[DAY 5] 60 DAY RAPID REVISION (RaRe) SERIES for UPSC Prelims 2023 – SCIENCE AND TECHNOLOGY, CURRENT AFFAIRS & CSAT TEST SERIES!

Solution (c)

Explanation:

• Exoplanets are planetsthat orbit other stars and are beyond our solar system. They come in a host of different sizes. They can be gas giants bigger than Jupiter or as small and rocky as Earth. They are also known to have different kinds of temperatures from boiling hot to freezing cold. Hence, statement 1 is correct.
• LHS 475 b is a new terrestrial rocky exoplanet discovered by the National Aeronautics and Space Administration (NASA). It is roughly the same size as Earth, its diameter is 99% the same as Earth.LHS 475 b is about 41 light-years away from Earth in the constellation Octans and differs from the Earth in that it completes an orbit in just two days and is hundreds of degrees hotter than Earth.According to NASA, more than 5,000 exoplanets have been discovered. Hence, statement 2 is incorrect.
• Exoplanets cannot be seen directly through telescopes from the Earth because they are hidden by the bright glare of the stars they orbit. So scientists rely on indirect methods, such as the transit method, which is measuring the dimming of a star that happens to have a planet pass in front of it, and gravitational microlensing in which light from a distant star is bent and focused by gravity as a planet passes between the star and Earth. Hence, statement 3 is correct.
• The study of exoplanets helps in determining the habitable zone of the discovered space and helps us piece together information about our planetary system and origin. Hence, statement 4 is correct.

Solution (b)

Explanation:

• The Lower Earth Orbit is an orbit around the earth with an altitude between 160 – 2000 km. the satellites placed in LEO can have a titled plane and the majority of human space flights land in LEO. Hence, statement 1 is incorrect.
• Unlike geosynchronous satellite, satellites in LEO have a small field of view and so can observe and communicate with only a fraction of the Earth at a time. That means that a network (or “constellation”) of satellites is required to provide continuous coverage. Satellites in lower regions of LEO also suffer from fast orbital decay and require either periodic re-boosting to maintain a stable orbit or launching replacement satellites when old ones re-enter. Hence, statement 2 is correct.
• It has applications in the field of satellite imaging, communication satellites, remote-sensing satellites, and earth-observing satellites. The International Space Station is located in LEO. Hence, statement 3 is correct.

Solution (b)

Explanation:

• Space debrisrefers to man-made objects in Earth’s orbit that no longer serve a useful purpose. This includes defunct satellites, spent rocket stages, and fragments of debris from collisions or other events. Of known and tracked space junk 70 percent is in low-Earth orbit, which extends about 1,250 miles (2,000 km) above the Earth’s surface. Hence, statement 1 is correct.
• Project NETRA is an early warning system in spacelaunched by the Indian Space Research Organisation (ISRO) to detect debris and other hazards to Indian satellites.

ISRO has also set up a Centre for Space Debris Research to monitor and mitigate the threat of space debris and the System for Safe and Sustainable Operations Management (IS 4 OM) to continually monitor objects posing collision threats, predict the evolution of space debris, and mitigate the risk posed by space debris. Hence, statement 2 is correct.

• The Kessler syndrome (also called the Kessler effect,[1][2] collisional cascading, or ablation cascade), proposed by NASA scientist Donald J. Kessler in 1978, is a scenario in which the density of objects in low Earth orbit (LEO) due to space pollution is high enough that collisions between objects could cause a cascade in which each collision generates space debris that increases the likelihood of further collisions. Hence, statement 3 is incorrect.
• The European Space Agency has launched the Clean Space initiative,aimed at reducing the amount of space debris.Hence, statement 4 is correct.

Solution (d)

Explanation:

• Communication Satellite is an artificial satellite that is placed in the earth’s orbit to send and receive communication data between a source and a destination. They are mostly placed in High-Earth Orbit. These satellites support telecommunication. Telecasting, phone calls, internet connectivity, radio, and much remote connectivity are typical applications. Hence, statement 1 is incorrect.
• They use microwaves and radiowaves for transmitting signals. Hence, statement 2 is correct.
• Communications satellites are often in geostationary orbit. At the high orbital altitude of 35,800 kilometers, a geostationary satellite orbits the Earth in the same amount of time it takes the Earth to revolve once. From Earth, therefore, the satellite appears to be stationary, always above the same area of the Earth. The area to which it can transmit is called a satellite’s footprint. Hence, statement 3 is correct.

