UPSC Essentials | Daily subject-wise quiz : Environment, Geography, Sci-Tech MCQs on A23 iceberg, T Coronae Borealis, Nankai Trough and more (Week 71)

Statement 1: The A23 iceberg is located near the South Orkney Islands, northeast of the Antarctic Peninsula.

Statement 2: Large Antarctic icebergs are designated by A, B, C and D depending on where in Antarctica they originate

Which one of the following is correct in respect of the above statements?

(a) Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation for Statement 1.

(b) Both Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation for Statement 1.

(c) Statement 1 is correct but Statement 2 is incorrect.

(d) Statement 1 is incorrect but Statement 2 is correct.

Explanation

— A23 iceberg is spinning near the South Orkney Islands, approximately 375 miles northeast of the Antarctic Peninsula, “maintaining a chill 15 degree rotation per day,” according to the British Antarctic Survey, the UK’s polar research institute, on social media. Hence, statement 1 is correct.

— A23, which was significantly larger than A23a, was one of three icebergs that calved off the Filchner Ice Shelf in 1986.

— Large Antarctic icebergs are identified as A, B, C, or D depending on where they originate, and they are assigned a number only when they reach a certain size. Hence, statement 2 is correct.

— The iceberg sits in Iceberg Alley, a prominent iceberg-spotting area in the Southern Ocean. Large icebergs typically move swiftly and are pulled by the Antarctic Circumpolar Current, the world’s greatest ocean current. The ice blocks are finally fired eastward into warmer waters, where they melt and dissolve. Brearley characterised the changeover as “a warm bath of water” with temperatures barely a few degrees above freezing.

Both Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation for Statement 1.

Therefore, option (b) is the correct answer.

QUESTION 2

With reference to the Polaris Dawn Mission, consider the following statements:

1. The mission will feature the first-ever private spacewalk.

2. Polaris Dawn will dock with the International Space Station (ISS).

3. The mission aims to conduct scientific experiments and test Starlink’s laser-based communications.

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

Explanation

— SpaceX plans to launch the breakthrough Polaris Dawn mission on August 26, marking a key milestone in private spaceflight.

— The mission is slated to launch from NASA’s Kennedy Space Centre in Florida on a Falcon 9 rocket.

— The mission will include the first private spacewalk and attempts to achieve the highest Earth orbit since the Apollo era. Hence, statement 1 is correct.

— Polaris Dawn will not dock with the International Space Station (ISS) but will operate as a free-flying mission in Earth orbit. Hence, statement 2 is not correct.

— The Polaris Dawn team is made up of four members: millionaire entrepreneur Jared Isaacman, who will lead the project; pilot Scott “Kidd” Poteet, a retired US Air Force lieutenant colonel; and mission specialists Sarah Gillis and Anna Menon, both SpaceX engineers.

Mission Objectives

(i) The first-ever private spacewalk.

(ii) Reaching an altitude of approximately 700 kilometers, the highest for a crewed mission since the Apollo era.

(iii) Testing SpaceX’s newly designed extravehicular activity (EVA) spacesuits in space.

(iv) Conducting scientific experiments and testing Starlink’s laser-based communications. Hence, statement 3 is correct.

— The crew will ascend to an altitude of almost 700 kilometres, making this the farthest crewed mission from Earth since the Apollo program.

Therefore, option (b) is the correct answer.

QUESTION 3

With reference to the landslides in India, consider the following statements:

1. In the Himalayan states, Uttarakhand has the largest landslide-prone land area.

2. Outside the Himalayan states, Karnataka is the most vulnerable state.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

Explanation

— Landslides have occurred all over the world this year, from Yunnan in China in January to Papua New Guinea in May, which killed over 2,000 people, to Sulawesi Island in Indonesia and Wayanad in Kerala in July.

— Landslides are natural occurrences that typically occur in hilly areas with steep slopes. During a landslip, vast volumes of rock, boulders, loose mud, dirt, and debris tumble down slopes and hillsides, gaining pace and frequently carrying vegetation or buildings with them.

— According to a team from IIT-Madras that has studied the phenomena, India contributes to around 8% of global landslide fatalities, with 847 dead and thousands displaced between 2001 and 21.

— According to a report published in IIT-M’s Shaastra magazine, the ILSM indicates that 13.17% of the country is prone to landslides, which is higher than previously thought. Furthermore, 4.75% of the area is deemed “very highly susceptible”.

— “Sikkim has the largest land area (57.6%) prone to landslides, whereas Kerala is the most vulnerable state outside of the Himalayas, with more than 14% of its land mass classified as “extremely high vulnerability.” Hence, statements 1 and 2 are not correct.

Therefore, option (d) is the correct answer.

QUESTION 4

T Coronae Borealis was recently in the news. It is a:

(a) Binary Star System

(b) Brown Dwarf

(c) Centaurs

(d) Elliptical Galaxy

Explanation

— The world is about to see a rare nova explosion, a tremendous increase in the brightness of a star triggered by a thermonuclear explosion on the surface of a dwarf star.

— T Coronae Borealis, often known as the Blaze Star or T CrB, is a binary system in the Northern Crown. This system contains the remains of a dead star the size of Earth, with a mass comparable to the Sun. The T CrB is simply a white dwarf and a red giant planet orbiting each other.

— According to NASA, the T Coronae Borealis lives in the constellation Coronae Borealis. Because of its periodic explosive nature, scientists on Earth have been attentively monitoring this star system for many years. It has been classed as a recurrent nova due to its repeated outbursts.

— It is a binary system, which means the T CrB is made up of two stars: a red giant and a white dwarf. Both of these stars orbit each other, creating ideal conditions for periodic nova outbursts. The T CrB has a thermonuclear detonation on its surface roughly every 80 years. It was last observed from Earth in 1946.

Therefore, option (a) is the correct answer.

QUESTION 5

The Nankai Trough is an underwater subduction zone where:

(a) African Plate collides with the Philippine Sea Plate

(b) South American Plate collides with the African Plate

(c) Eurasian Plate collides with the Philippine Sea Plate

(d) Eurasian Plate collides with the Scotia Plate

Explanation

— After a 7.1-magnitude earthquake shook southern Japan, the country’s meteorological agency issued its first-ever “megaquake advisory”.

— The Nankai Trough, a subduction zone (where tectonic plates meet and the heavier one slips under another) along Japan’s southwest Pacific coast, is expected to experience worse shaking and larger tsunamis than usual, according to the warning.

— The Nankai Trough is a nearly 900-kilometer-long undersea subduction zone formed when the Eurasian Plate collides with the Philippine Sea Plate, driving the latter under the former and into the Earth’s mantle.

— This accumulates tectonic stress, which can result in a megaquake — an earthquake with a magnitude greater than 8.

Therefore, option (c) is the correct answer.

Previous Daily Subject-Wise-Quiz

Daily subject-wise quiz — Polity and Governance (Week 71)

Daily Subject-wise quiz — History, Culture, and Social Issues (Week 71)

Daily subject-wise quiz — Environment, Geography, Science and Technology (Week 70)

Daily subject-wise quiz — Economy (Week 70)

Daily subject-wise quiz – International Relations (Week 70)

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