NEW DELHI: Lunar eclipse is tipped to be the longest in the century and planetariums across India have made elaborate arrangements for enthusiasts. A total lunar eclipse occurs when the Earth's shadow moves across the Moon, blocking out light from the sun.

  1. The total lunar eclipse will coincide with another relatively rare celestial phenomenon known as the Mars opposition.

  2. Moon would enter the penumbral shadow of the Earth at about 10.53 pm IST. Nothing much will be noticeable to the untrained eyes for next 30-40 minutes. After that, one might notice a gradual change in the brightness on the lunar disk.

  3. By 11.54 pm, the Moon will enter the umbra of the Earth's shadow.  The dark shadow will now be seen progressing on the lunar disk. This will be quite noticeable to the naked eyes.

  4. Mars will rise around the sunset time and will set around the time of sunrise. An opposition happens when Mars is the closest to Earth in its orbit, both on the same side of the Sun.

  5. This time, Mars comes the closest to Earth as compared to any time in the last 15 years. As a consequence, it will also appear to be the biggest and brightest in the last 15 years. At this time, Mars will be just 58 million kilometres from the Earth.

  6. For an enthusiast, It would take a telescope equipped with a lens or mirror that is at least six inches in the aperture to discern even the major surface features of Mars.