Context: The Indian Air Force (IAF), which is short of Airborne Early Warning and Control (AEW&C) aircraft, a critical force multiplier, is looking for the procurement of 12 new aircrafts.
Major Highlights:
The IAF is planning to acquire 12 new Airborne Early Warning and Control (AEW&C) aircrafts under two different programmes.
One of them is a follow-on order of six AEW&C systems mounted on Embraer aircraft.
IAF already operates three Netra AEW&C systems mounted on Embraer aircrafts.
These aircrafts will be purchased from Embraer, while DRDO Centre for Air Borne Systems (CABS) will be doing the necessary modifications to their equipment.
Another order pertains to six AEW&C systems under development by the Defence Research and Development Organisation (DRDO) that would be mounted on Airbus A-321 aircraft.
The AEW&C mounted on the Airbus aircraft would provide 300-degree coverage.
Airborne Early Warning and Control (AEW&C) System:
Airborne Early Warning & Control System (AEW&C) is a force multiplier system that uses advanced radars fordetection & tracking enemy/hostile aircrafts/ UAVs etc. from a considerable distance (primarily long-distance).
The systems use advanced communication equipment to share real-time data with operators onboard and on ground to identify, assess the threat and take actions to guide specific interceptors (fighter jets or surface-to-air missiles) towards the airborne threats to neutralise them.
Significance: In Indian context, AEW&C systems can play a vital role to maintain national airspace security, especially along the China and Pakistan border.
Presently, India operates two types of AEW&C systems:
Netra AEW&C:
Indigenous system developed by DRDO in collaboration with IAF.
Mounted on Embraer ERJ-145 jets.
Netra provides 240-degree coverage of airspace.
Range over 200 kms.
Phalcon AWACS:
India presently operates three Phalcon Airborne Warning and Control Systems (AWACS).
The Israeli-made system ismounted on top of an IL-76 transport aircraft.
Provides 360-degree radar coverage.
Detects aircraft at ranges exceeding 400 kilometres.
Context: The Government of India, while presenting the Union Budget for FY 2024-25, inter alia, made announcements on the expansion of India’s nuclear energy sector, proposing partnerships with the private sector for research and developing Bharat Small Reactors (BSR), Bharat Small Modular Reactors (BSMR) as well as newer nuclear energy technologies.
India’s three Stage nuclear programme
1st Stage: Pressurised Heavy Water Reactor
The first stage includes the setting up of Pressurised Heavy Water Reactors (PHWRs) and associated fuel cycle.
PHWRs use natural uranium (U-238) as fuel and heavy water (deuterium oxide) as coolant and moderator.
The Nuclear Power Corporation of India Limited (NPCIL) presently operates 22 commercial nuclear power reactors with an installed capacity of 6,780 MWe.
2nd Stage: Fast Breeder Reactors:
The Fast Breeder Reactor (FBR) will initially use the Uranium-Plutonium Mixed Oxide (MOX) fuel.
The Uranium-238 surrounding the fuel core will undergo nuclear transmutation to produce fuel (Plutonium, Pu-239), thus earning the name ‘Breeder’.
Also, by transmutation, Thorium-232 will create fissile Uranium-233 which will be used as fuel in the third stage.
In 2003, the Government had approved the creation of Bharatiya Nabhikiya Vidyut Nigam Ltd (BHAVINI) to construct and operate India’s most advanced nuclear reactor-Prototype Fast Breeder Reactor (PFBR). Once the FBR attains criticality, India will only be the second country after Russia to have a commercial operating Fast Breeder Reactor.
Benefits of FBR
FBR is thus a stepping stone for the third stage of the program paving the way for the eventual full utilisation of India’s abundant thorium reserves.
Electricity generated by FBR would be a source of green energy as the waste (Plutonium) from the first stage nuclear programme is reprocessed and used as fuel in FBR. Hence, it offers significant reduction in nuclear waste generated, thereby avoiding the need for large geological disposal facilities.
In terms of safety, the PFBR is an advanced reactor with inherent passive safety features ensuring a prompt and safe shut down of the plant in the event of an emergency.
Despite the advanced technology involved, both the capital cost and the per unit electricity cost is comparable to other nuclear and conventional power plants.
Hence, the second stage of the Indian nuclear power program is imperative to meet the twin goals of energy security and sustainable development.
3rd Stage: Thorium-based Reactors
The third stage will utilise India’s vast Thorium reserves. For it an Advanced Heavy Water Reactor (AHWR) is proposed that will use Uranium-233.
By transmutation, Thorium will create fissile Uranium-233 which will be used as fuel in the third stage.
Key Points
Aims to achieve 500 Gigawatts of non-fossil fuel energy by 2030, as pledged at COP26, Glasgow 2021.
Investment and Capacity Goals:
India’s country profile, as published by the World Nuclear Association in September 2024 recognises an in-principle proposed gross increment of 32 GWe in the Indian nuclear energy production capacity.
The ambitious expansion requires significant capital investment and skilled resources.
Legislative hurdles for private participation
The Atomic energy act 1962, the primary governing statute at the helm of the development and the operation of the nuclear energy sector.
Pertinently, Section 3(a) of the AEA, 1962 empowers only the central government “to produce, develop, use and dispose of atomic energy”.
The AEA gives the government sole control and responsibility over all activities in respect of nuclear energy either through an authority or company established by it.
In essence, the Department of Atomic Energy (DAE) and the Nuclear Power Corporation of India Limited (NPCIL) currently have overarching control over the nuclear energy infrastructure.
Supreme Court Ruling (September 2024): Sandeep T.S. vs Union of India & others.
Dismissed a petition challenging AEA’s restrictions on private participation, emphasizing strict regulatory safeguards due to potential misuse and accidents.
Regulatory Uncertainty:
Ongoing legal challenges to the Civil Liability for Nuclear Damage Act, 2010 (CLNDA), create uncertainty for private investments.
CLNDA aims to ensure no-fault liability of operators for nuclear accidents, but its constitutionality is under scrutiny.
The Civil Liability for Nuclear Damage Act, 2010 (CLNDA) is a significant piece of legislation in India that addresses liability and compensation for nuclear damage.
Objective: The Act aims to provide a framework for compensating victims of nuclear damage arising from a nuclear incident. It establishes a no-fault liability regime, meaning the operator of a nuclear facility is liable for damages regardless of fault.
Liability: The operator of the nuclear installation is primarily liable for nuclear damage. The Act caps the maximum liability of the operator at ₹1,500 crore (approximately $180 million). If the damage exceeds this amount, the Central Government will cover additional costs up to 300 million Special Drawing Rights (SDRs).
Claims Commissioner: The Act provides for the appointment of a Claims Commissioner to adjudicate claims for compensation. It also establishes a Nuclear Damage Claims Commission to handle larger claims and ensure prompt compensation.
Right of Recourse: The operator has the right to recourse under certain conditions, such as if the nuclear incident results from an act of terrorism or if the damage is caused by a supplier’s defective equipment.
Insurance: Operators are required to maintain insurance or other financial security to cover their liability for nuclear damage.
Exclusion of Jurisdiction: Civil courts are excluded from entertaining any suit or proceeding related to claims for nuclear damage, ensuring that all claims are handled by the designated authorities.
