Blue moon and Mars together illuminate tomorrow night sky

On May 21-22, astronomers all over the world not only have the opportunity to follow the rare blue full moon but also can observe Mars in the closest position to the Earth.

According to Futurism, the Moon is like blue in the middle of the night sky. This is a very rare phenomenon, because dust particles in the atmosphere disperse light, causing the Moon to be blue when viewed from the ground.

Blue moon is a rare astronomical phenomenon.(Photo: Earthsky).

Earthsky.org offers two definitions of blue moon. According to the traditional concept, from the blue moon used to indicate the third full moon in a season there are 4 times the full moon. The season here is the time between the lice day (winter solstice or winter solstice) and the feces (spring or fall). Usually, there are only three full moons each season. Therefore, the full moon event takes place 4 times in an extremely rare and unprecedented season since August 2013.

Another definition of blue moon is the second full moon in the same calendar month. Astronomers calculated 235 times of the full moon in 19 calendar years, corresponding to 228 months. Thus, 7 in 19 years will have 2 full moons in the same month and 4 times of the full moon in a season.

Mars will be closest to Earth within a decade.(Photo: Alamy).

At the same time as the blue moon, Mars will lie in line with the Sun on May 22 , when Earth passes between Mars and the Sun this week. This event occurs every 2 years and 50 days. The brightness of Mars in the sky depends on the position of this planet and the Earth in orbit around the Sun. This year, Mars will be in the closest position to Earth within a decade, giving astronomers the opportunity to observe most clearly.