2nd September 2025

Explanation – Mira variables are a type of giant star that go through regular cycles of expanding and contracting. These cycles cause their brightness to vary in a predictable way, typically over periods ranging from 100 to 1,000 days. These stars are relatively cool, with surface temperatures around 3,000 Kelvin (about half the temperature of the Sun's surface), and they are in the late stages of their life. There is a strong relationship between how bright they are and how long their pulsation cycles last. This relationship allows astronomers to use them as "standard candles" to measure distances in the universe. 

Explanation – Bordeaux mixture is a bactericide and fungicide made by mixing copper sulfate and lime (calcium hydroxide) with water. It has a low aqueous solubility and is not volatile. It persists in rainy weather and can provide long-lasting protection against diseases. Bordeaux mixture is usually applied after harvest, before rainy weather starts. However, applying Bordeaux mixture to newly growing leaves can cause injury to the new growth. 

Explanation – Ramon Magsaysay award is named after Ramon Magsaysay, the third president (1953-57) of Philippines. It is given to individuals and organisations in Asia regardless of race, creed, sex, or nationality, who have achieved distinction in their respective fields. There are some instances where the winners came from Non-Asian countries, but accomplished something in Asia. 

Explanation – Government provides fertilisers, Urea and 22 grades of P&K fertilisers to farmers at subsidised prices through fertiliser manufacturers/importers. The subsidy on P&K fertilisers is being governed by NBS Scheme from 2010. It is being implemented from April 2010 by the Department of Fertilisers, Ministry of Chemicals & Fertilisers. Under NBS, a fixed amount of subsidy decided on an annual basis, is provided on each grade of subsidised Phosphatic & Potassic (P&K) fertilisers depending on its nutrient content. 

Explanation – The Green Credit Programme launched by India at COP28 aims to incentivise various environmentally positive actions (eight identified so far) through tradable credits. The programme goes beyond just afforestation and focuses on areas like sustainable agriculture, waste management, and water conservation. The Indian Council of Forestry Research and Education (ICFRE) is responsible for implementation, not ICAR.