This Act was crucial for operationalizing the 2008 Indo-U.S. civilian nuclear agreement, as it provided the necessary legal framework for foreign companies to participate in India’s nuclear energy
Financial Risks: Nuclear projects require substantial upfront investment and have long gestation periods. The high costs and financial risks deter private investors, especially given the uncertainties around project completion and return on investment.
Public Perception and Acceptance: Public opposition to nuclear power due to safety concerns and environmental impact can affect the willingness of private companies to invest. Building public trust is crucial but challenging.
Technological Challenges: Developing and maintaining nuclear technology requires specialized knowledge and infrastructure. The private sector may lack the necessary expertise and resources to manage these complex technologies.
Waste Management: Handling and disposing of nuclear waste is a critical issue. The long-term storage and management of radioactive waste pose significant challenges and require stringent regulatory compliance.
Market Competition: Nuclear power competes with other forms of energy, such as renewables, which are often cheaper and face fewer regulatory hurdles. This makes it harder for nuclear power to attract private investment
Current status of Private Sector Involvement:
Historically limited to engineering, procurement, and construction (EPC) roles, with companies like Megha Engineering & Infrastructures participating.
Measures to increase private investment
NITI Aayog Report:
Discusses promoting private sector involvement in Small Modular Reactors (SMRs) and emphasizes the need for:
A supportive regulatory framework.
A clear civil nuclear liability framework.
Public-Private Partnerships (PPP):
Proposed structure where government retains 51% ownership of nuclear plants, allowing private investment while ensuring government accountability.
Entities with majority government ownership would be subject to transparency requirements under the Right to Information Act.
Liability Concerns:
High liability standards are necessary due to the risks associated with nuclear technology, as evidenced by past disasters like Chernobyl and Fukushima.
Compensation for nuclear incidents is governed by the CLNDA, but its constitutionality is being challenged, raising concerns over the adequacy of liability protections.
Legislative Needs:
Comprehensive legislation is essential to address the sensitive nature of nuclear technology and foster a conducive business environment.
Legislative and policy adjustments will be crucial for achieving India's energy generation goals through renewable sources.
The path for private participation in India’s nuclear energy sector requires careful navigation of existing laws and challenges, with significant implications for investment and regulatory frameworks.
Context: Scientists working on the LUX-ZEPLIN (LZ) experiment have placed the tightest restrictions on the particles that make up dark matter (i.e., they have significantly narrowed down possibilities for what dark matter could be), still, the result remains inconclusive. Despite similar global experiments, such as XENON-nT in Italy and PandaX-4T in China, there is no definitive direct evidence of dark matter.
Major Highlights
Dark matter constitutes most of the universe's mass but interacts weakly with ordinary matter. Theories suggest it may occasionally "touch" atomic nuclei, but detecting this interaction is challenging.
In 1985, physicists Goodman and Witten proposed using large underground detectors to catch dark matter particles as they pass through. These experiments measure the cross-section, or likelihood of interaction, between dark matter and nuclei.
The LZ experiment pushed detection limits even further, reducing the cross-section of possible dark matter interactions by a factor of a million. However, the future progress may be hindered by interference from neutrinos, another elusive particle.
The "neutrino fog" adds noise to detectors, complicating the identification of dark matter.
Despite these challenges, researchers continue to explore alternative detection methods, driven by the determination to uncover dark matter's true nature.
LUX-ZEPLIN (LZ) experiment
The LUX-ZEPLIN (LZ) experiment is a leading dark matter direct detection experiment designed to search for weakly interacting massive particles (WIMPs), a potential candidate for dark matter.
Objective: To measure the interaction of dark matter particles with atomic nuclei of ordinary matter (known matter). This interaction, if detected, would provide critical insights into the nature of dark matter, its mass, and its interaction cross-section with ordinary matter.
Detector: LZ employs a massive 7-tonne liquid xenon detector. The liquid xenon acts as a target for dark matter particles. If a dark matter particle collides with a xenon nucleus, it would cause a small burst of light (scintillation) and ionisation, which the detector would capture and measure.
To minimise interference from cosmic rays and other background sources, LZ is located 1.5 kilometres below the Earth's surface at the Sanford Underground Research Facility (SURF) in South Dakota, The US.
Dark Matter and Dark Energy
Dark matter and dark energy together make up 95% of the universe. Around 68% of the Universe is made of dark energy while dark matter makes up 27%.
Only the remainder (5%) is composed of fermionic matter, i.e., things on the Earth, planets, stars, etc.
Dark Matter
Dark matter is completely invisible and has not yet been observed directly. It does not interact with matter in the same way that normal matter does, meaning it does not absorb, reflect, or emit light. This makes it extremely difficult to detect using conventional telescopes or other detectors.
In fact, researchers have been able to infer the existence of dark matter only from the gravitational effect it seems to have on visible matter (galaxies and galaxy clusters).
E.g., Galaxy Rotation Curves
Expected Behaviour: In galaxies, stars or planets should orbit faster closer to the centre of the galaxy, due to the gravitational pull of the visible matter concentrated there.
Observed Anomalies: However, observations show that stars and gas in galaxies continue to orbit at a relatively constant speed even at large distances from the centre. This suggests the presence of additional invisible matter exerting gravitational force.
Dark Energy
The existence of dark energy was theorised 25 years ago, when a team of researchers found that the expansion of the Universe was speeding up or accelerating, instead of slowing down due to gravity (inwards pulling force). Scientists have hypothesised that this is happening due to a mysterious form of energy called dark energy.
Characteristics of dark energy:
Dark energy has been hypothesised as a repulsive force or anti-gravity, i.e. while gravity tends to make objects attract, dark energy would pull them apart by increasing the space between them. Thus, dark energy has an expansionary effect. As our universe is expanding, it indicates that dark energy has a greater abundance than dark matter.
Dark energy is a property of space, so it does not get diluted as space expands.
Normally, as the universe expands the density of mass and radiation in it decreases.
However, the density of dark energy remains constant throughout. This means the dark energy in the universe is ever increasing, in order to keep the energy-density constant. Thus, dark energy should be energy inherent in the fabric of space itself.
Context: After the success of the Mars Orbiter Mission (Mangalyaan) and Chandrayaan lunar missions, India now aims to explore Venus with its proposed Venus Orbiter Mission (Shukrayaan).
Venus Orbiter Mission:
The Union Cabinet has approved India’s first mission to Venus which ISRO aims to launch in March 2028. This is the country’s second interplanetary mission after the Mars Orbiter Mission launched in 2013.
The mission is being developed by the Indian Space Research Organisation (ISRO).
Objective: To study the planet’s atmosphere, surface, and geological features using sophisticated scientific instruments.
Study the structure, composition, and dynamics of Venus's atmosphere.
Investigate surface processes and subsurface stratigraphy.
Explore solar wind interactions with the Venusian ionosphere.
The mission will place a spacecraft in orbit around Venus. Once the satellite exits the Earth orbit, it will take around 140 days to reach Venus.
The mission will carry scientific payloads weighing around 100 kg. The orbiter is expected to carry instruments like synthetic aperture radar, infrared and ultraviolet cameras, and sensors that will study Venus’s ionosphere.
The mission will also see India perform aero-braking for the first time.
Aero-braking is a technique used to reduce a satellite's orbit by using atmospheric drag instead of relying solely on fuel-powered engines.
