Every so often, during a total lunar eclipse, the moon appears bright red. Havoc visits the world, raining down a trail of terror and despair. Before this, there are prophecies, which are dire. After, the events are often chronicled in movies starring lesser-known actors.“People associate this red color with the color of blood, which can be bad,” explained Frank Cianciolo, senior program coordinator at the University of Texas’ McDonald Observatory in West Texas. “And what happens when things are bad? People die. Pestilence and plagues and war and death.“It’s an episode of Game of Thrones at that point.”Actually, the subject slightly exasperates Cianciolo. “ ‘Blood moon' is what some people call it,” he said. “That’s not what astronomers call it.”Professionals call it simply a total lunar eclipse. For the record, Texans will be able to glimpse one in the wee hours of Tuesday, about 2 a.m., when sun, Earth and moon align in such a way that Earth blocks the sun’s light, darkening the moon.Although such eclipses occur with some regularity, today and Tuesday will feature the first in a series of four total eclipses in 18 months, a frequency that Cianciolo said is genuinely rare. After that, Texans won’t get a really good look at a total lunar eclipse until May 15, 2022.Obviously, not all such eclipses are bloody. The red light occurs because Earth’s nitrogen-based atmosphere filters out blues, leaving reds, which refract around Earth onto the moon. And if conditions are really favorable, it turns anywhere from bright red to rust-colored.“There’s no way to predict it,” Cianciolo said. The color intensity can change depending on weather systems and other factors, such as whether there have been large wildfires recently.Jennifer Herber, a spokeswoman for the Austin Police Department, said she didn’t know of any local data showing that blood moons were accompanied by an unusual volume of mayhem.“I can ask,” Herber said. “But,” she added, “I’m not sure who.”Despite his impatience with superstition, Cianciolo said he wouldn’t be shocked if a few gruesome things happen as the blood moon appears above Texas in a couple of days. In fact, statistically, it would be difficult to avoid.“Certainly somebody’s going to die,” he predicted.