Moon visible during daytime is not proof of flat Earth
Moon visible during daytime is not proof of flat Earth
(Reuters) - The moon visible during the day is not proof that the Earth is flat, despite claims shared online.
A clip was shared on social media in which a quarter moon (here) can be seen during the day, with the individual filming the clip questioning how the moon can be seen above the horizon with the Sun in the sky while also falsely claiming that the sun does not illuminate the moon.
“[The moon] is supposed to be on the other side of the Earth right now where it’s dark but as you can see, it’s out here with the sun,” the individual can be heard saying. (here).
The moon is commonly visible during the day, however, and it is not always directly opposite the sun, experts told Reuters.
“We can see the moon during the day often, when the moon is above the horizon (so it isn’t hidden behind the Earth) and some of the portion of the moon illuminated by the sun is visible to us,” Mike Boylan-Kolchin, associate professor of astronomy at the University of Texas at Austin told Reuters by email.
“The moon completes an orbit around the Earth roughly once every month (the orbital period is 29.5 days),” Boylan-Kolchin said. This means that some of the time, the moon is between the Earth and the sun, some of the time the moon is on the opposite side of the Earth from the sun, and sometimes it is roughly at the same distance as the Earth from the sun, he explained (here).
Day and night have nothing to do with it, Silas Laycock, associate professor of physics at the Center for Space Science and Technology, University of Massachusetts, told Reuters.
“People only notice the moon more often at night because then it is the brightest thing in the sky. At full moon, the moon rises as the sun sets and at the end of that night the moon sets at sunrise. Only at full moon is the moon actually up all night, and down all day,” he said.
Meanwhile, seeing a quarter moon (where the face of the moon appears half-illuminated) during the day is “very natural,” Boylan-Kolchin said, and tells us what portion of the lunar month we are in. Quarter moons occur when the moon is neither on the opposite side of the Earth relative to the sun nor on the same side, he added. During this lunar phase, we see part of the moon illuminated because only a part of the moon that is being illuminated by the sun is visible to us, he said.
“However, the best argument against flat Earth (using the moon) is that during a lunar eclipse, the moon enters Earth shadow,” Fe McBride, assistant professor in the Physics and Astronomy department at Bowdoin College told Reuters.
“This happens about every two years due to the moon’s inclined orbit (svs.gsfc.nasa.gov/4158). So, we see the shadow that Earth casts onto the moon. From all locations on Earth, during all eclipses, the shadow is round,” she said.
VERDICT
False. The moon is commonly seen during the day when the moon is above the horizon and some portion of the moon that is illuminated by the sun is visible on Earth.