It is particularly useful for missions to planets with significant atmospheres, like Venus, where it helps conserve fuel while gradually lowering the satellite's altitude.
Significance of the mission:
Clues about Earth's Evolution: Venus is often termed "Earth's twin" due to its similar size, mass, and density. By studying Venus, scientists can gather valuable information about how planetary bodies evolve over time. Understanding why Venus evolved into a hot, dry planet while Earth remains habitable may offer critical insights into planetary development, particularly for Earth-like planets.
Insights into Venus's Atmosphere: The mission will provide key insights into the thick clouds that shroud Venus, composed primarily of carbon dioxide and sulfuric acid, and explore whether there are any signs of active volcanoes.
Clues about Climate Change and Atmospheric Dynamics: Scientists believe that more than four billion years ago, Venus had enough water to cover its surface with an ocean 3 km deep. But now the planet has become dry and dusty. By comparing Venus’s climate with Earth’s, scientists hope to better understand how climate change affects planetary atmospheres.
Facts about Venus:
Venus has a solid surface by virtue of being one of the 3 inner planets besides Mercury and Earth. It is nearly the same size as the Earth.
96.5% of the atmosphere of Venus is made up of carbon dioxide and there are sulphuric acid clouds on the planet. Thus, the palnet has a high greenhouse effect.
It has an extremely high surface temperature of around 462 degree Celsius, even hotter than Mercury (the planet that is closest to the Sun).
This may be possible due to a runaway greenhouse effect. The water present on the Venusian surface has evaporated because of the proximity of the planet to the Sun.
As water vapour is a greenhouse gas, it led to the planet trapping more heat and further evaporating water from its surface.
The atmospheric pressure on Venus is much higher than on Earth. It is almost similar to the pressure felt underneath the oceans on Earth.
Surface pressure on Venus is about 90 times that on Earth while surface pressure on Mars is 1/100th of that on Earth.
Venus rotates very slowly on its axis as compared to Earth. One rotation of Venus lasts around 243 Earth days.
Its rotation period is longer than its orbital period. (Rotation on its own axis – 243 days, Orbital period around the sun - 224.7 days).
The planet has retrograde rotation, meaning it spins in the direction opposite to the direction in which it orbits the Sun.
Due to the slow rotation of Venus it has no global magnetic field. (Earth’s magnetic field is due to rotation of iron core).
NASA’s image data from the Magellan spacecraft's visit to Venus has revealed evidence of volcanic activity on it. About 80% of the surface of Venus is composed of flat plains of volcanic origin.
Upcoming Venus missions:
The US has planned at least two more missions to Venus in the future — DaVinci in 2029 and Veritas in 2031.
NASA's DAVINCI (Deep Atmosphere Venus Investigations of Noble gases, Chemistry, and Imaging) mission will study Venus from above its clouds down to its surface, investigating how the planet and its dense atmosphere formed and evolved over the past 4.5 billion years. Tentatively scheduled to be launched in June 2029 and would enter the Venusian atmosphere in June 2031.
VERITAS: NASA's VERITAS (Venus Emissivity, Radio Science, InSAR, and Spectroscopy) mission is expected to be launched in 2031. VERITAS will use a suite of seven instruments to study the surface and atmosphere of Venus.
The European Space Agency (ESA) has planned the EnVision mission for 2030. EnVision will study the atmosphere, surface, and interior of Venus.
Context: A recent study published in “Earth and Planetary Science Letters” suggests that Earth may have once had rings similar to those of Saturn.
Major highlights of the study:
Scientists from Monash University, Australia analysed 21 crater sites on Earth from the Ordovician period (488-443 million years ago) and found that all impacts occurred near the equator, which is unusual since asteroid impacts usually occur at random latitudes. This suggests the presence of a ring over Earth's equator during that period.
This ring would have formed around 466 million years ago when an asteroid passing too close to Earth broke apart due to its gravity, and created a debris-laden ring around the equator. Over time, the debris from the ring fell to Earth, with larger pieces forming craters near the equator.
The ring over Earth’s equator would have had a profound impact on the Earth’s climate. The axial tilt of Earth relative to the Sun would mean that the rings would have shaded the winter hemispheres and increased solar flux to the summer hemispheres, potentially contributing to global cooling. Notably, Earth experienced significant cooling around 460-445 million years ago, coinciding with the peak of the Hirnantian Ice Age. However, further research and modelling are needed to confirm the connection.
Roche limit:
The Roche limit is the closest distance at which a satellite can approach its primary body (e.g., a planet) without being torn apart by the tidal forces exerted by the larger body.
In a two-body system, such as a planet and its satellite, two key forces act on the smaller body:
Internal Gravity of the Satellite: This is the cohesive force that holds the satellite together, resisting external forces.
Tidal Force from the Larger Body: This is the gravitational pull of the larger body (planet), which stretches the satellite and tries to pull it apart, especially along the line of gravitational force between the two.
When a satellite orbits beyond the Roche limit, its internal gravity is strong enough to resist the tidal forces, allowing it to maintain its structural integrity and orbit stably around the planet. E.g., Our Moon
In the case of Earth, our moon is safely located far beyond the Roche limit, which is why it remains intact and orbits without disintegrating.
However, if the satellite crosses within the Roche limit, the tidal forces of the planet become stronger than the satellite's own gravity, causing it to disintegrate. The resulting debris from this disintegration forms a ring around the planet, much like the rings we see around Saturn and other gas giants.
Context: A recent study published in ‘Astronomy & Astrophysics’ reveals that Elon Musk's Starlink satellites are disrupting the work of astronomers. Experts argue that this growing issue underscores the urgent need for regulations governing satellite operators, similar to those in place for controlling radio pollution from ground-based sources like cell-phone towers.
The impact of Starlink Satellites on Radio astronomy:
Starlink, a satellite internet constellation operated by SpaceX, currently has over 6,300 active satellites orbiting Earth at an altitude of approximately 550 km.
While these satellites are instrumental in delivering high-speed internet to remote areas, they are also a source of unintended electromagnetic radiation (UEMR), commonly referred to as ‘radio noise.’
This interference poses significant challenges to radio astronomers, as it disrupts their ability to observe celestial objects from Earth.
Understanding Radio astronomy and Radio noise:
Radio astronomy is a specialized branch of astronomy that focuses on studying celestial bodies by detecting radio frequencies, which are much higher in wavelength and lower in frequency than the visible light detected by optical telescopes.
Unlike optical telescopes, which rely on visible light, radio telescopes are designed to capture radio waves emitted by objects in space.
However, much like how bright visible light can overwhelm a viewer’s vision-akin to the glare of oncoming car headlights-radio frequencies can similarly ‘blind’ radio astronomers.
Cees Bassa, a researcher at the Netherlands Institute for Radio Astronomy (ASTRON), explained that the radio noise from satellites is making it increasingly difficult to study the faint signals from distant objects in the universe.
‘Blinding’ scientists means that the eyes are collecting too much light to see anything clearly.
The growing challenge of UEMR:
The study found that Starlink’s second-generation satellites-though currently accounting for less than a third of the overall network-emit UEMR at levels that are 32 times brighter than their first-generation counterparts.
