Facts in News

Facts in News

Few Electron Bubbles

Recently, scientists of the Indian Institute of Science (IISc) have experimentally shown the existence of two species of Few Electron Bubbles (FEBs) in superfluid helium for the first time. 

• FEBs are nanometre-sized cavities in liquid helium containing just a handful of free electrons.
  • An electron injected into a superfluid helium creates a Single Electron Bubble (SEB), a cavity that is free of helium atoms and contains only the electron.
  • There are also Multiple Electron Bubbles (MEBs) that contain thousands of electrons.
• The number, state and interactions between free electrons dictate the physical and chemical properties of materials.
• Creation Methodology
  • The researchers first applied a voltage pulse to a tungsten tip on the surface of liquid helium and then generated a pressure wave on the charged surface using an ultrasonic transducer.
  • This allowed them to create 8EBs and 6EBs, two species of FEBs containing eight and six electrons respectively.
  • These were found to be stable for at least 15 milliseconds (quantum changes typically happen at much shorter time scales) which would enable researchers to trap and study them. 
• Significance
  • FEBs can help scientists decipher phenomena like turbulent flows in superfluids and viscous fluids, or the flow of heat in superfluid helium.
    • Just like how current flows without resistance in superconducting materials at very low temperatures, superfluid helium also conducts heat efficiently at very low temperatures.
  • FEBs can serve as a useful model to study how the energy states of electrons and interactions between them in a material influence its properties.
  • Understanding the formation of FEBs can provide insights into the self-assembly of soft materials, which can be important for developing next-generation quantum materials.

(Image Courtesy: DTE)

Kármán Line

Recently, British businessman Richard Branson has given the official kickstart to space tourism, however, experts and space enthusiasts are in doubt whether the height to which he travelled can be termed ‘space’.

• The most widely accepted boundary of space is known as the Kármán line, 100km above mean sea level.
• Need
  • The 1967 Outer Space Treaty says that space should be accessible to all countries and can be freely and scientifically investigated.
  • Defining a legal boundary of what and where space is can help avoid disputes and keep track of space activities and human space travel.
• According to most experts, space starts at the point where orbital dynamic forces become more important than aerodynamic forces, or where the atmosphere alone is not enough to support a flying vessel at suborbital speeds.
  • The chemical composition of the atmosphere is largely constant up to the mesopause (boundary between mesosphere and thermosphere) so layers beyond that can reasonably be identified as ‘outer space’.
• In the 1900s, Hungarian physicist Theodore von Kármán determined the boundary to be around 50 miles up, or roughly 80 kms above mean sea level and the imaginary line was set up 100 kms above with his name.
• In 2004, test pilot Mike Melville became the first private astronaut to fly beyond the line.

(Image Courtesy: Twitter)

Senari Massacre of 1999

Recently, the Supreme Court (SC) has agreed to hear Bihar government’s appeal against the acquittal by Patna High Court of 14 accused in the Senari massacre.

• On 18^th March 1999, 34 upper caste men were forced out of their homes in Senari village of Jehanabad district allegedly by cadres of the now defunct Maoist Communist Centre (MCC) and slaughtered near the village temple.
  • The village now comes in Arwal district of Bihar.
• It was a sequel in the prolonged caste war between the MCC and private armies of upper caste villagers, especially the Ranbir Sena led by Barmeshwar Mukhiya, who was jailed in 2012.
• It was said to be a fallout of the Laxmanpur-Bathe massacre in which 57 Dalits were killed in 1997.
  • Of the 91 massacres between 1977 and 2000, 76 took place between 1990 and 2000, in which over 350 people were killed.
  • Districts of central Bihar such as Gaya, Jehanabad, Aurangabad and the Shahabad region of Bhojpur were the worst affected.
• In November 2016, a Jehanabad court sentenced 11 accused to death and awarded the life sentence to three others.
  • Three of those convicted challenged the verdict in the High Court.
• In May 2021, Patna High Court acquitted all 14 accused due to lack of sufficient corroborative evidence.
• The state government then prepared to present a strong case before the SC.

