
Daily subject-wise quiz : Science and Technology MCQs on Zero Shadow Day, tumour marker test and more (Week 110)
🚨 Click Here to read the UPSC Essentials magazine for April 2025. Share your views and suggestions in the comment box or at manas.srivastava@indianexpress.com🚨
Consider the following statements about Zero Shadow Day:
1. It occurs when the Sun's declination—its angular distance north or south of the celestial equator—matches the latitude of a particular location.
2. It occurs thrice a year in regions situated between the Tropic of Cancer and the Equator
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
— Several regions in West Bengal will witness the rare and scientifically significant phenomena known as Zero Shadow Day (ZSD) this year in June and July.
— This astronomical occurrence occurs twice a year in places between the Tropic of Cancer and the Equator, when the Sun is directly overhead at local noon, allowing objects to cast no shadows for a brief duration. Hence, statement 2 is not correct.
— Zero Shadow Day happens when the Sun's declination (angular distance north or south of the celestial equator) corresponds to the latitude of a certain location. Hence, statement 1 is correct.
— At that same instant, the Sun reaches its greatest position in the sky, straight overhead, casting no visible shadow on upright objects. The effect is most visible for a few minutes at solar noon, when the Sun crosses the local meridian.
Therefore, option (a) is the correct answer.
The monographs (related to upper atmosphere) are the instruments which measure:
1. Pressure
2. Temperature
3. Relative humidity
Select the correct answer using the codes given below:
(a) 1 and 2 only
(b) 2 only
(c) 3 only
(d) 1, 2 and 3
Explanation
— In the wake of budget cuts by the Trump administration, a Silicon Valley startup will soon start to replace the National Oceanic and Atmospheric Administration's (NOAA's) weather balloons with AI-powered alternatives, which are supposed to be much cheaper.
— Weather balloons are used by weather agencies all around the world to collect upper air measurements, which are critical for forecasting. Upper air refers to the Earth's atmosphere above 5,000 feet, from which the globe receives rain and drought, wind and stillness, heat and cold at its surface.
— The practice of making upper-air observations dates back to the 18th century. It all started in 1749, when two students from Glasgow, Scotland, used kites to record temperature at great altitudes. Meteorologists began to deploy kites into the high atmosphere carrying aloft sensors known as monographs, which measured pressure, temperature, and relative humidity.
Therefore, option (d) is the correct answer.
With reference to the microalgae, consider the following statements:
1. They are microscopic algae with high chlorophyll content that lack lignin and cellulose but contain proteins.
2. They are primarily found in freshwater.
3. It can be used to treat industrial wastewater.
4. It can recycle CO2 to O2 while providing nourishment.
How many of the statements given above are correct?
(a) Only one
(b) Only two
(c) Only three
(d) All four
Explanation
— Microalgae are known to grow quicker in microgravity environments and can recycle CO2 to O2 while producing nourishment. Hence, statement 4 is correct.
— Microalgae are microscopic algae with high chlorophyll content that lack lignin and cellulose but contain proteins. Hence, statement 1 is correct.
— Microalgae are primarily found in freshwater and marine ecosystems. Hence, statement 2 is correct.
— Microalgae can be successfully used to treat industrial wastewater. According to the researchers, as the microorganisms feed, they expand and reproduce, offering a wealth of algae-based biomass for the production of bioenergy, high-value bio-based chemicals, and speciality items. Hence, statement 3 is correct.
Therefore, option (d) is the correct answer.
The Indian Space Research Organisation (ISRO) inked a Joint Statement of Intent on Human Space Exploration on the sidelines of the Global Space Exploration Conference (GLEX) – 2025 with:
(a) European Space Agency (ESA)
(b) National Aeronautics and Space Administration (NASA)
(c) Japan Aerospace Exploration Agency (JAXA)
(d) Roscosmos
Explanation
— The European Space Agency (ESA) now has direct and clearer objectives for working with India, and it is willing to collaborate on larger and undiscovered areas of space, according to Dr Josef Aschbacher, the ESA director general.
— The Indian Space Research Organisation (ISRO) and the European Space Agency (ESA) signed a Joint Statement of Intent on Human Space Exploration on the margins of the Global Space Exploration Conference (GLEX) 2025.
— ESA is pleased to collaborate with ISRO and looks forward to investigating large-scale space activities. It is a significant honour for ESA and ISRO to collaborate in the field of space exploration.