This is a worrying trend, especially since the first-generation satellites had already raised concerns regarding radio leakage.
The situation could worsen further as the satellite industry continues to expand. With advancements in technology making satellite launches cheaper, estimates suggest that up to 100,000 satellites could be orbiting Earth by 2030.
As of June 2023, the United Nations Office for Outer Space Affairs (UNOOSA) reported the presence of around 11,330 satellites in orbit.
The growing number of satellites will only increase the risk of UEMR and radio interference for astronomers.
Need for regulatory oversight:
These developments underscore the urgent need for regulations governing satellite operators, much like the existing regulations that control radio pollution from ground-based electronic sources such as cell-phone towers.
Currently, astronomers rely largely on good faith agreements with companies like Starlink to minimize interference.
However, this informal approach may not be enough as the number of satellites and the intensity of UEMR increase.
In the absence of stringent regulations, the increasing UEMR from satellite constellations could pose an existential threat to radio astronomy, blinding telescopes to the faint signals that scientists rely on to explore the universe.
About Starlink Project:
It is the world's first and largest satellite constellation using a Low Earth orbit to deliver broadband internet capable of supporting streaming, online gaming, video calls, and more.
It delivers high-speed, low-latency internet to users all over the world. This system is ideally suited for rural and geographically isolated areas where internet connectivity is unreliable or non-existent.
The satellites are equipped with Hall thrusters, which are used to manoeuvre in orbit, maintain altitude, and guide the spacecraft back into the atmosphere after their missions. Hall thrusters generate an impulse using electricity and krypton gas.
It operates on a satellite internet service technology that has existed for decades. Instead of using cable technology to transmit internet data, a satellite system uses radio signals through the vacuum of space.
It offers unlimited high-speed data through an array of small satellites that deliver up to 150 Megabits per second (Mbps) of internet speed.
It uses Low Earth Orbit (LEO) satellites and a phased array antenna to help keep its performance intact during extreme weather conditions.
In 2019, SpaceX initiated the launch of these satellites into space.
Unlike conventional internet providers, it operates without the need for ground infrastructure. Users only require a small satellite dish or a receiver device, similar to satellite TV, to access high-speed internet.
It can withstand extreme cold, heat, hail, sleet, heavy rain, gale-force winds, and even rocket engines.
A telescope is an optical instrument that allows us to observe distant objects by collecting and focusing light.
Contrary to the common belief that telescopes are primarily designed to make objects appear larger, their main function is to increase the brightness of celestial objects. This is achieved through their light-gathering power, which determines how much light they can collect from faint or distant sources.
The key factor that influences a telescope’s light-gathering ability is its aperture (the size of the opening through which light enters). The larger the aperture, the more light the telescope can capture, resulting in brighter and clearer images of celestial bodies.
Aperture refers to the diameter of the telescope's opening (objective lens) that controls how much light is allowed to pass through. A larger aperture allows more light to be gathered, making faint objects, such as distant stars and galaxies, visible.
For instance, when the human eye’s pupil is fully dilated, its aperture area is about 153.9 square millimetres. In contrast, a small 0.07-meter reflecting telescope (commonly available as a toy) has an aperture area of 18,241.4 square millimetres. This means the telescope has 118.5 times more light-collecting area than the human eye, allowing it to capture much more light and make dim objects easier to see.
Two types of telescopes:
Celestial objects emit light in all directions. But only light rays travelling in the direction of the earth will reach us. And when these rays reach us after a lengthy journey, they are virtually parallel.
There are two ways to concentrate these rays and create an image.
Reflecting Telescopes:
In a reflecting telescope, rays reflected by the primary mirror (concave mirror) are diverted to a secondary mirror, which reflects them into an eyepiece with a small lens (convex lens) to enhance the image.
The image produced by this reflecting telescope is real, inverted, and smaller. Most contemporary telescopes are such reflecting telescopes. E.g., Hubble Space Telescope, James Webb Space Telescope, Very Large Telescope (Chile) etc.
Primarily used for Deep-Sky observation: Reflecting telescopes have larger mirrors (and thus larger apertures). Larger apertures allow reflectors to gather more light, which is crucial for viewing faint objects like distant galaxies, nebulae, and star clusters.
Advantages:
More cost-effective to produce larger mirrors (for reflecting telescopes) than larger lenses (used in refracting telescopes).
No chromatic aberration since mirrors reflect all wavelengths equally.
A refracting telescope is an optical instrument that uses lenses to gather and focus light in order to magnify distant objects. It typically consists of two main lenses:
Objective Lens: The primary lens that collects light and brings it to a focus, forming an image.
Eyepiece Lens: The secondary lens that magnifies the image formed by the objective lens for viewing.
Primarily used forhigh-magnification observations: Refractors excel at viewing bright objects (e.g., planets, Moon, stars) because their lenses can focus light sharply without the interference of additional mirrors. They are better suited for high-magnification observations where sharp, clear images are priority. E.g., Yerkes Observatory Refracting Telescope, the US.
Advantages:
Produces sharp, high-contrast images, especially for planetary observations.
Generally easier to maintain than reflecting telescopes.
Disadvantages:
Can become expensive as lens size increases. (Can be more expensive than reflecting telescopes of the same aperture)
Limit on lens size: To observe fainter cosmic objects, much bigger lenses are required, which will slump under their own weight and distort the image. The maximum practicable lens size in a refracting telescope is around 1 m. The world’s largest refracting telescope is at Yerkes Observatory in the U.S., with a 1.02-m lens.
Chromatic aberration (colour fringing) can occur, especially in larger refractors.
Chromatic aberration:
Chromatic aberration is a type of optical distortion that occurs when a lens fails to focus all colours of light at the same point. This results in a blurred image with colour fringes around objects, especially noticeable in high-contrast scenes.
Cause: Light consists of various wavelengths (colours). Lenses bend (refract) light differently based on its wavelength. Shorter wavelengths (blue light) are bent more than longer wavelengths (red light).
Since, mirrors reflect light (not refract), so, chromatic aberration is present in lenses, not in mirrors. Reflection does not depend on the wavelength of the light, all colours of light are reflected uniformly.
Limits to reflecting telescopes:
A telescope with a higher limiting magnitude (Limiting magnitude is the brightness of the faintest object visible to an optical instrument) is required to look deep into the universe, which demands a larger primary mirror. However, there is a limit to the size of the primary mirror. A mirror wider than around 8.5 m will sink under its own weight, distorting its surface.
Hence, instead of a single primary mirror, today’s large reflecting telescopes have many small mirrors. Each piece is small enough to remain firm without slumping. And when they are combined, the overall light-collecting area (aperture) is still large. E.g., James Webb Space Telescope’s primary mirror is composed of 18 hexagonal segments. These segments work together to form a single, large mirror with a diameter of 6.5 metres.
Advanced telescopes around the world:
Large Binocular Telescope: The largest telescope to date is the Large Binocular Telescope (LBT), which has two 8.4-m-wide mirrors and an effective combined aperture of 11.9 m. It is located at the Mount Graham International Observatory in Arizona, USA.
