Saturday, January 15, 2011

Ring of Fire! – The Great Annular Solar Eclipse of 15 Jan 10


After I started the blogging phase of my career last February, my initial posts focused so much on total solar eclipses and my incidental China travelogues that I had little time to write about yet another solar eclipse of great interest that I had witnessed exactly one year ago today.  To be better late than never, I am writing about it now to mark its first anniversary.  The event was the great annular solar eclipse that could be seen from most parts of south India on the afternoon of 15 January 2010.

How are eclipses caused?

Before I proceed further, let me explain in lay terms how eclipses are caused, something I should have done in one of my earlier posts.  At predictable times during the motion of the Moon around the Earth and of the two together around the Sun, the three objects can be found in a straight line for short durations of time.  When the Earth lies between the Sun and the Moon (on a full moon day), the latter can be found in the shadow of the Earth and hence sunlight will not be falling on it directly.  This is when a lunar eclipse occurs.  As seen from any point on the Earth, the eclipse may be partial or total.  One might expect the Moon to be completely hidden from view during a total lunar eclipse.  However, the whole of the Moon can be seen clearly as a faint coppery red object because of sunlight scattered by the Earth’s atmosphere falling on the lunar surface and thereby illuminating it.  It is a wonderfully beautiful sight to behold!  Would it be fair to regard the Moon as truly eclipsed?

When the Moon lies between the Sun and the Earth (on a new moon day), the latter can be found in the shadow of the Moon and hence sunlight may not be falling on certain parts of its surface at any given time.  This is when a solar eclipse can occur.  As seen from any point on the Earth, the Sun may be eclipsed, partially or wholly, depending on the geometry of the three bodies.  At any instant during a total solar eclipse, the Sun will be completely obscured and day turns very nearly into night for the duration of totality.  I say ‘very nearly’ and not ‘totally’ since scattering by dense clouds in the earth’s atmosphere can throw a bit of sunlight into the region of otherwise total darkness, something I noticed prominently during my sighting of the total solar eclipse of 22 July 2009 in China (see my blog post dated 23 Feb 2010).  The visibility of the solar corona during the total phase is one of the most spectacular shows put up by nature as vividly described in my earlier posts.  The rarity of total solar eclipses at any particular location on earth makes the experience all the more memorable.

Solar and lunar eclipses as seen from the Earth would not have been possible at all but for a very fortuitous and remarkable circumstance relating to the three celestial bodies.  The apparent sizes of the Sun and the Moon as seen by us on Earth just happen to be very nearly the same, approximately half a degree in angular diameter.  The sizes however are not constant because of small but distinct periodic variations in the distances between any two of the three bodies.  This makes the apparent diameter of the Moon sometimes slightly larger than that of the Sun; this is when the solar eclipse can be total.  When the reverse happens, we can have the outer parts of the Sun visible as a thin annular ring even when the three bodies are aligned perfectly; this is when an annular eclipse occurs.  This is what happened on the afternoon of 15 Jan 2010, but there was something very special about this event.  The duration of the totality phase at its peak was more than eleven minutes and this will be the longest in this millennium!*  The angular diameter of the Moon in relation to that of the Sun was very close to the smallest possible. For this reason the size of the Sun’s ‘ring of fire’ was so large that the reduction in the overall brightness of the normal Sun could barely be noticed.  I shall return to this point later to discuss an extraordinary post-eclipse news item appearing on the front page of a major English daily newspaper.

[*At its peak, the eclipse’s annular phase lasted for about 11 minutes and eight seconds, which was the longest since the annular solar eclipse on 4 January 1992, which lasted for about 11 minutes and 41 seconds. This duration will not be equaled or exceeded until the annular solar eclipse of 23 December 3043.]

The following diagram (grotesquely exaggerated and out of scale) illustrates the geometry associated with the formation of total, annular and partial solar eclipses:

The Location

The great annular solar eclipse of 15 Jan 2010 could be seen over a large area of the Indian subcontinent.  The totality phase itself was visible from most places in southern Tamilnadu.  The central line of the belt of totality passed through Dhanushkodi adjoining Rameshwaram off the eastern coast of the state (see the NASA-Espenak map below, zeroed in for this region).  For this reason, Dhanushkodi offered itself as the ideal location for seeing the eclipse.  Not only could the total phase be seen for the longest duration (over ten minutes) but also one could expect to see a near-perfect annular ‘ring of fire’ at the half way point of totality.  Naturally, that is where I was headed.  An added motivation was that I would be seeing the famous temple town of Rameshwaram for the first time after two ‘failed’ attempts earlier because of terrible weather conditions.  I would also be seeing the world famous 2.3 km long Pamban Bridge linking the island to the mainland since 1914.  The location presented a great photo opportunity for me.