— Collaborations are being considered for India's projected Bharatiya Antariksha Station (BAS). India intends to build the space station by 2035. The BAS-1, which has five modules, is expected to launch in 2028.
Therefore, option (a) is the correct answer.
With reference to the tumour marker test, consider the following statements:
1. A tumour marker test measures the number of substances called tumour markers in tissue, blood, urine, or other body fluids.
2. Most tumour markers are proteins made by both normal cells and cancer cells, but they are made in higher amounts by normal cells.
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
— A tumour marker test, according to the National Cancer Institute, counts the number of chemicals known as tumour markers in tissue, blood, urine, or other body fluid. Hence, statement 1 is correct.
— 'The majority of tumour markers are proteins produced by both normal and cancer cells, but cancer cells produce more of them. Genetic changes in cancer tissue, including as gene mutations, gene expression patterns, and other DNA modifications, are also utilised as tumour indicators. Hence, statement 2 is not correct.
— Tumour marker tests include Prostate-specific antigen (PSA), Prostatic acid phosphatase (PAP), CA 125, Carcinoembryonic antigen (CEA), Alpha-fetoprotein (AFP), CA 19-9, CA 15-3, CA 27-29, Lactate dehydrogenase (LDH), and bladder tumour marker investigations.
Therefore, option (a) is the correct answer.
Daily Subject-wise quiz — History, Culture, and Social Issues (Week 109 and 110)
Daily subject-wise quiz — Polity and Governance (Week 110)
Daily subject-wise quiz — Science and Technology (Week 109)
Daily subject-wise quiz — Economy (Week 109)
Daily subject-wise quiz — Environment and Geography (Week 109)
Daily subject-wise quiz – International Relations (Week 109)
Subscribe to our UPSC newsletter and stay updated with the news cues from the past week.
Stay updated with the latest UPSC articles by joining our Telegram channel – IndianExpress UPSC Hub, and follow us on Instagram and X.
Hashtags

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles


India Today
8 hours ago
- India Today
Is it spying on us? Nasa could turn Juno towards interstellar object near Jupiter
Months after ground telescopes on Earth discovered the third interstellar object infiltrating our Solar System, scientists are raising concerns that it may be more than object named 3I/ATLAS is set to make a close pass near Jupiter on March 16, 2026, at approximately 53.5 million kilometers. The arrival of this rare visitor from beyond our solar system has spurred scientists to consider an unprecedented move: rerouting Nasa's Juno spacecraft, currently orbiting Jupiter, to intercept and study the object up in July 2025, 3I/ATLAS is the third confirmed interstellar visitor traversing our solar system, following 'Oumuamua and Comet Borisov. It is notable for its large nucleus, estimated at around 5.6 kilometers in diameter, and its high speed of 58 km/s relative to the Sun. Unlike prior interstellar visitors, 3I/ATLAS's trajectory will bring it relatively close to Jupiter, offering a unique opportunity for direct scientific plan, proposed in a draft paper, involves a precise engine burn by Juno on September 9, 2025, to adjust its orbit around Jupiter. Utilising a gravity-assisted 'Jupiter Oberth Manoeuvre,' Juno would gain the velocity and directional change needed to intercept 3I/ATLAS about two days before the comet's closest approach to Jupiter, potentially as near as 27 million manoeuvre is fuel-efficient, requiring only about 110 kg of Juno's remaining propellant, just 5.4% of its original fuel Juno is equipped with advanced instruments capable of probing 3I/ATLAS's composition and behaviour. These include a near-infrared spectrometer, magnetometer, microwave radiometer, and cameras that together could reveal the object's makeup and the nature of its coma and dust tail—details unattainable from Earth-based telescopes. There is also speculative intrigue around the nature of 3I/ATLAS. (Photo: Nasa) Insights gained could dramatically deepen understanding of interstellar visitors and their origins, shedding light on the properties of materials from other star is also speculative intrigue around the nature of 3I/ATLAS, with some discussions about whether such interstellar travellers could be natural objects or potentially artificial this remains unconfirmed, the ability for Juno to closely observe 3I/ATLAS could provide critical data to clarify its mission extension could both rejuvenate Juno's scientific lifespan and represent a new frontier in interstellar object exploration, capitalising on a rare celestial visitor as it journeys through our cosmic neighbourhood.- Ends


Time of India
16 hours ago
- Time of India
‘They want a win in November': Trump administration schedules first ‘Golden Dome' test ahead of 2028 election -Here's what report said
