A total lunar eclipse - also known as a blood moon - will be visible in the skies over most of Australia on Tuesday. Once thought to foreshadow the wrath of God, evil spirits or malevolence, these days a blood moon is a spectacular scientific event. The eclipse will last around five hours and the moon will turn reddish in colour. A lunar eclipse occurs when the moon moves into the Earth's shadow, Adelaide Planetarium astronomy lecturer Paul Curnow said. "This can occur only when the sun, Earth, and moon are exactly, or at least very closely aligned, the technical term is in syzygy, with Earth between the other two, and only on the night of a full moon," he said. "The light from the sun shining on the moon's surface is blocked with the exception some light that has been refracted [bent] by Earth's atmosphere." Blood moons occur around twice a year and they are easy to see with the naked eye. Stargazers should look to the northeast, the moon will be sitting low. For those in Adelaide it will be around 17.3 degrees above the horizon, while in Sydney it will be at 25.9 degrees. The eclipse will take around five hours - from the moment of the first shadow, until there's no shadow left. Mr Curnow suggested people head outdoors 30 minutes before the maximum lunar eclipse. Maximum eclipse occurs a few hours after sunset and the time will vary depending on where you are in Australia. Starts at 8.09pm ends at 11.49pm. Total eclipse (when fully red) will last from 9.16-10.41pm. Starts at 7.09pm ends at 10.49pm. Total eclipse (when fully red) will last from 8.16-9.41pm. Starts at 7.43pm ends at 11.19pm. Total eclipse (when fully red) will last from 8.46-10.11pm. Starts at 6.42pm ends at 10.19pm. Total eclipse (when fully red) will last from 7.46-9.11pm. Starts at 6.43pm ends at 8.49pm. Total eclipse (when fully red) will last from 6.43-7.41pm. Unfortunately, Perth and the west coast will miss most of it as it will rise at about 2.4 degrees at maximum. "It will be really hard to see, if at all," Mr Curnow said. Just how red the moon will turn depends on the amount of dust in the air - the more dust, the redder it will appear. Lunar eclipses have long fascinated people across the globe and some ancient cultures believed it portrayed a bad omen. The Incan empire believed lunar eclipses were caused by an animal or serpent attacking the moon. Their custom was to scare them away by making as much noise as possible. IN OTHER NEWS: In mythology, the animal is often a jaguar and the blood-coloured moon is the result of the cat's attack. The world's earliest civilization, the Mesopotamian people, also believed the moon was being attacked and, by association, thought their king might be assaulted as well. During the eclipse the king would be hidden to protect him, and a substitute ruler put in place for this time.