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OGO-1 was the first in its series to launch and the last to return to Earth.
The 56-year-old geophysical satellite OGO-1 finally succumbed to gravity and burned up in the upper atmosphere on August 29, but only after causing a brief alarm for astronomers who are on the lookout for possible asteroid collisions.
Premiere of the successful summer plot
It sounds like the opening scene of a disaster movie from the late 1990s: astronomers from the Catalina Sky Survey (CSS) at the University of Arizona detected “a very small object that appeared to be on an impact path with Earth. , according to a NASA press release. 4,600 km (2,900 miles) to the west, another group of astronomers from the University of Hawaii’s Asteroid Last Warning System of Earth Impact, or ATLAS, detected the same object.
In case 2020 wasn’t unfolding enough that disaster cinema was coming to life, the first astronomers to notice the incoming object included two eighth-graders at Maui Waena Middle School, Holden Suzuki and Wilson Chao. The Hawai’i-based students saw the object in data from a telescope in the UK, Foukes Telescope North.
“I see them as scientists,” said their mentor, astronomer JD Armstrong of the University of Hawaii, “and if they know what they’re doing, then age doesn’t make much of a difference.”
It’s a perfect plot hook for the summer blockbuster. All it takes is a group of senior scientists and jaded military experts to ignore the kids (and a lonely renegade astrophysicist probably played by Jeff Goldblum) until it’s almost too late, then hire an oil rig crew to save. the world, with as much lens flare as possible. For better or for worse, real life didn’t follow the script.
Instead, CSS and ATLAS (both funded by NASA’s Planetary Defense Coordination Office, because real life is sometimes pretty cool even without the lens flare) immediately took a second look at the incoming object, making sure that they had really seen it.
The observatories, together with Suzuki and Chao, then shared their data with the Center for Near-Earth Object Studies of the Jet Propulsion Laboratory and the European Space Agency’s Near-Earth Object Coordination Center, who conducted some more detailed calculations of the path of the unknown object. Once the trajectory was mapped out, the astronomers realized that it looked familiar. What was heading for Earth turned out not to be an asteroid, but a relic of the Cold War.
The main goal of OGO-1 was to study the Earth’s magnetic field and how it interacted with the solar wind.
Blast from the past
When NASA launched the Orbital Geophysical Observatory-1 (OGO-1) on September 5, 1964, the satellite was a state-of-the-art spacecraft. At 487 kg (1,073 lb), OGO-1 was the largest satellite the United States had ever built (in contrast, the Hubble Space Telescope, launched in 1990, weighs about 11,000 kg). OGO-1 was NASA’s first real attempt at a standard observatory satellite, a precursor to later spacecraft such as the Landsat, the Jasons, and the ICESats.
The first space telescopes, the Orbital Astronomical Observatories, would not be launched until 1968. And like its successors, OGO-1 was the first in a series. NASA launched 5 more OGO satellites, one each year until 1969. Somehow, OGO-1 managed to maintain its decomposing orbit long after its 5 brothers had already fallen to Earth in streaks of fire.
OGO-1 carried 20 scientific instruments, mostly intended to study highly charged particles in the solar wind. The orbit of the satellite would take it through the radiation belts of the Earth to study how the solar wind interacted with the magnetic field of our planet. Other instruments on board would study interplanetary dust, cosmic radiation, the mass of Earth’s upper atmosphere, and radio astronomy. Some of those instruments were carried in packages on the satellite’s two solar panels, others were mounted on its hull, and others were mounted on 6 arms protruding from the main body.
Weeks before the launch of OGO-1, a confrontation between US and North Vietnamese warships in the Gulf of Tonkin led Congress to pass a resolution authorizing President Lyndon B. Johnson to send the US military to aid governments threatened by the “communist aggression” and the United States was about to become deeply entangled in the Vietnam War, where it already had 23,000 soldiers serving as advisers.
Animals ‘“House of the Rising Sun” was the No. 1 song on the charts that week (The Beatles’ “I Want to Hold Your Hand” took home the award of the year). Just two months earlier, President Johnson had signed the Civil Rights Act of 1964, which legally outlaws racial segregation and formal discrimination in the workplace, but the Civil Rights movement still had battles to win.
Five years later, in November 1969, NASA put the satellite into standby mode. Its 64 kb per second data transmission, which was always full of background noise and could only be used for 70% of its orbit, had degraded so much that NASA was only getting usable data from the satellite about 10% of the time. in June 1969. By November, even that had stopped.
OGO-1 took about 2 days to make a full orbit around Earth.
When OGO-1 fell silent, the United States had more than 400,000 troops in Vietnam, and the protests were a familiar part of the political landscape as public support for the war plummeted. American astronauts had walked on the Moon only a few months earlier. Civil rights leader Martin Luther King, Jr. had been assassinated in 1968. “Wedding Bell Blues” by the 5th Dimension topped the US music charts the week NASA put the satellite on hold.
Two years later, the agency stopped trying to communicate with the satellite. And 49 years after that, amid a global pandemic and mounting political tensions at home, OGO-1 finally fell from the sky.
OGO-1 re-entered Earth’s atmosphere just when and where the NEO Study Center predicted (it arrived about 25 minutes earlier and a little further east than expected). Witnesses in Tahiti saw the spacecraft smash high in the atmosphere about 100 miles east of the island around 4:44 pm ET on August 29, 2020. The pieces fell into the Pacific Ocean. .
While the return of a 56-year-old satellite is unusual, OGO-1 was not the oldest object orbiting Earth. That distinction belongs to Vanguard-1 – a glowing sphere with long antennae, launched in 1958 in part in response to the Soviet launch of Sputnik. Its batteries died in 1964, the same year OGO-1 was launched, but it’s still up there, silently orbiting about 600 km (375 miles) above the planet.
