Sunday, June 19, 2011

Total Lunar Eclipse in Retrospect


Despair and Delight

This is a logical corollary to my last blog post heralding the total lunar eclipse of June 15-16.  I had ended it with the fond hope that the prevailing cloudy monsoon skies all over south India would relent and provide a special window to view the event.  However, the weather continued to deteriorate and at around 4 PM on 15th June I sent out the following message of despair to many fellow eclipse chasers; "The weather in Mysore right now is so terrible and the prospect of any degree of clear skies tonight so remote that my promised next blog post may well have to carry the caption 'Episode of the Invisible Eclipse!'".  Would anybody believe that my next message to the same group of people on the following morning, after the eclipse, read; "We had a totally surprising and unexpected break in weather after around 11 PM yesternight.  This enabled the diehards among us to stay awake all through the night and see a wonderfully memorable eclipse."  I have rarely experienced such a magical transformation in nature from one extreme to another.  In response, there was a matching transformation of human emotions from despair to delight.  I recall a very similar experience with the total solar eclipse of 22 July 2009 which I had watched with similar feelings from a hilly place near Anji city in far way China (See my blog post titled "The Great Total Solar Eclipse of 22 July 2009 from China").  What a coincidence! When I mentioned this to a friend he told me that this must have been in answer to my silent prayers!  I am glad he didn't label it as divine intervention.

Around 10 PM that day the sky was so densely clouded over that I wouldn't have known where the Moon was and indeed needed to open the Google Sky Map application in my smart phone to find out.  As I was preparing to abandon my plans for the night and go to bed sooner than normal, my constant companion Chiranjeevi excitedly barged into my home around 11 PM and literally dragged me outside to show me the sky, now punctuated by a mockingly bright full Moon, surrounded by thin and swiftly parting clouds. We couldn't believe this incredible luck and quickly got back on track with our plans.  With a lingering suspicion of the weather, I opted to follow the unfolding events from the comfort of my home while the more adventurous Chiranjeevi opted to move out to a spot on the outskirts of the city some 15 km away with another friend Mr Krishnamurthy.  He took with him my Canon 350D SLR camera and an excellent 70mm spotting telescope. We kept in constant communication with each other throughout the night.  A number of other enthusiasts, who would otherwise have joined us, had apparently given up and retired to bed in blissful ignorance of the changed circumstances.

Progress of the Eclipse 

I set up shop on the roof of my two storey house, equipped with a 90mm Maksutov-Cassegrain Sky-Watcher telescope, an excellent Olympus 10x50 binoculars and my trusted high zoom Lumix digital camera mounted on a sturdy tripod.  A good measure of light pollution was provided by two nearby street lights that have always been a constant source of annoyance for me.  This didn't matter at all against the bright background of moonlight early on, but as totality approached I regretted not joining my two colleagues who had positioned themselves well away from disturbing lights somewhere on the outskirts of the city. 

As expected, the penumbral phase of the eclipse was hardly noticeable even as the Moon played hide and seek through thin layers of bright clouds.  Saturn and some of the brighter stars could be seen but the fainter stars were difficult to make out.  The interplay with the clouds continued into the early partial umbral phase of the eclipse. Thereafter, crystal clear skies set in and lasted well into the total phase.   The following images taken by me with my Lumix camera show the lunar surface before the eclipse and at different times during the progress of the partial phase from the eastern limb of the moon to its western limb right up to the onset of the total phase:


Disappearing Act

As expected, at any given time the eastern part of the lunar surface which was immersed in the umbral shadow continued to be visible, but very dimly, with a faint reddish hue.  The brightly lit western portion continued to be seen as brightly as before.  As the terminator, which is the curve demarkating the two portions, progressed westward, the overall brightness decreased rapidly and the night sky as a whole grew darker.  In this process, as Chiranjeevi later remarked, one could view in a short period of just about an hour the entire sequence of phases marking the waning of a full moon to a new moon over a two week long period of time.

When the totality set in, the last vestiges of the brightly lit part of the moon disappeared, the sky became almost, but not quite, as dark as on a moonless night and the western part of the now fully eclipsed moon could be seen distinctly brighter than the eastern part.  It may sound odd to talk about seeing a fully eclipsed moon, but I have already explained how this is possible due to the scattering of sunlight by the earth's atmosphere.  As the total phase of the eclipse progressed the western portion grew darker.  Eventually, at the midpoint of the total phase at around 1.40 AM, the lunar surface became uniformly illuminated with a very dark reddish hue - apparently much darker than what had been expected.   On the Danjon Scale of Lunar Eclipse Brightness, I would easily assign zero to the L value. When this happened, it was extremely difficult for me to spot the Moon with the naked eye but there was no difficulty doing so with the binoculars and the telescope.  However, Chiranjeevi and Krishnamurthy reported that they were able to spot the moon even during this time as they were placed well away from disturbing lights.  It was exhilerating to look through the telescope frequently and catch the moon in its changing phases, especially at totality, with a field of view encompassing the whole of the lunar disk.


The following two pictures taken by Chiranjeevi during the long period of totality are indicative of the wonderful sight of the total eclipse when the Moon appeared like a friendly ghost suspended in the sky, peeking back at the viewer.  The first picture was taken at ISO 1600 with a 10 sec exposure at f/6.3 on the Canon DSLR camera.  The two small streaks at lower right are star tracks.  The second picture shows the faint Milky Way patches and numerous stars, particularly in the Scorpius and Sagittarius constellations. The traditional shapes of these two constellations can be easily made out in the picture. It also shows traces of scattered green light from a laser pointer, including the light close to the pointer itself at extreme lower right. This picture was taken at ISO 1600 with a 30 sec exposure at f/4, also on the Canon camera.


