On Jan. 28, 1986, seven astronauts perished when Space Shuttle Challenger exploded 73 seconds after take-off, including Christa McAuliffe of New Hampshire High School who became NASA’s inaugural civilian astronaut.
An inedible piece of foam insulation fell from the booster during launch and struck the spacecraft’s wing, allowing hot exhaust gases to escape and leading to its explosion.
What Caused the Explosion?
Spacecraft are vehicles designed to leave Earth’s atmosphere and travel through space. There are various kinds of spacecraft, from satellites that orbit Earth to robots that explore other planets; most spacecraft are controlled from a central control room where crew members operate the systems.
The Commission conducted an in-depth analysis of all Orbiter data, equipment and recovered hardware and found no indication that structural failure caused the accident. All fractures observed on Orbiter were typical overload fractures; no thermal distress evidence could be identified.
The Commission investigated whether the accident could have been caused by an anomaly with propellant. After performing detailed calculations for mean bulk temperature and subscale lot-acceptance motor-firing evaluations, detailed mean bulk temperature calculations indicated it was unlikely such an anomaly was the source of this accident. Furthermore, they reviewed External Tank construction records, acceptance testing procedures and premission analyses concluding there had not been structural failure of the External Tank as a cause.
The O-Ring
Failure of an O-Ring seal was at the root of this disaster. Due to extreme cold on launch day morning, making the O-Ring less malleable and allowing gases to leak out through its cracks.
At just 73 seconds into their mission, an explosion aboard Challenger claimed all seven astronauts onboard; these included mission commander Francis R. Scobee; pilot Michael J. Smith; mission specialists Ronald E. McNair and Ellison S. Onizuka as well as payload specialist Gregory B. Jarvis as well as teacher Christa McAuliffe.
Engineers working at NASA were well aware that O-rings could fail at lower temperatures, yet NASA management downplayed this risk by using results of an incomplete O-ring failure incidents versus temperature study that did not include successful launches (see graph). Had they reviewed all available data instead, engineers might have realized O-ring failure is more likely in colder environments and postponed launch accordingly.
The Booster
One minute into its launch, Elon Musk’s rocket booster exploded – a major setback in his efforts to create a spaceship capable of transporting humans to Mars and back.
At approximately the 73 second mark, shear force caused by flight caused one of the solid rocket boosters to breach, leading a fuel leak from one tank to ignite and ultimately leading to the destruction of both shuttle and its boosters.
The blast caused widespread debris to fall over algal mudflats south of the launchpad and salt-like particles were visible more than one mile away, creating difficulty for researchers trying to assess its full impact. Roads and wildlife refuge areas were immediately closed afterward making it hard for field researchers to evaluate damage assessments. Particles can cause pulmonary and respiratory issues depending on size and composition; some can even cause skin irritation; scientists worry about how far these particles travel as they pose serious environmental threats that must be cleaned up quickly according to them.
The Crew
After just minutes after liftoff, Challenger was gone from sight as white vapor billowed upward. Teachers called early recess to witness this spectacle from classrooms, while news cameras captured its grisly remains.
Mission commander Rick Husband and pilot Willie McCool may have survived when their rocket exploded, according to an analysis conducted by astronaut-doctors. Astronaut-doctors stated they may have experienced 6-15 seconds of consciousness after its explosion and breakup.
Eric Roesch, an environmental compliance specialist who blogs about SpaceX, states that SpaceX could have avoided its damages by creating superior launch infrastructure. While conventional wisdom dictates a flame trench around the tank to divert thrust away from it, SpaceX chose instead to save money by employing just two blankets – one insulating foam blanket and one thermal – on their external tank; that decision proved fatal; an 8″-by-8″ piece of hard insulating foam hit near where the shuttle’s wing met the booster and hit its wing near its connection.