Extremely Large Telescope: The Extremely Large Telescope (ELT) is under construction atop the Cerro Armazones in the Atacama Desert in Chile, as part of the European Southern Observatory. It has five mirrors and a combined aperture of 39.3 m. It is expected to be completed by 2028. The ELT’s light-gathering power will exceed that of any telescope to date. Our eyes can discern two lights burning 30 cm apart and kept 1 km away. In perfect conditions, the ELT can distinguish two lights kept 30 cm apart from 12,000 km away.
Subaru Telescope is an 8.2-m-wide Japanese telescope located at the Mauna Kea Observatory in Hawaii. It recently used 10 hours of exposure time to capture a faint celestial object with a visual magnitude of 27.7, which is 100-million-times fainter than what any human eye can detect.
James Webb Space Telescope (JWST): Launched in 2021 by NASA, JWST is orbiting the Sun at the L2 Lagrange point (1.5 million km from Earth). The infrared telescope has a 6.5 metre primary mirror. It detects near-infrared and mid-infrared wavelengths to observe faint and distant objects.
Why are telescopes setup on mountains?
The earth’s tumultuous atmosphere interferes with the telescope’s functioning. Telescopes are often set up on mountains for several key reasons:
Reduced Atmospheric Interference: At higher altitudes the atmosphere is thinner. The thinner atmosphere absorbs and scatters less light, improving the visibility of faint celestial objects.
Less Air Turbulence: Higher altitudes often experience less air turbulence compared to lower elevations, where weather systems can cause more turbulent air movement. This reduces blurring or distortion of images caused by atmospheric turbulence.
Space telescopes are more than 400 km above sea level, allowing them to entirely escape atmospheric disturbances. That is why the Hubble Space Telescope has a resolving power of around 0.04 arcsec, 10-times greater than the best ground-based telescopes.
Clearer Skies: Higher elevations generally have lower humidity levels, which means there is less water vapour in the atmosphere. This helps reduce cloud cover and atmospheric absorption, allowing for more frequent and prolonged observations.
Minimised Light Pollution: Mountain locations are often remote and away from large cities, which helps reduce light pollution and makes high-altitude locations ideal for clear, unobstructed observations.
Context: Mumbai-based Pharmaceuticals has announced that the Drug Controller General of India (DCGI) has approved its new eye drop, which has been “specifically developed to reduce dependency on reading glasses for individuals affected by presbyopia.”
About presbyopia:
It is an age-related condition in which the eyes gradually lose the ability to focus on nearby objects.
People usually start to develop presbyopia at around the age of 40.
The clear lens sits inside the eye behind the coloured iris. It changes shape to focus light onto the retina, allowing us to see objects. At a young age, the lens is soft and flexible, easily adjusting its shape, enabling people to focus on objects both near and far.
However, after the age of 40, the lens becomes more rigid and cannot change shape as easily, makes it harder to read, thread a needle, or perform other close-up tasks.
The common symptoms of presbyopia include blurred vision at normal reading distance and eye strain or headaches when performing tasks that require close focus.
It can be corrected with eyeglasses, contact lenses, medication, or surgery.
Context: Researchers have found that long COVID complications are not correlated with the severity of initial COVID-19. A person can have these complications even after mild or asymptomatic COVID-19 infection.
The study demonstrated a therapeutic strategy to manage COVID. A derivative of the 5B8 antibody has entered phase I clinical trials. If it completes this phase, it is likely to enter phase 2 where researchers will assess clinical endpoints.
SARS-CoV-2 Virus:
Coronavirus disease 2019 (COVID-19) is a highly contagious viral illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
SARS-CoV-2 is a novel beta coronavirus belonging to the same subgenus as the severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East Respiratory Syndrome Coronavirus (MERS-CoV).
It was first identified in December 2019 in Wuhan, China, and then caused a global pandemic leading to the COVID-19 pandemic.
Coronaviruses are positive-stranded RNA viruses with a crown-like appearance due to the presence of spike glycoproteins on the envelope.
Origin: Although the origin of SARS-CoV-2 is currently unknown, it is widely postulated to have originated from an animal, implicating azoonotic transmission.
Transmission: Exposure to respiratory droplets carrying the infectious virus from close contact or droplet transmission from pre-symptomatic, asymptomatic, or symptomatic individuals.
Mechanism of Transmission:
Entry into the Body: The SARS-CoV-2 virus is primarily transmitted through respiratory droplets or aerosols when an infected person coughs, sneezes, or talks. It can also spread via contact with contaminated surfaces. The virus typically enters the body through the nose, mouth, or eyes and travels down the respiratory tract.
Binding to Host Cell: SARS-CoV-2 has a characteristic spike protein (S protein) on its surface, which plays a critical role in infection. The spike protein specifically binds to a receptor on the surface of human cells known as ACE2 (Angiotensin-Converting Enzyme 2). These ACE2 receptors are found in high concentrations in the lungs, heart, kidneys, and intestines, which explains why the virus can affect multiple organs.
Fusion and Entry into the Host Cell:
After binding to the ACE2 receptor, the virus either:
Fuses with the cell membrane and releases its genetic material directly into the host cell, or
Enters the host cell through endocytosis, where the cell engulfs the virus, forming a vesicle that brings it inside.
This step is crucial for the virus to inject its RNA into the host cell, initiating the infection process.
Replication of Viral RNA: SARS-CoV-2 is an RNA virus. Once inside the cell, the virus releases its RNA, which hijacks the host cell’s machinery (ribosomes) to produce viral proteins and replicate the viral RNA. The host cell treats the viral RNA as if it were its own mRNA (messenger RNA), translating it into viral proteins like the spike protein, nucleocapsid, membrane proteins, etc.
Assembly of New Viruses: Newly made viral proteins and RNA molecules are then assembled into new viral particles (virions) within the host cell. These components come together in special compartments within the cell, like the endoplasmic reticulum and Golgi apparatus, to form complete new viruses.
Release of New Viruses: Once enough new virus particles are made, they are released from the infected host cell. These new viruses then infect nearby cells, spreading the infection throughout the body.
What is an antibody?
They are proteins produced by the immune system that neutralise any foreign substance (bacteria, virus) entering the human body.
An antibody attaches itself to an antigen – a foreign substance, usually a disease-causing molecule – and helps the immune system eliminate it from the body.
What is a monoclonal antibody?
Monoclonal antibodies are laboratory-made proteins that mimic the behaviour of antibodies produced by the immune system to protect against diseases and foreign substances.
Monoclonal antibodies are specifically designed to target certain antigens.
How do monoclonal antibodies work?
Monoclonal antibodies are specifically engineered and generated to target a disease. They are meant to attach themselves to the specific disease-causing antigen. An antigen is most likely to be a protein.
For example, most successful monoclonal antibodies during the pandemic were engineered to bind to the spike protein of the SARS-CoV-2 virus. The binding prevented the protein from exercising its regular functions, including its ability to infect other cells.
Context: Two NASA astronauts aboard Boeing's Starliner will remain on the International Space Station for an extended period due to a malfunctioning propulsion system, which has been plagued by helium leaks. Meanwhile, SpaceX's Polaris Dawn mission has faced delays due to helium-related problems with ground equipment. This issue with helium leaks is not unique; similar problems have impacted past missions, including ISRO's Chandrayaan 2 and ESA's Ariane 5.
Helium’s unique properties:
As the second lightest element after hydrogen, helium has an atomic number of 2 and is chemically inert-meaning it does not react with other substances or combust.
