An international research team including Dr. Surhud More and Dr. Anupreeta More from Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune has ruled out the possibility of primordial black holes being a major constituent of dark matter using Subaru telescope. This finding disproves a theoretical claim of Prof Stephen Hawking. In the solar system, Mercury, the planet closest to the Sun, takes just 88 days to make one revolution around the sun, while Neptune, the farthest one, takes 165 years to make one round. In like manner, laws of gravity expect us to see stars closer to the centre of galaxies rotating faster than the stars on the edge.

The Union Cabinet has approved the Gaganyaan project under which a three-member crew will be sent to space for at least seven days, Union Minister Ravi Shankar Prasad stated. The project will cost INR 10,000 crore. The Gaganyaan project was announced by Prime Minister Narendra Modi in his Independence Day speech. He had stated that the mission will be undertaken by 2022. India has already inked agreements with Russia and France for assistance in the ambitious project.

According to a new collaborative study by the Queen's University Belfast and Aberystwyth University in the UK, the sun's magnetic field is ten times stronger than previously thought. Using the Swedish one-metre Solar Telescope at Roque de los Muchachos Observatory, in the Canary Islands, David Kuridze studied a particularly strong solar flare which erupted near the surface of the Sun on September 10, 2017. A combination of favourable conditions and an element of luck enabled the team to determine the strength of the flare's magnetic field with unprecedented accuracy. The researchers believe the findings have the potential to change our understanding of the processes that happen in the Sun's immediate atmosphere. The study found that the sun's corona extends millions of kilometres above the surface, measuring 1,400,000 kilometres across -- 109 times larger than Earth and 150,000,000 km from Earth. Solar flares appear as bright flashes and occur when magnetic energy that has built up in the solar atmosphere is suddenly released.

Chang'e-4 lunar probe, a Chinese space probe, touched down on the far side of the moon. The probe, which has a lander and a rover, that was launched in December made the soft landing and transmitted the first-ever close-range image of the far side of the moon. It touched down at a targeted area near the moon's south pole in the Von Karman Crater. The purpose of the Chang'e-4 includes astronomical observation, surveying the moon's terrain, landform, and mineral makeup, and measuring the neutron radiation and neutral atoms to study the environment of its far side. The moon is tidally locked to Earth, rotating at the same rate as it orbits our planet, so most of the far side or dark side is never visible to us. Previous spacecraft have seen the far side, but none has landed on it. China's space agency hailed the event as a historic first and a major achievement for the country's space programme.

Cricket Australia have added seven-year-old Archie Schiller in the 15-member squad for the third Test of the series against India, at the Melbourne Cricket Ground (MCG) on Boxing Day, December 26. He was co-captain alongside Tim Paine. Archie Schiller, who has endured 13 heart operations and spent half of his life in hospital after being diagnosed with a life-threatening congenital disease, had the dream of captaining the Australian cricket team. Make a Wish Australia and Cricket Australia, worked together to make Archie's cricket dreams come true.

India successfully test fired the short range Quick Reaction Surface-to-Air Missile (QRSAM), developed by the Defence Research and Development Organisation (DRDO) for the Indian Army, from a test range along the coast of Odisha. It is a sleek and highly mobile air defence system with a strike range of 25 km to 30 km and has a capability of engaging multiple targets. It is different from normal air defence system, as this is an all-weather, all-terrain missile with electronic counter measures against jamming by aircraft radars. It was first tested in June 2017 and followed by the second successful test in July 2017. It will replace the 'Akash' missile defence system which is on its way out due to technological obsolescence.

Light Combat Aircraft (LCA) Tejas progressed towards manufacture in an enhanced, battle standard format on December 31. The LCA is being designed and developed by the Aeronautical Development Agency (ADA) in Bengaluru. A new limited clearance from military airworthiness certifier CEMILAC for the Indian fighter green-lights its production in a superior lethal version. HAL aims to get the first aircraft out in late 2019. The Indian Air Force (IAF) has asked Hindustan Aeronautics Limited (HAL) to make 40 LCA aircraft. Of this, 20 will be in the advanced Final Operational Clearance (FOC) format. Another 20 are in the earlier Initial Operational Clearance (IOC) version. The IAF has modified and upgraded its trainer requirement in its old package order of 40 LCA aircraft.

The first nuclear test Pokhran with a codenamed as 'Smiling Buddha' was carried out in May 1974. The second test conducted was Pokhran II which was a series of five tests of nuclear bomb explosions, administered by India at the Pokhran Test Range of Indian Army in May, 1998. Pokhran II comprised of five detonations out of which the first one was a fusion bomb while the other four were fission bombs. These nuclear tests evolved various sanctions against India by many major states, including the United States and Japan.

The National Aeronautics and Space Administration (NASA)'s Hubble Space Telescope ejected measurements validate that the Universe is expanding about 9% faster than expected based on its trajectory seen shortly after the big bang. It was published in Astrophysical Journal Letters on April 25.The researchers using Hubble as a "point-and-shoot" camera to look at groups of Cepheids using a new method called DASH (Drift And Shift), while Hubble can observe one star for every 90-minute orbit around Earth.Adam Riess, Bloomberg Distinguished Professor of Physics and Astronomy at The Johns Hopkins University, Nobel Laureate and the project's leader,is the first author of the research.

Board of Control for Cricket in India (BCCI) announced cash awards of Rs 15 lakh per match for each of the playing eleven that featured in India's maiden Test Cricket series win on Australian soil. Virat Kohli and his team defeated Australia 2-1 in the four-match Test series, ending India's 71-year-old wait for the rare achievement. Congratulating the team, the BCCI also announced cash awards of seven and a half lakh rupees for all the reserve players, as well as the members of the support staff.