Mars. How it was?

Where NASA's rover landed

ExtremeTech: What is the geological significance of Jezero Crater, where Perseverance landed?

Adam Stelzner: Scientists decided to go to Jezero Crater, because once there was a lake in this place, and right where we land there was a delta.

Fan-shaped delta structure occurs due to the fact that the river flows into a large body of water and the water slows down. When the water slows down, the average speed in the stream decreases and it can no longer carry these particles in the stream.

This is how the place where the rover sat down could have looked like this.

The settled particles are incredibly good at preservingevidence of life that dwelt there, as they add a protective layer of geological material. Deltaic deposits are the best place to look for signs of ancient life.

Why on Earth are samples of Martian soil

ExtremeTech: Let's talk about the sample return system.Why waste energy returning samples to Earth? What can you do with a sample of Martian soil here on Earth that can't be done with a Mars rover on Mars?

Adam Stelzner: The answer to this is quite simple - all thatwant to. The problem is that there is no way to do such detailed research on Mars. Imagine taking something the size of a room, including most of the equipment, and making a miniature version hardened for space travel, attaching it to a rover, and sending it to Mars. You take measurements and think: "Yes, it looks like there is organics, but I would like to do other research”. As a result, you need to come up with another mission and send it to Mars again and so over and over again. This cycle lasts about 10 years.

To drive on Mars you need special wheels.

If you bring samples from Mars to Earth, you havethere will be all the equipment of the earth, all the scientists of the earth, all the ingenuity inherent in the entire globe, which can be used in the study of samples.

What will the rovers of the future look like?

How to avoid contamination of Martian soil

ExtremeTech: It looks like if you are returning all these samples and are going to do all these tests, you want to be sure that you don't accidentally analyze any pieces of the Earth.

Adam Stelzner: Right.

ExtremeTech: How can you be sure? You are building these things in the atmosphere of the Earth. How to make sure nothing gets into sample containers?

Adam Stelzner: This is a huge problem. We have created the cleanest equipmentthat has ever been in space.I designed a sampling system and invented cleaning protocols. It was a huge effort. For example, sample vials are made of titanium but have a titanium nitride surface. The titanium sample tube is exposed to a low pressure nitrogen gas plasma in a high energy environment. This high-energy nitrogen plasma penetrates the titanium surface and creates titanium nitride, which is a refractory and incredibly inert material. It is more passive than gold. This passivity means that the particles trapped inside will not be able to stay there. In a way, it looks like Super Teflon.

You can't just collect the soil in a bag. We need special containers.

We then take this ultra-clean passive system sampling tube and place it behind the liquid mechanical particle barrier. It is a specially designed barrier that prevents particles larger than 0.3 microns from entering the volume, in which the sample tubes are sealed.Then, when they are in it, we put them in a heat chamber for several hundred hours and clean everything inside this tube. As a result, we get sterile containers individually wrapped.

When will the Martian soil be brought to Earth

ExtremeTech: I think you need two more missions to get these samples back to Earth. Correctly?

Adam Stelzner: Right.

ExtremeTech: When do you think you can bring them back to Earth?

Adam Stelzner: After about 10 years, even after 10-12 years.

Mars rover InSight has stopped drilling a well on Mars. What happened?

Was there life on Mars

ExtremeTech: If you find traces of life on Mars when you return these samples, what evidence will convince scientists that something was alive in Jezero Crater three billion years ago?

Adam Stelzner: Signs of ancient life can take many forms.To make a convincing case, you probably need to agree on several of these forms of evidence. For example, you would look at morphological shapes that look like microstructures. Then you have to see if these shapes were made from what I think scientists have called carrageenan, which is essentially the carbon residue of life. You would use multiple lines of evidence anyway.

I don't even know whether to admire his appearance or not. But it is technically perfect and has everything you need.

You would look at that place in the geologicalfield where these things were located, and you would see that it was connected, for example, with the lake shore in the past. You would use sets of evidence that agree and support the claim of ancient life as you see it. Only together all these things together say that there really was life on Mars. This was the ancient bottom of the lake, and there must have been algae that formed at the edge of the lake.

What does Mars smell like?

ExtremeTech: What does Mars smell like? Obviously, you didn't go there to sniff it, but are you guessing?

Adam Stelzner: Mars smells like your grandparents' suitcase that hasn't been opened in decades.

ExtremeTech: I like it. Why?

Adam Stelzner: Mars is dry, old and dusty.

When Mars is Colonized

ExtremeTech: How far do you think we are from being able to colonize Mars?

Adam Stelzner: I hope to be infinitely far from being able to colonize Mars.

ExtremeTech: Don't you think Mars is where we should live?

Adam Stelzner: Not.During the evolution of the Earth, the environment at times became very bad. In particular, about 65 million years ago, when an asteroid crashed into the Yucatan Peninsula region and killed all the dinosaurs, severely polluting the atmosphere. He killed many plants and 90 percent of living organisms. In the midst of those events, the environment on Earth was still infinitely more habitable than what we could ever create on Mars. I think so.

We evolved to have one terrestrialthe gravity that keeps my cerebrospinal fluid at the right pressure. Our organisms are adapted for existence on Earth. If we cannot move as we are used to, we will grow old very quickly. The fibers of our bones grow in the directions of the basic stress state of the skeleton, determined by how it interacts with the Earth. Departing from these conditions is very wrong for us.

A helicopter on Mars is already a historic event.

How planets will be explored

ExtremeTech: What do you think will be the next game-changing technology for planet exploration?

Adam Stelzner: I think the next revolutionary technologyfor planetary exploration, which may not seem very good, it will be the use of commercial off-the-shelf consumer electronics. Here is an illustrative, albeit absurd example. Imagine 10 iPhones in a box. They are not radiation hardened, but they work. Processors are constantly performing tasks. Some of them may break, but others will work. We do this all the time with some things, for example, the Boeing 777 has three computers, and they back up each other, so if one computer fails, the plane will fly further.

The processor we have Perseverance on is the same as the Curiosity processor. He is the same as was in my Beige Box G4 Macintosh in 1999when I got my Ph.D.When creating a computer for Perseverance, a person manually solders wires to wires. It is heavy, expensive equipment, built 25 years ago. 10 times more, 100 times more than the current ones. I haven't done any math on my iPhone lately, but it has more processing power. [The authors of the interview checked and found that the current iPhone is about 15-20 times faster than the processor in Perseverance.]

The modern iPhone has 15-20 times more computing powerthan the host computer of the Perseverance rover

An interplanetary spacecraft is standing aboutbillion dollars. When launch services drop to around $ 100 million, the launch will no longer be considered expensive. Now you probably ask how can i reduce the price of a spaceship? One of the important points that couldbe, is how we control, how we program, how we drive a vehicle. The use of modern technologies and their application in space exploration can allow us to reduce the cost of missions and further increase the value of our robotic space exploration.

This is how the rover was prepared to be sent to Mars.

The work of the Perseverance rover

The interview provided answers to many questions andmade it possible to better understand how the apparatus was built, and to think about such things that simply did not come to mind before. For example, soil contamination with bacteria from the Earth. It turns out that this was thought out too. Could it be otherwise, when such an important and expensive mission was being prepared for such a long time? At the same time, to obtain samples, you will have to launch another one, and contamination of containers could put an end to both.

We will still prepare more than one material on this topic, but for now you can once again familiarize yourself with how the device landed on the surface of Mars.