6 July 2009
Student Questions about Mars Exploration
Posted by Ryan Anderson
A few months ago, a class of 6th graders at JFK Middle School in Hudson, MA contacted the astronomy department at Cornell. They were doing an egg-drop project, modeled after the Mars rovers, and their teacher had them each write questions to Steve Squyres about the rover mission. Steve was out of town (and is always extremely busy), but he suggested that many of the questions could be answered by grad students!
So, I selected a handful of questions, and I’m posting the answers here because there’s a good chance that other people have similar questions, and this is a good way to make the responses public.
Did you always want to be a scientist?
Yes. Even when I was in kindergarten, when people asked me what I wanted to be when I grew up, I said: “A [locomotive] engineer, and a scientist on weekends.” I lost interest in trains, but not in science.
What first got you into space and Mars? What interested you in becoming a grad student in Astronomy?
I always thought space was pretty cool, but in high school I took an elective course in astronomy. We had an assignment where each group was given an object in the solar system and had to design a mission to send humans there. My group was assigned Europa, and as I was reading about its icy crust and the possibility of a liquid ocean beneath the surface and trying to figure out how to send people there, I had the realization: “There are people who do stuff like this for a living!” So that got me started. And then my teacher for that class told me to take a look at books by Carl Sagan like Cosmos and Contact. Once I read those (and everything else by Sagan that I could get my hands on) I was totally hooked.
How did you get where you are today?
In undergrad I wasn’t sure at first whether I wanted to do English or astronomy. I’ve always been better with words than with math. But I decided that if I want to I can always write if I study astronomy, but I can’t do science if I study English. So I ended up double majoring in Astrophysics and Physics in undergrad. That gave me a good foundation, and also gave me the opportunity to try different summer research projects. I studied a flare on a nearby star, dust clouds in the constellation Orion, buried impact basins on Mars, and a new type of instrument for space exploration. By the end of undergrad I realized that I didn’t want to do just physics, I wanted to study planets, and particularly planetary surfaces. So I applied to graduate schools in planetary science and decided on Cornell because it has several people involved in studying the surface of Mars.
How did you get involved in Mars exploration?
Once I was at Cornell, I talked to various people doing research that interested me (mostly Mars stuff), and started working for Jim Bell, the leader of the pancam color cameras on the rovers. He is involved in lots of other Mars missions in addition to the rovers, so over the last few years I’ve gotten a good taste of orbital, rover and laboratory work related to Mars.
What is the worst part of your years of being a grad student?
Oooh, good question! Before I answer, I want to make clear that there are good things about grad school too. I mean, I get paid to look at landing sites on Mars and shoot rocks with lasers! And I can work any hours I choose (so long as I get my work done). And you get to travel to interesting places and talk to interesting people about interesting questions. Etc. So now that that disclaimer is out of the way, the bad stuff:
The worst part would probably be self-doubt. In graduate school, you are trying to contribute to scientific knowledge, but everyone else who studies the topic has been doing it for longer than you (some of them for longer than you’ve been alive!). So you have to learn everything as you go: not just the facts, but how to pose good scientific questions, how to apply for funding, how to use the data, etc. It’s easy to feel overwhelmed and discouraged. Some people go so far as to feel like they don’t belong in a field with so many people that they think are smarter than them. This is called the “Impostor Syndrome“. But a good adviser, and getting to know others in the field is very helpful, as is talking to other grad students.
Also, academia tends to make it seem like you should always be working, and so there is some guilt whenever you do anything else:
When you started on Mars exploration did you have any big questions?
Whenever people ask what the big questions I’m interested in are, I have a hard time because my interests are pretty broad. Generally, all of the big questions about Mars interest me. I want to know what Mars used to be like, and how and why it changed to the way it is now. And, of course, whether there was ever life on Mars.
What is the most fascinating fact (s) that you have found?
I’m going to interpret the “you” in this question as aiming at all of Mars scientists, because so far I haven’t found anything especially groundbreaking.
I think it is very interesting that we are seeing evidence from orbit for minerals that formed in life-friendly waters on Mars, but that the current planet is extremely dry and cold and that most of the evidence from the Rovers suggests that the water was salty acid that wasn’t very good for life.
Were you surprised to find out there was once water on Mars?
Not particularly. There is a joke among Mars scientists that water on Mars is “discovered” about every two years. We’ve known that there was water for a long time, but it seems like everyone else forgets after a couple of years until we find new evidence and it is reported as “the discovery of water on Mars”.
How much longer do you think it will be before humans can live on Mars?
If we wanted to go, we could go in 5-10 years. We would just have to build a big enough rocket. The problem is that it would be very expensive, and it is hard to convince the president and congress to do something so expensive when it probably won’t have any tangible benefits (it won’t save lives or make money, although it would make lots of jobs for the people involved in building the rockets). I think in reality it will be more like 30-40 years before we send humans to Mars. Maybe it will be sooner, but other than Apollo, everything else in space exploration tends to take longer than expected.
How did you get in the lander business?
I worked hard in college to get good grades in astronomy and physics, and did summer research internships, and then I applied to a bunch of graduate schools. I was lucky enough to get into Cornell, where they were already running the rovers, so when I got here, I started to work with Jim Bell and he helped to get me involved with the current rovers, Spirit and Opportunity, and the upcoming Mars Science Laboratory mission that will launch in 2011, named Curiosity.
Have you worked on other planets other than Mars?
No, I haven’t. My non-Mars research was on infrared pictures of star forming regions, and on a bright flare on the nearby Barnard’s Star.
If you had unlimited resources, would your mission to Mars have been different?
With unlimited resources, I would send people! People are a lot smarter, faster, agile, and creative than our robots. In one day I could walk as far as either of the rovers has gone in five years. If I were collecting samples and making measurements, maybe it would take weeks.
Do they pick people to be involved in Mars exploration or do you just
go there and sign up?
Generally, you go to graduate school as either an engineer or a scientist, and you get involved by meeting with and working for people who are already involved.
How can you slow down the landing?
The main ways that we use to slow down the landing are heat shields, parachutes and rockets. The heat shield protects the spacecraft as it enters the atmosphere: friction with the air slows the spacecraft down and heats the shield to thousands of degrees. Next parachutes come out, causing even more air resistance to slow the lander down. Finally, rockets are used at the end to bring the spacecraft to a stop.
One more question related to Mars landing. I saw animation of Phoenix landing and it looks like it wasn’t very stable in motion when parachutes come out. How did they manage to do strictly vertical landing on rockets at the end in this case? I’d expect lander not to be horizontally aligned just before rockets are fired. Thank you!
I don’t know all the details since I’m not an engineer, but I think that by the time the rockets fire, it is getting close enough to vertical that its radar can detect the direction of the ground. Then once it is flying on the rockets, they all adjust their thrust “on-the-fly” to keep the ground directly below the lander and to approach it slowly enough to be safe.
Landing on retro-rockets was the way things were originally landed on other planets, so it is a very well-proven technology.
i want further information about the mars how can i get it .and i also want to be a scientist what should i do and furhter that if the a little part of that planet become ready for agriculture it is not possible but if we try a little it is a possible then i think then it is not so for to live on mars thanks
fadu!it helped me alot