'Digital drive puts India at greater cyber attack risk'

Paris, Jul 2: Several interacting exoplanets have already been spotted by satellites. But a new breakthrough has been achieved with, for the first time, the detection directly from the ground of an extrasolar system of this type.

An international collaboration including CNRS researchers has discovered an unusual planetary system, dubbed WASP-148, using the French instrument SOPHIE at the Observatoire de Haute-Provence (CNRS/Aix-Marseille Universite).

The scientists analysed the star's motion and concluded that it hosted two planets, WASP-148b and WASP-148c. The observations showed that the two planets were strongly interacting, which was confirmed from other data.

Whereas the first planet, WASP-148b, orbits its star in nearly nine days, the second one, WASP-148c, takes four times longer. This ratio between the orbital periods implies that the WASP-148 system is close to resonance, meaning that there is enhanced gravitational interaction between the two planets. And it turns out that the astronomers did indeed detect variations in the orbital periods of the planets.

While a single planet, uninfluenced by a second one, would move with a constant period, WASP-148b and WASP-148c undergo acceleration and deceleration that provides evidence of their interaction.

The study will shortly be published in the journal Astronomy & Astrophysics.

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.

New Delhi, Jun 18: Vodafone Idea on Thursday told the Supreme Court that it has incurred Rs 1 lakh crore losses as it insisted it is not in a position to furnish bank guarantees.

A bench comprising Justices Arun Mishra, S. Abdul Nazeer, and M.R. Shah, taking up the adjusted gross revenue (AGR) matter through video conferencing, directed the telecom companies to submit their financial documents and books for the last 10 years.

Asking Vodafone if it was a foreign company, the bench said that how can the company say it would not furnish any bank guarantee.

"What if you fly away overnight in future without paying anything?" it asked.

Senior advocate Mukul Rohatgi, representing Vodafone Idea, denied his client is a completely foreign firm and cited before the bench its tie-ups and investments.

Vodafone owes over Rs 58,000 crore as AGR dues and so far, has paid close to Rs 7,000 crore.

Rohatgi contended before the court that the telecom company is in a tough situation, and cannot furnish any fresh bank guarantee, as profits have eluded the company in past many quarters. He submitted before the bench that Rs 15,000 crore bank guarantees are lying with the government, and his client's losses are over Rs 1 lakh crore.

"I cannot offer any more surety," he informed the bench.

Justice Mishra noted that this is public money and these dues should be recovered. "Do not tell us that you will pay if you were to make profits... the money must come," he noted.

Justice Shah observed that the telecom industry is the only industry which earned during the Covid-19 pandemic. "After all, this money will be used for public welfare", he said.

Rohatgi argued that his client would have to fold up if orders were issued to clear dues tomorrow. "11,000 employees will have to go without notice, as we cannot pay them," he added.

Senior advocate Abhishek Manu Singhvi, appearing for Bharti Airtel, contended before the court that out of Rs 21,000 crore AGR dues, the company has already deposited a sum of Rs 18,000 crore.

He argued that his client has given a bank guarantee, in excess of demand, to DoT, and supported the proposal for phased repayment of remaining AGR dues. He insisted that the company needs to sit down with the government and calculate the dues. Airtel owes Rs 25,976 crore after paying Rs 18,000 crore, as per the government.

Senior advocate Arvind Datar, representing Tata Telecom, informed the bench that his client has paid Rs 6,504 crore in AGR dues so far, and furnishing a bank guarantee may adversely impact investments in the sector.

The total AGR dues are close to Rs 1.5 lakh crore.

The top court will now take up the matter in the third week of July.