Joint Lunar Polar Exploration (LPE)

• Joint mission between Japan Aerospace Exploration Agency (JAXA) and ISRO in 2017.
• To put a lander and a rover on the Moon’s surface.
• It will be launched after 2023.
• Target: constantly sunlit region near Moon’s South Pole.

Moon’s South Pole

• Its craters are untouched by sunlight.
• The permanently shadowed craters hold millions of tons water.
• Offers an undisturbed record of solar system’s origins.
• It has an untapped source of resources.


NASA’s missions to Mars

• Mars Pathfinder Mission (1997)
• Spirit and Opportunity (2003)
• Curiosity (2012)
• Mars 2020
   o Perseverance rover: It will land in Jezero Crater on Mars.
   o MOXIE or Mars Oxygen ISRU Experiment instrument: for the        first time, it will manufacture molecular oxygen on Mars.
   o Ingenuity Mars Helicopter: first aircraft to attempt         controlled flight on another planet.

Tianwen 1 or Quest for Heavenly Truth 1

• China’s first Mars probe
• Orbiter: for comprehensive observation
• Lander: on Martian soil
• Rover to roam the landing site.
• Yinghuo-1, 2011: China’s failed attempt of an exploratory probe to Mars called, in a Russian spacecraft.
• US, Russia, EU and India have so far succeeded in sending missions to Mars.
• India is the first country to enter the Martian orbit in its first attempt.

Mars moons: Phobos and Deimos

• Phobos, the closest and biggest moon of Mars.
• Craters on Phobos- Stickney, Shklovsky, Roche & Grildrig.


  • A large volcanic province on Mars.

Light Detection And Ranging (LiDAR or LADAR)

  • It is a method for measuring distances (ranging) by illuminating the target with laser light and measuring the reflection with a sensor.
    • A lidar instrument consists of a laser, a scanner, and a specialized GPS receiver.
    • It is similar to radar and sonar, that uses radio and sound waves, respectively.
    • Lidar is also called 3-D laser scanning, a special combination of a 3-D scanning and laser scanning.
    • Differences in laser return times and wavelengths can then be used to make digital 3-D representations of the target.

Quantum Technology

• Quantum technology uses laws of quantum physics.
• It describes the behaviour of matter and energy at atomic and subatomic level.
• It is based on properties of quantum mechanics, especially quantum entanglement, quantum superposition and quantum tunnelling.
• According to John von Neumann, quantum technology is different from the deterministic classical mechanics, which holds that the state is determined by values of two variables.
o Quantum technology is determined by probabilities. and this explanation has been used to justify the technology’s superiority.
o This is unlike classical physics, where an object can exist at one place at one time.
o E.g. classical computers operate using binary physical state, meaning its operations are based on one of two positions (1 or 0).
• Superposition: each qubit can represent both a 1 and a 0 at the same time.
• Quantum entanglement: subatomic particles are inextricably linked or entangled in such a way that any change in one disturbs the other, irrespective of their distances.
• Quantum tunnelling: A quantum mechanical phenomenon where a wavefunction can propagate through a potential barrier.

Quantum Supremacy

• A quantum computer can do a mathematical calculation that is beyond the reach of even the most powerful supercomputer.
• Sycamore: Google’s quantum computer. It performed a calculation in 200 seconds.
• Summit: world’s fastest supercomputer. It can do same calculation in 10,000 years.

Micius, 2016

  • China’s quantum It is world’s first quantum-enabled satellite.
  • Also known as Quantum Experiments at Space Scale (QUESS), which is Chinese research project in quantum physics.
  • Micius sent first totally secure long-range message using Quantum Key Distribution (QKD).
  • Hacking is not possible: Quantum Satellite produces pairs of entangled photons, twinned light particles whose properties remain intertwined irrespective of their distance.

Quantum Key Distribution (QKD)

  • It allows secure encrypting and decrypting
  • In traditional cryptography, security is usually based on a
  • QKD secures by the laws of quantum physics – superposition and

Lithium in Stars

  • In process of evolution, stars destroy lithium as they evolve into red giants.
  • Planets have more lithium than their stars. Eg. Earth-Sun pair.
  • However, some stars are lithium-rich.
  • Lithium in the universe is only four times the original Big Bang Other elements grew millions of times.
  • Helium flash: occurs at late stage of a star’s evolution.
    • Helium accumulates at its core. It causes temperature and pressure to This stage is known as Red Clump stage.
    • when stars grow beyond their Red Giant stage into the Red Clump stage, they produce lithium in what is known as a Helium Flash.