(Image Courtesy: IT)

Place in News: Cabo Delgado

The European Union has approved a Military Training Mission in Mozambique to support armed forces there to protect the civilian population. 

Aim: 

• To train and support the military in restoring security to northern Cabo Delgado, which has been plagued by extreme violence amid Jihadist attacks since 2017.
• It will involve military training, including operational preparation, specialised training in counter-terrorism and training and education in the protection of civilians. 
• Its mandate will initially last for two years.

Background:

• Over the last three years, more than 2,800 people have died in the violence which has forced about 9,00,000 others from their homes.
• Some provinces of Mozambique are under the grip of an Islamist terror group.

Cabo Delgado

• It is the northernmost province of Mozambique.
• As well as bordering the neighbouring country of Tanzania, it borders the provinces of Nampula and Niassa. 
• The region is an ethnic stronghold of the Makonde tribe, with the Makua and Mwani as leading ethnic minorities.

Right to Repair Movement

In recent years, countries around the world have been attempting to pass effective ‘right to repair’ laws.

About:

• Recently, US President Joe Biden signed an executive order calling on the Federal Trade Commission to curb restrictions imposed by manufacturers that limit consumers’ ability to repair their gadgets on their own terms.
• The UK too introduced a right-to-repair law that makes it easier for people to buy and repair everyday-use gadgets.

Right to Repair Movement

• The movement started sometime in the 1950s, at the beginning of the computer era.
• It advocates the rights of the consumer to be able to repair or fix their electronic gadgets.
• It aims to get tech companies to make tools, spare parts, and repair manuals accessible to the public. This can help consumers and repair shops fix devices and extend their lifespan. 

Opposition from Tech Giants

• Large tech companies, including Apple, Microsoft, Amazon and Tesla, have been lobbying against the right to repair.
• Reason: Opening up their intellectual property to third-party repair services or amateur repairers could lead to exploitation and impact the safety and security of their devices.
  • Also, this will put a hindrance to their sales as people will no longer have to ‘upgrade’ their devices every couple of years.
  • This could lead to more e-waste generation.

Space Rice

Recently, China harvested the 1st batch of seeds that travelled around the moon.

About

• Rice seeds exposed to the environment in Space may mutate and produce higher yields once planted on Earth. 
• China has been taking seeds of rice and other crops to Space since 1987. 
• Significance: 
  • It is aimed at boosting China’s grain harvest and thereby safeguarding the country’s food security.
  • It could test a self-recycling ecosystem in space, which will greatly cut costs and reduce the resources needed for future manned space flights.

Flash Floods

Recently, Dharamsala, the winter capital of Himachal Pradesh, has been hit by flash floods after heavy rains.

• Flash floods are a hydro-meteorological hazard.

Definition: 

• Flash floods are floods of short duration with a relatively high peak discharge usually less than 6 hours between the occurrence of rainfall and the peak flood.
• WMO defines flash flood as “A flood of short duration with a relatively high peak discharge”. 

Causative events: 

• Heavy rainfall and 
• Rainfall on saturated soils.

Effects:

• Impacts on built environment,
• Impacts on man-made mobile objects,
• Impacts on the natural environment (including vegetation, agriculture, geomorphology, and pollution) and
• Impacts on the human population (entrapments, injuries, fatalities). 

Issues:

• Flash floods are among the world?s deadliest natural disasters.
• Data from World Meteorological Organisation (WMO) suggests that across the world, about 5,000 people die annually due to flash floods.
• Despite such high mortality, there is no robust forecasting or warning system for flash floods.
• The flood situation worsens in the presence of choked drainage lines or encroachments obstructing the natural flow of water.

South Asian Flash Flood Guidance System (FFGS)

• The India Meteorological Department (IMD) launched the South Asian FFGS.
• It is aimed at helping disaster management teams.
• Helps governments make timely evacuation plans ahead of the actual event of flooding.