(CNN) Every 90 minutes, an American woman named Peggy Whitson circles the earth. As she does so, 250 miles above the ground aboard the International Space Station, traveling at a speed of 17,500 miles an hour, she grows and harvests her own cabbage, calls her husband and commands a crew of three. As of April, she has spent more days in space cumulatively than any American astronaut, ever.
On Monday, Peggy's 541st day in space, this pioneering NASA astronaut spoke to CNN live on Facebook about how it feels to be a record breaker, her advice for any budding astronauts and what it's like to live in zero gravity.
On how it feels to have spent more time in space than any other American astronaut:
It's actually a really huge honor to represent all of NASA, because without all the people and the team working together to make this happen it isn't possible for any one person to hold this record. So it feels very special to represent the NASA team that makes space flight possible.
On her personal advice for any future astronauts:
Any field in math, science, or engineering is an important field to contribute to space flight and space exploration of any kind, and so I would encourage you to pick one of those fields that really drives you, that really stimulates you to do better and to learn more and really go after it and pursue it and I think you will become anything that you can dream about. I certainly have, and I feel that it's possible for anyone who works hard and puts a lot of effort into it.
On how she prepares for live in zero gravity:
Life in zero gravity is hard to simulate. We practice on the ground what we call "the day in the life" simulations, but it's just practicing some of the tests. It can't prepare you for the fact that all of your tools float if you don't pay attention to where they are! If you don't Velcro things down, they're gonna float away. It's also just incredibly disorienting to be able to work in any orientation! I can work on the ceiling or I can work on the walls and be equally comfortable in any of those orientations, but it does cost you, in the sense that you have to keep track of your tools and all the things around you.
On her favorite space discoveries to date
I think probably the discoveries made by Hubble Space Telescope have been very dramatic, very amazing. I can't discount some of the discoveries made on Mars. I also feel that the International Space Station is a critical stepping zone and the research we're doing here is going to help take us to those distant destinations and further explore space. There's nothing like our technology development, where we're working on a closed-loop life support system trying to get that perfected. We're looking at bone cells, bone growth, what exercise requirements are necessary to minimize those losses, you know, are there drugs that we can take that would minimize those losses? There's lots of really interesting research.
On gardening ... in space:
We're growing cabbage now, it's called Chinese cabbage. It's more like a lettuce. Even though we're doing scientific research on it, we get to harvest it to eat every once in awhile and that's a lot of fun for us as well.
On checking in with loved ones on Earth:
Here, in low earth orbit, we're going around the earth, so we can actually use an internet protocol phone because we have the appropriate satellites that can get those bandwidths. I talk to my husband pretty much every day. I talk to my parents and my family probably once a week at least, and friends all the time too. So, communication now is not difficult. I think for those future exploration missions, where we're not gonna have that immediate communications capability because we're going to be going such distances that it's going to take maybe 20 minutes for a message to get one way to Mars, so it's going to be a dramatic change. Right now I think we've got it easy by comparison.
On the one food she craves the most while in space:
We get to eat the lettuce, but that's only a few leaves, maybe a couple of leaves each every few weeks or so when we're growing it. So that's the one thing I miss the most! A really fresh salad with lots of different vegetables on it.