Solution (d)

Explanation:

• A Dark Sky Reserve is a designation given to a place that has policies in place to ensure that a tract of land or region has minimal artificial light interference.It is a public or private land of substantial size that possess an exceptional quality of starry nights that is specifically protected for its scientific, natural, educational, cultural heritage, and public enjoyment. Hence, statement 1 is correct.
• India’s first dark sky reserve, the Indian Astronomical Observatory (IAO) is located in Hanle, Ladakh. Hanle is one of the world’s highest-located sites for optical, infrared, and gamma-ray telescopes. Hence, statement 2 is correct.
• Indian Astronomical Observatory is situated at an altitude of 4500 meters atop Mt. Saraswati in the vast Nilamkhul Plain in the Hanle Valley of Changthang.The site is a dry, cold desert with a sparse human population and the ancient Hanle monastery is its nearest neighbor.It has the advantages of more clear nights, minimal light pollution, background aerosol concentration, extremely dry atmospheric conditions, and uninterrupted monsoon. Such conditions are considered crucial for astronomers to build huge telescopes and plan for future observatories and predict how they will vary with time.
• Himalayan Chandra Telescope (HCT) is an optical-infrared telescope located at IAO. Also GROWTH-India Telescope is the country’s first fully robotic research telescope located at IAO.Hence, statement 3 is correct.
• The International Dark Sky Association is a U.S.-based non-profit organisation that designates places as International Dark Sky Places, Parks, Sanctuaries and Reserves, depending on the criteria they meet. Several such reserves exists around the world but none so far in India.(Before Hanle). Hence, statement 4 is correct.

Solution (a)

Explanation:

• The National Aeronautics and Space Administration (NASA) is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research. It was established under the National Aeronautics and Space Act of 1958 and is headquartered in Washington, DC, USA
• Artemis I is an uncrewed space mission to the moon. Hence, statement 1 is incorrect.
• Perseverance Rover is a space mission to Mars. Hence, statement 2 is correct.
• Messenger is a space mission to Mercury. Hence, statement 3 is incorrect.
• Mariner 2 is a space mission to Venus. Hence, statement 4 is incorrect.

Solution (a)

Explanation:

• Small Satellite Launch Vehicles (SSLV) are specially designed to carry smaller commercial satellites into low-earth orbit (LEO)from 200-2,000 km above the Earth’s surface. Hence, statement 1 is correct.
• It is a three-stage Launch Vehicle and can carry a payload capacity of up to 500 kg. Hence, statement 2 is correct.
• Nanosatellites, micro, and minisatellites can be launched through SSLV.Hence, statement 3 is incorrect.

Solution (c)

Explanation:

• Laser Interferometer Gravitational-Wave Observatory (LIGO) project is an observatory for detecting cosmic gravitational waves and for carrying out experiments in astronomical studies. Hence, statement 1 is correct.
• The LIGO project operates three gravitational-wave (GW) detectors among which two are at Hanford, Washington, and one is at Livingston in Louisiana. Hence, statement 2 is correct.
• The LIGO concept built upon early work by many scientists to test a component of Albert Einstein’s theory of general relativity. Hence, statement 3 is incorrect.

Solution (d)

Explanation:

• Neutrinos are the second most abundant particles in the Universe after photons. They are produced in the cores of stars. Hence, statement 1 is incorrect.
• Every time atomic nuclei come together (like in the sun) or break apart (like in a nuclear reactor), they produce neutrinos. Even a banana emits neutrinos—they come from the natural radioactivity of the potassium in the fruit. Hence, statement 2 is correct.
• The study of neutrinos helps in studying the origin of the universe by understanding the oscillations of neutrinos and their relations with mass. Hence, statement 3 is correct.