  • News: Recently, Indian Institute of Astrophysics (IIA), under the Department of Science and Technology discovered hundreds of Lithium (Li) rich giant stars.


  • A red giant star is a dying star in the last stages of stellar evolution.
  • Lithium is one of the three primordial elements produced in the Big Bang Nucleosynthesis. Others are Hydrogen and Helium.

Extreme Helium Star (EHe)

  • An EHe or a PV Telescopii Variable, is a low-mass supergiant that is almost devoid of hydrogen, the most common chemical element of the Universe.
  • It has abundance of surface
  • Majority of stars contain 70% hydrogen by mass.
  • These are much larger and hotter than
  • There are no known conditions where stars devoid of hydrogen can be formed from molecular clouds, it is postulated that they are product of the mergers of helium-core and carbon-oxygen core white dwarfs.

Coronal seismology or magneto seismology

  • Used to measure the magnetic field of Sun’s corona for the first
  • This method uses magnetic waves or Alfven waves, that can travel along with the magnetic
  • Till now, solar magnetic fields were measured only at Sun’s surface (photosphere).
  • Note: Corona is the outermost layer of the Sun’s atmosphere, consisting of hot, diffuse, and highly ionized plasma.

South Atlantic Anomaly (SAA)

  • Also called as ‘dent’ in Earth’s Magnetic Field.
  • It is an unusually weak spot in the Earth’s Magnetic Field
  • SAA is the near-Earth region where the Earth’s magnetic field is weakest relative to an idealized Earth-centered dipole field.
  • Causes of formation: tilt of earth’s magnetic axis, and flow of molten metals within earth’s outer
  • SAA allows charged particles from Sun to dip closer to the Earth’s surface.


  • Recent data from NASA shows splitting of South Atlantic Anomaly.
  • SAA is expanding westward and splitting into two lobes which can result in weakening of magnetic field.
  • Low-Earth orbit satellites travel through SAA. Solar particles can hit them and create short circuit.


Indian National Space Promotion and Authorization Centre (IN- SPACe)

  • Aim: to boost private sector participation in entire range of space activities.
  • It is the new entity of the Department of Space
  • To act as an interface between ISRO and private parties
  • It will be autonomous, and parallel to
  • It is the second space organisation created in last two years.
    • New Space India Limited (NSIL) was announced in 2019 Budget.

India’s First In- orbit Space Debris Monitoring and Tracking System

  • To provide real-time earth coverage by deploying a constellation of cost-efficient nanosatellites in Low Earth Orbit.
  • Developed by Digantara, India’s first air and space surveillance company.

Moon is more metallic than thought before

  • Study by NASA’s Lunar Reconnaissance Orbiter (LRO)
  • Moon’s subsurface might have more metals such as iron and titanium.
  • This may mean Earth’s crust has lesser amounts of iron oxide than the
  • This questions most popular theory about the Moon’s creation
    • A Mars-sized protoplanet collided with newly formed Earth
    • Breaking off a piece of our planet
    • It went on to become its satellite.

ASTHROS: a telescope in balloon

Astrophysics Stratospheric Telescope for High Spectral Resolution Observations at Submillimeter- wavelengths

  • NASA’s mission to send a balloon telescope into stratosphere
  • To observe wavelengths of light invisible from the
  • To be launched in 2023 from Antarctica.

Lunar Gateway, NASA

  • Also known as Gateway lunar orbiting outpost
  • It is a planned Moon space station in lunar orbit.

Objective: To serve as a communication hub, science laboratory, habitation module, holding area for rovers etc.

Comet NEOWISE (C/2020 F3)

  • Spotted by NASA’s (NEOWISE) telescope
  • Comets are dusty snowballs which orbit the Sun.
  • NEOWISE telescope: Near-Earth Object Wide-field Infrared Survey Explorer.

Potentially Hazardous Asteroids (PHAs)

  • Asteroids with a MOID distance of 05 AU, and bigger than 150 meters diameter are considered PHAs.
  • minimum orbit intersection distance (MOID): It is the distance between the closest points of the overlapping orbits of two bodies.
  • Astronomical unit (AU): It is the distance between Earth and Sun and is roughly 150 million

News: Asteroid 2020 ND made a fly-past the Earth.

