The Day That Gravity (Allegedly) Weakened

In A Nutshell

Patrick Moore was a British astronomer with a sense of humor. On April 1, 1976 (and the date should have been the first clue) he announced on BBC 2 that an unusual planetary alignment was going to be taking place at exactly 9:47 AM, making Earth’s gravity momentarily weaker. Countless people jumped into the air when he told them to, and then called in to report their various experiences. And 35 years later, the hoax is still going strong.

The Whole Bushel

We’re not sure which part of the story is better: those zany British scientists, the gullible people who listened to them, or the fact that people are still falling for the 35-year-old joke today.

In 1976, BBC Radio 2 did a broadcast with British astronomer Patrick Moore. He talked about an amazing event that was going to happen that morning—April 1—at 9:47 AM. Pluto was going to be passing directly behind Jupiter in orbit, and the proximity of the large planet and the small one was going to play havoc with Earth’s gravitational pull.

That meant that anyone in the world who wanted to jump in the air at 9:47 AM would find gravity was temporarily suspended, and it was predicted that people would take as long as three seconds to float back down to the ground.

They counted down, they shouted, “Jump!” and waited for the phone calls to come in. And pour in they did, from people across the country who swore they had experienced the lack of gravity, the floating sensation, and, of course, a myriad of other occurrences.

One irate caller was mad because he jumped too high and hit his head on the ceiling. People said they floated around the room, that their furniture had temporarily risen . . . and of course, it was all a not-so-random April Fools’ prank.

It wasn’t all that random, because it was a spoof of theories put forth in a book that many people were taking seriously—The Jupiter Effect. Published in 1974, the book talked about a planetary alignment that would be happening in 1982 and the devastating effects it was going to have on our planet, from earthquakes to tides to coastal destruction. Los Angeles was going to fall into the ocean, sunspots were going to increase the solar energy bombarding the planet, and devastation would be complete.

It was all bollocks, of course, but as it was published by honest-to-gosh scientists, it had people worried. Even NASA said they couldn’t rule out the possibility of something catastrophic happening, although Moore and other scientists dismissed it as an outright hoax.

The April Fools’ joke on BBC 2 had been designed to try to show people just what a silly idea the whole thing was. Unfortunately, Moore might have been a brilliant scientist and astronomer, but he clearly wasn’t very in touch with the human psyche. In 1979, The Jupiter Effect was still being touted as scientific prediction, and even when 1982 came and went without any solar particle bombardment, the authors of the book quickly tried to rewrite their theory to fit past events.

And, if Moore was still alive today (he passed away in December 2012), he might be even more frustrated to see that the joke is still going around. In a little-circulated Internet rumor, January 4, 2014 was supposed to be Zero-G Day, a day when you would be able to jump into the air and float about for a good five minutes or so before gravity finally realized you were up to something you shouldn’t be.

Zero-G Day made the rounds and fooled a lot of people—most of them asking for translations to local time in the comments sections—but it didn’t take off quite the same way it did in 1976.

Show Me The Proof

Museum of Hoaxes: Planetary Alignment Decreases Gravity
Geekquinox: Sorry, folks. Jupiter and Pluto won’t let you float on ‘Zero G Day’