A collaborative wiki based project for collecting a database of simple star count observations, under the "Taare Sadak Par" program is at the Taarewiki.
"Taare Sadak Par" is a program that is meant to ensure that some handmade telescopes and a few dedicated amateur astronomers reach as many street corners of India as possible, to gather interested people around the telescope and ensure that they get to see some double stars, nebulae and clusters, the craters on the Moon, the Galilean moons of Jupiter, Saturn's rings and the phases of Venus. This will be a countrywide effort in which we will work with all interested educators working in this area and help some school teachers and senior students around the country into assembling a moderate aperture telescope and train them towards observations. We will then seek the help of these volunteers in reaching their neighbourhood children.
Just at present we are looking into assembling inexpensive prototype dobsonian reflectors and testing them out. These will be assembled from readymade mirrors purchased locally, rather than making the telescope through grinding and polishing the mirror. Although the cost of making the telescope this way is increasing - it would allow us to have more telescopes made in a short time through this process, as well as ensure a quality mirror for each telescope in a short time, particularly in areas where it would not be possible to hold a full fledged telescope making workshop. Efforts are also being put in, to ensure that the overall weight of the telescope is low and its ease of usage high. We are also looking into making a kit for a very inexpensive Galileoscope - a telescope with similar specifications to one of Galileo's telescopes, which will also be provided with its Keplerian eyepiece :-)
These telescopes will be fitted with a projection mechanism and screen, for safe viewing of the Sun, so that, the recipients of the telescopes can use them to help their neighbourhood view the 2009 Total Solar Eclipse and the 2012 Transit of Venus.
The Nehru Planetarium, New Delhi, conducts live shows with school students, on a daily basis. These live shows will be filmed, edited and mixed with other audio visual material and converted into educational CDs, that can then be exchanged with educational groups all around the country, to disseminate the thoughts behind this quantification of night sky pollution levels.
The taare sadak par program will also look at the Astronomical connection of almost all Indian festivals and chart out activities for each festival. Along with these activities, awareness against superstitious astrological beliefs will be inculcated.
And finally, the program will initiate long term projects for some of the very interested students, wherein they can look at archived data and visualise the growth in our understanding of 1.) Visual and spectroscopic binary stars, 2.) Star clusters and 3.) Nebulae. With modest telescopes, Galileo's observations of Mizar as a binary star and the Trapezium region, with measurements of the angular separations of stars, will be repeated by some interested groups of amateur astronomers. The latest developments in the understanding of these objects as spectroscopic binary stars, variable stars, and OB stars will be followed through long term student projects.
Dare we measure the diameters of stars?
Galileo had a very simple method described by Salviati, in his "Dialogue concerning the two chief world systems : Ptolemaic and Copernican" where a suspended thread is all that was to be used for measuring the angular diameter of a star.
Galileo himself used this method to determine the angular diameter of Vega and concluded it to be 5 seconds of arc, which, though much smaller than Tycho's exaggerated estimate, was yet much larger than its actual value measured in modern times, as 0.0029 arc seconds.
The figure here reproduced from reference 2., depicts the simple method that was used by Galileo for performing this "rope trick" of measuring a star's angular diameter.
Well, we now know that Galileo's method was very inadequate for measuring the angular diameters of stars (and impossible to really get anything from, below the limit of seeing, from Earth) - but, we could, perhaps try our hand at measuring the angular diameters of Venus (in twilight), with this method - just for fun :-) The changes in its angular diameter are so drastic, if the method works, it would give a wonderful feel about this to students, with practically no equipment. Reference 2 also talks of measuring the changes in the pupil diameter, using this method. That sounds like great fun, we will definitely attempt this, in our darkened sky theatre and outdoors, and post with the results :-)
Following these activities, we could hold awareness workshops for students that discuss interferometry and the modern day picture related to the measurement of stellar diameters (and parallaxes)
