Comet Halley's Particles causes Meteor Shower visible till May 28

New Delhi, Jan 26: Google on Sunday marked India's 71st Republic Day by dedicating a doodle illustrating the country's rich cultural heritage that permeates and unites the diverse nation.

From its world-famous landmarks like the Taj Mahal and India Gate, to the wide array of fauna such as its national bird (the Indian peafowl), to classical arts, textiles, and dances, the doodle, designed by Singapore-based artist Meroo Seth, brings together the rich cultural heritage of the country.

Republic Day marks the completion of India's transition towards becoming an independent republic after its constitution came into effect. The governing document had taken nearly three years of careful deliberation to finalise, and its eventual enactment was joyfully celebrated across the country.

While the Constitution was adopted by the Indian Constituent Assembly on 26 November 1949, it came into effect on January 26 -- a day when Declaration of Indian Independence (Purna Swaraj) was proclaimed by the Indian National Congress back in 1929, as opposed to the Dominion status offered by the British Regime.

Festivities embody the essence of diversity found in one of the world's most populous nations, celebrated over a three-day period with cultural events displaying national pride.

Last year's doodle on Republic Day, designed by artist Reshidev RK, had featured Rashtrapati Bhavan in the background along with a display of the country's iconic monuments and heritage.

Mumbai, Jul 3: In yet another move to keep Chinese technologies companies at bay, the Centre has cancelled the 4G upgradation tender for BSNL as it has decided to come up with fresh specifications for the upgrade process, sources said.

The Department of Telecommunications (DoT) is likely to issue a fresh tender in the next two weeks.

People in the know said that the fresh tender may not allow Chinese companies to participate and that the new tenders that will be floated in the next two weeks will emphasise on Make in India.

As the border tussle with China escalated last month and around 20 soldiers lost their lives, the government had last month asked both BSNL and MTNL not to use equipment of Chinese makers in their upgrading process to 4G facilities.

Huawei and ZTE are the major Chinese telecom equipment makers working with Indian telecom companies and they would be the hardest hit by the decision.

The impact may be felt in terms of the much-awaited 5G trials in the country. After much deliberation, the Centre last December decided to allow Huawei to take part in the 5G trials.

The cancellation of tender for BSNL's 4G upgradation comes after the Centre on Monday banned 59 Chinese apps including TikTok, WeChat and UC Browser.

A statement by the Ministry of Electronics and IT said that the decision was taken since "there is credible information that these apps are engaged in activities which are prejudicial to sovereignty and integrity of India, defence of India, security of state and public order".

Leiden, Jul 2: Astronomers have discovered a luminous galaxy caught in the act of reionizing its surrounding gas only 800 million years after the Big Bang.

The research, led by Romain Meyer, PhD student at UCL in London, UK, has been presented at the virtual annual meeting of the European Astronomical Society (EAS).

Studying the first galaxies that formed 13 billion years ago is essential to understanding our cosmic origins. One of the current hot topics in extragalactic astronomy is 'cosmic reionization,' the process in which the intergalactic gas was ionized (atoms stripped of their electrons).

Cosmic reionization is similar to an unsolved murder: We have clear evidence for it, but who did it, how and when? We now have strong evidence that hydrogen reionization was completed about 13 billion years ago, in the first billion years of the universe, with bubbles of ionized gas slowly growing and overlapping.

The objects capable of creating such ionized hydrogen bubbles have however remained mysterious until now: the discovery of a luminous galaxy in which 60-100 percent of ionizing photons escape, is likely responsible for ionizing its local bubble. This suggests the case is closer to being solved.

The two main suspects for cosmic reionization are usually 1) a population of numerous faint galaxies leaking ~10 percent of their energetic photons, and 2) an 'oligarchy' of luminous galaxies with a much larger percentage (>50 percent) of photons escaping each galaxy.

In either case, these first galaxies were very different from those today: galaxies in the local universe are very inefficient leakers, with only <2-3 percent of ionizing photons escaping their host. To understand which galaxies governed cosmic reionization, astronomers must measure the so-called escape fractions of galaxies in the reionization era.

The detection of light from excited hydrogen atoms (the so-called Lyman-alpha line) can be used to infer the fraction of escaping photons. On the one hand, such detections are rare because reionization-era galaxies are surrounded by neutral gas which absorbs that signature hydrogen emission.

On the other hand, if this hydrogen signal is detected it represents a 'smoking gun' for a large ionized bubble, meaning we have caught a galaxy reionizing its surroundings. The size of the bubble and the galaxy's luminosity determines whether it is solely responsible for creating this ionized bubble or if unseen accomplices are necessary.

The discovery of a luminous galaxy 800 million years after the Big Bang supports the scenario where an 'oligarchy' of bright leakers emits most of the ionizing photons.

"It is the first time we can point to an object responsible for creating an ionized bubble, without the need for a contribution from unseen galaxies.

Additional observations with the upcoming James Webb Space Telescope will enable us to study further what is likely one of the best suspects for the unsolved case of cosmic reionization," said Meyer.