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There’s an occultation tomorrow (Oct 2nd, 2015) – where the Moon covers the star Aldebaran ( Rohini, as known to Indians). You can consider an occultation as an eclipse where one object in the sky covers another, as seen from the earth).
The west coast of the USA slightly misses it (or slightly gets it) depending on whee you are location. Check this link for more details.http://www.skyandtelescope.com/…/moon-hides-hyades-occults…/
I used the Neave Planetarium software to get some pictures of how it would appear in the SF bay area. I suspect the accuracy particularly when showing the Moon and the star is not perfect, but you can see through the 4 pictures how the Moon hovers over the star as time goes by.
Occulations are not as rare events, but occulations of bright stars is somewhat rare, as seen from a given place. Since there are only a few bright stars near the path that Moon takes in the sky and Aldebaran (Rohini) is the brightest star that the Moon can occult
Somehow this aspect of Rohini (that it comes very close to the Moon) made an impact on ancient Indians. So when they came up with a list of the 27 lunar mansions (“Nakshatras”), they were thought as the daughters of Daksha Brahma, and wives of the Moon. And out of these 27 wives, Rohini is said to be the most favorite of all to the Moon. It is not hard to see how this imagination come through given that the Moon occults Rohini quite regularly!
It’s been a common occurrence in Indian poetry, to compare exemplary humans Mount Meru. Even in current news reports, you may see the usage of this word to mean “great”, “of a tall order” etc.
Going back a few centuries,in a well known composition in Raga Mayamalavagoula, Tyagaraja calls Rama as Meru samana dheera, meaning Rama’s valor and majesty to that of Meru mountain. You can listen to an equally majestic rendition of the composition here by none other than Sri BMK. In his composition in raga Lalita, Syama Shastri calls out to the divine mother Parvati as “Sumeru madhya nilaye” , one who dwells in the great mountain of Meru. Given that Parvati is the daughter of Himavan, and wife of Shiva, who dwells in Kailasa, I think it was common practice to associate Mount Meru to be somewhere in the Himalayas. By the way, you can listen to an epic rendition of nannu brovu lalita here, by LGJ.
But where is Meru, exactly? If you believe the Wikipedia, it could be anywhere from the Himalayas to Tibet to Central Asia to Tanzania! But is it that difficult to identify it if it were so intertwined with our history?
The Mahabharata (in Bheeshma Parva) describes Mount Meru as a globular mountain made of Gold. Surely a poetic description, but not something that would help in identifying a geographic location. The Bhagavata too has several references to Mount Meru ( 5th Skandha), but that too leaves us with poetic descriptions that tell us it is “somewhere to the north of Bharatavarha”, “surrounded by the ocean”, “golden mountain” etc.
However, no need to despair. In addition to poets such as Vyasa or Kalidasa may have had colorful descriptions, but we are lucky have had people like Aryabhata and Varahamihira, who in spite of being a little fanciful, gave descriptions that would help us identify Mount Meru,
In the Golapada section of Aryabhateeyam, Aryabhata (5th century AD) says the following:
मेरुर्योजनमात्रः प्रभाकरो हिमवता परिक्षिप्तः
नन्दनवनस्य मध्ये रत्नमयस्सर्वर्तोवृतः ||११ ||
“In the center of the Nandana forest is the bright Mount Meru that’s a yojana in size, that is full of precious stones, and surrounded by the Himalaya Mountains” – Sure, this is as poetic as the description in the Bhagavata or Mahabharata. Not much use here.
स्वर्मॅरू स्थलमध्ये नरको वडवामुखश्च जलमध्यॅ
अमरामरा मन्यन्ते परस्परमधस्स्थितान्नियतम् || १२||
“At Meru Mountain, at the center of the landmass, live the devas; At Vadavamukha, at the center of water live the asuras. Now each of them think that the others are situated below them”
Again, not much help here – How does it matter where the devas and asuras live to identify Mount Meru? You are bound to ask me.
Thankfully, in the 16th verse in the same chapter, Aryabhata spills the beans!
देवाः पश्यन्ति भगोलार्धमुद्न्मेरु संस्थितास्सव्यं
अपसव्यगं तयार्धं दक्षिणावडवामुखे प्रेताः || १६||
“The devas situated on Mount Meru see half of the starry sphere, and the departed souls on the south end, see the other half of the starry sphere”.
Now this is a very good description of how the sky is seen from the Earth’s two poles. At each pole, only half of the starry sphere can be seen, and the halves are mutually exclusive. This implies that the Mount Meru should be located at Earth’s North pole, and Vadavamukha, at the South pole. However, it must be pointed out that that the shloka does not plainly say that Mount Meru is at the North Pole. For that, we must visit the work of Varahamihira (6th century AD).
In verse 34 of the 12th chapter ( titled भूगोलाधिकारः ), of Surya Siddhanta, a work of Varahamihira, we find the following description:
अनेकरत्न निचयो जाम्बूनदमयो गिरिः
भूगोल मध्यगो मेरुरुभयत्र विनिर्गतः
“Filled with different types of precious stones, the golden Meru mountain goes through the center of the globe onto either side”
This is as close as it gets to saying that the Mount Meru is on Earth’s axis. Note that the reference here is not to Jambu Dweepa (or India) but to “jAmbUnadamaya”. As per the dictionary, this term means “of Jamboonada gold, or of golden etc. Narayana Pandita’s Gudharthaprakashika commentary to Surya Siddhanta also adds a shloka to show how “Jambunadamaya” implies gold. It probably refers to gold panning in river waters.
