Delhi's Own Star

Delhi's Own Private Star

Baldev Raj Dawar

About seven centuries ago we Dilliwalahs, built the Qutub Minar, to point a finger at the highest point in Dilli's sky, its zenith. It was also an apparent attempt to reach out for the stars. The sky in those days was far less polluted than it is today and therefore the stars were much easier to spot, recognize and to familiarize with. Dilliwalahs of those days might have noticed that a rather shy star of whitish hue visited and touched their city's zenith every night in winter. It is also possible that our ancestors developed a kinship with the star and regarded it as Delhi's very own star.


We now know that this star visits the zenith of our city's sky every day and throughout the year – except that in the summer months it visits us during the daytime and therefore, because of the Sun’s glare we do not notice its presence.

Does the star graze past the zenith of Delhi every day? No, it does it a little more frequently than 'every day'. To be precise, the star hits the zenith of Delhi after regular intervals of 23 hours, 56 minutes and 4.09 seconds – or say, 366 times in a year of 365 days.

Does this star also belong to Mathura, Agra or Panipat? No. It doesn’t. The star never touches the zeniths of those towns. The star rightfully belongs to Delhi and Delhi alone. Isn't it ironical that even in this age of science we Delhiites have not woken up to lay our rightful claim to it? We should do so sooner than any other town/city in the world.

The star we are talking about is no ordinary star. It is not to be ignored as only 'another' star among billions and billions of stars that inhabit our galaxy. Neither is it just one of those 3000 odd stars that we are able to see with our unaided eye on a clear moonless night. It is one of the 12 brightest stars of the northern sky that are easily visible in Delhi in spite of its thick haze of pollution. It is a prominent star with a magnitude as high as 1.7.

The star we are talking about is popularly known by its Arabic name, Elnath, meaning 'the one butting with horns'. It is the second brightest star in the constellation Taurus, marking the tip of one of the Bull's horns. Hindu astronomers perhaps named it Agni. Its scientific name is Beta Tauri and its astronomical address valid for epoch 2000 is: RA 5:26:18 and Declination +28:36:27.

Elnath belongs to the B7 III category of stars. Its color is whitish, with a tinge of blue. From its spectrum we know that its surface temperature is about 18,000 degrees Kelvin. (Remember that the surface temperature of our sun is much lower – about 5,700 K.)

There is another remarkable thing about Elnath. This star, the centre of our galaxy and our earth, all three, lie in a straight line, i.e., at an angle of 1800. Have a look at Elnath today when it touches the zenith of Delhi. Six months later, at the same hour, and at the same point of the sky, you will be looking at the centre of our galaxy in the constellation of Sagittarius.

Every year on about the 18th December Elnath arrives at the zenith of Delhi precisely at midnight. A day later Elnath will arrive at that point in our sky about four minutes before midnight. A month later Elnath would arrive there about two hours before midnight and two months later at about 8.00 p.m. In other words in mid-February Elnath arrives at the zenith of Delhi around 8 o' clock in the evening. That is perhaps the most convenient time, if not the most appropriate time, to view it.

Remember that the moment Elnath arrives at the zenith, the Qutub Minar is pointing its finger directly at it. The rays of light of the star, after having travelled through space a distance of 130 light-years, strike perpendicularly at Delhi's ground and parallel to the axis of the Qutub. These rays at that moment also run parallel to all the towers, poles and outer edges and surfaces of all the walls of Delhi. This moment in the daily life of Delhi is not only a moment of deep emotional relationship with Elnath but also a reminder that the two belong to each other.

We Delhiites must brook no delay in claiming Elnath as our own star. We can do that in two ways: First, by monitoring the movement of Elnath from night to night during the winter months. For this purpose, we can use straight iron pipes of one to two meter length and about two centimeters in diameter. These pipes may be hung loose vertically so that they freely point at the zenith. Looking from the lower end of the pipes we can view the zenith. Let all student hostels and parks of the city have these simple observatories installed for public use. At the predicted hour, people may first be invited to watch the star in the open sky overhead and later wait for its arrival at the zenith, e.i. the other end of the pipe.

Secondly, let us go a step further. Let there be annual celebrations in mid-February to mark the arrival of Elnath at the zenith in the evening sky. In honor of our star let people gather in parks all over the city well before 8.00 p.m., and hold a star party. In such a party let people watch their favorite stars and any planets in attendance that evening, and exchange information about the sky. Delhi Vidyut Board might also be requested to join these annual celebrations by switching off all streetlights for about 5 minutes the moment Elnath is sighted through the pipes. This will facilitate the mass sky watch.

And let there be no delay. The present relationship between Delhi and Elnath is temporary. It is going to last only for a couple of hundreds of years more. Due to precession of the Earth the pointing finger of Qutub is slowly moving away from the star. Soon this moving finger will stop pointing at Elnath. It will take more than 25,000 years before it returns to Elnath. During that long period of time the star will appear to us to be skirting Delhi's zenith a long way out.