 
[All pictures/illustrations in my posts can be blown up to their full size by clicking on an item and opening it in a separate window]

The Preparation

The eclipse day was a Friday and this was preceded by the strongly traditional Pongal /Sankranti festival (holi)day on 14 January.   It meant a long holiday weekend for most people and I expected a huge influx of tourists into a place like Rameshwaram.  I therefore started my preparations well in advance.  The first thing I did was to book hotel accommodation for the 14th.  I was glad to be able to do it online from the comfort of my home.  But the hotel itself turned out to be far from comfortable despite a hefty price tag.

I had planned to travel to Madurai from Mysore by train and take the road route to Rameshwaram thereafter.  I made an online railway reservation far in advance of the date of journey; yet found myself in the much dreaded waitlist.  Normally, the transition from the waitlist to the confirmed list is smooth, but this time I had no such luck.  I stayed put in the waitlist even three days before journey day and realized I had to do something about it.  When I discovered that the regular overnight bus services from Mysore to Madurai were fully booked, I sought the intervention of a friend who in turn had a friend in the railway offices.  Luckily this worked and I got the premium priced tatkal reservation just in time.

The Journey

I reached the famous temple city of Madurai on 14th morning by an uneventful and comfortable overnight train journey, but what followed was anything but comfortable.  I boarded an overcrowded private bus bound for Rameshwaram and a considerate passenger squeezed me into a part of his own seat, something not uncommon in India in both buses and trains.  I had to travel this way for the best part of the four hour journey.  The bus fare was ridiculously low, but I had to pay a heavy price in terms of having to put up with the horrendous cacophony emanating from an ‘in-house’ movie being played on a TV set.  One can rarely expect to travel in private buses, especially in Tamilnadu, without being subjected to such assault on the eardrums inflicted by gratuitous bus operators by way of ‘free entertainment’.  The bus conductor refuses to switch off or even reduce the sound volume on the plea that the passengers ‘demand’ such entertainment and he cannot afford to displease them.  I am not sure if most passengers indeed really demand such punishment, but they certainly don’t seem to object!  While it is easy to escape the video component of the entertainment, there is no way this can be done with the audio blasts from everywhere within the vehicle at full throttle.  I had taken with me a pair of ear plugs for such a contingency, but it was like fighting a huge fire with a water sprinkler.   It was with uncontrolled relief that I got out of this torture chamber at the bus stand in Rameshwaram, took a short auto ride and checked into the hotel located close to the famous temple complex in the town.

As it turned out, there was indeed a heavy influx of people into Rameshwaram, but most people had come only to visit the temple because of the special significance of the day and not to see the eclipse.  Only a tiny fraction of them had come primarily to see the eclipse and they were all to be seen at Dhanushkodi the next day afternoon.  It was not a small number but it was definitely not a crowd.

I spent the rest of the day exploring the temple complex and taking pictures both inside and outside.  Here are two representative pictures of the temple:




The Rameshwaram temple is often compared to the legendary Madurai Meenakshi Temple, but I rate the latter much higher in almost all respects.  The interior presents some spectacular views, like the one in the second picture, but it suffers from some poor maintenance, both inside and outside.  The floor appears to be always wet, grimy and difficult to walk on. 
 
Early next morning, on the day of the much anticipated eclipse, I found time to explore the famous Pamban Bridge and its surroundings.  Here is a picture of the historic railway bridge taken from the Rameshwaram end of the road bridge which is partially visible on the left.


Before moving on to Dhanushkodi I had some more time to spend both outside and inside the temple complex.  This was just before the visitors were shunted out and the doors were shut apparently to ward off any possible evil effects of the impending eclipse! This scene must have been reenacted that morning in most places in the country.

On to Dhanushkodi

Most of Dhanushkodi is a long and very narrow strip of sandy land surrounded by the sea and uninhabitable.  The vantage point I had considered for observing the eclipse was about 20 km away from my hotel and I could have easily reached it by a local bus.  However, no buses were plying that morning apparently because of the state governor’s visit to the town and the consequent disruption of road traffic!   After a long and futile wait, I tried to hire an auto. There were very few of them and the driver of one of them who was willing to take me on demanded such a huge amount that I thought under normal circumstances I could have hired a helicopter for such a sum.   It reminded me of a similar experience in China when I was trying to reach the hilly place from where I had planned to see the total solar eclipse on 22 July 2009.  I noticed a couple from Mumbai who apparently also wanted to go to the same place and for the same purpose.  We met, exchanged introductions and decided to join hands in the common endeavour.  We bargained hard, settled for an affordable and shared return journey and were soon on our way.  My companions were a recently retired seismologist from BARC, Dr Kovlankar, and his wife.  We got to know each other very well during the rather long journey on a difficult and narrow road with heavy one way traffic of mostly private vehicles. We got down at a convenient location well before the commencement of the totality phase of the eclipse, the initial phase having already started much earlier. 

