Tsunami hit Indian coast 1,000 yrs back: Study

October 1, 2014

New Delhi, Oct 1: Looking for data on past tsunamis for a better understanding of the natural phenomenon, a team of researchers has come upon evidence which suggests that the Indian coast was hit by a sea surge some 1,000 years back, before the tsunami of 2004 which caused massive destruction in the country.

TsunamiThe team from the Centre for Earth Sciences (CEaS) at the Indian Institute of Science (IISc) made its finding while pursuing studies in tsunami geology.

The team undertook search at different sites, including the Andaman group of islands (Hut Bay, Port Blair, Interview Island and East Island) and Kaveripattinam on the Indian east coast to collect evidence and study how the geomorphic settings of these locations make them useful archives for paleo-tsunami deposits.

Coastal strips affected by regular sea surges and by anthropogenic, or human, activities are unlikely to preserve tsunami sands whereas inland lakes and streams have a greater potential of preserving these records.

Due to their greater inland penetration, tsunami deposits tend to occupy higher elevations (>5m) as compared to storm deposits, which typically are at heights of less than 4m.

Researchers found that locally-extensive occurrence of deposits such as sand, gravel and boulders, and their typically upward and inland presence are the two important characteristics of tsunami deposits.

The research, which was published early this month in the Journal of Asian Earth Science, presents the results of studies along these coastal tracts, described as "sheltered environments", which show a higher likelihood of preserving such deposits.

The 2004 tsunami was a devastating and unprecedented experience for the Indian Ocean countries. In the absence of any known tsunami during recent or historic periods, one has to depend on geological records.

Such data is very critical towards evaluating tsunami hazards and tsunami geology is an important and fast-growing research area.

"We need to develop strategies to succeed in tsunami geology research in tropical countries with very active coastal regions that barely preserve anything beyond a few years at the most.

"Identification of potential locations is key to developing paleo-tsunami archives for tsunami hazard and recurrence studies," Gubbi Labs said quoting Kusala Rajendran, one of the authors of the paper and an Associate Professor at CEaS.

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July 9,2020

Twitter has hinted that it is planning a paid subscription platform that can be reused by other teams in the future.

The news that the micro-blogging platform is building a subscription platform with a team codenamed "Gryphon" resulted in Twitter stock rising over 8% on Wednesday.

Twitter revealed its plan via a job listing that seeks a full-stack senior software engineer in New York to join "Gryphon".

Interestingly, Twitter "edited" the job listing once the news broke, removing the part about "Gryphon" and any mention of their internal team or their subscription feature. The listing said the company is looking for an Android engineer to "work on a bevy of backend engineering teams to build components that allow for experimentation to deliver the best experience possible to all of our users".

Later, Twitter users noticed that the company restored the earlier job listing that mentioned the upcoming subscription platform and "Gryphon".

A spokesperson for Twitter told CNN on Wednesday that it's only a job posting, not a product announcement.

This is not the first time Twitter has thought of a paid product. 

In 2017, it sent out a survey to users and a preview of what a premium offering of its TweetDeck app might look like, including breaking news alerts and more analytics, according to The Verge.

"We're conducting this survey to assess the interest in a new, more enhanced version of Tweetdeck. We regularly conduct user research to gather feedback about people's Twitter experience and to better inform our product investment decisions, and we're exploring several ways to make TweetDeck even more valuable for professionals," a Twitter spokesperson had said at that time.

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June 8,2020

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.

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January 20,2020

Washington D.C., Jan 20: An American bride asked for money from her invitees so that they can be on the 'exclusive guest list'.

Weddings can be surely expensive. But is it feasible for one to charge the guests to make up for the expenses?

According to Fox News, that is exactly what happened in a recent American wedding. A 19-year-old shared on Reddit that her cousin was getting married on Sunday and announced that she would charge 50 dollars to those who wanted to attend her wedding.

"She said that they can Venmo her money so there won't be no [sic] problems and everyone who paid will be added onto the 'exclusive guest list' which basically means you won't have to wait in line while other guests pay," wrote the user named DaintySheep.

While she refused to pay for entry into her cousin's wedding the bride-to-be contacted the elders in the family which ended up in an embarrassing situation.

"She wanted to get the money she spent on her special day back. I told her I wouldn't be able to come because this was outrageous and that I wish her well on her special day. She contacted my aunt and my aunt called me cheap and rude. My parents offered to pay for my entry, but I refused," continued the disheartened girl.

While in almost every nook and cranny of the world gifting the bride-groom with money is a tradition, asking for money from friends and family to replenish the money spent on a wedding is can be said to be a rare scenario.

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