An as-told-to essay is based on a conversation with a NASA Astronaut. It has been edited to make it clearer.

Prior to working at NASA, I was a physics professor at West Point and graduated with a master's degree in applied physics. A senior Army Astronaut came to an Army Space Operations conference looking to find someone to work in the Astronaut Office as part of an agreement to broaden the experience base of space operations officers in the Army.

I became a NASA Astronaut in 2011. I returned to Earth after 355 days in space. I am the American who has spent the most days off of our planet.

There was a lot of uncertainty about the duration of the spaceflight. They initially told me that it could last up to 355 days, but that didn't happen until halfway through the flight. My wife and I were going to be away for a long time. My previous spaceflight had lasted about six months, so I thought this was a unique challenge.

It was a smooth journey up to the International Space Station. When you watch a launch from the ground, there is a lot of light and noise, but you pass the speed of sound so quickly that you don't notice anything. The pumps were making noise to push the fuel out.

When you first get to the ISS, it takes some time to adapt to the fact that the room you're in is constantly falling toward Earth 

(left to right) Vande Hei with Shane Kimbrough, Akihiko Hoshide, and Megan McArthur, pose with chile peppers grown in space for the first time aboard the International Space Station.
From left to right: Vande Hei with Shane Kimbrough, Akihiko Hoshide, and Megan McArthur, pose with chile peppers grown in space for the first time aboard the International Space Station.
NASA

There are a lot of things that you don't need to think about. You have to relearn how to do them when you are in space. If you don't pay attention to how to get to the bathroom, you could end up in a mess. If you don't anchor your feet to the floor, you will end up floating to the ceiling when you sit down to use your laptop.

You can go days without seeing one of your roommates if you live in a six-bedroom house. If there was to be an emergency, the modules can be isolated and closed off. The Russians added two new modules to the International Space Station on this latest flight.

Most weekdays start between 6 and 7 a.m. GMT

Vande Hei uses an electric razor with a vacuum attached that collects the hair he's cutting off fellow NASA astronaut Thomas Marshburn.
Vande Hei uses an electric razor with a vacuum attached that collects the hair he's cutting off fellow NASA astronaut Thomas Marshburn.
NASA

We are going to have breakfast before the conference starts. We keep an eye on the ground control teams in Japan, Russia, Europe, and the US. During the day, you have one hour for lunch and then two and a half hours for exercise, with a treadmill and a stationary bike. It's important to keep our strength and bone density at a healthy level by exercising. Most of the time, we complete tasks set out by the teams on Earth.

There is a row of astronauts' names and a horizontal line that moves slowly throughout the day. It helps us stay on track by guiding us on what to work on. It's my favorite part when I get to work with the other astronauts. You can help someone else if you get ahead on your own.

During this latest flight, we helped conduct hundreds of experiments whether they happened behind the panels or on ourselves 

Vande Hei conducts operations for the Plant Habitat-5 space-agriculture experiment that is studying cotton genetics.
Vande Hei conducts operations for the Plant Habitat-5 space-agriculture experiment that is studying cotton genetics.
NASA

My role as a laboratory technician is more important than my role as a scientist because I facilitate the success of the experiments more than taking down data, analyzing it, or writing the reports.

There aren't many "specialists" within the team. Being a generalist is important because sometimes the plan will change while we are up there. You need people who can do a lot of different things.

Other than meetings, experiments, and maintenance around the station, spacewalks take up the rest of the day

Vande Hei during a spacewalk to service components on the Canadarm2 robotic arm.
Vande Hei during a spacewalk to service components on the Canadarm2 robotic arm.
NASA

The solar array on the outside of the International Space Station has been upgraded. It's important that we have consistent power because the space station is solar powered. I have done spacewalks in the past, even though I didn't go out on a spacewalk myself.

Being in space is like a long fall toward the planet, with you and everything around you falling at the same rate. Being in space is like that.

The workday lasts until about 7:30 p.m. when we finish another meeting.

On the weekends, we usually had time off, other than about 3 hours of house cleaning — I love to tell school kids that

On Fridays and Saturdays, we had an entire crew dinner, and then on Sundays, we all watched a movie together. One of the choices I made was "Yesterday" with all the Beatles songs.

Vande Hei peers at the Earth below from inside the seven-windowed cupola, the International Space Station's window to the world.
Vande Hei peers at the Earth below from inside the seven-windowed cupola, the International Space Station's window to the world.
NASA

I talked to my wife and kids every day during the flight. I have to get to know a lot of my family members. When you call someone and they're blown away by the fact that you're talking to them from outer space, it's pretty cool. I used to sit at the window and meditate every day.

I think it's a unique experience.