If skies are clear New Year’s Day, the moon will be delightfully large and bright as it edges over the horizon right around sunset.
This first full moon of 2018 will be a supermoon—the result of the moon’s orbit around Earth being an imperfect circle. When the moon is nearest Earth, it can appear 14 percent larger, and 30 percent brighter, than when it’s at its farthest orbital point.
Moonrise will be at 5:31 p.m.―perhaps earlier if you’re on an east-facing hillside, or later if your view is blocked by a mountain. (The sight will be similar Jan. 2, when the moon rises at 6:37 p.m., still 97.6 percent full.)
Perhaps you’ve noticed before how the moon seems bigger on the horizon than later, when it’s higher up. This is just an illusion. Find out why your brain is fooled, and how to prove it’s an illusion, here.
Supermoons aren’t particularly rare—it’s a normal astronomical occurrence with a fancy name. But something rare will happen Jan. 31: The month’s second full moon, which will also be a supermoon, will involve a total lunar eclipse. Now that’s a cosmic event you won’t want to miss.
SOURCES: NASA; timeanddate.com