Analyzing EVA and Space Time Flight Duration

in the Different Eras of Space Exploration

Erika Yu, Genesis Jaimes, Melody Zeng

Social Sciences

Research Question

How have mission flight durations and EVA activities evolved across different eras of space exploration, and what do these changes reveal about the broader motivations of human space exploration?

Eras of Space Exploration

Eras of Space Exploration

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Space Race (1960–1979)

• Main contenders: U.S. vs. USSR
• Shorter missions focused on just reaching space
• Apollo Moon landings (1969–1972) mark the peak
• Satellites, science labs, and defense payloads during the Cold War

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Shuttle Era (1980–1995)

• Challenger Disaster (1986): Shuttle grounded nearly 3 years
• Reusable spacecrafts, satellite deployment, and international projects

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Eras of Space Exploration

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ISS Era (1996-2005)

• Strong international collaboration
• Shift to long-term habitation (months at a time)
• Surge in missions to assemble and support the ISS
• Columbia Disaster (2003): Shuttle grounded for ~2–3 years, dip in missions

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New Space Era (2006–present)

• U.S. Shuttle retired in 2011: dip in missions
• Rise of commercial spaceflight (SpaceX, Blue Origin, etc.)
• Lunar/Mars missions
• Private-public partnerships

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Beginning Data Analysis...

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Condensing variable labels

Hierarchical Cluster Analysis

Exploratory Data Analysis

Deriving Relationships

Condensing Data Labels

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• Simplifying column names

Profile.Lifetime Statistics.Mission duration

Lifetime_Mission_Duration_Hrs

• Dropping the military column and indicating units

Exploratory Data Analysis

Exploratory Data Analysis

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19 variables, 1270 observations

• Variables range from numeric, to text, to categorical, and even boolean
• Most Astronauts being born in the 1950s
• 39 distinct nationalities represented
• An average mission count of 3 missions

Summary of Data

Hierarchical Cluster Analysis

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Preparing Cluster Analysis

• Creating 7 clusters around����And create a new column in dataframe to indicate the assigned cluster
• Create bins for ranges of years�

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�For each era of space travel

• Creating a subset of the dataframe to specifically look at countries with most space mission:�USA, Russia, Japan, and Canada

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What is Hierarchical Cluster Analysis?

An algorithm that groups data into a tree of nested clusters through a dendogram.

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• Highlights patterns and connections in datasets.
• Visualizes the distant relationships between clusters.

• Clusters 7 and 5 are short missions with little to no EVA.
• Cluster 2 is almost exclusively in orbit on the ISS and has the longest average mission duration.
• Certain vehicles dominate specific clusters: in Cluster 1 it’s Mir, in Cluster 8 it’s Salyut 6, and in Cluster 9 it’s Salyut 7.
• Short missions reflect limited EVA, while long missions cluster around space stations, where single vehicles shaped astronaut experience.

Deriving Relationships

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• Clusters 5 & 7 → short missions, little to no EVA
• Concentrated in 1980–1995
• EVA activity limited (<200 hrs/year)
• 1995: EVA decline despite peak mission count
• Contrast: post-2000 EVA boom (330 hrs/year)
• Cluster 2 → almost entirely ISS missions (2006–2020)
• Longest average mission duration
• Defines ISS era:
• Strong international collaboration
• Shift to long-term habitation
• Surge in missions for station assembly

Works Cited

“A Brief History of Space Exploration: The Aerospace Corporation.” Aerospace Corporation, 1 July 2025, aerospace.org/article/brief-history-space-exploration.

“The History of the Space Race.” Education, education.nationalgeographic.org/resource/history-space-exploration/. Accessed 21 Sept. 2025.

“Https://Www.Nasa.Gov/Wp-Content/Uploads/Static/60counting/NASA: 60 Years & Counting - Human Spaceflight.” NASA, NASA, www.nasa.gov/specials/60counting/spaceflight.html. Accessed 21 Sept. 2025.

“Space Race Timeline.” Royal Museums Greenwich, www.rmg.co.uk/stories/space-astronomy/space-race-timeline. Accessed 21 Sept. 2025.

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