  • NASA classified it as a PHA and as a Near Earth Object (NEO).


Ceres given status of an “ocean world”

  • Ceres has a brine reservoir. e. solution of salt in water.
  • It is a Dwarf Planet.

Andromeda Galaxy (or Messier 31, M31)

  • It is a barred spiral galaxy approximately 2.5 million light-years from Earth and the nearest major galaxy to the Milky Way.
  • The virial mass of the Andromeda Galaxy is of the same order of magnitude as that of the Milky Way, at 1 trillion solar masses (2.0×1042 kilograms).
  • News: NASA’s Hubble Space Telescope mapped immense envelope of gas (halo), surrounding it.

Space bricks for lunar habitation

  • IISc and ISRO developed a sustainable process for making brick-like structures on the moon.
  • It exploits lunar soil, bacteria, urea from human urine and guar beans to consolidate the soil into possible load-bearing structures.
  • Could be used to assemble structures for habitation on the moon’s surface.

SPT0418-47 galaxy

  • It is a young, extremely distant galaxy.
  • Discovered in 2020, surprisingly similar to the Milky Way
  • It is surprisingly non-chaotic and contradicts the theory that all galaxies in the early Universe were turbulent and unstable.
  • A galaxy is a large group of stars, gas, and dust bound together by gravity.

AEHF 6 satellites, USA: Advanced Extremely High Frequency

  • A series of six military communication satellites for U.S. Space Force.
  • US space force was established as separate military branch in 2019.

Arktika-M satellites, Russia

  • for monitoring Arctic climate.

Xingyun-2, China

  • Communications satellites for space-based Internet-of-Things project.
  • Note: The Internet of Things (IoT) describes the internet network of physical objects—“things”, that are embedded with sensors, software, and other technologies for connecting and exchanging data with other devices and systems over the internet.

DART Mission, NASA

DART: Double Asteroid Redirection Test

  • Proposed mission to prevent Earth by a hazardous asteroid impact.
  • Uses kinetic impactor technique: to change the motion of an asteroid in space.
  • Target: Binary near-Earth asteroid Didymos.

SunRise Mission, NASA

  • Sun Radio Interferometer Space Experiment
  • To study the mechanism of solar storms.
  • Solar storms are eruptions of mass and energy from the solar surface such as flares, coronal mass ejections etc.

DEMO-1 mission, SpaceX

  • SpaceX’s first un-crewed test flight to International Space Station in 2019.

DEMO-2 Mission, NASA

  • To send astronauts to International Space Station (ISS) on SpaceX’s Crew Dragon spacecraft.
  • It will use a Falcon 9 rocket built by SpaceX.
  • NASA is planning to use SpaceX and Boeing companies to travel the International Space Station.
  • Note: NASA’s Space Shuttle fleet retired in 2011. Since then, Russian Soyuz spacecraft is the sole means of human transport to the ISS.

Artemis, NASA

A mission to land the first woman on Moon.

Cislunar space

  • Space between earth and moon.

Artemis Accords for Responsible Space Exploration

  • A series of bilateral agreements between NASA and its international partners.
  • To create common set of principles to govern the civil exploration
  • It is based on Outer Space Treaty, 1967.
  • India is not a partner yet.

OSIRIS-Rex, 2016 - NASA

  • Origins Spectral Interpretation Resource Identification Security – Regolith Explorer
  • It is a NASA spacecraft to near-Earth asteroid, Bennu.
  • Will bring sample back to Earth.

Cassini mission

  • By NASA, ESA and the Italian space agency.
  • Spacecraft to Saturn
  • Huygens probe: landed on surface of Saturn’s largest moon, Titan.


ANITA: Antarctic Impulsive Transient Antenna

First NASA observatory for neutrinos, a radio telescope designed to detect ultra-high energy cosmic-ray neutrinos from a scientific balloon flying over the continent of Antarctica.


  • They carry no electrical charge and are nearly massless.
  • They hardly interact with matter: hence, are least harmful of elementary particles.
  • Lepton family: Neutrinos and antineutrinos belong to this. It means they do not interact via strong nuclear force.
  • These are second most abound particles in the universe.
  • 3 types or flavors: based on mass: electron-neutrino, muon-neutrino, tau-neutrino).
  • Produced in the core of the sun
  • Can also be made artificially in radioactive decays and in nuclear reactors.


