# Gemini 4

> second crewed space flight in NASA's Project Gemini

**Wikidata**: [Q747769](https://www.wikidata.org/wiki/Q747769)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Gemini_4)  
**Source**: https://4ort.xyz/entity/gemini-4

## Summary
Gemini 4 was the second crewed mission of NASA's Project Gemini, launched on June 3, 1965. It featured the first American spacewalk by astronaut Ed White and completed 62 orbits of Earth over four days.

## Key Facts
- Launched on June 3, 1965, from Cape Canaveral Launch Complex 19
- Landed on June 7, 1965, in the Atlantic Ocean, recovered by USS Wasp
- Crew consisted of James McDivitt (commander) and Ed White (pilot)
- First American spacewalk conducted by Ed White during the mission
- Completed 62 orbits with an orbital period of 88.94 minutes
- Spacecraft mass was 3,570 kilograms at launch
- Operated in low Earth orbit with an apoapsis of 282.1 km and periapsis of 162.3 km
- Part of NASA's Project Gemini, which bridged Mercury and Apollo programs
- Used Titan II GLV as launch vehicle
- Mission duration was 5,876 minutes (97 hours 56 minutes)

## FAQs
### Q: What was the primary achievement of Gemini 4?
A: Gemini 4's primary achievement was conducting the first American spacewalk, performed by astronaut Ed White on June 3, 1965. This extravehicular activity (EVA) lasted approximately 23 minutes and demonstrated the feasibility of working outside a spacecraft in microgravity.

### Q: Who were the astronauts on Gemini 4?
A: The Gemini 4 crew consisted of James McDivitt as spacecraft commander and Ed White as spacecraft pilot. Both were from the second group of NASA astronauts selected in 1962. Frank Borman and Jim Lovell served as backup crew members.

### Q: How long did Gemini 4 stay in space?
A: Gemini 4 remained in space for 4 days, 1 hour, and 56 minutes, completing 62 orbits around Earth. This duration was significant as it demonstrated NASA's ability to sustain human spaceflight for extended periods, a critical capability needed for future lunar missions.

## Why It Matters
Gemini 4 represented a pivotal moment in the Space Race and NASA's journey to the Moon. The mission's successful execution of America's first spacewalk proved that astronauts could work outside their spacecraft, a capability essential for lunar surface operations and satellite maintenance. This achievement came at a critical time when the Soviet Union had already conducted the first human spacewalk during Voskhod 2 in March 1965. By demonstrating this capability, Gemini 4 helped restore American prestige in space exploration and provided crucial data on EVA techniques, spacesuit design, and astronaut mobility in microgravity. The mission also validated longer-duration spaceflight, showing that humans could function effectively in space for the extended periods required for lunar missions. These technological and operational advances directly contributed to the success of the Apollo program, which would land humans on the Moon just four years later.

## Notable For
- First American spacewalk, conducted by Ed White on June 3, 1965
- Longest American spaceflight at the time (4 days)
- Demonstrated extended-duration spaceflight capabilities needed for lunar missions
- First use of digital computers for real-time flight control in a U.S. spacecraft
- Featured the first use of fuel cells for electrical power in a crewed spacecraft

## Body
### Mission Overview
Gemini 4 was the second crewed mission of Project Gemini and the tenth crewed American spaceflight. Launched on June 3, 1965, at 15:15:59 UTC from Cape Canaveral Launch Complex 19, the mission carried astronauts James McDivitt and Ed White into low Earth orbit. The primary objectives included testing the performance of the Gemini spacecraft during extended flight, evaluating the effects of prolonged weightlessness on the crew, and demonstrating extravehicular activity capabilities.

### The Historic Spacewalk
The most significant achievement of Gemini 4 was the first American spacewalk, conducted by Ed White on June 3, 1965. White exited the spacecraft at 19:45 UTC, becoming the second human to perform an EVA after Soviet cosmonaut Alexei Leonov. Using a Hand-Held Maneuvering Unit that expelled pressurized oxygen, White maneuvered around the spacecraft for approximately 23 minutes. The spacewalk was terminated after Mission Control expressed concerns about White's extended time outside the vehicle and the approaching night pass.

### Technical Specifications
The Gemini spacecraft used for this mission had a launch mass of 3,570 kilograms and was launched by a Titan II GLV rocket. The spacecraft operated in a low Earth orbit with an inclination of 32.53 degrees, reaching an apoapsis of 282.1 kilometers and a periapsis of 162.3 kilometers. The mission completed 62 orbits with an orbital period of 88.94 minutes. Power was provided by fuel cells, marking their first operational use in a crewed spacecraft.

### Crew and Operations
James McDivitt served as spacecraft commander, responsible for overall mission operations and spacecraft systems, while Ed White functioned as pilot, assisting with navigation and conducting the historic spacewalk. The crew followed a rigorous schedule during their four days in space, conducting experiments, testing spacecraft systems, and preparing for the EVA. The mission demonstrated that astronauts could function effectively during extended spaceflight, with both crew members reporting no significant physiological issues from the prolonged weightlessness.

### Legacy and Impact
Gemini 4's successful execution of America's first spacewalk and demonstration of extended-duration spaceflight capabilities provided NASA with critical experience needed for the Apollo lunar missions. The mission validated EVA techniques, spacesuit designs, and spacecraft systems that would be essential for future operations. The data gathered on human performance during prolonged weightlessness helped inform medical protocols for longer missions. Additionally, the mission's success boosted American confidence in the space program during a period of intense competition with the Soviet Union, helping to maintain public and political support for the ambitious goal of landing humans on the Moon before the end of the decade.

## References

1. Jonathan's Space Report
2. [Source](http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1965-043A)
3. Freebase Data Dumps. 2013