During the overnight hours of April 14-15, skygazers there will have a front-row seat as the full moon is painted red, creating what many call a "blood moon," as Earth's shadow creeps across the lunar disk.
"Lunar eclipses are exciting because nature puts on a free show for everyone to enjoy, and it causes us to look back at the sky and reexamine our place in the solar system and beyond," said astronomer Raminder Singh Samra of the H.R. MacMillan Space Centre in Vancouver, Canada.
Lunar eclipses occur only when there is a full moon and the sun, Earth, and moon are precisely aligned for our planet's shadow to turn out the lunar lights. (Related: "Solar Eclipse Myths From Around the World.")
During a lunar eclipse, the moon passes behind our planet so that Earth blocks the sun's rays from striking the moon. Due to the moon's tilted orbit around the Earth, one doesn't occur every month. And total eclipses usually happen once every few years, though there are sometimes more than one in a year.
"Since the moon's orbit around the Earth is slightly inclined, it doesn't pass through the shadow every month, therefore every year we get an eclipse twice a year—very rarely we can get up to five," said Samra.
Unlike solar eclipses, lunar ones are safely visible to the unaided eye. (A solar eclipse occurs when the moon comes between the Earth and the sun and blocks the disk of the sun.) (Related: "How to Safely Watch a Solar Eclipse.")
Lunar eclipses have been considered an awe-inspriring sky event for millenia, and ancient astronomers could do rudimentary but fundamental science with them, says Samra.
"Many cultures have mythologies associated with lunar eclipses so there has always been interest in the eclipses," said Samra. "The ancient Greeks were able to use the Earth's shadow cast on the moon to predict the approximate relative sizes of the two bodies."
CONTINUE READING...
No comments:
Post a Comment