Patchy high clouds are moving across San Diego County and might make it difficult to see Sunday night’s total lunar eclipse from some areas.
The National Weather Service says it does not appear that the skies will fully turn clear before midnight.
The total lunar eclipse began at 6:36 p.m. when the moon began to enter Earth’s shadow, about 19 degrees above the eastern horizon.
Initially, the changing conditions were difficult to see. But slowly, skygazers have been able to notice a darkening shadow spread upward, from the bottom of the moon. By 7:33 p.m., a very distinct partial eclipse will be visible.
The moon will enter total eclipse at 8:41 p.m., and it will be closest to the center of the shadow at 9:12 p.m. Totality ends at 9:43 p.m. That’s when the moon begins to move out of the shadow. The eclipse will end at 11:48 p.m.
Some science institutions, astronomers and media organizations are calling the event a “super blood moon,” which is largely hyperbole.
The word blood refers to the expected change in color of the lunar surface, which is likely to be red this time around. At least as it’s seen from San Diego.
“Lunar eclipses can appear anywhere from golden to deep red in color,” said Lisa Will, an astrophysicist at San Diego City College.
“The reason is the sunlight filtering through the Earth’s atmosphere before it falls on the moon. The sunlight is traveling above locations that are experiencing a sunrise or a sunset. The color of those sunrises and sunsets determine the color of the total lunar eclipse.
“The phrase ‘blood moon’ has become common for lunar eclipses, but ‘blood’ is the light of all of the sunrises and sunsets on Earth falling upon the moon.
“It’s beautiful, not scary, which is the usual connotation of blood.”
She added that “ ‘Super moon’ is the name given to the full moon phase when it also occurs at perigee, the closest point in the moon’s orbit to the Earth.
‘Super moon is not an official astronomical term, and unless you are a truly dedicated sky watcher, you’ll likely not notice any difference in the size or brightness of the moon due to its closer distance.”
The term irks many scientists, including well-known astrophysicist Neil deGrasse Tyson, who said on Twitter in 2017, “The very concept of a Super Moon is an embarrassment to everything else we call super: Supernova, Supercollider, Superman, Super Mario Bros.”
Unlike a solar eclipse, you do not need protective eyewear to safely watch Sunday’s lunar event. Instead, you need a clear view of the eastern sky, and good weather.
Scientists say that skygazers should be aware that they’ll be watching something of an optical illusion. The eclipse will appear to unfold slowly. But Caltech says the moon travels 2,288 mph as it orbits Earth.
The Fleet Science Center in Balboa Park will be holding an eclipse celebration, starting at 4 p.m. with hands-on science activities in the lobby. The center’s Giant Dome Theater will host a viewing of the popular astronomy show “Hubble” at 6 p.m.
And Will will discuss the eclipse at length during a planetarium show that will begin at 7:30 p.m.
The San Diego Astronomy Association also will have telescopes set up for public viewing from 4:30 p.m. to 10 p.m.
San Diego will not be in a position to see another total lunar eclipse, from start-to-finish, until May 2022.