Today in History: 1973 Skylab launched, 1st Space Station
Skylab, America’s first space station and the first crewed research laboratory in space, lifted off on May 14, 1973, on the last Saturn V rocket. Although the Soviet Union orbited the first experimental space station called Salyut in 1971, the larger and more complex Skylab enabled research in several areas.
Skylab, America’s first space station and the first crewed research laboratory in space, lifted off on May 14, 1973, on the last Saturn V rocket. Although the Soviet Union orbited the first experimental space station called Salyut in 1971, the larger and more complex Skylab enabled research in several areas. These included life sciences, in particular the astronauts’ physiological responses to long-duration space flight, Earth sciences, and solar physics and astronomy, with additional experiments in materials processing. Skylab also gave students the opportunity to fly experiments in space. Three crews of three astronauts planned to spend 28, 56, and 56 days aboard the orbiting laboratory conducting 270 experiments.
The Skylab complex consisted of four major components: the Orbital Workshop (OWS), the Airlock Module (AM), the Multiple Docking Adapter (MDA), and the Apollo Telescope Mount (ATM). The Apollo Command and Service Module transported crews to and from Skylab and remained attached to the station throughout a crew’s occupancy to serve as an emergency escape vehicle. The OWS served as the main working, living, and sleeping compartment for the crews, and contained exercise equipment, a galley, and many of the scientific experiments, for the life sciences studies. Two large solar arrays on the OWS provided 12.4 kW of power to the station. The AM enabled astronauts to conduct spacewalks, while the MDA included a prime and backup docking port for the Apollo spacecraft and also housed the Earth Resources Experiment Package. The ATM contained telescopes for solar observations and four solar arrays for additional power. Once in orbit, the complex weighed 170,000 pounds, by far the heaviest spacecraft at that time.
Engineers at the McDonnell Douglas plant in Huntington Beach, California, converted the S-IVB stage of Saturn IB-212 into the Skylab OWS, delivering it to NASA’s Kennedy Space Center (KSC) in Florida on Sept. 23, 1972. They also converted the S-IVB from Saturn V-515 into a flight backup OWS. Workers in KSC’s Vehicle Assembly Building stacked the OWS and the other Skylab components onto their Saturn V rocket and rolled the vehicle to Launch Pad 39A on April 16, 1973. Following completion of a countdown test on May 3, the actual countdown for launch began on May 9. Engineers conducted a parallel countdown for the first crew expected to liftoff from Launch Pad 39B 24 hours after the launch of lab.
On May 14, 1973, the final Saturn V rocket thundered off Launch Pad 39A at NASA’s Kennedy Space Center in Florida to lift the Skylab space station into orbit. At first, all appeared to be proceeding normally, but at about 63 seconds into the mission, flight controllers in Houston observed the first signs of trouble. Telemetry indicated premature deployment of the micrometeoroid shield, designed to protect the station from debris and also act as a thermal blanket, and at least one of the OWS solar arrays, events that should have taken place only once the station achieved orbit. Less than 10 minutes after launch, after reaching its planned orbit, Skylab separated from the Saturn V’s S-II second stage and began a preprogrammed sequence to deploy the solar arrays and the ATM. Engineers in the Mission Control Center at NASA’s Johnson Space Center, led by Flight Director Donald R. Puddy, noted that while the ATM and its arrays deployed normally, sensors indicated that the main OWS arrays did not and were only generating 25 watts of power. Furthermore, temperatures inside the station began steadily rising to levels that would be intolerable for the crew, harmful to delicate equipment, and ruin onboard consumables, indicating the loss of thermal protection from the missing micrometeoroid shield. With the station underpowered and overheating, the entire Skylab program seemed in jeopardy. Flight controllers faced a daunting challenge. To maximize power generation by the ATM solar arrays, the best attitude was to orient them toward the Sun, but this caused maximal heating on the orbital workshop. Conversely, the optimal attitude to minimize the heat loads on the OWS significantly reduced power generation. After a day or so, controllers arrived at a compromise attitude to balance these competing factors while engineers and astronauts worked tirelessly to find more permanent solutions.
Review of the telemetry revealed that two major and interrelated anomalies occurred during powered flight, at 63 seconds and 593 seconds into the mission, as well as one close call. The first anomaly occurred two seconds after the vehicle passed the sound barrier, when aerodynamic forces tore the micrometeoroid shield from around the OWS and loosened both of the large solar arrays, with debris wrapping around one of them, preventing its eventual deployment. Because the vehicle had entered into a cloud deck during ascent, ground observers could not observe the event. As the shield fell from Skylab, its debris damaged pyrotechnic devices designed to separate the interstage ring between the first and second stages. A few seconds following burnout and jettison of the first stage, the interstage structure normally jettisons also, but in this case it remained in place. The S-II second stage engines ignited into the partially enclosed space, raising temperatures around the engines to near catastrophic levels. The engines finally shut down as planned, seconds from averting a launch abort. When Skylab separated from the second stage at 593 seconds, retrorockets designed to back the stage away from the lab impinged on one of the partially opened solar panels and tore it from the vehicle.
