Topic 1: Matangini Hazra and Kanaklata Barua
Context: During her address to the nation on the eve of Independence Day, President of India paid tributes to women freedom fighters.
- She was born in a village named Hogla, near Tamluk, West Bengal in 1869.
- Matangini was the daughter of a poor farmer who could not afford to provide her a formal education.
- With no means to raise a decent dowry, she found herself married at 12 and was widowed at 18.
- Matangani’s love for Gandhi was so great that she became known in our village as Gandhiburi, the old Gandhian woman.
- At the age of 61, she was arrested for taking part in the Civil Disobedience Movement in 1930 and the Salt March led by Gandhi.
- She became an active member of the Indian National Congress and started spinning her own khadi in Gandhi’s footsteps.
- Her involvement with the freedom struggle intensified during the Quit India Movement launched by Gandhi in August 1942.
- In September that year, a 73-year-old Hazra led a large procession of around 6,000 protesters, mostly women.
- The procession marched with the aim to take over the Tamluk police station from British authorities.
- British police personnel shot at her thrice.
- She collapsed and died, chanting ‘Vande Mataram’.
- In 1977, the first statue in the Kolkata Maidan dedicated to a woman revolutionary was that of Matangini Hazra.
- One of the youngest martyrs of the Quit India Movement, Kanaklata Barua has an iconic status in Assam.
- Barua led the Mrityu Bahini, a procession of freedom fighters, to unfurl the Tricolour at Gohpur police station on September 20, 1942.
- When police did not let them move forward, an altercation led to firing, killing Barua at the head of the procession.
- The squad strictly admitted members aged 18 and above but Kanaklata was an exception.
Topic 2: Cloudburst
Context: Following heavy rains in Himachal Pradesh, landslides have occurred in the state.
About a cloudburst
- A cloudburst is a localised but intense rainfall activity.
- While it can also occur in plains, the phenomenon is most common in hilly regions.
- Not all instances of very heavy rainfall, however, are cloudbursts.
- A cloudburst has a very specific definition:
- Rainfall of 10 cm or more in an hour over a roughly 10 km x 10 km area is classified as a cloudburst event.
- By this definition, 5 cm of rainfall in a half-hour period over the same area would also be categorised as a cloudburst.
- Average rainfall in India:
- In a normal year, India, as a whole, receives about 116 cm of rainfall over the entire year.
- This means if the entire rainfall everywhere in India during a year was spread evenly over its area, the total accumulated water would be 116 cm high.
- There are huge geographical variations in rainfall within the country, and some areas receive over 10 times more than that amount in a year.
- But on average, any place in India can be expected to receive about 116 cm of rain in a year.
- Cloudburst vs average rainfall:
- During a cloudburst event, a place receives about 10% of this annual rainfall within an hour.
How common are cloudbursts?
- Cloudbursts are not uncommon events, particularly during the monsoon months.
- Most of these happen in the Himalayan states where the local topology, wind systems, and temperature gradients between the lower and upper atmosphere facilitate the occurrence of such events.
- These events are highly localized.
- They take place in very small areas which are often devoid of rainfall-measuring instruments.
- The consequences of these events, however, are not confined to small areas.
- Because of the nature of the terrain, the heavy rainfall events often trigger landslides and flash floods, causing extensive destruction downstream.
- This is the reason why every sudden downpour that leads to the destruction of life and property in the hilly areas gets described as a “cloudburst”, irrespective of whether the amount of rainfall meets the defining criteria.
Can cloudbursts be forecast?
- The Indian Metrological Department forecasts rainfall events well in advance, but it does not predict the quantum of rainfall.
- The forecasts can be about light, heavy, or very heavy rainfall, but weather scientists do not have the capability to predict exactly how much rain is likely to fall at any given place.
- The forecasts are for a relatively large geographical area, at best at a district level.
- As they zoom in over smaller areas, the forecasts get more and more uncertain.
- Specific cloudburst events cannot be forecast.
Topic 3: Aditya-L1 mission
Context: The Indian Space Research Organisation (Isro) released images of the Aditya-L1 mission.
About the Aditya-L1 mission
- The Aditya-L1 will observe the Sun from a close distance, and try to obtain information about its atmosphere and magnetic field.
- It’s equipped with seven payloads (instruments) on board to study the Sun’s corona, solar emissions, solar winds and flares, and Coronal Mass Ejections (CMEs), and will carry out round-the-clock imaging of the Sun.
- Aditya L1 will perform continuous observations looking directly at the Sun.
Significance of studying the Sun
- The solar weather and environment affect the weather of the entire solar system.
- Variations in this weather can change the orbits of satellites or shorten their lives, interfere with or damage onboard electronics, and cause power blackouts and other disturbances on Earth.
- Knowledge of solar events is key to understanding space weather.
- To learn about and track Earth-directed storms, and to predict their impact, continuous solar observations are needed.
- Every storm that emerges from the Sun and heads towards Earth passes through L1, and a satellite placed in the halo orbit around L1 of the Sun-Earth system has the major advantage of continuously viewing the Sun without any occultation/eclipses.
- L1 refers to Lagrangian/Lagrange Point 1, one of five points in the orbital plane of the Earth-Sun system.
- Lagrange Points, named after Italian-French mathematician Josephy-Louis Lagrange, are positions in space where the gravitational forces of a two-body system (like the Sun and the Earth) produce enhanced regions of attraction and repulsion.
- These can be used by spacecraft to reduce fuel consumption needed to remain in position.
- The L1 point is home to the Solar and Heliospheric Observatory Satellite (SOHO), an international collaboration project of NASA and the European Space Agency (ESA).
- The L1 point is about 1.5 million km from Earth, or about one-hundredth of the way to the Sun.