Prelim Snippets- 31-12-2019
1. Sun’s Corona
Why in News?
- Solar physicists from Centre for Excellence in Space Sciences (CESSI), IISER Kolkata, have succeeded in predicting the shape of Sun’s corona at the time of the Recent Annular Eclipse.
- The corona is the outermost part of the Sun’s atmosphere. It is the aura of plasma that surrounds the Sun and other stars.
- The Sun’s corona extends millions of kilometres into outer space and is most easily seen during a total solar eclipse, but it is also observable with a coronagraph.
- Spectroscopy measurements indicate strong ionization in the corona and a plasma temperature in excess of 1000000 Kelvin much hotter than the surface of the Sun.
- The Predictive Solar Surface Flux Transport model developed by the CESSI team can predict the shape of the corona well in advance.
- The researchers can predict the large-scale structure of the Sun’s corona up to two months in advance.
- This model gives advance knowledge and a large window of preparedness for space weather driven by Coronal Magnetic Fields.
- The dynamic events on the Sun can affect Earth’s outer atmosphere and our technologies, leading to disruption in communication and navigation networks (GPS).
- These are more frequent during solar maxima and pose a threat to space reliant Technology and Astronauts.
2. Drake Passage
Why in News?
- In a first, six rowers from four countries crossed the Drake Passage, in just under two weeks setting up a new Guinness World Records (GWR).
- Last year, an all-woman Indian Navy team on Indian Naval Sailing Vessel (INSV) Tarini had also successfully crossed Passage.
- The Passage is located between Cape Horn at the tip of South America and the Antarctic Peninsula.
- It is named after Sir Francis Drake, who was the first Englishman to circumnavigate the globe.
- It has an average depth of about 11,000 feet, with deeper regions going up to over 15,600 feet near the northern and southern boundaries.
- The Drake Passage is considered one of the roughest waterways in the world because here, layers of cold seawater from the south and warm seawater from the north collide to form powerful eddies.
- This eddies when combined with strong winds and storms can be treacherous for those attempting to navigate it.
- It is also the narrowest stretch in the Southern Ocean and spans approximately 800 km between the southern tip of South America and the northern tip of the West Antarctic Peninsula.
- The waters of the passage are highly turbulent, unpredictable, and frequented by icebergs and sea ice.
3. Winged visitors flock to Pulicat, with birdwatchers in tow
Why in News?
- The annual flamingo festival in Nellore district is round the corner with the winged visitors arriving in large numbers on their annual sojourn.
- The Flamingo Festival is organised annually to encourage tourism in Pulicat and Nellapattu, Andhra Pradesh.
- Located near Pulicat Lake on the Andhra Pradesh-Tamil Nadu border, Nelapattu Bird Sanctuary is one of the biggest habitats for pelicans and other birds.
- Pulicat Lake is the second largest brackish water lake or lagoon in India, after Chilika Lake.
- It straddles the border of Andhra Pradesh and Tamil Nadu states with over 96% of it in Andhra Pradesh and 4% in Tamil Nadu, situated on the Coromandal Coast in South India.
- The barrier island of Sriharikota separates the lake from the Bay of Bengal.
- Two rivers which feed the lagoon are the Arani riverat the southern tip and the Kalangi River from the northwest, in addition to some smaller streams.
- The lake encompasses the Pulicat Lake Bird Sanctuary. Pulicat Lake Bird Sanctuary and Nelapattu Bird Sanctuary are two most popular bird sanctuaries in South India and an important breeding site for spot billed pelicans in India and noted for the many greater flamingos.
- Flamingos are large birds that are identifiable by their long necks, sticklike legs and pink or reddish feathers.
- According to the Integrated Taxonomic Information System (ITIS), there are six species of flamingo: Greater flamingo (tallest species), Lesser flamingo, Chilean flamingo, Andean flamingo, James’ (or puna) flamingo and American (or Caribbean) flamingo.
- Indian subcontinent is the largest breeding ground for Greater flamingo and lesser flamingo during every winter season.
- Flamingos animals are very social and they thrive on interaction with each other.
- Flamingos mouth is like a strainer which helps keep the food in and spits the water out.
- They can stand on one leg comfortably and can even sleep in this position.
- The bright colour of flamingo feathers is caused by the presence of beta carotenoid found in the algae and crustaceans that make up the diet of a flamingo.
4. Belum Caves
- Located near Kurnool in Andhra Pradesh, Belum Caves is the largest and longest cave system open to the public on the Indian subcontinent.
- These caves, which get their name from the Sanskrit word bilum (hole), were formed by the action of water flowing on limestone deposits over millions of years.
- They are known for its speleothems (mineral deposits formed in a cave), such as stalactite and stalagmite formations.
- Though these caves were known to the locals for thousands of years, the first official records that mention them are from 1884, by Robert Bruce Foote, who conducted surveys for the Geological Survey of India.
- In 2013, a new cavernicolous species (inhabiting caves) named Andhracoides gebaueri was discovered at the Belum caves.
- Jains and Buddhists monks occupied these caves centuries ago. Many Buddhists relics were found inside the caves.
Stalactite & Stalagmite:
- A stalactite is a type of formation that hangs from the ceiling of caves, hot springs, or manmade structures such as bridges and mines.
- A stalagmite is a type of rock formation that rises from the floor of a cave due to the accumulation of material deposited on the floor from ceiling drippings.
5. World Economic League Table
Why in News?
- Recently, World Economic League Table 2020 was released by Centre for Economics and Business Research (CEBR).
- It is an annual calculation by CEBR jointly published by CEBR and Global Construction Perspectives. The base data for 2019 is taken from the IMF World Economic Outlook.
Key Findings of the Report:
- India will overtake Germany to become fourth-largest economy in the world by the year 2026.
- According to a report India is all set to overtake Japan to become the third-largest economy by 2034 and to become a 5 trillion-dollar economy by 2026, 2 years later than the government’s target of 2024.
- India is decisively overtaken both France and the UK to become the world’s fifth-largest economy in 2019.
- The report said that Japan, Germany and India will battle for third position over the next 15 years.
//php comments_template(); ?>