  • They are antiparticles of neutrinos.
  • Produced in the negative beta decay.
  • These can also pass through Earth without any interaction.

 Neutrino study projects

  • LAGUNA, Europe
  • Hyper Kamiokande Detector,
  • DUNE,
  • India-based Neutrino Observatory (INO): proposed in Theni district in Tamil Nadu.
  • China also proposed.

Black hole

  • A region of spacetime where gravity is so strong that nothing can escape from it. Not even electromagnetic radiation such as light.
  • The gravity is so strong because matter has been squeezed into a tiny space.
  • The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.
  • In many ways, a black hole acts like an ideal black body, as it reflects no light.
  • Event horizon: The boundary of the region from which no escape is possible.
    • But, it has no locally detectable features.
    • It emits Hawking radiation with the same spectrum as a black body of a temperature inversely proportional to its mass.
    • This temperature is on the order of billionths of a kelvin, making it essentially impossible to observe.
  • Black holes form when a star with a mass greater than three times that of our sun runs out of fuel.
    • It explodes into a supernova and collapses into an extremely dense core or a black hole.
  • Albert Einstein theorized Black holes in 1915.
  • In 2019, NASA released first ever photograph of black hole captured by Event Horizon Telescope.

Primordial Black Holes

  • A hypothetical type of black hole that formed soon after the Big Bang.
  • Formed because of collapsing radiations as opposed to collapse of massive stars, which is case of any other black holes.

Binary Black Hole

  • A system consisting of two black holes in close orbit around each other.
  • When their merger happens, immense energy is released as gravitational waves.
  • All discoveries of BBH mergers, till now, involved Black Holes of comparable masses.
  • GW190412 BBH merger: first observation where two black holes of different masses merged.

Gravitational Waves

  • These are ‘ripples’ in space-time (disturbances in the curvature of spacetime), that propagate as waves outward from their source at the speed of light.
  • Cataclysmic origins
  • Caused by some of most violent and energetic processes in Universe.
    • Accelerated masses,
    • When a star explodes asymmetrically (called a supernova)
    • When two big stars orbit each other,
    • When two black holes orbit each other and merge
  • First detected in 2015 by Laser Interferometer Gravitational Wave Observatory (LIGO), USA.
  • Proposed by Henri Poincaré in 1905.
  • Predicted in 1916 by Albert Einstein on the basis of general theory of relativity.
  • These transport energy as gravitational radiation, a form of radiant energy similar to electromagnetic radiation.
  • Newton’s law of universal gravitation, part of classical mechanics, does not provide for their existence.

Solar cycle or Sun Spot cycle or solar magnetic activity cycle

  • Sun goes through 11-year cycles of activity that peak & trough with a Solar Maximum and a Solar Minimum.
  • So far, 24 such cycles are documented.
  • 25th cycle has just begun.
  • At Solar Maximum, Sun’s surface has maximum activity. Eg. sun spots, solar flares etc.
  • Solar minimum: sunspot and solar flare activity diminishes.
  • News: Sun has gone into Solar Minimum phase.

Sun Spots

  • These are temporary phenomena on the Sun’s photosphere that appear as spots darker than the surrounding areas.
  • They are regions of reduced surface temperature.
  • Formed where magnetic fields are so strong that they keep some of the heat within the Sun from reaching the surface.
  • due to concentrations of magnetic field flux that inhibit convection.
  • Sunspots usually appear in pairs of opposite magnetic polarity.
  • Their number varies according to 11-year solar cycle.

Maunder minimum

  • Also known as “prolonged sunspot minimum”
  • The period around 1645 to 1715 during which sunspots became exceedingly rare.
  • This coincided with extremely cold weather on earth.


  • These are the planets that orbit around stars other than the Sun.
  • Hard to detect with telescopes: as they are hidden by bright glare of their orbiting star.


  • Kepler-1649c: Earth-size exoplanet discovered from NASA’s Kepler space telescope.
    • It orbits a red dwarf star: these stars are known for stellar flare-ups.
  • Super earth: Earth-size exoplanet discovered at the centre of our galaxy.
    • Denser than
  • K2-18 b: It orbits a red dwarf star in the Leo constellation.
  • WASP-76 b: liquid iron rain was spotted.

Fomalhaut B

  • Earlier it was considered as an exoplanet.
  • This is a giant cloud of dust left over from the collision of two planetesimals that dispersed over time.
  • Discovered by NASA’s Hubble Space Telescope.