Google shuts free public Wi-Fi at railway stations in India

In a study conducted in 117 countries, researchers have found that the world is experiencing the most dramatic reduction in the seismic noise (the hum of vibrations in the planet's crust) in recorded history due to global COVID-19 lockdowns.

Measured by instruments called seismometers, seismic noise is caused by vibrations within the Earth, which travel like waves and the waves can be triggered by earthquakes, volcanoes, and bombs - but also by daily human activity like travel and industry.

This quiet period was likely caused by the total global effect of social distancing measures, closure of services and industry, and drops in tourism and travel, the study published in the journal Science, reported.

The new research, led by the Royal Observatory of Belgium and five other institutions around the world including Imperial College London (ICL), showed that the dampening of 'seismic noise' caused by humans was more pronounced in more densely populated areas.

"Our study uniquely highlights just how much human activities impact the solid Earth, and could let us see more clearly than ever what differentiates human and natural noise," said study co-author Stephen Hicks from ICL in the UK.

For the findings, the research team looked at seismic data from a global network of 268 seismic stations in 117 countries and found significant noise reductions compared to before any lockdown at 185 of those stations.

Researchers tracked the 'wave' of quietening between March and May as worldwide lockdown measures took hold.

The largest drops in vibrations were seen in the most densely populated areas, like Singapore and New York City, but drops were also seen in remote areas like Germany's the Black Forest and Rundu in Namibia.

Citizen-owned seismometers, which tend to measure more localised noise, noted large drops around universities and schools around Cornwall, UK and Boston, US - a drop in noise 20 per cent larger than seen during school holidays.

The findings showed that countries like Barbados, where lockdown coincided with the tourist season, saw a 50 per cent decrease in noise.

"The changes have also given us the opportunity to listen in to the Earth's natural vibrations without the distortions of human input," the study authors wrote.

Earlier in April, a study published in the journal Nature, reported at least a 30 per cent reduction in that amount of ambient human noise since lockdown began in Belgium.

Washington D.C., Feb 6: An international team of astronomers has found an unusual monster galaxy that existed about 12 billion years ago when the universe was only 1.8 billion years old.

The team of astronomers was led by scientists at the University of California, Riverside.

Dubbed XMM-2599, the galaxy formed stars at a high rate and then died. Why it suddenly stopped forming stars is unclear.

"Even before the universe was 2 billion years old, XMM-2599 had already formed a mass of more than 300 billion suns, making it an ultra massive galaxy," said Benjamin Forrest, a postdoctoral researcher in the UC Riverside Department of Physics and Astronomy and the study's lead author.

"More remarkably, we show that XMM-2599 formed most of its stars in a huge frenzy when the universe was less than 1 billion years old and then became inactive by the time the universe was only 1.8 billion years old," Forrest added.

The team used spectroscopic observations from the W. M. Keck Observatory's powerful Multi-Object Spectrograph for Infrared Exploration or MOSFIRE, to make detailed measurements of XMM-2599 and precisely quantify its distance.

The study results appear in the Astrophysical Journal.

"In this epoch, very few galaxies have stopped forming stars, and none are as massive as XMM-2599," said Gillian Wilson, a professor of physics and astronomy at UCR in whose lab Forrest works.

"The mere existence of ultramassive galaxies like XMM-2599 proves quite a challenge to numerical models. Even though such massive galaxies are incredibly rare at this epoch, the models do predict them."

"The predicted galaxies, however, are expected to be actively forming stars. What makes XMM-2599 so interesting, unusual, and surprising is that it is no longer forming stars, perhaps because it stopped getting fuel or its black hole began to turn on. Our results call for changes in how models turn off star formation in early galaxies," the professor stated.

The research team found XMM-2599 formed more than 1,000 solar masses a year in stars at its peak of activity -- an extremely high rate of star formation. In contrast, the Milky Way forms about one new star a year.

"XMM-2599 may be a descendant of a population of highly star-forming dusty galaxies in the very early universe that new infrared telescopes have recently discovered," said Danilo Marchesini, an associate professor of astronomy at Tufts University and a co-author on the study.

"We have caught XMM-2599 in its inactive phase," Wilson said, who led the W. M. Keck Observatory data acquisition
Co-author Michael Cooper, a professor of astronomy at UC Irvine, said this outcome is a strong possibility.

"Perhaps during the following 11.7 billion years of cosmic history, XMM-2599 will become the central member of one of the brightest and most massive clusters of galaxies in the local universe," he said.

"Alternatively, it could continue to exist in isolation. Or we could have a scenario that lies between these two outcomes," he stated.

The study was supported by grants from the National Science Foundation and NASA.

New Delhi, Jul 19: Three of the 10 most valued companies added a total of Rs 98,622.89 crore to their market valuation last week, led by stellar gains in IT major Infosys.

Seven companies from the coveted list witnessed a decline in their market valuation last week, but their cumulative loss of Rs 37,701.1 crore was less than the total gain made by three firms -- Reliance Industries Limited, Hindustan Unilever Limited and Infosys.

The market capitalisation of Infosys zoomed Rs 52,046.87 crore to Rs 3,85,027.58 crore. Shares of Infosys had rallied over 9 per cent on Thursday after the company posted a stronger-than-expected 12.4 per cent rise in the first quarter consolidated net profit.

Hindustan Unilever Limited added Rs 25,751.07 crore in its market valuation which stood at Rs 5,48,232.26 crore at close on Friday. Reliance Industries' m-cap jumped Rs 20,824.95 crore to Rs 12,11,682.08 crore.

In contrast, HDFC's valuation plunged Rs 13,920.21 crore to Rs 3,13,269.70 crore and that of Tata Consultancy Services (TCS) declined Rs 7,617.34 crore to Rs 8,26,031.21 crore.

The valuation of ICICI Bank tumbled Rs 4,205.71 crore to Rs 2,29,156.24 crore and that of Kotak Mahindra Bank by Rs 4,175.28 crore to Rs 2,62,864.37 crore.

Bharti Airtel's m-cap dipped Rs 4,009.83 crore to Rs 3,09,521.05 crore and HDFC Bank's by Rs 3,403.97 crore to Rs 6,03,463.97 crore.

The valuation of ITC declined by Rs 368.76 crore to Rs 2,38,469.29 crore.

In the ranking of top-10 firms, RIL was at the number one rank followed by TCS, HDFC Bank, HUL, Infosys, HDFC, Bharti Airtel, Kotak Mahindra Bank, ITC and ICICI Bank.

During the last week, the 30-share BSE index advanced 425.81 points or 1.16 per cent.