Biggest Full Moon of 2013
23rd June, 2013
Supermoon? Not again. We have been fed with stories by electronic media of which natural calamity is awaiting to happen when the moon comes closer to earth every year, but the phenomenon of moon coming closer is happening for millions and millions of years now and if we believe the TV channels dishing out these news, we should not be alive ( for that matter no one on earth) right now as every year something big would happen and in course of so many millennia, all life forms should be annihilated by now. BUT this is not happening and thats a good news for masses, for a person who has some sense of logic, this is just a sensational news! Moon will not cause any earthquakes or Tsunami when it comes closer to earth. Lets just get into the crux of the matter by analyzing the news - " Moon will look biggest today or there is supermoon today"
Infact the term “Supermoon” was not coined by any astronomer or scientist but by an astrologer. Astrologer Richard Nolle in 1979, arbitrarily defined as:
...a new or full moon which occurs with the Moon at or near (within 90% of) its closest approach to Earth in a given orbit (perigee). In short, Earth, Moon and Sun are all in a line, with Moon in its nearest approach to Earth. But for in astronomy we term its as “Perigee Moon” and we do not use approximations but give exact values to it.
Supermoon taken by SPACE team on 19th March, 2011
Why it happens?
As each and every object in this universe revolves around another object, it does that circle (!!) in an ellipse. So it comes closer and goes farther away from a mean distance (in a circle it would have been the same throughout). These two positions are called peri(gee) or peri(helion) or apo(gee) or ap(helion) for earth and sun respectively. Thats what nature has given us in the basic rules which govern the motion of the bodies in space. Now Moon also has to follow the same rule and will be at perigee and apogee during its journey around the Earth. Any object’s apparent size depends on what angle does it make at our eyes. eg when you place thumb in in front of your eye it covers everything what you see and if you place the thumb away from your eye, it looks smaller and you can see the world around you along with the thumb. Same thing is happening with the Moon, at perigee it looks bigger and at apogee it looks smaller.
Now if we have full moon happening at perigee, obviously it would look quite big, on the other hand new moon at perigee will not have any meaning for us unless its a solar eclipse where it will be appearing bigger than the disk of the sun. There are instances when the new moon is at perigee but thats for the records only, we are concerned with full moon and perigee (Full moon itself is not an event which lasts whole day, its a point in the time when moon and sun have separation of 180 degrees, thats it) So to see a BIG full moon in the sky we should have it 1) Full Moon, 2) at perigee, 3) the perigee should come within few hours of full moon (or ideally at the time of full moon) and 4) that time of both the events should be happening when we can see the moon in our skies so that we enjoy the biggest Moon. Now all these factor will not be together most of the times but when this happens we see a BIg Full Moon as it happened on last biggest moon of 2011 in March (so called supermoon). This year also the next full moon on 23rd june is happening at the time of perigee so it should look big, in fact biggest full moon in 2011. But it won't bring any disasters, it would be a sight to watch even with naked eyes when it shines almost 14% more than a full moon at apogee. For those who are into records and numbers the definition of biggest moon or super moon becomes just a matter of statistics. 2011’s supermoon was at a distance of 356577 km from earth at 00:30 IST in the night of 19th March, 2012’s Biggest full moon on may 6th happened at a distance of 356953 km at 09:04 am IST, at a distance difference of around 376 kms from the 2011’s supermoon. This year’s Supermoon will happen at 16:41 IST at 356989 kms exactly at the time when full moon is happening..
So when you look at the moon in the night sky of 23rd june, it would look like same supermoon as of last year.
But for those who look the moon as something else from just being a number, it would shine brightly and giving a perfect view to look at. So just go out and enjoy the Biggest full moon of 2013 on 23rd junenight!!! Those who have interest in astrophotography can click the image and then compare it with other full moon images they have taken with the same lens to get some science out of it!!! Following image is an example of that where in 2011, full moon at perigee and apogee were clicked with same camera to show the difference in apparent size.
Its a good photo opportunity to the astrophotographers as well as amateur photographer to click the brightest of the Full Moons of 2013.
As the Full moon would be rising just after sunset, one can plan to shoot the Supermoon against the Foreground objects like monuments, buildings, structures to make it more interesting rather than just clicking the moon.