Managers delayed the launch of the first crew, planned to take place 24 hours after Skylab reached orbit, first by five days and, as troubleshooting continued, another five days until May 25. The crew, Commander Charles “Pete” Conrad, Pilot Paul J. Weitz, and Science Pilot Joseph P. Kerwin, flew back to Houston to begin training for a seemingly impossible mission to rescue Skylab. Engineers, managers and astronauts at NASA’s Marshall Space Flight Center in Huntsville, Alabama, and Johnson Space Center in Houston began working around the clock to find a solution to lower the station’s internal temperature and to deploy the solar arrays to allow the Skylab program to continue.
NASA Administrator James C. Fletcher formed an investigation board to determine the cause of the failure of the micrometeoroid shield. The board concluded that the shield’s inability to withstand the supersonic air currents during launch contributed to the failure. Also, prelaunch testing focused on deployment of the shield in orbit, not surviving the aerodynamically stressful launch environment. Developers of the shield, the board concluded, did not spend enough time talking with aerodynamicists about the shield’s launch environment and its potential impacts on the hardware. Finally, managers treated the shield as a subsystem of the launch vehicle and therefore did not assign a dedicated project engineer to the shield to consider design and load concerns.
As a side note, the Saturn V’s S-II second stage also entered orbit, as planned, becoming the largest although not the heaviest single object placed into orbit– Skylab 1 itself holds that distinction at 170,000 pounds. The stage weighed an estimated 79,700 pounds after venting its residual propellant and made an uncontrolled, and mainly unpublicized, reentry over the Indian Ocean on Jan. 11, 1975. Skylab 1, years after the departure of the final crew, made a highly publicized reentry over the Indian Ocean and Australia on July 11, 1979.
Read more here: 50 Years Ago: The Launch of Skylab, America’s First Space Station - NASA
Also on this day:
1607 English colonists establish the 1st permanent English settlement in America at Jamestown. Unknown to them they have landed amidst the worst drought in 800 years.
1787 Delegates gather in Philadelphia to draw up the Constitution of the United States
1796 English country doctor Edward Jenner administers his revolutionary cowpox-based vaccine for smallpox in Berkeley, Gloucestershire
1804 Meriwether Lewis and William Clark’s expedition sets out from St. Louis for the Pacific Coast, commissioned by Thomas Jefferson
1908 First passenger flight in an airplane
1940 British Local Defence Volunteers forms, an armed citizen militia designed to support the British Army during the Second World War. It is later renamed the Home Guard.
1945 Physician Joseph G. Hamilton injects misdiagnosed cancer patient Albert Stevens (CAL-1) with 131 kBq (3.55 µCi) of plutonium without his knowledge. Stevens lives another 20 years, surviving the highest known accumulated radiation dose in any human
1949 US President Harry Truman signs bill establishing a rocket test range at Cape Canaveral
1955 Warsaw Pact is signed by the Soviet Union, Albania, Bulgaria, Czechoslovakia, East Germany, Hungary, Poland and Romania
1960 USSR launch 1st (unmanned) space capsule
1986 Netherlands Institute for War Documentation publishes Anne Frank’s complete diary
1989 Demonstration for democratic reforms in Beijing’s Tiananmen square
2018 Successful memory transfer in snails achieved by scientists from University of California published in journal “eNeuro”
2024 Google unveils new generative AI features at its annual conference, forcing users to view AI Overviews at the top of search results despite them being factually incorrect 60% of the time
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1944 George Lucas - American film director, screenwriter, and producer (Star Wars; Indiana Jones; American Graffiti), born in Modesto, California
1940 Lieutenant Colonel Herbert “H.” Jones - British Commanding Officer, 2nd Battalion, Parachute Regiment and Victoria Cross recipient, born in Putney, London (d. 1982)
1936 Bobby Darin [Walden Robert Cassotto] - American singer (“Mack the Knife”; “Splish-Splash”; “Beyond The Sea”), born in The Bronx, New York (d. 1973)
1926 Eric Morecambe [John Bartholomew] - British comedian (Morecambe & Wise, Picadilly Palace), born in Morecambe, Lancashire (d. 1984)
1727 Thomas Gainsborough - English leading portrait painter (Blue Boy), born in Sudbury, England (d. 1788) baptism date
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2024 Gudrun Ure - Scottish actress (Super Gran; 36 Hours; Lady MacBeth; BBC Sorcerer), dies at 98
1998 Frank Sinatra - American singer (“Strangers in the Night”; “My Way”; “The Summer Wind”) and actor (From Here to Eternity; Guys and Dolls, The Manchurian Candidate), known as the “Chairman of the Board” and “Ol’ Blue Eyes”, dies at 82
