An NPR story about the length of a day on Saturn picked up the following correction Tuesday:
This post originally stated that it takes the Earth 23 hours, 56 minutes and 4 seconds to complete one rotation and that we round up to 24-hour days. But that additional 3 minutes, 56 seconds takes actually into account Earth’s movement around the sun.
The correction comes after savvy NPR readers began a discussion in the comments below the article about different ways to measure the length of a day. While the article correctly notes that a sidereal day — the time it takes a celestial body to rotate relative to a fixed point — is actually slightly shorter than 24 hours for Earth, commenters observed that earthlings don’t actually round up the remaining minutes just to reach a tidy 24 hours. Instead, as the correction notes, the extra three minutes and 56 seconds is a result of the Earth’s movement relative to the sun.
NPR science correspondent Geoff Brumfiel, who wrote the story, tells Poynter that the “rounding up” comment was meant to be a “silly joke,” but that “NPR’s readers, being NPR readers,” spotted the mistake.
Brumfiel regrets the error. He does, however, stand by his original reporting on the length of a sidereal day.
“Basically, a day is a lot more confusing than it should be,” Brumfiel said.