This makes it ideal for pressurization and cooling systems in rockets and spacecraft.
Inert gases:
An inert gas is a type of gas that resists reacting chemically with other substances.
These gases are less likely to form chemical compounds due to their low reactivity.
The primary function of inert gases is to prevent unwanted chemical reactions, such as oxidation and hydrolysis, which can degrade sensitive samples.
Typically, the term ‘inert gas’ includes:
Noble Gases: Helium, neon, argon, krypton, xenon, and radon.
However, the classification of gases as inert can be context-dependent.
While noble gases are generally considered inert due to their stable electron configurations, some of them, including nitrogen and carbon dioxide, can react under specific conditions.
Argon is the most frequently used inert gas. Its popularity is attributed to its high natural abundance (making up about 1% of the Earth's atmosphere) and its relatively low cost.
The non-reactivity of these gases is largely due to their complete valence electron shells, which contribute to their general stability.
Additionally, helium has an extremely low boiling point of -268.9°C, which allows it to remain in a gaseous state even in the extremely cold environments where rocket fuels are stored.
Importance in rocketry:
Achieving the requisite speeds and altitudes for rockets to reach and maintain orbit, demands highly precise and efficient fuel management.
Heavier rockets necessitate significantly more energy to achieve and sustain their trajectories. This increased energy demand leads to higher fuel consumption and requires more powerful engines.
The development, testing, and maintenance of these advanced engines are not only more complex but also more costly.
Helium is crucial in addressing these challenges due to its unique properties and essential functions:
Helium is used to pressurize fuel tanks, ensuring that fuel flows continuously and smoothly to the rocket’s engines throughout the mission. As the rocket’s fuel is consumed during flight, helium replaces the volume left behind, maintaining consistent pressure and preventing any interruptions in fuel delivery.
In addition to pressurizing fuel tanks, helium is integral to cooling systems, especially in environments where rocket fuels and oxidizers are stored at extremely low temperatures. Helium’s low boiling point ensures it remains a gas even in these frigid conditions, facilitating effective cooling and temperature management.
As fuel and oxidizers are depleted, helium fills the resulting voids in the tanks. This ongoing replenishment of helium helps maintain stable internal pressure, which is crucial for the efficient operation of the rocket’s fuel systems and overall performance.
Usage and safety:
Helium’s non-reactive nature makes it suitable for interacting safely with the residual contents in fuel tanks.
It is also employed in cooling systems to manage temperatures and prevent overheating.
Despite being non-toxic, helium can displace oxygen, making it unsuitable for breathing in high concentrations.
Prone to leaks:
Helium’s small atomic size and low molecular weight make it prone to escaping through small gaps or seals in storage tanks and fuel systems.
But because there is very little helium in the Earth’s atmosphere, leaks can be easily detected-making the gas important for spotting potential faults in a rocket or spacecraft’s fuel systems.
For instance, in May, shortly before Boeing’s Starliner was set to launch its first crewed mission, sensors detected a minor helium leak in one of the spacecraft’s thrusters. NASA assessed this leak as low-risk but it contributed to subsequent issues.
Additional leaks were detected in space after Starliner launched in June, contributing to NASA’s decision to bring Starliner back to Earth without its crew.
The frequency of helium leaks across space-related systems, have highlighted an industry-wide need for innovation in valve design and more precise valve-tightening mechanisms.
Alternatives and industry trends;
In response to helium-related challenges, some space missions have explored alternative gases such as argon and nitrogen, which are also inert and potentially less expensive.
However, helium remains the dominant choice due to its specific advantages.
A notable attempt to move away from helium was Europe’s new Ariane 6 rocket, which replaced the helium system of its predecessor, Ariane 5, with a novel pressurization system.
This system converts a small portion of its primary liquid oxygen and hydrogen propellants into gas for pressurizing these fluids.
Despite this innovation, the system experienced failure during the final phase of Ariane 6’s inaugural launch, illustrating the ongoing difficulties in achieving reliable pressurization systems without helium.
The Boeing Starliner, also known as CST-100, is a spacecraft developed to transport crew members to and from the International Space Station (ISS) and other low-Earth orbit destinations.
Designed under NASA's Commercial Crew Program (CCP), the spacecraft comprises a reusable crew capsule and an expendable service module.
Slightly larger than the Apollo command module or the SpaceX Crew Dragon, but smaller than the Orion capsule, the Starliner is capable of carrying up to seven astronauts.
The Starliner can remain docked to the ISS for up to seven months and is launched aboard an Atlas V N22 rocket.
The Crew Flight Test (CFT), launched in June 2024, encountered multiple malfunctions, including helium leaks and failures in five of the eight aft-facing reaction control system thrusters during its approach to the ISS.
Consequently, NASA deemed it too risky for returning astronauts to Earth on Starliner.
The uncrewed Starliner CFT-1 ultimately landed in September 2024.
Polaris Dawn:
Polaris Dawn is an upcoming private human spaceflight mission operated by SpaceX, commissioned by Shift4 CEO Jared Isaacman.
It is the first of three planned missions in the Polaris program, marking the 14th crewed orbital flight of a SpaceX Crew Dragon spacecraft.
The mission will carry a four-member crew.
The crew will be launched into a highly elliptical orbit, reaching up to 1,400 kilometers (870 miles) from Earth-the farthest human distance from Earth since NASA's Apollo program.
This trajectory will allow the crew to pass through portions of the Van Allen radiation belts, providing a unique opportunity to study the effects of space radiation and spaceflight on human health.
The Van Allen radiation belts are zones of energetic charged particles, primarily from the solar wind, trapped by Earth's magnetic field.
They form a barrier that prevents the most energetic electrons from reaching Earth.
The belts consist of two main regions:
Outer Belt: Contains high-energy particles from the Sun, trapped within Earth's magnetosphere.
Inner Belt: Formed by interactions between cosmic rays and Earth's atmosphere.
The belts were discovered in 1958 by American physicist James A. Van Allen using instruments on Explorer 1, the first U.S. spacecraft.
This discovery marked the beginning of space physics, as it revealed previously unknown radiation zones around Earth.
One of the key objectives of Polaris Dawn is to conduct the first-ever commercial spacewalk.
This mission not only aims to push the boundaries of private space exploration but also to advance scientific understanding of how the human body is affected by the unique conditions of deep space.
Chandrayaan-2:
Chandrayaan-2, is India's second lunar exploration mission, developed by the Indian Space Research Organisation (ISRO) after Chandrayaan-1.
The mission includes three components: a lunar orbiter, the Vikram lander, and the Pragyan rover, all designed and developed in India.
Its primary objective was to map the lunar surface, study its composition, and locate lunar water deposits.
The mission was launched in July 2019 from the Satish Dhawan Space Centre in Andhra Pradesh using a LVM3-M1 rocket.
Chandrayaan-2 entered in August 2019. An attempted landing by the Vikram lander in September 2019 failed due to a software error.
Despite the crash, the lunar orbiter continues to function in orbit around the Moon.
A subsequent mission, Chandrayaan-3, was launched in 2023 and achieved a successful lunar landing.
Ariane 6 is a European expendable launch vehicle developed by ArianeGroup for the European Space Agency (ESA) and operated by Arianespace.
It serves as the successor to the Ariane 5 within the Ariane launch vehicle family.