The next verse (35) goes on to say the Gods live in the top of the Meru and the demons at the bottom of the Meru. Now compare it with the description by Aryabhata that I cited earlier in this post, and you will find that they are exactly talking about the same thing! What does go through the “center of” Earth’s globe and project to both ends? It’s nothing but the earth’s axis. Underneath all the glittering gold, and being the abode of devas and asuras being spoken about in the shlokas, we see the truth plainly told – that Meru refers to nothing but the earth’s axis. The top of Meru is the North pole, and the bottom of the Meru at is the South pole.
Then in the next few verses, Varahamihira talks about 4 (fictitious, although the text doesn’t explicitly say so) cities which are separated by 90 degrees on the earth’s equator. Incidentally one of these is called “Lanka” and is in Bharatavarsha – at a distance of one fourth the circumference of the Earth, due south of Meru’s top end. This implies the Surya SiddhantaKara knew that Bharatavarsha was close to the equator. However, the “city” which he calls Lanka can’t be in India because it is due south of Ujjain and on the equator, and falls in the Indian ocean and not on land. We can only assume that he made up these “cities” to be able to describe the globe, and the movement of the globe.
And later verses tell how at the top of the Meru there is a 6 month day, which there is a six month long night at the bottom of the Meru( verse 68). In verse 72, he says as you travel towards the Meru, in either direction, the altitude of the Pole star keeps increasing – This is a very direct way of saying that Meru (or the northern end of it) is nothing but Earth’s North pole.
So where is Meru? All these references confirm that Meru meaning nothing but the Earth’s axis. Leaving aside the stuff about the imaginary cities ( even there, the astronomy of these points, are accurately described) and Gods and demons living at either end of the Meru mountain, other astronomical descriptions are quite accurate.
Why didn’t I write down all the verses here? Because, there is nothing as gratifying as finding it in the source. If you are interested to read the verses I cited, click on the the PDF file in the link below:
http://www.wilbourhall.org/pdfs/suryasiddhanth035839mbp.pdf Check page 286 for the shlokas and the commentary.
Now it should leave you with no doubt about the identity of Mount Meru!
Last couple months we’ve seen some nice conjunctions of Jupiter and the Moon. On January 21st, they will come closest seen from the Earth. They would be seen about half a degree apart at the closest. As a comparison, the full Moon is about half a degree in diameter.
Here is a simulated view of the conjunction.
This conjunction is well placed seen from the western hemisphere, because it happens during the early part of night for this side of the Earth. The closest point being around 7:00 pm Pacific time. If you remember the Moon moves almost 13 degrees in one day,the conjunction may not appear so close from the eastern hemisphere unless you wait until late in night/early morning. In any case, don’t forget to look up at the Moon on 21st January 2013
This conjunction is also a good time to observe the movement of the Moon in the background of stars on the Ecliptic. Jupiter being farther away does not move much in a few hours. But the Moon is much closer, and also there is a the advantage of a bright Jupiter close by – So if you see the Moon at an hours interval a few times in the night, you will easily be able to see how the Moon has traveled towards East in the background of stars.
A bonus this time is the conjunction occurs in a very star-studded region of the sky – surrounded by prominent constellations such as Orion, Taurus, Auriga and Perseus. And by the way, the orange-red star close to the Moon & Jupiter is Aldebaran, also known as Alpha Tauri in sky-terminology, and is the 4th nakshatra Rohini, in the Indian lunar Zodiac.
Here is an article about Stellarium, that appeared on today’s issue of Kannada daily Samyukta Karnataka (9/27/2012). Click on the image for a enlarged view. My article is at the bottom of the page:
If the full page view is hard to read, you may choose to click on the following image, for a better resolution, but without the graphical elements:
(I wrote this article last year for ಅರಿವಿನ ಅಲೆಗಳು by Sanchaya).
By the way, I did not even notice another year has gone by for my blog. Surely, this has been the most inactive year for me on ಅಲ್ಲಿದೆ ನಮ್ಮ ಮನೆ!
By now, every kid on the internet and his or her baby-sitter know that the transit of Venus is a once-in-a-lifetime, twice-in-a-lifetime, or never-in-a-lifetime event. So, I am not going to dwell on that aspect of the transit!
In 2004, when the Venus transited the Sun, I was in the wrong part of the Earth .
Did you ask what do I mean by being “on the wrong part of the Earth”? You see, the transit is an event seen when the Sun is over the horizon. So if the planet were to go in front of the Sun during the night-time, hard luck. Just like a solar eclipse.
Transit 2004 Visibility Map from Wikipedia:
Luckily, I was in the right part of the Earth in 2012, so I did not want to miss the once-in-a-lifetime opportunity!
Transit 2012 Visibility Map from Wikipedia:
Adding to my luck, I was invited by a friend to watch the eclipse from his backyard telescope. Since Venus is so small compared to the Sun, the transit of Venus is better appreciated with an optical aid.
And here is the fantastic view through the 9-inch telescope – captured on my mobile phone.
We also looked through a welder’s glass, and it looked cool too. But could not take a picture through that. By the way, did you notice the sunspots in the picture above ? Compare them to Venus, which is about 12000 miles in diameter – and the enormous size of the Sun spots does strike you!