The Ring of Fire!
My companions and I found ourselves among a fairly large number of small scattered groups of people most of them having come there for the same purpose.  Some of them had professional quality cameras and viewing devices, including small telescopes, equipped with solar filters.  I had taken the same improvised binocular device that I had used to observe the total solar eclipse in China on 22 July 2009 (See my blog post dated 23 February 2010 and one of the accompanying photographs), but had not planned on any photography.  I had avoided the temptation to carry my Meade 5” Maksutov-Cassegrain telescope with a Canon SLR camera attachment.  This was mainly because I was travelling alone and the attendant logistic problems.  While I have passionately practiced both Photography and Observational Astronomy as major hobbies, I have not tried to combine the two and done anything worthwhile by way of Astrophotography.  This is one of my major shortcomings, but living most of the time in heavily light polluted urban areas is perhaps mainly to blame for it. 

Dr Kovlankar had an excellent digital SLR camera setup along with a very good sheet of solar filter.  He was not sure if he could use the filter with the camera effectively.  We put our heads together and came up with a simple improvisation which worked wonderfully well.  Here is a picture of the camera with the improvised filter with which he took a series of decent pictures of the eclipse at regular intervals and produced a video clip later (See: http://picasaweb.google.com/Vinayakkol60/ECLIPSE15JAN2010?feat=directlink). 


Here is a subset of the sequence of pictures he took that day:

 
Even as the totality phase was approaching, the Sun was beating down harshly from a cloudless and beautifully clear sky. The three of us were lucky enough to be able to rest frequently under a nearby abandoned thatched roof apparently erected by some fishermen.  Most other viewers had to brave it out under a merciless sky.  Many visitors had come there only to see the place and the eclipse was an unexpected bonus for them.  Those who had any type of viewing device shared it readily with those who did not.  Some of them were even trying to look at the Sun through a slit formed between their extended fingers.  They must have discovered that the Sun was far too bright to be viewed this way and spared themselves the potential danger to their eyesight.
  
Soon it was time for the real show.  Just minutes before the annular phase started, we began to feel a slight drop in temperature giving us some respite from the heat, and an eerie silence set in among the viewers.  As the annularity set in, we could observe a marginal drop in the brightness of everything around us, but this was barely noticeable, especially since the viewer interest was focused on the eclipse itself.  As expected, the event lasted a little over ten minutes and at the mid-point in time (around 1:22 PM IST) we could all see a near perfect annular ring of the still very bright Sun.  The visibility was perfect all through and there was not a whiff of cloud anywhere in the sky.  As could only be expected, the much touted ‘ring of fire’ appeared like anything but a fire through any of the viewing devices. Yet it was a spectacular sight - in my view next only to that of a total solar eclipse.  Of course, the whole sequence of events could be seen only through safe filters, unlike a total solar eclipse which can be seen with bare eyes (in fact, should be seen with bare eyes) during the totality phase – and only during the totality phase.  The temperatures on the surface of the Sun are close to six thousand degrees, but a fiery appearance of the annular ring can only be seen through appropriate special filters, not through a neutral density solar filter most people were using.

The Return

As generally happens, the end of a major event comes as an anticlimax.  This eclipse was no different.  People started to pack up and leave as soon as possible to avoid a possible traffic jam.  We had no such concern since our vehicle was a highly maneuverable three wheeler.  I dropped my companions off at their hotel, went back to mine, packed up and was anxious to get back to Madurai as early as possible.

At the Rameshwaram bus stand I boarded a bus that was ready to leave for Madurai and this time had no difficulty getting into a comfortable seat.  But I had to endure the audio assault all over again and at the same decibel level for another torturous four hours before I reached Madurai.  I decided to never again place myself in a situation where I would have to travel in a private bus in Tamilnadu. Till now I have been successful.  However, I find that the disease has spread to Karnataka also and unbelievably, the latest victim is the Chamundi express train between Mysore and Bangalore.  I am thankful that other trains have been unaffected so far.
    
At Madurai bus station I had no difficulty getting into a KSRTC bus bound for Mysore on an overnight journey.  I boarded it only after ensuring that no TV set had been installed inside.  The next morning I was back home to reflect on another memorable experience.

