Category Discoveries

When is national science day celebrated?

India celebrates National Science Day every year on February 28 to mark Sir C.V. Raman’s discovery of the scattering of light, also known as the “Raman effect”. For his discovery, physicist Raman was awarded the Nobel Prize in Physics in 1930. The recognition put India on the global science map, but proofs to India’s scientific acumen go all the way back to the 5th century A.D, when ancient Indians developed the concept of zero. Zero, the cornerstone of modern mathematics and physics, is seen as one of the greatest innovations in human history. There are records of ancient Indians being among pioneers in irrigation, veterinary medicine, cataract surgeries and atomism. Indian astronomy also has a long history stretching from pre-historic to modern times.

Colonial era exposed a number of Indians to foreign institutions. Scientists from India also appeared throughout Europe and their work saw recognition and acceptance on a wider platform. Since Independence, India has built a number of satellites and sent probes to the Moon and Mars, established nuclear power stations, acquired nuclear weapon capability and became self-sufficient in the production of food and medicines. Not to mention the developments in meteorology, communication and Information Technology.

 

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What is the Background of the Keezhadi excavation?

Excavations at Keezhadi, an archaeological site in Sivaganga district near Madurai, Tamil Nadu have brought to light significant details about the Sangam era. The report on the fourth face of the archaeology survey, undertaken at the site in 2018, was released by the Tamil Nadu Archaeological Department (TNAD) last month. It describes the findings are turning point in the cultural historiography of the ancient Sangam era.

As many as four phases of excavations have been carried out in Keezhadi, while the fifth one, which began in June 2019, is underway. The first three faces were conducted by the Archaeological Survey of India (ASI) and the fourth and the fifth phases are under the ambit of the TNAD.

In 2013-2014, the ASI begin exploration in Tamil Nadu, along the banks of the river Vaigai. More than 290 sites were identified in Theni, Dindigul, Madurai, Sivaganga and Ramanathapuram districts for excavation, Keezhadi, a village 12 km south-east of Madurai in Sivaganga district, was one of them.

In Keezhadi, the first phase of excavation begin in 2015. The site began yielding rich artefacts such as potsherds with Tamil-Brahmi inscriptions, deep terracotta ring wells, big storage pots, pots with spouse, decorated pots, white-painted black ware, black and red pottery and beads made of semiprecious stones. Further excavations at the Pallichanthai Thidal in Keezhadi pointed to an ancient civilisation that thrived on the banks of the Vaigai.

Major findings mentioned in the latest report

The Sangam area could be 300 years older than thought. Culture deposits on earth date back to a period between sixth century BCE and 1st century CE. This is the first time the date has been officially announced by the TNAD.

The Keezhadi site provides overwhelming evidence of the presence of an urban settlement. The artefacts suggest that urbanisation took place on the Vaigai plains in Tamil Nadu around 6th century BCE, making it contemporary to the Gangetic plain civilization. The discovery of brick structures with classical features such as platforms, ring wells, rectangular tanks, square tanks with extended structures, and channels vouches for the presence of an urban culture there.

Sangam people may have participated in recreational activities as many as 110 dice made of ivory have been unearthed.

The Keezhadi findings push back the date of the Tamil-Brahmi script to another century, i.e., 6th century BCE.

Fifty-six Tamil-Brahmin inscribed potsherds have been recovered from the site of excavation undertaken by the TNAD alone. These suggest that the residents of the Sangam era attained literacy or learned the art of writing as early as 6th century BCE.

There are also other markings alongside the Tamil-Brahmi symbols which apparently suggest a connection with the Indus Valley civilization. Artefacts with ‘graffiti’ or ‘markings’ establish a possible link between the scripts of Indus Valley Civilization and Tamil Brahmi, which is the precursor to modern Tamil.

Skeletal fragments of  animals were used to predominantly for agricultural purposes.

Pottery specimens confirm that water containers and cooking vessels were shaped out of locally available materials.

 

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Who discovered the radioactive element radium?

 

                         Marie Curie and her husband Pierre began their research into radioactivity in 1895. They soon discovered the new element thorium, and in 1898 they discovered two other elements — polonium and radium. They received the Nobel Prize for physics for this work in 1903, although they shared the prize with Henri Becquerel, who researched the same subject. After her husband’s death, Marie continued her research, winning a second Nobel Prize before dying in 1934 of cancer caused by unprotected exposure to atomic radiation. A new element discovered in 1944 was named curium in her honour.

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Who developed the theory of relativity?

   

                      Albert Einstein (1879-1955) was a physicist who was born in Germany but lived in Switzerland and the USA in later life. He developed the theory of relativity, which led to the famous equation E = (which very few people actually understand).

                     Einstein’s work is the basis for most of our theories about the nature, history and structure of the Universe. He laid down the rules that govern objects moving close to the speed of light, and explained why travel at this sort of speed could distort time itself. His work also proved invaluable in the development of the atomic bomb.

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How did frogs’ legs lead to an understanding of the nervous system?

                              Luigi Galvani (1737-1798) was an Italian scientist. He accidentally noticed that severed frogs’ legs twitched when the nerve was touched with a pair of metal scissors during a thunderstorm. Alessandro Volta (after whom the volt is named) explained why this happened. It was because an electrical current was produced between two metals, which provided the stimulation to the nerves. This discovery later led to the realization that the nervous system works by means of electrical signals.

 

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Who discovered the double helix?

 

                    The scientists James Watson and Francis Crick studied genes in an attempt to find out about their structure. The genetic material DNA (deoxyribonucleic acid) is a complicated molecule, and it had been difficult to understand how DNA could copy itself when cells reproduce. Watson and Crick found that it was shaped like a stepladder twisted into a spiral, and that if the two sides were pulled apart the ‘rungs’ of the ladder would automatically reproduce the rest of the molecule.

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