The Net is flooded with pictures of this type from different parts of the world.  One of the best I liked was a spectacular stacked picture of the eclipsed moon with the surrounding star fields and the Milky Way patches. The reader will find it at:  http://www.spaceweather.com/submissions/large_image_popup.php?image_name=Amir-H.-Abolfath-spaceweather_1308187876.jpg

By now I had to give up any further attempts at photography since the long exposure times required a tracking telescope and my Meade 127mm Maksutov-Cassegrain has been under repair for sometime now. I thought I had actually lost the Moon, even through the binoculars, for about 10 minutes, but this could well have been due to a thin layer of haze covering the sky at that time.  Thereafter, there was a period of about 10 minutes when the sky became so clear that I could even see the patches of the Milky Way in Sagittarius from my light polluted location.  My colleagues reported that they were able to do this over a much longer period of time and more clearly as well.  Nowadays it is becoming virtually impossible to do this in the highly light polluted city skies, including Mysore.

Reappearing Act

By 2.30 AM the eastern portion of the lunar surface which was significantly brighter than the other part, came alive with a sliver of it showing through in bright light.  This marked the end of the total phase.  Thereafter, the brightly lit porttion started growing in size even as the other side grew markedly fainter.  It was like the mirror image of the events seen earlier leading up to the immersion of the moon into the umbral shadow.  After watching this for the next twenty minutes or so I decided to call it a day, not waiting to see the full moon in all its recovered glory.  My colleagues however stuck it out till the very end.

Media focus

Unlike total solar eclipses when the populist media goes into a frenzy with dark forebodings, the media glare during this eclipse was quite subdued and largely positive.  While the national level TV and print media gave generally accurate coverage both before and after the event, local media went about in their usual ways.  Astrologers and soothsayers had their usual say, with detailed prescriptions on how to protect oneself from or ward off the evil effects. 

Here are two samples of what was intended as some enlightened reporting: (i) The unusually long lunar eclipse, according to the astrologists, will have a negative effect on some zodiac signs, while it will benefit others; (ii) Natural calamities will affect the routine life of the countrymen, said astrologists when asked about the possible impact of this lunar eclipse on human lives.

I was interviewed by a Kannada TV channel on some technical aspects of the eclipse.  Among other things, the interviewer had pointedly asked me if there was any special type of radiation emitted during eclipses which would be harmful to people.  My responses in a two-minute video recording at home were whittled down to just twenty seconds in its actual news coverage of the day.  My obvious answer to the above question had been edited out.  To any viewer I must have appeared to be speaking irrelevantly.  This was followed by an equally short 'astrological evaluation' of the event by an appropriately attired astrologer who said something about the 'gravitational influence' of the event on people (no such influence exists), but otherwise mercifully refrained from predicting any grave consequences. 

A widely circulated Kannada newspaper gave equal space, side by side, to both the astronomical and astrological aspects of the impending eclipse.  I view this as a victory of sorts for science since the same newspaper had given three times as much space for the astrological aspects in its coverage of the great annular solar eclipse of 15 January last year (See my blog post titled: "Ring of Fire – The Great Annular Solar Eclipse of 15 Jan 10").  The astrological prescriptions this time included: (i) Performance of a 'Shanti' (penance) by people of just two 'rashis' who would be grossly affected by the eclipse (how considerate in excluding the vast majority of humans!), (ii) A much milder atonement by people of four other less severely affected 'rashis' by repeatedly chanting an exquisite sanskrit shloka invoking the mercy of the heavens during the eclipse (It didn't say how many times, but I believe the prevailing norm is one thousand), (iii) Abstaining from eating anything from as early as 12.30 afternoon on the 15th till the termination of the eclipse the following morning (One should welcome this strongly at least on health grounds), and (iv) Total exemption from fasting for children, the aged, the infirm and pregnant women (Again, how considerate, but how can one differentiate if birth dates and times are the sole criteria?).  In addition to these, there was of course the ever implicit warning, very often explicit as well, that it would be harmful to view any eclipse in any manner anytime!

Postscript

The eclipse appears to have been a near total wash out in several places in the south, including Bangalore.  During the total phase I got a phone call from a friend in Mangalore requesting help to locate the (fully eclipsed) Moon in what appeared to be reasonably clear skies there after a bout of rain earlier.  After some effort she did indeed manage to see the moon and thanked me profusely for the assistance.  The following day I got several calls and messages from friends who had managed to watch the eclipse successfully, particularly in Mysore which seems to have been specially favored by nature.  Incidentally, normal monsoon service was restored within minutes of the end of the eclipse. 

Dr S V Narasimhan of Virjapet, Coorg wrote that his motivation had been reinforced to such a degree that he spent the whole night peeping through thick monsoon clouds, getting occasional glimpses of the moon.  I wonder how many other people did so, even in cloudless skies. Since the event lasted such a long time, unlike a total solar eclipse, he would not have missed any of the important phases of the eclipse.  I am glad I have such good reason to mention him here as prominently as in my previous eclipse related blog posts.

Even in places where the eclipse may have been clearly visible, many inquisitive people may have been discouraged by the late hour of it. Those who missed it do not have to wait too long for the next such opportunity.  The next total lunar eclipse is due on 10th December this year and will again be visible all over the country, soon after sunset.  A great many more people should be able to see it for two reasons - very high probability of clear skies and the total phase occurring between 7:36 PM and 8:27 PM which is well before dinner time for most of them.  Of course there are lots of people who may refrain from seeing it even at such an opportune time.  The media can do a great deal to educate them, at the very least by not giving undue publicity to blind beliefs and superstitions. 

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