Hours Duration Calculator
Use our Hours Duration Calculator to see how long Apollo 13’s fateful journey lasted — down to the very hour.
Try It Yourself
You can use the calculator above not just for Apollo 13, but for any event in history.
Example inputs:
- Start: April 11, 1970, 14:13
- End: April 17, 1970, 13:07
Result → 142.9 hours
Or try comparing:
- Time between Apollo 11 (1969) and Apollo 13 (1970)
- Duration of modern ISS missions lasting over 6 months (≈ 4,000+ hours)
This simple tool makes it easy to understand history through the dimension of time.
The Apollo 13 Story: 87 Hours of Tension and Triumph
Apollo 13 was meant to be NASA’s third crewed mission to land on the Moon. Instead, it became one of the most dramatic rescue missions in history.
- Launch: April 11, 1970, at 2:13 PM EST
- Explosion: April 13, 1970 — “Houston, we’ve had a problem.”
- Splashdown: April 17, 1970, at 1:07 PM EST
That’s a total of 142 hours and 54 minutes (about 5 days, 22 hours, and 54 minutes) spent in space — every one of them filled with uncertainty, ingenuity, and courage.
The Science Behind the Survival
After an oxygen tank exploded, Apollo 13’s mission shifted from “go to the Moon” to “get home alive.”
The astronauts — Jim Lovell, Jack Swigert, and Fred Haise — were forced to shut down their main spacecraft and retreat into the Lunar Module, designed to support two men for only two days.
NASA’s engineers worked tirelessly around the clock to calculate oxygen levels, power usage, and trajectory — literally measuring their survival in hours.
Time: The Real Enemy of Apollo 13
In those 142 hours, time became everything:
- Every second of oxygen mattered.
- Every hour of battery life was critical.
- Every course correction was timed to perfection.
The crew had to navigate by hand, slingshot around the Moon, and return to Earth with only the most essential systems active.
Your Hours Duration Calculator above lets you input those exact timestamps — so you can experience how long those intense days truly lasted.
Why the Apollo 13 Mission Still Inspires Us
The phrase “Failure is not an option” became a symbol of human resilience.
From that 1970 crisis, NASA learned how to manage emergencies, conserve energy, and rely on teamwork under unimaginable pressure.
Today, those same principles guide every space mission — including the Artemis program, aiming to return humans to the Moon.
Fun Facts: Apollo 13 and the Clock
- The Lunar Module’s batteries were designed for 45 hours but lasted nearly 90.
- The astronauts slept less than 6 hours a day during the mission.
- The reentry window was only a few minutes wide — if missed, they could have bounced off Earth’s atmosphere.
- Time literally decided whether Apollo 13 would succeed or fail.
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Final Thoughts
Apollo 13 wasn’t just a spaceflight — it was a race against time.
When you calculate those 142 hours, you’re not just measuring duration — you’re measuring human endurance, courage, and problem-solving at its finest.
Time can be an obstacle, but as Apollo 13 proved — it can also be a story of survival.