x
Breaking News
More () »

'These clouds are really exciting,' says lead researcher for study into clouds on Mars

9NEWS spoke with the lead researcher of a study looking at how clouds form on Mars.

BOULDER, Colorado — A new study by researchers from the University of Colorado Boulder suggests clouds on Mars are formed by meteoric smoke created after meteors impact the planet's atmosphere. 

Lead researcher Dr. Victoria Hartwick worked with Brian Toon from CU Boulder and Nicholas Heavens of Hampton University on the study. It was recently published in the journal Nature Geoscience.

9NEWS sat down with Dr. Hartwick to learn more about the study and its findings.

(Editor’s note: This interview has been edited for context and clarity.) 

9NEWS: What prompted your research?

Hartwick: When we look at Mars, there are a bunch of clouds really high in the atmosphere between about 30 and 50 kilometers that we just can’t reproduce in any of our global simulations of them. So, we really wondered why are these clouds there and how are they forming?

How long have people been asking that question?

Hartwick: Really, we’ve been curious about it since we started seeing clouds on Mars. Especially when we started seeing the vertical distribution, so where clouds are in the atmosphere. Ever since then, kind of the prevailing view is that clouds are going to form on dust coming from the surface but it’s really hard to get dust to altitudes above 20 or 30 kilometers. So, we needed to find a new source of what they call "ice nuclei," or things for clouds to form on top of.

Where did you start?

Hartwick: The first thing we did was try to look to earth as an example. So, there are regions of the earth’s atmosphere where there is polar summer, it’s really cold, there are very few aerosols and we see clouds there. They’re actually forming on the burnt-up bits of meteor, really small meteoric material. We wondered if a process similar to that was happening on a more global scale on Mars. When we sent the Maven spacecraft to Mars, they started identifying this layer of ionized metals. That says ‘hey, we have meteors impacting the atmosphere, burning up, and then coagulating into smoke.’ These could act as the seeds for cloud formation. 

How did Maven help with your research?

Hartwick: We’ve been looking at this process probably for about two to three years. We were lucky that the Maven spacecraft arrived at Mars and started doing analysis right at the same time as we were interested in this process. So, they were able to give us ground-based truth to support the hypothesis that we had. Through Maven, we knew that these particles were there. Then we could put these in our model and see if they produced the clouds like we imagined.

What did your model reveal?

Hartwick: It was really exciting and pretty surprising! These really, really small particles, and not a large amount of mass, only about like 400 pounds per day of material, could be dispersed so globally and form these clouds all over the surface. This was really exciting.

Where does your research fall into our greater understanding of Mars?

Hartwick: These clouds are really exciting and interesting. In part because what we believe they could do earlier in the planet's history. So, there’s this mystery about why Mars has geologic features that look like there was running water for a long period of history. It’s really hard to get it warm and wet. One hypothesis is that these really high altitude clouds could radiatively warm the surface sort of like a greenhouse effect. These clouds would form exactly in the area that we’d expect if we want them to exist. The flux of this meteoric material would have been higher early in the solar system. So, this could be a really important first step in warming Mars early in its history. So, that’s pretty exciting!

What do you hope comes next in the study of Mars?

Hartwick: I’d be really interested to see what we can learn about early Mars. So, what its climate was like four billion years ago. The Maven satellite is helping us constrain how much atmosphere escaped over time which can tell us the atmospheric conditions earlier in its development. From that, we can learn something about whether it was warm and wet or cold and dry and even what the habitability of early Mars was.

What drew you to look at Mars in the first place?

Hartwick: It’s a really interesting planet, not just because it’s a climate system that’s different than our own but there is still potential that we could find life deep in the subsurface because we’re learning more and more about the water budget on Mars. Even though it's just like a desert planet and it looks dead, it's still a really interesting playground to learn about planetary climate and learn about our own solar system and what might be out there in other solar systems. 

Do you think we'll be traveling there anytime soon?

Hartwick: I mean, I really hope that we get there in the 2030s like we’re proposing!

Why did you choose the University of Colorado Boulder for graduate school?

Hartwick: I really wanted to be at a school that emphasized atmospheric modeling of planets outside of earth. There’s really only a few places and CU Boulder is one of them. So, I had the good fortune to work with Brian Toon at the university. He’s done some amazing work looking not only at Mars now but Mars in the past and also other planets in our solar system and moons like Titan. 

CU is almost like an epicenter of Mars research. We have this really amazing mission that is happening and based at the university which is really looking at atmospheric escape. We’re also using some of the most advanced general circulation models to study the climate of Mars. So, this is really an exciting place to start looking at different planetary atmospheres and how we can study them.

What will you study next?

Hartwick: I am actually going to be looking at Mars-like exoplanets, planets outside of our solar system which are sort of like Mars in that they’re arid and kind of desert-like. We kind of jokingly call them dune-worlds. We’re interested in how the climate is impacted by limited amounts of water. So, we hear a lot about the greenhouse effect and the runaway greenhouse on a planet like Venus but what happens if the amount of water is so low that you can’t enter that regime. That’s what I’ll be studying out in California.

Before You Leave, Check This Out