Pall of Darkness … and Ignorance

When I browse my morning newspaper, a reputed national English daily, I generally do so from the last page backwards to the first page.  That morning I was curious to know if it carried anything on the great eclipse.  Sure enough it did, right there on the front page.  What I read was shockingly unbelievable.  Quoting its reporter from Dhanushkodi describing the experience of the previous afternoon, it went on to say, “….. A pall of darkness enveloped this region and a golden ring of fire appeared in the sky....”. It took some time for me to realize that this astonishing piece of (mis)information was indeed printed on the front page of such a widely circulated frontline publication.  I thought I should immediately convey my dismay to its editor and sent the following message by email:

Sir, I am bemused to read the description, “A pall of darkness enveloped this region and a golden ring of fire appeared in the sky....", appearing on the  front page of today's edition of your esteemed newspaper that is normally  well-known for its accurate and balanced reporting.  If your reporter saw anything like what he has described, he could not have seen the event from Dhanushkodi or, for that matter, from anywhere else along the path of annularity of the eclipse. I was in Dhanushkodi to observe this historic eclipse and saw, as expected, only a modest drop in the intensity of sunlight as the annularity phase approached and receded.  There was no darkness of any kind whatsoever.  Darkness appears only during total solar eclipses.  A spectacular ring was indeed seen through optical aids such as cameras,  binoculars and telescopes equipped with a solar filter, but this could hardly be described as a 'ring of fire' unless the view was through professional quality telescopes equipped with special types of filters.  Most people watching at Dhanushkodi had no such special equipment.  Your reporter appears to have fallen prey to the kind of sensationalism that afflicts many other newspapers and media in the country.

Not unexpectedly, the newspaper did not care to print my letter or issue any statement.  It might have been too embarrassing for the editor to accept that his reporter had committed a monumental blunder.  The only way the reporter could have seen a 'pall of darkness' enveloping Dhanushkodi that afternoon was by keeping his eyes shut at the time of the annular phase.  I wish he had also kept his communication channel shut at the same time!

I had copied my email to many of my friends and professional colleagues.  Most of them, including one from the Indian Institute of Astrophysics in Bangalore, wrote back to me in whole hearted support of my letter to the editor.   These were just lone voices drowned in a sea of ignorance and stupidity. 

A few days later, while scanning through a local language newspaper, I found a short column of factually accurate report on the scientific and technical aspects of the annular eclipse of 15 January.  However, on the same page, I found three long columns describing the evil portents of the eclipse in meticulous detail by a noted ‘astrologer’.  He had discussed at length how the event could influence almost every aspect of one’s daily life and gave detailed recipes on how to guard against each of them!  Of course they included avoidance of viewing the eclipse in any manner!  It is amazing how any established body of knowledge could support such outrageous claims and, adding insult to injury, also claim corrective possibilities through mere performance of some elaborately concocted and bizarre rituals.  Isn’t this just voodooism in a different, perhaps more refined, garb?  Anybody who tunes into any local language TV channel early in the morning cannot but be bombarded by all kinds of unscientific and irrational precepts and exhortations that seem to be designed just to insult human intelligence.   So much for the educational value of modern media. 

Tailpiece

Any of my posts on eclipses is incomplete without some form of reference to my great friend, Dr Narasimhan of Virajpet, Coorg.   This one is no exception.  Sometime after my return from the eclipse visit he drew my attention to his latest blog post in which he had written in considerable detail about his own experiences in Rameshwaram and Dhanushkodi.  Unknown to each other, we were at the same place at the same time doing the same thing!  We both felt very bad about not knowing each other’s plans and attempting a joint trip or at least meeting at Dhanushkodi which would have been so easy to do.  He sent me one of the photographs of the eclipse he had taken with a Nikon P90 camera that day.  It shows a near perfect annular ‘ring of fire’ with a date and time stamp (slightly in error) imprinted.  I am reproducing it here with my compliments:


Epilogue

Eclipse chasers like me will have to wait a long time for the next total solar eclipse from any location on earth.  It is due to take place partly over north eastern Australia on the morning of 13 November 2012.  The best place to view it appears to be the city of Cairns in Queensland (see NASA-Espenak map below).  I certainly don’t want to miss it.  An added attraction for me would be the Great Barrier Reef, one of nature’s greatest wonders, which can also be visited easily from Cairns.


5 comments:

A V G Rao said...

Informative. Liked this one very much

Anonymous said...

Good article although some details were avoidable as they did not contribute to the overall impact.

S N Gananath , Mysore

CGNagaraja said...

Sir:This Article is a must every Science Teacher. I enjoyed reading the long content, but the Mysore's glory and the activities in the sky through images kept me hooked to my computer, Thank you sir remembering me via mail. CGN

snigdha G said...
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Hai Baji said...
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