Total Lunar Eclipse of Jan 31st 2018
On January 31st, 2018 The Moon will go behind the Earth but this time pass through the shadow of Earth creating a geometry causing an eclipse of the Moon. The eclipse will be a rare and the first of its kind in last 150 years. Eclipses are not rare. They happen every 6 months but central (total/annular) eclipses are rare and happen less often. Central Solar Eclipses are visible from a very small place on Earth while central Lunar eclipses are are visible from almost 60% of the Earth.
Eclipses occur when Earth, Sun and Moon all lie in the same plane. Sun is the centre of solar system while other planets orbit around it in their orbital plane (consider a table top arrangement where Sun is at the centre while Earth moves around Sun on the top of the table. This top surface is called orbital plane). Similarly moons of all planets orbit around their parent planet in their orbital plane. Luna, our moon also goes around Earth in its own orbital plane. As the two planes are inclined by 5.15 degrees every 6 months The Moon will intersect the orbital plane and it will come in line with The Earth and The Sun. This causes The Moon to block sunlight and cause solar eclipses during new moon night or causes lunar eclipses as it passes through Earth’s shadow during a full moon night.
A blood red moon as seen on the darkest lunar eclipse of the century – 15th June 2011
The total lunar eclipse of 2018, is a very special eclipse due to its coincidence with important aspects of lunar calendar. First of all it is a “super moon”. Super moon is a label for full moon happening at the ‘perigee’ (closest distance from Earth). The distance at the time of full moon will be only 3,58,995 KM. The Moon will appear bigger than usual due to its closeness. The size of moon as seen from earth can vary by 15% between full moon at perigee and apogee (farthest distance from Earth). Also the full moon on this day will also be called as “blue moon”. The blue moon is name given to the second full moon happening in the same calendar month. With January 2 full moon, January 31st full moon becomes the second and hence the blue moon. Also The Moon will appear blood or copper red during the totality phase. One can also call this eclipse as “Super Blue Blood Moon”.
The celestial alignment of January 31st has many rare phenomena occurring at the same time. Here is a list of few worth mention:
- First Total eclipse since December 10th 2011 to be seen from India.
- Blue moon occurring after 26 months.
- 2nd Super moon of 2018.
- A rare coincidence of blue moon and lunar eclipse happening after 152 years.
A composite of Lunar Eclipse of December 10, 2011 with India Gate in the foreground
During a total lunar eclipse, The Moon turns red and does not disappear like in case of solar eclipses. The redness of Moon occur due to the passage of Sun’s light through the earth’s atmosphere on the edges. All the colours are absorbed during the passage but red colour is allowed to pass due to higher wavelength. Due to refraction, the rays of light bend and fall on the Moon. This light is then reflected back to Earth and the observers see a red moon. On Jan 31st, the Moon will be already under eclipse as it rises.
The following are the timings for the event:
- Penumbral Eclipse Starts: 16:21:15 IST
- Umbral Eclipse Starts: 17:18:27 IST
- Total Eclipse Starts: 18:21:47 IST
- Total Eclipse Ends: 19:57:51 IST
- Umbral Eclipse Ends: 20:41:11 IST
- Penumbral Eclipse Ends: 21:38:27 IST
- Sun Set: 17:56:25 IST
- Moon Rise: 17:56:21 IST
The Lunar eclipse is a beautiful sight and with a basic understanding of geometry and science, one can easily understand and correlate with what is happening in the sky. Though it is very common to have an eclipse in a year, the myths around the same often stop us from enjoying the marvellous views of nature. Following are a few myths prevailing in our society.
- Watching lunar eclipse can bring bad luck: The only bad thing that can happen to someone while watching a lunar eclipse is if he is walking while looking up, he may fell on the ground. Otherwise eclipses do not bring bad luck.
- Watching eclipse can damage your eye: Watching solar eclipses without proper protection to eyes can damage your eye. Lunar eclipses are not bright enough to damage your eye. You can enjoy seeing the blood red moon without worrying your eyes at all.
- The food becomes poisonous: Not true. Astronomers weather professional or amateur often enjoy watching eclipses for several hours and enjoy snacks/food/soda/water etc as the eclipse continues. The myth was first created while seeing shadow bands passing around on the ground and misinterpreted as snacks crawling on the ground. Today science has proven that the shadow bands are common during solar eclipse but not during lunar eclipse.
- Sacrificing human/animal life will bring good luck: Absolutely wrong it is. In the past some smart rulers and their smart ministers have made these kind of remarks but it does not bring any good luck to you. You sacrifice or not, the Earth and the Moon will continue to move in their orbit and the eclipse will be over on the above said time.
Do step out in the evening and look for the moon in the eastern sky. You can go to the terrace of your office/apartment or any place you can see clear horizon. Make sure you carry warm clothes, water and some food with you as you might not be able to leave the place before the eclipse actually get over due to its spectacular beauty and remarkable experience. Take out your camera and take pictures of this eclipse. The next eclipse will be on July 27th 2018 and there are very high chances that the moon will be behind the clouds.
A partial Lunar Eclipse as seen from behind the clouds on August 7th 2017. Monsoon clouds spoiled the fun
For more details about the eclipse or any upcoming eclipses, please feel free to contact me here.