Famous astronaut Scott Kelly is about to come home - here are 8 epic numbers about his record-breaking time in space

713 photos posted to Instagram — that's on average two posts per day.

915,000 Twitter followers, which he interacted with more than 2,000 times. Here's his Twitter profile picture:

5,440 orbits around Earth, while traveling at over 17,000 mph.

10,944 sunrises and sunsets — the same amount the average human experiences over the course of about 30 years.

648 miles — on the ISS treadmill. To minimize the loss of muscle and bone mass in space, astronauts exercise a lot. Kelly logged more than 700 hours of exercise.

193 gallons of recycled sweat and urine. Water is heavy and expensive to transport to space. Instead of lugging a bunch of fresh H20 with them, astronauts recycle their urine and sweat to drink. Kelly downed close to 200 gallons' worth.

400 science experiments conducted.

143,846,525 miles of total travel in the ISS. That's about the same distance as a one-way trip to Mars, according to The New York Times.