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Washington DC, Jun 8: Astronomers acting on a hunch have likely resolved a mystery about young, still-forming stars and regions rich in organic molecules closely surrounding some of them.

They used the National Science Foundation's Karl G Jansky Very Large Array (VLA) to reveal one such region that previously had eluded detection and that revelation answered a longstanding question.

The regions around the young protostars contain complex organic molecules which can further combine into prebiotic molecules that are the first steps on the road to life.

The regions, dubbed "hot corinos" by astronomers, are typically about the size of our solar system and are much warmer than their surroundings, though still quite cold by terrestrial standards.

The first hot corino was discovered in 2003 and only about a dozen have been found so far. Most of these are in binary systems, with two protostars forming simultaneously.

Astronomers have been puzzled by the fact that, in some of these binary systems, they found evidence for a hot corino around one of the protostars but not the other.

"Since the two stars are forming from the same molecular cloud and at the same time, it seemed strange that one would be surrounded by a dense region of complex organic molecules and the other wouldn't," said Cecilia Ceccarelli, of the Institute for Planetary Sciences and Astrophysics at the University of Grenoble (IPAG) in France.

The complex organic molecules were found by detecting specific radio frequencies, called spectral lines, emitted by the molecules. Those characteristic radio frequencies serve as "fingerprints" to identify the chemicals.

The astronomers noted that all the chemicals found in hot corinos had been found by detecting these "fingerprints" at radio frequencies corresponding to wavelengths of only a few millimetres.

"We know that dust blocks those wavelengths, so we decided to look for evidence of these chemicals at longer wavelengths that can easily pass through dust," said Claire Chandler of the National Radio Astronomy Observatory, and principal investigator on the project.

"It struck us that dust might be what was preventing us from detecting the molecules in one of the twin protostars," added Chandler.

The astronomers used the VLA to observe a pair of protostars called IRAS 4A, in a star-forming region about 1,000 light-years from Earth. They observed the pair at wavelengths of centimetres.

At those wavelengths, they sought radio emissions from methanol, CH3OH (wood alcohol, not for drinking). This was a pair in which one protostar clearly had a hot corino and the other did not, as seen using the much shorter wavelengths.

The result confirmed their hunch. "With the VLA, both protostars showed strong evidence of methanol surrounding them. This means that both protostars have hot corinos. The reason we did not see the one at shorter wavelengths was because of dust," said Marta de Simone, a graduate student at IPAG who led the data analysis for this object.

The astronomers cautioned that while both hot corinos now are known to contain methanol, there still may be some chemical differences between them. That, they said, can be settled by looking for other molecules at wavelengths not obscured by dust.

"This result tells us that using centimetre radio wavelengths is necessary to properly study hot corinos," Claudio Codella of Arcetri Astrophysical Observatory in Florence, Italy, said.

"In the future, planned new telescopes such as the next-generation VLA and SKA, will be very important to understanding these objects," added Codella.

Google on Monday announced it is gradually winding down its free public Wi-Fi Station programme currently available at over 400 railway stations in India, and will work with the Indian Railways and Railtel Corporation to help them with existing sites so they can remain useful resources for people.

Google launched its Station initiative in India in 2015 to bring fast, free public Wi-Fi to over 400 of the busiest railway stations in the country by mid-2020.

"We crossed that number by June 2018 and implemented Station in thousands of other locations around the country in partnership with telecommunications companies, ISPs and local authorities," Caesar Sengupta, Vice President, Payments and Next Billion Users, Google, said in a statement.

"Over time, partners in other countries asked for Station too and we responded accordingly. We're grateful for these partnerships, especially with the Indian Railways and the Government of India, that helped us serve millions of users over the last few years," he added.

According to Google, the decision to shut Station has been taken keeping the affordable mobile data plans and mobile connectivity in mind that is improving globally including in India.

"India, specifically now has among the cheapest mobile data per GB in the world, with mobile data prices having reduced by 95 per cent in the last 5 years, as per TRAI in 2019," said Sengupta.

The Indian users consume close to 10GB of data, each month, on average, according to reports.

"Our commitment to supporting the next billion users remains stronger than ever, from continuing our efforts to make the internet work for more people and building more relevant and helpful apps and services," Sengupta noted.

Global networking giant Cisco last year teamed up with Google to roll out free, high-speed public Wi-Fi access globally, starting with India.

The first pilot under the partnership was rolled out at 35 locations in Bengaluru.

Sengupta said that in addition to the changed context, the challenge of varying technical requirements and infrastructure among our partners across countries has also made it difficult for Station to scale and be sustainable, especially for our partners.

"And when we evaluate where we can truly make an impact in the future, we see greater need and bigger opportunities in building products and features tailored to work better for the next billion user markets," he said.

Citing the current dismal aviation scenario, Air India is terminating the services of trainee cabin crew and cabin crew by withdrawing the offer of employment of those who were under training.

As per sources, the new crew and trainee pilots might reduce contracts from five years to one year. Sources said Air India is terminating 1,200 crew and employees who are more than 55-yr-old including 190 trainee pilots.

In a letter reviewed by IANS, Air India has informed an applicant who had been selected as cabin crew in August 2019 subject to successful completion of training.

"On behalf of Air India we would like to thank you for the interest shown by you in joining our organization. However, in view of the current aviation scenario, it would not be possible for Air India to impart any further training to you for engaging your services," the company said.

"In view of the above reasons, which are beyond the control of the company, it has been decided to discontinue your training arrangements and dispense with the offer of engagement with immediate effect. The bank guarantee furnished by you at the time of joining is returned herewith," Air India told the cabin crew.

"Once again on behalf of Air India we thank you for your cooperation and trust that you will appreciate the circumstances under which we are constrained to discontinue the training arrangements," the carrier said.