The potential benefits of fusion energy are enormous. It could provide a nearly limitless supply of energy, reduce our reliance on fossil fuels, and help combat climate change
Imagine a world with a virtually unlimited source of clean energy that could power our cities, industries, and homes without the harmful emissions and environmental impacts of fossil fuels. This isn’t science fiction—it’s the promise of fusion energy. But what exactly is fusion energy, and how close are we to making it a reality?
Nuclear fusion involves combining light elements, such as hydrogen, to form heavier elements, releasing a significant burst of energy in the process. This process, which powers the heat and light of the Sun and other stars, is praised for its potential as a sustainable, low-carbon energy source.
This process contrasts with the nuclear fission process used in nuclear power plants, where heavy atomic nuclei are split into lighter ones. But this is fraught with radioactive waste and safety concerns.
The road to practical fusion energy is steep and fraught with challenges. The foremost obstacle is achieving and maintaining the extremely high temperatures and pressures required for fusion. Similar to those at the Sun’s core, these conditions are necessary to overcome the electrostatic forces that repel the positively charged atomic nuclei. For decades, scientists have experimented with different methods to achieve these conditions. The two primary approaches are magnetic confinement and inertial confinement.
Magnetic confinement, as seen in the tokamak design, employs powerful magnetic fields to contain hot plasma within a doughnut-shaped chamber. Inertial confinement, on the other hand, involves compressing a small pellet of fusion fuel with intense laser beams to achieve the conditions for fusion. Both methods have seen significant advancements but are yet to reach the break-even point, where the energy output from fusion equals the energy input required to sustain the reaction. However, recent breakthroughs have brought us closer than ever to this elusive goal.
The primary fuel for nuclear fusion is deuterium and tritium. Deuterium and tritium are isotopes of hydrogen, the universe’s most abundant element. Isotopes are members of a family of elements that all have the same number of protons but different numbers of neutrons. While all isotopes of hydrogen have one proton, deuterium has one neutron, and tritium has two, so their ion masses are heavier than those of protium, the isotope of hydrogen with no neutrons. Deuterium can be extracted from seawater, while tritium can be bred from lithium. When deuterium and tritium fuse, they form a helium atom, which has two protons and two neutrons, and release an energetic neutron. These energetic neutrons could serve as the foundation for generating energy in future fusion power plants.
Power plants today generate electricity using fossil fuels, nuclear fission, or renewable sources like wind or water. Regardless of the energy source, these plants convert mechanical power, such as the rotation of a turbine, into electrical power. In a coal-fired steam station, coal combustion turns water into steam, which then drives turbine generators to produce electricity.
The tokamak is an experimental machine designed to harness fusion energy. Inside a tokamak, the energy produced through atomic fusion is absorbed as heat by the vessel’s walls. Similar to conventional power plants, a fusion power plant will use this heat to produce steam, which then generates electricity via turbines and generators.
The international ITER project in France is the largest and most ambitious tokamak experiment to date. ITER aims to demonstrate the feasibility of fusion as a large-scale and carbon-free source of energy
At the core of a tokamak is a doughnut-shaped vacuum chamber. Under extreme heat and pressure inside this chamber, gaseous hydrogen fuel becomes plasma, creating an environment where hydrogen atoms can fuse and release energy. The plasma’s charged particles are controlled and shaped by large magnetic coils surrounding the vessel. This property allows physicists to confine the hot plasma away from the vessel walls. The term “tokamak” is derived from a Russian acronym for “toroidal chamber with magnetic coils.”
Image courtesy : EUROfusion
Fusion energy scientists consider tokamaks to be the leading plasma confinement design for future fusion power plants. In a tokamak, magnetic field coils confine plasma particles, enabling the plasma to reach the conditions necessary for fusion.
The international ITER project in France is the largest and most ambitious tokamak experiment to date. ITER aims to demonstrate the feasibility of fusion as a large-scale and carbon-free source of energy. It’s a collaboration involving 35 countries, including India, and is expected to produce first plasma in the coming years.
The primary objective of ITER is to investigate and demonstrate burning plasmas—plasmas where the energy from helium nuclei produced by fusion reactions is sufficient to maintain the plasma’s temperature, reducing or eliminating the need for external heating. ITER will also test the feasibility and integration of essential fusion reactor technologies, such as superconducting magnets, remote maintenance, and systems for exhausting power from the plasma. Additionally, it will validate tritium breeding module concepts that could enable tritium self-sufficiency in future reactors.