Solution (b)

Explanation:

• Dark matter is made up of particles that do not interact through electromagnetic interactions i.e. they do not have any charge. So, these are dark particles, namely because they do not emit light, which is an electromagnetic phenomenon, and matter because they possess mass like normal matter and hence interact through gravity.Dark energy is an unknown form of energy that affects the universe on the largest scales.The first observational evidence for its existence came from measurements of supernovae, which showed that the universe does not expand at a constant rate and rather, the expansion of the universe is accelerating. Hence, statement 1 is correct.
• The universe is made of about 27% dark matter and 68% dark energy. Hence, statement 2 is incorrect.
• While dark matter attracts and holds galaxies together, dark energy repels and causes the expansion of the universe. Hence, statement 3 is correct.

Note: Despite both components being invisible, we know a lot more about dark matter, since its existence was suggested as early as the 1920s, while dark energy wasn’t discovered until 1998.

Solution (c)

Explanation:

• The cosmic microwave background (CMB) is a faint cosmic background radiation filling all space that dates back to about 400,000 years after the Big Bang. The CMB is useful to scientists because it helps us learn how the early universe was formed. It is at a uniform temperature with only small fluctuations visible. By studying these fluctuations, cosmologists can learn about the origin of galaxies. Hence, statement 1 is correct.
• Today, the CMB radiation is very cold, only 2.725° above absolute zero, thus this radiation shines primarily in the microwave portion of the electromagnetic spectrum, and is invisible to the naked eye.Hence, statement 2 is incorrect.
• CMB-Bharat is a proposal for comprehensive next-generation Cosmic Microwave Background (CMB) mission in international collaboration with major Indian contributions to revealing the first clear sign of quantum gravity in the very early universe. Hence, statement 3 is correct.

Solution (d)

Explanation:

• The Large Hadron Collider is a giant, complex machine built to study particles that are the smallest known building blocks of all things. It is the world’s most powerful particle collider. Hence, statement 1 is correct.
• In its operational state, it fires two beams of protonsalmost at the speed of light in opposite directions inside a ring of superconducting electromagnets. The magnetic field created by the superconducting electromagnets keeps the protons in a tight beam and guides them along the way as they travel through beam pipes and finally collide.
• Just before the collision, another type of magnet is used to ‘squeeze’ the particles closer together to increase the chances of collisions.  The particles are so tiny that the task of making them collide is akin to firing two needles 10 km apart with such precision that they meet halfway. Hence, statement 2 is incorrect.
• ATLASis the largest general-purpose particle detector experiment at the LHC. Hence, statement 3 is correct.
• In the LHC’s first run, the Higgs boson was discovered. The Higgs boson is the fundamental particle associated with the Higgs field, a field that gives mass to other fundamental particles such as electrons and quarks. Hence, statement 4 is correct.

Solution (b)

Explanation:

• The Hyperspectral Imaging Satellite (HysIS) was launched by the Indian Space Research Organisation. Hence, statement 1 is incorrect.
• Its primary goal is to study the Earth’s surface in visible, near-infrared, and shortwave infrared regionsof the electromagnetic spectrum. It can see in 55 spectral or colour bands from 630 km above the ground. Hyperspectral imaging allows the distinct identification of objects, materials, or processes on Earth by reading the spectrum for each pixel of a scene from space. It can be highly useful in marking out a suspect object or person and separating it from the background. This could aid in detecting transborder or other stealthy movements. Hence, statement 2 is correct.

Solution (c)

Explanation:

Tycho is a Type Ia supernova, which occurs when a white dwarf star shreds its companion star, triggering an explosion and sending debris hurtling into space at tremendous speeds. It released as much energy as the Sun would emit over ten billion years and blasted particles out into space near the speed of light. Hence, option c is correct.

Note:  Imaging X-ray Polarimetry Explorer (IXPE) Space Observatory is a joint effort of NASA and the Italian Space Agency. It studies the most extreme and mysterious objects in the universe – supernova remnants, supermassive black holes, and dozens of other high-energy objects.

