To know about Zero Shadow Day or ZSD, TN Science and Technology Centre playing its part
Posted on: 18/Apr/2019 9:31:11 AM - No. of views : (3362)
The important piece of information is 24th April 2019 is Zero Shadow Day or ZSD. It is now said that the Tamil Nadu Science and Technology Centre is providing help for the students to understand the scientific facts associated with ZSD and to collaborate with other city students in India.
On 15th April 2019, an introductory programme on observational methods was conducted for about 60 school students by none other than the former scientist of National Centre for Radio Astrophysics, Mr. Niruj Mohan Ramanujam. It is now brought out that the same set of students would attend the observational activities on 24th April. By this the students would be sharing their shadow and time measurements with students belonging to cities like Bengaluru, Mangaluru, Delhi, Jaipur and Allahabad.
It was pointed out by the executive director of TN Science and Technology Centre, Mr. Soundararaja perumal that it is proposed to re-enact �Eratosthenes Method� by sharing the measurements of the students of Chennai-Allahabad, Bengaluru-New Delhi, Mangaluru-Jaipur �Srinagar on 24th April 2019. The length of the shadow cast would be measured by the students in Chennai.
It must be noted that this length of the shadow would be almost zero on 24th April noon and that is the time when the sun crosses Local Meridian. The instance of time at which the shortest shadow takes place would also be noted by the students. The point is local noon might take place at different times at different longitudes. It is revealed now that on 15th April at longitude of 82.5degrees the local noon occurred at 12 noon.
The amazing piece of information collected is on the same day the local noon occurred at 12:09 pm in Chennai. By this longitude of the place plus the speed of Earth�s linear rotation at the given longitude could be calculated. There would be some variation of linear speed at different latitudes. This was then confirmed by Mr. Soundararajan. The point to be noted is at Bengaluru the students would be conducting a similar experiment. The time at which the shadow is shortest in Bengaluru would not be same as Chennai.