ITER made headlines just last year when it achieved a major milestone: the successful installation of its first-of-a-kind superconducting magnet system. This system is crucial for creating the powerful magnetic fields needed to contain the superheated plasma. This achievement brings us one step closer to achieving sustained fusion reactions.
On October 3, 2023, the Joint European Torus (JET) project in Oxford produced power for five seconds, resulting in a “ground-breaking record” of 69 megajoules of power. That energy was generated using only 0.2 milligrams of fuel.
An alternative method is inertial confinement fusion, where a compact fusion fuel pellet is compressed by high-powered lasers. The National Ignition Facility (NIF) in the United States is leading the way in this research. On December 5, 2022, the National Ignition Facility (NIF), located at the Lawrence Livermore National Laboratory in California, directed a series of lasers to emit 2.05 megajoules of energy towards a small cylinder containing a frozen pellet of deuterium and tritium, which are denser variants of hydrogen. The pellet underwent compression, resulting in the generation of temperatures and pressures of sufficient magnitude to induce fusion of the hydrogen contained inside it. During an extremely brief ignition, the merging atomic nuclei discharged 3.15 megajoules of energy, surpassing the amount of energy necessary to heat the pellet by approximately 50 percent. This stage is crucial in the journey towards the practical realisation of fusion energy production.
On October 3, 2023, the Joint European Torus (JET) project in Oxford produced power for five seconds, resulting in a “ground-breaking record” of 69 megajoules of power. That energy was generated using only 0.2 milligrams of fuel. In addition, many private companies are making waves in the fusion energy scene.
While these achievements are remarkable, there are still many technical hurdles to overcome. We need to improve the efficiency and durability of fusion reactors, develop materials that can withstand the extreme conditions inside them, and create systems for safely handling and breeding tritium.
Despite these challenges, the potential benefits of fusion energy are enormous. It could provide a nearly limitless supply of energy, reduce our reliance on fossil fuels, and help combat climate change. Imagine a world where energy is abundant, clean, and available to all—fusion energy could make this vision a reality. As we look to the future, the quest for fusion energy represents one of the greatest scientific and engineering challenges of our time. It’s a testament to human ingenuity and our unwavering determination to solve the world’s most pressing problems.
Dr Biju Dharmapalan is a science communicator and an adjunct faculty at the National Institute of Advanced Studies,Bangalore; formerly associated with Vigyan Prasar
The accretion of material from an evaporating second-generation giant planet accreting on a white dwarf star | Credit: Snehalata Sahu
A planet orbiting once every 4 days around a white dwarf star HS 0209+0832 – about 270 light years in the direction of the constellation Pisces – is steadily losing its atmosphere to its host star. While many stars in solar systems beyond our own often feed on their planets, this particular star feeds on its own ashes.
The gaseous planet HS 0209+0832 b was discovered in 2024, when the Transiting Exoplanet Survey Satellite, a NASA space telescope, found it orbiting the white dwarf star over the course of four days. The new study followed through with detailed observations from TESS data, NASA’s space-based Far Ultraviolet Spectroscopic Explorer, in addition to the ESO’s mountain-based Very Large Telescope, to study the star’s atmosphere and in turn inferring some chemistry occurring in the planet.
In a study published in the journal Nature Astronomy on Monday and funded by NASA, European Research Council, Fundación Occident and the Instituto de Astrofísica de Canarias, an international team of astronomers have reported imprints of niobium, a heavy element, in the atmosphere of a white dwarf star.
Astronomers predict the transiting young planet around the dead star is supplying that niobium back to its host. The sighting is evidence of a “second generation” planet, one of many candidates identified over several years, manifesting in a myriad different ways from spent gas ejected in the wake of stellar deaths.
It adds to a known coterie of planets now found orbiting dead stars, astronomers are busy studying to spot signs of life.
What are white dwarf stars?
White dwarves are an exotic stars, and are all that’s left off giant stars shedding their large gaseous skin in violent deaths. Our sun is destined one day to transform into a white dwarf, but only after swelling in size some five billion years from now to become a red giant when it will eclipse past the earth’s orbit. It would take several million years after that for the red giant sun to shed its gaseous exterior to become a white dwarf.