Ariane-5 Rocket has been used to launch ISRO’s communication satellites like GSAT-11, GSAT-30, GSAT-31, ESA’s Juice mission and NASA’s James Webb Space Telescope (JWST).
The rocket is a two-stage design that employs liquid hydrogen and liquid oxygen (hydrolox) as fuel.
The first stage is powered by an upgraded Vulcain engine from the Ariane 5, while the second stage is driven by the Vinci engine, created specifically for Ariane 6.
The rocket is available in two variants: Ariane 62, which includes two P120 solid rocket boosters, and Ariane 64, which uses four.
Chosen in 2014 over an all-solid-fuel alternative, Ariane 6 was finally launched in 2024.
The flight of Ariane 6 successfully placed nine cube-sats into orbit, including NASA's CubeSat Radio Interferometry Experiment (CURIE) and other satellites focused on studying Earth's climate and weather patterns.
The Vinci engine is capable of multiple restarts, enabling the deployment of payloads into several distinct orbits.
Context: Union Cabinet led by Prime Minister has approved the ‘BioE3’ (Biotechnology for Economy, Environment & Employment) Policy for Fostering High Performance Biomanufacturing of Department of Biotechnology under Ministry of Science & Technology.
Biomanufacturing
Biomanufacturing refers to the use of engineered microbial, plant and animal (including human) cells with increasing precision and control to produce commercially important products on scale.
Importance of Biomanufacturing in India
Biomanufacturing can transform from today’s consumptive manufacturing paradigm towards one based on regenerative principles and circularity. It will facilitate sustainable and efficient utilisation of biological resources.
It is particularly useful in sectors like specialty chemicals, enzymes, biopolymers, functional foods, smart proteins, veterinary products, precision biotherapeutics, services and carbon capture for addressing climate change.
Industrial biotransformation of specialty chemicals industry: Considering the global push towards sustainable manufacturing in the light of climate change, there is a huge scope for biotransformation of chemical processes. There is a need to drive industrial biotransformation, ensure sustainable bio-based production of high-value specialty chemicals, enzymes and biopolymers through synthetic biology and genetic engineering.
Smart proteins and functional foods: Bio-manufacturing tools like synthetic biology and metabolic engineering can address the nutritional deficiency problems by promoting alternative/smart proteins which include proteins from new sources (like plants, algae, fungi, insets) and from new approaches (like fermentation, plant-based meat or dairy, cultured meat etc.). These smart proteins and functional foods have low carbon footprint, low environmental impact, promote animal welfare and have better food safety.
Cell & Gene therapy: Advanced biomanufacturing will intensify India’s engagement in futuristic biotherapeutics techniques and personalized medicine such as cell & gene therapy, mRNA therapeutics, monoclonal antibodies. India has a potential to become global R&D and manufacturing hub for these technologies ensuring equitable access at scale.
Agricultural transformation: Bio-manufacturing can promote soil-microbiome based research & analysis, selection process of superior microbial phenotypes, process for shifting microbial community composition towards desired/most beneficial microbial consortia, developing crop specific products for crop nutrition & protection and product formulation for enhanced stability. Thus, bio-manufacturing can enhance agricultural productivity, ameliorate the impact of climate change, ensure food security, promote improved crop varieties.
Addressing Climate Change: India has a set a target of achieving ‘Net-Zero’ status by 2070. Advanced biomanufacturing can help achieve decarbonization of hard-to-abate industry sectors and microbial conversion of captured CO2 (carbon capture) into industrially relevant compound.
Blue Economy:India’s large coastline and the resultant marine bio-resources can be harnessed to power India’s bioeconomy, ease pressure on terrestrial land for food production and as a source for bioactive compounds, enzymes and functional ingredients.
Long-duration Space Nutrition: Considering the unique challenges of nutrition for astronauts in long duration missions, bio-manufacturing can provide integrated, safe and nutritious meals for remote, austere locations or future-long duration space missions having long shelf life, low waste generation, good quality and safety.
Objectives of BioE3 Policy
Intensifying research & innovation to address challenges such as mitigation of climate change and achieve decarbonization.
Place India at the forefront of global biomanufacturing solutions.
Boosting domestic biomanufacturing capability by enabling synergy between science, technology, engineering and manufacturing.
Accelerating transition to biomanufacturing by promoting integrated use of AI and digitalization of ‘omics and upstream biotechnology interventions.
Setting up facilities (biomanufacturing hubs/bio-fundary/bio-AI hubs) for scaling up and pre-commercial manufacturing, co-located with resources and infrastructure for fostering high-performance biomanufacturing.
Nurturing cohort of highly skilled workforce.
Harmonie regulatory reforms with global standards.
Effective and transparent patent system for use of genetic resources.
Promote sustainability in diverse ecosystems utilizing valuable knowledge of local communities.
Harness regenerative bioeconomy with ethical and biosafety considerations.
Salient features of BioE3 Policy
Focus on six thematic sectors: Government will focus on the following 6 thematic sectors to achieve technology leadership.
Bio-enablers: Bio-enablers are catalysts that will accelerate discovery and translation research to enable biomanufacturing across the above 6 identified thematic verticals:
Bio-Artificial Intelligence (Bio-AI) Hubs: Bio-AI hubs will bring together experts from computation and biological disciplines leading to integration of AI & biological data in fields such as genomics, proteomics and medical imaging. These fields hold great promise for:
Synthetic biology: ‘Omics’ data on microbial, fungal and algal strains can identify novel metabolic modules with predictive molecular design principles guiding synthetic biology approaches to biomanufacturer high-value chemicals and biomaterials.
Agriculture: Bio-AI hubs can provide data analytics to improve farming practices, soil conditions etc. leading to lower costs and increased productivity.
Biomanufacturing hubs: They will comprise common usage/shared infrastructure of pilot and pre-commercial manufacturing facilities for researchers, startups and SMEs to support early-stage manufacturing, enable development & demonstration of applications and transform research leads into commercial products.
Biomanufacturing Hubs will engage private sector partners to ensure sustainability in investments and for leveraging private sector operating capabilities.
These hubs will be accessible to all strategic central agencies on need basis for providing technological and upscaling support on targeted products and applications.
These hubs will attract and retain high-skilled workers, act as training centres for skilled manpower, generate jobs and provide positive economic ripple effect.
Regulation & Global Standards:
Regulations and global standards to be followed for creating an enabling environment for promoting R&D, scaling up and manufacturing, facilitating production and commercialization of novel bio-based products.
Regulations should be stringent considering the risks involved but ensure an increase in the pace at which products can reach the market.
This can be done by proactive engagement with all stakeholders, enhanced inter-ministerial co-ordination, seamless integration of biosafety & biosecurity considerations.
Building of a data governance framework to promote AI-based discovery and maximise public benefit from data usage.
Discoveries, inventions and other knowledge arising will be made freely available to wider scientific community, while allowing protection of intellectual property.
Use of fail-safe mechanisms for due acknowledgement of data sources while ensuring equitable access to data.
Strategies for boosting biomanufacturing in India:
Undertaking discovery & application oriented integrated network research for developing advanced biosynthetic platforms
Bridging gaps between lab & market and scaling up through effective industry-academia collaborations.