The Pentagon has scheduled its first major test of President Donald Trump's space-based Golden Dome missile defence system just before the 2028 elections, CNN reported, citing sources. This ambitious schedule aims to demonstrate the feasibility of transforming President Trump's concept of a space-based protective shield for the entire United States. This scheduling aligns with Trump's May announcement to 'have it done in three years.' "Once fully constructed, the Golden Dome will be capable of intercepting missiles even if they are launched from other sides of the world," he said. A defence official informed CNN that while missile tests typically require extensive advance planning, the timing of this test in the fourth quarter of 2028 appears strategically placed. "They want a win to point to in November [2028],' the official told CNN and added, 'and DoD wants to avoid anything they perceive will slow them down.' The defence official revealed that the MDA plans to designate the test as FTI-X, where 'FTI' indicates Flight Test Integrated, encompassing the coordination of Golden Dome's various sensors and weapons systems against multiple targets. The three-year implementation presents significant challenges, considering the US has researched space-based missile interception for decades. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like Average Cost To Rent A Private Jet May Surprise You (View Prices) Private Jet I Search Ads Learn More Undo The defence official highlighted technical complexities, particularly regarding the substantial number of satellites required for effective coverage of the continental United States. Space Force Gen. Michael Guetlein, appointed by Trump in May to oversee Golden Dome's development, addressed these challenges at a recent industry summit, focusing on the technical and economic feasibility of space-based interceptors at scale. Initial tests in 2028 may represent only the first phase, according to another source, emphasising the current focus on swift progress using existing systems to demonstrate the concept's viability for additional funding. The project's allocated budget of $25 billion, announced by Trump in May, is expected to expand significantly into hundreds of billions. Various companies are already testing relevant technologies, including Northrop Grumman's work on space-based interceptors. The Pentagon recently announced successful testing of a Lockheed Martin long-range radar system in Alaska, capable of tracking ballistic missiles from Russia and China, likely to be incorporated into Golden Dome. The industry awaits Guetlein's comprehensive system design plan. A memo signed by defence secretary Pete Hegseth outlined a 60-day deadline for initial architecture and 120 days for implementation planning. Concerns exist regarding the accelerated development approach and reduced oversight. The Office of the Director of Operational Test and Evaluation's role was diminished after announcing its involvement in Golden Dome testing oversight. Guetlein has been granted significant autonomy in contract allocation and technology procurement, reporting directly to Deputy Secretary Stephen Feinberg. The programme operates outside standard Pentagon oversight procedures for major weapons systems. Multiple companies, notably SpaceX, Anduril, and Palantir, are competing for involvement, having presented directly to Hegseth, who has expressed interest in their proposals.


Economic Times
a day ago
- Economic Times
Moon tonight shines at 69 percent brightness as Waxing Gibbous phase illuminates the sky
TIL Creatives The Moon is in its Waxing Gibbous phase tonight, with 69 percent of its surface illuminated, offering stunning views of craters and lunar seas as it moves closer to next week's full moon Skywatchers across the United States can expect a dazzling display in tonight's sky as the Moon enters a Waxing Gibbous phase, lighting up 69 percent of its surface, according to NASA's Daily Moon Observation. The glowing lunar disk is steadily building toward the next full moon, expected on August 9. Moon tonight(August 3) marks day 10 of the lunar cycle, part of the Moon's ongoing 29.5-day journey around Earth. These cycles, new moon to full moon and back again, are created by the Sun's light reflecting off different portions of the Moon's surface as it orbits Earth. It's a rhythm that has guided humanity for millennia. The Waxing Gibbous moon is more than halfway lit but not yet full. As it rises in the eastern sky just before sunset and sets shortly after midnight, it creates an excellent opportunity for both casual stargazers and astronomy enthusiasts. Even without any equipment, you can spot major features like the Copernicus Crater, Mare Fecunditatis, and Mare Crisium. Binoculars will reveal the Alphonsus Crater, Posidonius Crater, and Mare Frigoris. Those with telescopes can explore the Rima Ariadaeus, the Descartes Highlands, and the Fra Mauro Highlands, where Apollo 14 once landed. According to NASA, there are eight primary phases of the Moon: New Moon, Waxing Crescent, First Quarter, Waxing Gibbous (tonight's phase), Full Moon, Waning Gibbous, Last Quarter, and Waning always see the same side of the Moon, but the amount illuminated changes as it orbits Earth. That shifting glow creates the lunar phases we observe each night.