On May 10, sky-watchers in India, South East Asia, West Asia and Europe will see the moon snap Mars out of sight. Mars will appear to inch up to the edge of the moon, and hang on to it for a few seconds, before suddenly disappearing — only to reappear after an hour.

When a celestial body hides another body despite being situated far apart, the phenomenon is called occultation. Says Dr. P. Iyamperumal, Executive Director, Tamil Nadu Science and Technology Centre, Chennai: “The eye-catching event will happen in complete darkness. The moon will come directly between Mars and the earth. Mars will hide behind the crescent moon after about 7.30 p.m. (IST). In Chennai, for instance, it will happen at 8.05 p.m. It will take about 13 seconds for Mars to go behind the moon. The edge of the planet will touch the edge of the moon and slowly disappear… In Chennai it will reappear by 9.16 p.m. The exact time will depend on the location of the observer.”

The planet playing hide and seek with the moon will be a striking spectacle. A dim light will be produced by sunlight striking the “dark” side of the crescent moon after first being reflected from the earth’s surface, clouds and atmosphere.