Planets if any, found orbiting these dead stars may have likely migrated from the new solar system’s outer reaches. All that’s left off the progenitor star’s past are imprints of light metals and other elements on the white dwarf’s atmosphere. Such planets have previously been spotted orbiting pulsars, a kind of neutron star, back in 1992. In fact, its discovery had marked the first ever detection of any planet orbiting a star beyond our sun.
Elements such as niobium don’t typically form in the core of stars like our sun. Chemical production usually limits to elements lighter than or until iron, with its 26 protons and 30 neutrons. Beyond that, slamming an extra proton or neutron will cause those to split, leaving iron to be the last element to be directly forged.
Niobium, with 41 protons and 52 neutrons, is thought to be born after absorbing slow passing neutrons when the red giant star dies to form a white dwarf star. This niobium hitches a ride along with rest of the contents of the red giant star, farther into the outer reaches of the system after the formation of the white dwarf.
These contents could create a new disc of circumstellar material with dust and gas that could condense one day to form new planets. The “second generation” planet found orbiting the white dwarf star from the new study, could have been born this way.
Alternatively, it may have been a planet in the outskirts like Neptune, migrating inwards, and enriching itself with niobium-rich star material.
Either way, the planet got too close to its host star, which is irradiating its newfound niobium-rich atmosphere, stripping it away and devouring it.
While it’s likely not a candidate planet for life as we know it to be found, it’s discovery can help ascertain how such worlds are formed in the aftermath of a star’s various phases of evolution.
Representational image of astronauts collecting lunar samples as international missions prepare for a new era of Moon exploration. Image credit: NASA
The Artemis Accords now have 76 signatories, expanding the international framework around the next phase of lunar exploration. For India, the milestone comes weeks after NASA invited the Indian Space Research Organisation (ISRO) to participate in its planned Moon Base programme.
Albania, Croatia, Côte d’Ivoire and San Marino joined the Accords in September, taking participation to 76 countries. NASA says nearly 40% of the world’s nations are now part of the framework, which sets principles for peaceful, transparent and responsible exploration of the Moon, Mars and beyond.
India became the 27th signatory in June 2023. At the India-US Civil Space Joint Working Group meeting in Bengaluru in August, NASA invited ISRO to participate in its Moon Base programme. The two countries also agreed to advance discussions on open scientific-data sharing under the Accords.
India is among the 76 countries that have signed the Artemis Accords, a framework for peaceful and responsible exploration of the Moon and beyond. Source: NASA
India’s Moon Base opportunity
The invitation does not specify what India will contribute. NASA has said every Artemis Accords signatory can participate through scientific payloads, technology demonstrations, CubeSats and other capabilities. Any specific Indian contribution would require further agreements.
India, however, is developing its own increasingly ambitious lunar programme. ISRO’s Chandrayaan-4 is planned as a lunar sample-return mission, designed to collect samples from the Moon’s polar region and bring them back to Earth. Chandrayaan-5/LUPEX, being developed with Japan’s JAXA, will study lunar polar volatiles in situ.
These missions could give India experience and scientific capabilities relevant to a future international lunar infrastructure.
ISRO Shaping the Data Conversation
Scientific data could be another area of Indian participation. In May 2026, ISRO led an initial Artemis Accords discussion on advancing open-data practices. NASA subsequently held two workshops focused on making lunar scientific data more accessible, interoperable and reproducible across countries.
That is significant as more lunar missions target the same regions. Shared standards could allow researchers to combine observations from different spacecraft instead of treating each mission’s data separately.
Moon – Space Coperation
India-US space cooperation is also expanding into human spaceflight. ISRO’s 2025–26 annual report records that Indian astronaut Shubhanshu Shukla travelled to the International Space Station in June 2025 as part of the Axiom-4 mission and conducted seven microgravity experiments. ISRO also held discussions with NASA on potential cooperation related to Gaganyaan.
The Artemis relationship therefore sits alongside an existing programme of India-US cooperation, including the NASA-ISRO Synthetic Aperture Radar (NISAR) mission.
What Changes for India?
The significance of the 76-country milestone lies in the network developing around it. The Artemis Accords cover scientific-data sharing, interoperability, non-interference between missions, emergency assistance and protection of historically significant lunar sites. NASA says signatories are now working through technical meetings and workshops to put these principles into practice.