Solution (a)

Explanation:

• The Atacama Large Millimetre/submillimetre Array (ALMA) Telescope is a state-of-the-art radio telescopethat studies celestial objects at millimeter and submillimetre wavelengths. they can penetrate through dust clouds and help astronomers examine dim and distant galaxies and stars out there. Ex: In 2015, the ALMA telescope helped scientists observe the Einstein ring phenomenon. Hence, statement 1 is correct.
• ALMA is an international partnership of the European Southern Observatory (ESO), the S. National Science Foundation (NSF), and the National Institutes of Natural Sciences (NINS) of Japan, together with NRC (Canada), MOST, and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. Hence, statement 2 is incorrect.

Solution (c)

Explanation:

The question asks for “incorrect code”

• Meteoroids are objects in space that range in size from dust grains to small asteroids and when they enter the Earth’s atmosphere, they are called a meteor. Hence, statement 1 is incorrect.
• If a meteoroid enters the Earth’s atmosphere and hits the ground, it is called a meteorite. Hence, statement 2 is incorrect.

Note: Aubrite meteorite was recently in news , is a coarse-grained igneous rock that formed in oxygen-poor conditions and contains exotic minerals not found on Earth.

Solution (b)

Explanation:

• Aditya-L1 Mission is India’s first solar mission. Hence, statement 1 is incorrect.
• It will study the Sun’s corona, photosphere, chromosphere, solar emissions, solar winds and flares, and Coronal Mass Ejections (CMEs). It will carry out round-the-clock imaging of the Sun. Hence, statement 2 is correct.
• It will be launched using the Polar Satellite Launch Vehicle (PSLV)with seven payloads. They are –
• Visible Line Emission Coronagraph (VELC)
• Solar Ultraviolet Imaging Telescope (SUIT)
• Solar Low Energy X-ray Spectrometer (SoLEXS)
• Aditya Solar wind Particle Experiment (ASPEX)
• High Energy L1 Orbiting X-ray Spectrometer (HEL1OS)
• Plasma Analyser Package for Aditya (PAPA)
• Advanced Tri-axial High-Resolution Digital Magnetometers

Hence, statement 3 is incorrect.

Solution (c)

Explanation:

• The Local Bubble is a large, low-density region in the interstellar medium (ISM) of our galaxy, the Milky Way. It’s a 1,000-light-year-wide cavity that is thought to have been created by a series of supernovae explosions that occurred about 30 to 50 million years ago. Hence, statement 1 is correct.
• It’s a cavity that is thought to have been created by a series of supernovae explosions that occurred about 30 to 50 million years ago. A supernova is a powerful and luminous explosion that occurs at the end of the life of a massive star. It is caused by the collapse of the core of the star, which can trigger a massive release of energy and are important for the enrichment of the interstellar medium with heavy elements and for the propagation of cosmic rays. Hence, statement 2 is correct.

Solution (b)

Explanation:

• The Kuiper Belt is a region of the solar system thatexists beyond the eight major planets, extending from the orbit of Neptune. Hence, statement 1 is incorrect.
• The Asteroid Belt has the maximum number of known asteroids and is found between Mars and Jupiter in the solar system. Hence, statement 2 is correct.

Solution (a)

Explanation:

• The Indian Data Relay Satellite System (IDRSS) helps to track and be constantly in touch with Indian satellites, in particular those in low-earth orbits. It is an Indian geostationary data relay satellite system consisting of two geostationary satellites. IDRSS will facilitate the relay of information between various Indian spacecraft, in-flight launch vehicle monitoring, and assist Indian Human Spaceflight Programme. Hence, statement 1 is correct .
• Currently, the US, Russia, China, and Europe have their data relay satellites. Hence, statement 2 is incorrect.

Solution(c)

• NCR Geo-portal (PARIMAN) is a robust system to facilitate better sub-regional and local planning. This contains various layers collected from authentic sources. The portal has many Base Maps, Satellite Image services and Night Light Data of different time spans.
• The Portal consists of around 179 Layers presented as Line, Point & Polygon feature covering details of various sectors like Land Use, Transport, Industries, Water, Power, Health, Shelter, Heritage & Tourism, Disaster Management, etc.