1976 Keith Relf - British blues-rock singer and harmonica player (The Yardbirds - “For Your Love”; Renaissance, 1969-71), electrocuted while playing an improperly earthed electric guitar at 33
1925 Henry Rider Haggard - British author (King Solomon’s Mines, She, Dawn), dies at 68
1881 Mary Seacole - Jamaican businesswoman, author and nurse to British soldiers during Crimean War, dies at 76
Holidays on this day
Donate a Day’s Wages to Charity (Second Wednesday in May)
International Dylan Thomas Day
National Buttermilk Biscuit Day
National Chicken Dance Day
National Night Shift Workers Day (Second Wednesday in May)
National Receptionists Day (Second Wednesday in May)
National Root Canal Appreciation Day (Second Wednesday in May)
National Third Shift Workers Day (Second Wednesday in May)
Shades Day
The Stars and Stripes Forever Day
Underground America Day
World Facilities Management Day (Wednesday of the Second Full Week in May)
The Funnies:
Interesting (not necessarily extinct) animal of the day:
The last passenger pigeon on Earth died just more than 100 years ago. Housed at the Cincinnati Zoo and named “Martha,” she was the final holdout of a species that went from one of the planet’s most abundant birds to one of its highest-profile extinctions. And it all happened within a few decades, an early stage of what many scientists now agree is Earth’s sixth mass extinction event.
Passenger pigeons once accounted for up to 40 percent of the total bird population in the U.S., according to the Smithsonian Institution, with an estimated 3 billion to 5 billion of them occupying North America when European explorers first arrived. Many of those explorers reported seeing “countless numbers” and “infinite multitudes” of passenger pigeons flying overhead, with flocks said to be so large and dense that they sometimes blocked the sun for hours.
Yet by the early 1900s, the species had all but disappeared. Virtually no wild passenger pigeons could be found. Suddenly, Martha seemed to be the last of her kind.
Martha’s relatives had fallen victim to a familiar duo of threats that still haunt endangered species today: overhunting and habitat loss. Because passenger pigeons flew in such big, dense flocks, it was easy for colonists and settlers to shoot them. Professional hunters began killing and netting them en masse in the early 19th century, selling their meat and feathers in city markets. At the same time, the vast Eastern forests where passenger pigeons nested were being rapidly cleared for new farms and cities, further decimating the birds. Still, no conservation laws existed to protect them.
Wild passenger pigeons had grown scarce by the 1890s, spurring government officials to finally heed long-ignored warnings of conservationists. One of the last large nesting colonies was found in Petoskey, Michigan, and the Michigan Legislature passed a ban on netting passenger pigeons within two miles of a nesting area. But according to Encyclopedia Smithsonian, the law was weakly enforced and led to few arrests. The state then passed a 10-year ban on all hunting of the birds in 1897, but by then hunters couldn’t find many to shoot anyway.
From 1909 to 1912, the American Ornithologists’ Union offered $1,500 to anyone who could find a nest or colony of passenger pigeons. No one ever did, and Martha died two years later, foreshadowing an extinction crisis that kept snowballing over the next century. The U.S. endangered species list now includes more than 2,000 total listings, and the International Union for Conservation of Nature lists 9,741 species as “endangered” worldwide and 6,127 are “critically endangered.”
All five of Earth’s previous mass extinctions occurred long before humans evolved, but scientists say we’re seeing one now — and we may also be causing it. The passenger pigeon, along with other early casualties like the dodo and the thylacine, is now seen as a canary in the coal mine for this crisis. It’s too late to save Martha and her kind, but it’s not too late to make sure their deaths weren’t in vain.
In a timely sign of hope, the Smithsonian National Zoo announced today that one of the most endangered animals in the U.S. is now enjoying a “record-breaking” year of recovery, with 50 offspring born in 2011. The black-footed ferret was once thought to be extinct in the wild, but this month marks the anniversary of the discovery of a small remaining group in Wyoming. And now, thanks to conservation efforts informed by Martha’s cautionary tale, black-footed ferrets are making a comeback.
Source: Ode to Martha, the Last Passenger Pigeon
Quote of the Day:
“I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones.”
Albert Einstein
Video of the Day:
Happy birthday to David Byrne (1952):
In memory of Keith Relf (1976):
And Frank Sinatra (1998):
And BB King (2015):
Comic of the Day:
Credit: #1506; A Dash of Holiday Magic (Part 2) – Wondermark
Inspirobot Always Controversial, Occasionally Inspirational Quote of the Day:
Read @Vikingmichael’s heartless Spark! from yesterday https://community.spiceworks.com/t/spark-pro-series-13-may-2025
Don’t forget to leave some spice right here ↓