Reducing costs, time and complexity in biomanufacturing innovation ecosystem by co-locating
Setting up ‘bio-enabler hubs’ to accelerate discovery and translational research across prioritised sectors. ‘Bio-AI hubs’ will enable discovery research across sectors. ‘Bio foundries/Biomanufacturing Hubs’ will support facilities for pilot scale and pre-commercial scale research.
Creating a large skill-set pool of trained manpower in domestic biomanufacturing.
Addressing regulatory roadblocks for biomanufacturing of genetically modified organism-based resources.
Partnerships and collaborations with potential stakeholders to synergies investments in biomanufacturing like international partners, research institutions, universities, governments, private sector etc.
Public-Private Co-Creation Model will be used to implement with policy that combines expertise in academia, start-ups and industry through inter-ministerial coordination.
Context: In March 2025, Saturn's rings will briefly ‘disappear’ from view when observed from Earth. This phenomenon is an optical illusion caused by Saturn's tilt and orbital position.
An optical illusion:
Saturn's rings will not truly vanish, but they will appear to ‘disappear’ from Earth's view due to an optical illusion.
This illusion occurs because of Saturn's unique tilt and lengthy orbit around the Sun.
Saturn is tilted at an angle of 26.73 degrees and takes about 29.4 Earth years to complete a single orbit.
During this time, for approximately half of its orbit (around 15 Earth years), Saturn is tilted toward the Sun, and for the other half, it is tilted away.
Since Saturn's rings share the same tilt as the planet, their appearance changes as Saturn moves along its orbital path.
Every 13 to 15 years, the edge of Saturn’s rings aligns directly with Earth. This will happen in March 2025 when only the edges of the ring will be visible from our planet.
Since Saturn’s rings are very thin, just tens of metres thick in most places, at this position, they will reflect very little light, essentially making them invisible.
But as Saturn continues to go around the Sun, its rings will gradually reappear.
This phenomenon last occurred in 2009.
In 2018, NASA confirmed that Saturn is gradually losing its rings and will eventually be stripped of them entirely.
The rings are slowly being pulled towards the planet due to Saturn's gravitational and magnetic forces.
NASA described this phenomenon as ‘ring rain,’ estimating that an amount of water equivalent to that needed to fill an Olympic-sized swimming pool is drained from Saturn’s rings every half hour.
At this pace, Saturn could lose its rings completely within the next 300 million years, or potentially even sooner.
Data collected by NASA's Cassini spacecraft has shown that Saturn's rings consist of billions of ice and rock particles, ranging in size from tiny grains of dust to massive chunks as large as mountains.
While it is believed that other gas giants, such as Jupiter, Uranus, and Neptune, may have once had similar rings, today they possess only faint ringlets that are barely visible, even with powerful telescopes.
In contrast, Saturn's rings are expansive, stretching across a distance nearly five times the diameter of Earth. The rings are divided into seven major sections, each featuring a complex and intricate structure.
Saturn’s rings:
There are multiple theories regarding the origin of Saturn's rings:
Shattered Moon Hypothesis: One popular theory proposes that Saturn's rings are the remnants of a former moon that was shattered by a collision with a comet or another celestial body. The resulting debris then spread out and formed the rings.
Primordial Origin Hypothesis: Another theory suggests that the rings could have formed from material left over from the early solar system that never coalesced into a larger body. This leftover material could have been captured by Saturn’s gravity and eventually formed the rings.
Saturn's rings are a relatively recent feature of the solar system, believed to have formed around 100 million years ago.
Composition:
Saturn's rings are composed of a mix of icy particles, rocky debris, and dust. Despite their bright and stunning appearance from afar, these rings are surprisingly thin, with an average thickness of only about one kilometer.
The icy composition gives them their characteristic reflective sheen, allowing them to be visible from Earth.
Structure:
Saturn's rings are divided into several main groups, the most prominent of which are the A, B, and C rings.
These groups are separated by distinct gaps, such as the Cassini Division, which is a large, dark gap that divides the A and B rings.
The ring particles vary greatly in size, from tiny grains of dust to large chunks, and they orbit Saturn in a flat, disk-like structure.
Dynamics:
The structure and stability of Saturn's rings are influenced by the gravitational effects of several small moons, known as ‘shepherd moons.’
These moons, like Pandora and Prometheus, orbit near the rings and exert gravitational forces that help maintain the separation and sharp edges of the rings.
By constantly tugging on the ring particles, the shepherd moons prevent them from dispersing and help sustain the distinct formations we observe today.
Planet Saturn:
Saturn is the sixth planet from the Sun.
It is the second-largest planet in our Solar System, after Jupiter.
Saturn has a diameter of approximately 116,464 kilometers (72,366 miles).
The planet is thought to have a rocky core. This core is surrounded by a thick layer of metallic hydrogen, an intermediate layer of liquid hydrogen and helium, and an outer gaseous layer.
Saturn is known for its large and intense storm systems, such as the Great White Spot. This massive storm occurs roughly once every Saturnian year (about 29 Earth years). These storms can last for months and cover vast areas.
Saturn's rapid rotation gives it an oblate shape. It is flattened at the poles and bulging at the equator. Its equatorial radius (60,268 km) is over 10% larger than its polar radius (54,364 km). This shape causes gravity to vary; it is about 74% of that at the poles (8.96 m/s²), and the equatorial escape velocity is nearly 36 km/s, much higher than Earth's.
Saturn's average density is 0.69 g/cm³, making it the only planet less dense than water by about 30%. Its low density is due to its vast gaseous atmosphere.
Saturn and Jupiter together account for about 92% of the total planetary mass in the Solar System. While Jupiter has a mass 318 times that of Earth, Saturn is about 95 times more massive.
Saturn orbits the Sun at an average distance of 9.59 astronomical units (AU), or roughly 1,434 million kilometers. Its orbital period is about 29.45 Earth years, nearly three decades to complete one orbit.
Saturn has a system of at least 146 identified moons. Of these, 63 have been officially named. Titan, the largest, is notable for being larger (though less massive) than Mercury and is the only moon with a dense atmosphere and liquid hydrocarbon lakes.
Exploration of Saturn:
Saturn has been visited by four spacecraft. While the first three made flybys, Cassini-Huygens entered into orbit around the planet and deployed a probe to explore Titan’s atmosphere.
Pioneer 11:
Launch: 1973
Operator: NASA
Mission Type: Flyby
Outcome: Successful
Pioneer 11 was the first spacecraft to reach the Saturnian system, with its closest approach occurring in 1979.
It also discovered the moons Epimetheus and Janus.
Voyager 2:
Launch: August 1977
Operator: NASA
Mission Type: Flyby
Outcome: Successful
Voyager 1:
Launch: September 1977
Operator: NASA
Mission Type: Flyby
Outcome: Successful
Cassini-Huygens:
Launch: 1997
Carrier Rocket: Titan IV(401)B Centaur-T
Operators: NASA (United States) and ESA (European Union)
Mission Type: Orbiter and Titan Lander
Outcome: Successful
Cassini entered orbit around Saturn in July 2004, becoming the first spacecraft to do so.
It discovered seven new moons and conducted extensive studies of Saturn and its rings.
The Huygens probe, part of the mission, landed on Titan in January 2005, marking the farthest landing from Earth ever made by a spacecraft.