Solution(b)

Explanation:

• Statement 1 – Incorrect, The red panda is largely herbivorous and feeds primarily on bamboo. It also feeds on fruits, blossoms, acorns, eggs, birds and small mammals. Bamboo leaves may be the most abundant food item year-round and the only food they can access during winter
• Statement 2 – Correct, Adult pandas are generally solitary and territorial. The red panda appears to be both nocturnal and crepuscular, sleeping in between periods of activity at night.
• Statement 3 – Incorrect, The IUCN status of red pandas is ‘Endangered’

Solution (c)

Explanation:

• Statement 1 – Correct, An oncolytic virus is a virus that preferentially infects and kills cancer cells. As the infected cancer cells are destroyed by oncolysis, they release new infectious virus particles or virions to help destroy the remaining tumour.
• Statement 2 – Correct, A number of viruses including adenovirus, reovirus, measles, herpes simplex, Newcastle disease virus, and vaccinia have been clinically tested as oncolytic agents. Most current oncolytic viruses are engineered for tumour selectivity, although there are naturally occurring examples such as reovirus and the senecavirus resulting in clinical trials

Solution (d)

Explanation:

• Statement 1 – Incorrect, The NITI Aayog in collaboration with the Institute for Competitiveness developed benchmark for the innovation ecosystem among Indian States and Union territories.
• Statement 2 – Incorrect, Indicators used for ranking are :-
• *Five Enablers pillars ( Human capital , Investment, Knowledge worker, Business Environment, Safety and Legal Environment)
• *Two Performance Pillars (Knowledge Output, Knowledge Diffusion).

Solution (a)

Explanation:

• Statement 1 – Correct, The Bill also proposed to set-up Indian Antarctic Authority (IAA) under the Ministry of Earth Sciences, which shall be the apex decision making authority and shall facilitate programmes and activities permitted under the Bill.
• Statement 2 – Correct, A total of fifty-four State Parties to the Treaty, but twenty-nine countries have the status of Consultative Party with a right to vote in the Antarctic Consultative Meetings and twenty-five countries are Non-Consultative Parties having no right to vote. India signed the Antarctic Treaty on the 19th August, 1983 and received the consultative status on the 12th September, 1983.
• Statement 3 – Incorrect, The bill is in pursuant to India’s accession to Antarctic Treaty, the Protocol on Environment Protection (Madrid Protocol) to the Antarctic Treaty and to the Convention on the Conservation of Antarctic Marine Living Resources.

Solution (b)

Explanation:

Let number of boys = b

Number of girls = g

Then, b = 8+g = 5(b – g)[ b – g = 8 from given equation]

• b = 5 x 8

b = 40

Solution (c)

Explanation:

5 men and 4 women are to be seated in a row such that the women occupy the even places.

The 5 men can be seated in 5! Ways.

The 4 women can be seated only at the cross marked places (so that women occupy the

even places).

M×M×M×M×M

Therefore, the women can be seated in 4! Ways.

Hence, possible number of arrangements = 4! × 5! = 24 × 120 = 2880

Solution (c)

Explanation:

This is nothing but the number of ways of having a, b, c such that a + b + c = 11, where a, b, c

are natural numbers.

By having them to be natural numbers, we ensure that no box can be

empty. (No zeroes)

The question is similar to the previous one. 10C2 = 45 ways

Solution (b)

Explanation:

1 male out of 5 males can be selected in 5C1 ways

Similarly 1 female out of 3 can be selected in 3C1 ways

Since Ms Abhishek refuses to be in the committee which has Mr Bharath, the possible ways

so that a committee can be constituted is 5C 1 × 3C 1 – 1 = 5 × 3 – 1 = 14

Solution (c)

Explanation:

In the first paragraph, the author introduces the main idea. The author says, “Making the

perfect pizza can be complicated, but there are lots of ways for you to make a more basic

version at home”. Here, the author tells us that he or she wants to give us some ways to

make a more basic pizza at home.

The author spends the rest of the passage outlining the steps we need to take to make the

pizza. This means option (c) is correct. The passage does not provide information to support

choices (a), (b), and (d). Therefore they are incorrect.