Why Sunita Williams sees 16 sunrises and sunsets just in one day? it’s almost every 45 minutes due to…

For astronauts aboard the International Space Station (ISS), the cycle of sunrise and sunset is far from ordinary. Instead of experiencing these phenomena just once each day, they witness them 16 times daily. NASA astronaut Sunita Williams, who is currently on the ISS, has often reflected on this extraordinary aspect of life in space.

Sunita Williams Experience 16 Sunrises and Sunsets

In 2013, while being felicitated at the University of Gujarat in the presence of then Chief Minister Narendra Modi, Sunita Williams shared her thoughts on this surreal experience. “Because I had wanted to go to space and worked hard for it, I was lucky to see 16 sunrises and 16 sunsets in a day in a fast-moving space shuttle,” the astronaut said.

Currently on an extended mission due to delays in the Boeing Starliner spacecraft’s return schedule, Ms. Williams will remain in orbit until February 2025. Alongside fellow astronaut Butch Wilmore, she is using this additional time to contribute to essential research and embrace the unique opportunities space offers, including the breathtaking sight of multiple sunrises and sunsets each day.

The Science Behind It

The ISS orbits Earth at a staggering speed of approximately 28,000 km per hour, completing one full orbit every 90 minutes. This rapid movement allows astronauts to move from the dark side of Earth to the sunlit side and back again, witnessing a sunrise or sunset roughly every 45 minutes.

Day-Night Cycle in Space

Unlike Earth, where a day consists of roughly 12 hours of light and darkness, astronauts aboard the ISS experience a continuous cycle of 45 minutes of daylight followed by 45 minutes of night, 16 times within a single Earth day. This rapid alternation creates a unique rhythm of day and night, making timekeeping in space vastly different from that on Earth.

How Astronauts Mark Time in Space

In the absence of natural daylight patterns, astronauts rely on Coordinated Universal Time (UTC) to structure their schedules. The day aboard the ISS is meticulously planned, with work, meals, and rest scheduled down to five-minute intervals. This regimented routine is vital for maintaining physical and mental well-being in an environment so removed from Earth’s natural cycles.

To ensure synchronization with Earth-based teams and precise navigation for future deep-space missions, astronauts use highly accurate atomic clocks. These tools not only help keep them on track but are also critical for mission success beyond Earth’s orbit.