Don't be fooled by a new astronomy hoax making the rounds on social media websites.
A widely shared story is claiming that Jan. 4 is "Zero Gravity Day," a date when people on Earth will be able to experience weightlessness while on the planet. The bogus post now appearing on Facebook and other websites at first blush looks legitimate. It shows a Twitter message that was seemingly posted by NASA and says a planetary alignment "will cause a gravitational fluctuation that will leave you weightless" at 9:47 a.m. PT on Jan. 4.
Other reports attributed the details regarding this supposed alignment to the late British astronomer Patrick Moore, who supposedly stated, "At exactly 9:47 PST AM on Jan. 4, Pluto will pass directly behind Jupiter, in relation to Earth. This rare alignment will mean that the combined gravitational force of the two planets would exert a stronger tidal pull, temporarily counteracting the Earth's own gravity and making people virtually weightless."
According to the article, people on Earth could experience this "Jovian-Plutonian Gravitational Effect" by "jumping in the air at the precise moment the alignment occurred." If they did so, Moore supposedly said, they would experience a "strange floating sensation."
This story is completely false. In fact, it is a repurposing of an old April Fools' Day joke perpetrated by Moore in 1976.
Moore, who passed away in 2012, was a British amateur astronomer who attained prominent status as a writer, researcher, radio commentator and television presenter. On April Fools' Day in 1976, Moore told listeners that they'd float momentarily if they jumped in the air at 9:47 a.m. that day.
Afterward, dozens of listeners phoned in to say the experiment worked.
There's no such thing as a Jovian-Plutonian gravitational alignment, of course. And for what it's worth, Pluto and Jupiter are currently on opposite sides of the sky as seen from Earth. Back in 1976, Moore couldn't have dreamt that his radio prank would be recycled for a worldwide audience on the Internet decades later.
— Joe Rao, Space.com
Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, the Farmer's Almanac and other publications, and he is also an on-camera meteorologist for News 12 Westchester in New York.
This is a condensed version of a report from Space.com. Read the full report. Follow Space.com on Twitter, Facebook and Google+.