AUSTIN (KXAN) — Over the past two weeks, a new conspiracy theory has hit social media websites: Where is our moon?
Videos on TikTok, under “#moongone”, show users looking around their local night sky and asking some variation of “Where has the moon gone?” Typically, these videos are accompanied by ominous music.
KXAN staff were able to visually confirm the moon’s presence multiple days during the period suggested by social media.
Some commenters attribute the “disappearance” to inscrutable actors, such as “the government” and divine providence. But the actual culprit? The interplay of the moon, Earth and the sun.
Judy Meyer, senior program coordinator at the University of Texas at Austin’s McDonald Observatory, said that TikTok isn’t always the best place to learn science.
“The moon moves around the Earth, and it takes a month to do that,” she said. “Sometimes, as the Earth is turning you see the moon at nighttime during that course of orbit around the Earth, and sometimes you don’t see it at nighttime, and that’s totally normal. So the moon didn’t go away.”
Meyer explains that the moon’s visibility depends on multiple factors, but that its phase is the most important.
“The altitude [of the moon] above the horizon changes over the course of a day, over the course of a night,” she said. “Sometimes the moon doesn’t get quite as high above the horizon.”
During the “missing moon” period, the moon climbed to 82.1° over the horizon on Sept. 27 and only up to 32.1° on Monday, according to the Moonrise and Moonset calendar on timeanddate.com. Tall buildings, hills, and even trees will disrupt our ability to see the moon during such low passes.
The moon’s phase also affects its luminosity — a full moon can reach nearly 100% illumination, from its surface reflecting the sun’s light. During a new moon period, that light dips to near 0% illumination. When it reaches that low, remaining daylight and light pollution can limit our ability to see the moon.
“In the winter months, we have more dark time, so maybe we notice it more,” Meyer said. “A few days after new moon, we’ve been seeing a little crescent moon just above the western horizon after sunset, but you have to be outside and looking the right direction at the right time.”
