A jaguar is going to attack the moon on September 27, at least this is what the Incas feared happened every lunar eclipse. Nearly 600 years later, we now know the truth.
The two most noticeable celestial objects in the sky are the sun and the moon. The sun, moon and Earth together make an astronomical system and are responsible for eclipses and lunar phases.
The Earth rotates around its own axis as it orbits the sun. Similarly, the moon rotates around its own axis as it orbits the Earth. While the Earth rotates roughly 365 times during its trip around the sun (thus 365 days in a year), the moon only rotates once each month during its trip around the Earth. This happens because the moon’s rotation and orbital periods are tidally locked. This is also why the same side of the moon always faces Earth. As the moon, which is spherical, orbits Earth it reflects the light from the sun, and creates different lunar phases.
Depending on where the moon is located with respect to the sun and Earth, we see more or less of its surface. When the moon is located between the sun and the Earth, we cannot see it at all, as the side of the moon illuminated by the sun is the same side not facing the Earth; this is known as a new moon.
In contrast, when the moon is located on the opposite side of the Earth, the side illuminated by the sun is the one facing the Earth; this is known as a full moon.
At any given time, the side of the moon that is being illuminated is the one facing the sun. Thus, the half point phase between new and full moon (knows as the first quarter) resembles a D, and the half point phase between full and new moon (known as the third quarter) resembles an inverse D.
Like the sun, the moon rises in the East, and sets in the West, but its timing is different every day because it changes its phase as it rotates around the Earth. A new moon, albeit not visible, rises and sets with the sun (normally around 6 a.m. and 6 p.m.). As the moon phase increases, it raises and sets later each day, which makes the moon visible during the day. A full moon, visible at night, rises as the sun sets, and sets as the sun rises (around 6 p.m. and 6 a.m.). After a full moon occurs, the moon phase decreases over time, causing the moon to raise and set later each day, which will once again make the moon visible in the morning.
A lunar eclipse occurs when the sun and the moon are in opposite sides of the Earth. Thus, the moon is full. An eclipse only occurs when the the Earth blocks the sun’s light from reaching the moon. This would happen every month if the moon’s and the Earth’s orbit were on the same plane, but they are not. The moon’s orbit is inclined to the Earth’s orbit by about five degrees. Nevertheless, it is scientifically possible for a lunar eclipse to occur about once every six months, even if only partial at times, since the Earth’s shadow only covers part of the moon. During a lunar eclipse the moon turns a reddish hue during totality. This is because light from the sun is refracted by the Earth’s atmosphere and indirectly lights up the moon’s surface.
On Sunday, September 27, a total lunar eclipse will be viewable from Miami. The lunar eclipse will begin at 9:07 p.m., reach totality at 10:47 p.m., and will end at 12:27 a.m. We will have to wait until January 20, 2019, to see another one with the same level of clarity from the Magic City.
The Inca used to drive the jaguar away by shaking spears at the moon and making noise. While we know there is no jaguar, Frost Science and 1 Hotel South Beach will be joining forces for a lunar eclipse viewing party at the Rooftop at 1 Hotel, on Sunday, September 27, beginning at 9 p.m. Music will be provided by DJ Leo Medina and Frost Science will be navigating the night sky for guests. The beach will be the most visible place to see the lunar eclipse until its 2019 return.
Dr. Jorge 