For India, that creates several possible avenues: contributing technology or science to NASA’s Moon Base effort, sharing lunar data, and working with a growing group of countries on standards for increasingly crowded lunar operations. What India’s specific contribution to the Moon Base remains undecided. But with Chandrayaan-4, LUPEX and its human-spaceflight programme advancing alongside deeper NASA cooperation, India is entering the next phase of lunar exploration with its own capabilities already taking shape.
A dense field of stars, gas and dust surrounds the centre of the Milky Way in this infrared view from the James Webb Space Telescope. The region includes the environment around Sagittarius A* and nearby stars such as IRS 3. Image credit: ESA/Webb, NASA & CSA, F. Peißker, J. Lu, F. Yusef-Zadeh, N. B. Sabha, C. Chan
A dying star nearing the end of its life is shedding material into space just 0.55 light-years from the Milky Way’s central black hole. And somehow, some of that material is holding on. New observations from the James Webb Space Telescope have revealed water and oxygen-rich dust surrounding IRS 3, an evolved star living remarkably close to Sagittarius A*, the supermassive black hole at the heart of our galaxy.
The finding gives astronomers a rare view of what happens when an ordinary stage of stellar evolution unfolds in an anything-but-ordinary neighbourhood.
A Dying Star Beside a Black Hole
IRS 3 is an asymptotic giant branch (AGB) star, a late stage in the life of stars like this one. As such stars age, they swell, cool and lose material through powerful stellar winds. IRS 3 is doing exactly that. Gas and dust are streaming away from the star, creating a large envelope around it.
The star sits only about 0.55 light-years from Sagittarius A*. That may sound distant, but on the scale of the Galactic Centre it is remarkably close. Earth is about 26,000 light-years away from the same black hole.
A series of observations zooms from the Milky Way’s central region to IRS 3, the dying star located about 0.55 light-years from Sagittarius A*. The JWST infrared view reveals the crowded environment around the star and the Milky Way’s central black hole. Image credit: ESA/Webb, NASA & CSA, F. Peißker, J. Lu, F. Yusef-Zadeh, N. B. Sabha, C. Chan
Around Sagittarius A* is a crowded, energetic environment filled with intense radiation, dense gas and powerful gravitational forces. Astronomers have long wondered how stars manage to evolve and shed material there. IRS 3 is offering an answer.
Webb Finds Water in the Stellar Outflow
NASA‘s James Webb Space Telescope looked at IRS 3 using its Mid-Infrared Instrument, or MIRI. Infrared observations are particularly useful here because the dust surrounding the star glows strongly at these wavelengths.
The observations revealed oxygen-rich dust in the star’s envelope. They also produced the first detection of water in this material. This does not mean Webb found a pool, cloud or droplets of water. The water exists as molecules mixed into the hot gas and dust surrounding the star.
That distinction matters because molecules can be vulnerable in the harsh environment around the Galactic Centre. Radiation can break them apart, while the conditions around a supermassive black hole can affect the material being expelled by nearby stars. Yet water molecules are present around IRS 3.
The Star is Feeding Its Surroundings
IRS 3 is losing material rapidly as it approaches the end of its life. Researchers estimate that the star is shedding roughly the mass of Earth every 18 days. That enormous outflow is important beyond IRS 3 itself.
When evolved stars lose their outer layers, they return material to the space between stars. The gas carries elements produced during the star’s lifetime, while newly formed dust becomes part of the reservoir from which future cosmic structures can emerge. IRS 3 is therefore caught in a familiar cycle of stellar life: a star is dying, but the material it releases can become part of something else.
What makes this case unusual is that the recycling process is happening almost next door to a supermassive black hole.
How Much Can Survive Here?
The observation does not mean that the black hole has little influence on its surroundings. Sagittarius A* still creates an extreme environment, and the researchers are interested precisely because IRS 3 shows that stellar material can persist within it.
“Galactic centres are among the most extreme environments,” said Florian Peißker of the University of Cologne, the study’s lead author to media. With Webb, researchers can now examine the material around stars such as IRS 3 in much greater detail and ask how stellar winds, dust formation and molecular chemistry behave so close to a black hole. The answer emerging from IRS 3 is intriguing: the environment may be extreme, but it does not necessarily shut down the chemistry of a dying star.
For IRS 3, the end of its stellar life is already underway. Its outer layers are drifting away into the Galactic Centre, carrying dust, molecules and the chemical ingredients of future cosmic systems with them. Even in the shadow of the Milky Way’s central black hole, a dying star is still leaving something behind.