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In 1986, the Government of India designated February 28 as National Science Day, to commemorate the announcement of the discovery of the “Raman effect”.

The Raman effect won scientist Sir CV Raman the Nobel Prize for physics in 1930. It was also designated as an International Historic Chemical Landmark jointly by the American Chemical Society (ACS) and the Indian Association for the Cultivation of Science (IACS).

The theme of this year’s science day is “Women in Science”. On Friday (February 28), Prime Minister Narendra Modi tweeted: “National Science Day is an occasion to salute the talent and tenacity of our scientists. Their innovative zeal and pioneering research has helped India and the world. May Indian science continue to thrive and may our young minds develop even greater curiosity towards science.”

The Raman Effect

In 1928, Raman discovered that when a stream of light passes through a liquid, a fraction of the light scattered by the liquid is of a different colour.

Raman conducted his Nobel-prize winning research at IACS, Calcutta.

While Raman was returning from London aboard the SS Narkunda in a 15-day voyage, he started thinking about the colour of the deep blue Mediterranean sea. He wasn’t convinced by the explanation that the colour of the sea was blue due to the reflection of the sky.

As the ship docked in Bombay, he sent a letter to the editor of the journal Nature, in which he penned down his thoughts on this. Subsequently, Raman was able to show that the blue colour of the water was due to the scattering of the sunlight by water molecules. By this time he was obsessed with the phenomenon of light scattering, the commemorative booklet says.

Significantly, it notes that the Raman effect is “very weak” — this is because when the object in question is small (smaller than a few nanometres), the light will pass through it undisturbed. But a few times in a billion, light waves may interact with the particle. This could also explain why it was not discovered before.

In general, when light interacts with an object, it can either be reflected, refracted or transmitted. One of the things that scientists look at when light is scattered is if the particle it interacts with is able to change its energy. The Raman effect is when the change in the energy of the light is affected by the vibrations of the molecule or material under observation, leading to a change in its wavelength.


Central Theme : “Red snow” or “watermelon” is a phenomenon that has been known since ancient times. Now, it raises concerns about climate change

Over the last few weeks, photographs of “red snow” around Ukraine’s Vernadsky Research Base, off the coast of Antarctica’s northernmost peninsula, have gone viral. “Red snow” or “watermelon” is a phenomenon that has been known since ancient times. Now, it raises concerns about climate change.

Red snow in Antarctica: Why it happens :- It is the algae that give the snow its red tinge. This alga species, Chlamydomonas Chlamydomonas nivalis, exists in snow in the polar and glacial regions, and carries a red pigment to keep itself warm .

What watermelon snow signals:-In turn, the red snow causes the surrounding ice to melt faster, a 2017 study from Alaska Pacific University said.
The more the algae packed together, the redder the snow. And the darker the tinge, the more the heat absorbed by the snow.
Subsequently, the ice melts faster. While the melt is good for the microbes that need the liquid water to survive and thrive, it’s bad for glaciers that are already melting from a myriad of other causes.

These algae change the snow’s albedo— which refers to the amount of light or radiation the snow surface is able to reflect back. Changes in albedo lead to more melting.

2) Explained: Why 5.8 million YouTube videos have been removed in three months:- YouTube removed over 5.8 million videos between October and December 2019, a newly released Google Transparency Report shows. The highest number was from the United States, at 1.1 million. Videos from India were at third place, at over 7.5 lakh.

Other removals

During the period, YouTube removed over 2 million channels, 89% of them for spam and misleading content.

Over 540 million comments, too, were removed. Spam and misleading comments accounted for 59%, followed by hateful and abusive comments (25%).

Editorial : Slower still

Central Theme :– As growth declines to 4.7 per cent in the third quarter, NSO expects that economy has bottomed out. There are risks

India’s economic slowdown deepened further in the third quarter of the current financial year. The economy grew at 4.7 per cent in the October-December quarter, down from the revised estimate of 5.1 per cent in the second quarter.

If we look at the Deeper analysis: At the aggregate level, gross value added grew by 4.5 per cent in the third quarter, down from 4.8 per cent in the previous quarter. But excluding public administration, defence and other services, which largely connote government spending, value added by the rest of the economy grew by a mere 3.7 per cent in the third quarter, down from 5.2 per cent in the same quarter last year.

Construction activity also slowed down reflecting the continued dismal performance of the real estate sector.

The other worrying aspect is that gross fixed capital formation, which represents investment in the economy, has now contracted for two straight quarters, with the decline accelerating.

The full impact of the coronavirus is yet to play out. Economic activity in February and March is likely to be impacted directly and indirectly, depending on the duration and intensity of its spread.

Disruptions in supply chains and lower external demand may further add to domestic issues.

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