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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.

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.

Kochi, May 22: During the nationwide COVID-19 lockdown, Kerala recorded the highest number of cyber attacks followed by Punjab and Tamil Nadu, a study by anti-virus software firm K7 Computing said on Thursday.

In a statement issued in Chennai, the company said its K7 Computing's Cyber Threat Report, a comprehensive analysis of cyber attacks during the lockdown has found that Kerala recorded the highest number of cyber attacks during this period. The report analyses various cyber attacks within India during the pandemic and reveals that threat actors targeted the state with COVID-themed attacks aimed at exploiting user trust.

In Kerala, regions like Kottayam, Kannur, Kollam, and Kochi saw the highest hits with 462, 374, 236, and 147 attacks respectively, while the state as a whole saw around 2,000 attacks during the period - the highest thus far in the country.

This was followed by Punjab with 207 attacks and Tamil Nadu with 184 attacks, the company said.

The sudden surge in the frequency of attacks witnessed from February 2020 to mid-April 2020 indicates that scamsters across the world were exploiting the widespread panic around coronavirus at both the individual and corporate level.

These attacks aimed to compromise computers and mobile devices to gain access to users' confidential data, banking details, and cryptocurrency accounts.

The key threats seen during this period ranged from phishing attacks to rogue apps disguised as COVID-19 information apps that targeted users' sensitive data. Phishing attacks were noticed more in Tier-II and Tier-III cities while the metros fared better. Smaller cities saw over 250 attacks being blocked per 10,000 users.

Users from Ghaziabad and Lucknow seem to have faced almost 6 and 4 times the number of attacks as Bengaluru users.

According to the statement, a majority of the recorded attacks were phishing attacks with sophisticated campaigns that could easily snare even the most educated users. These attacks were aimed at heightening users' fears and creating a sense of urgency to take action.

K7 Labs noticed phishing attacks where scamsters posed as representatives of the United States Department of Treasury, the World Health Organization (WHO), and the Centres for Disease Control and Prevention (CDC), the company said.

Users were encouraged to visit links that would automatically download malware on the host computer such as the Agent Tesla keylogger or Lokibot information-stealing malware, infamous banking Trojans such as Trickbot or Zeus Sphinx, and even disastrous ransomware.

Other attacks included infected COVID-19 Android apps like CoronaSafetyMask that scam users with promises of masks for an upfront payment; the spyware app Project Spy; and seemingly genuine apps that are infected with dangerous malware like banking Trojans such as Ginp, Anubis and Cerberus.

"Covid-19 has created an ideal situation for various threat actors to target individuals and enterprises alike. The panic caused by the stringent lockdown measures and rapid spread of this virus has left many people looking for more information on the situation," J. Kesavardhanan, Founder and CEO of K7 Computing was quoted as saying in the statement.

"Threat actors exploit this fear to their advantage and scam users into downloading malicious software and divulging sensitive information like banking codes. The need to be cyber cautious has never been greater. This is more so in the case of corporates who have adopted a work from home policy hurriedly without adequate cyber hygiene. We have seen an increase in attacks on enterprises and SME employees as well," he added.

Such attacks are expected to continue till normalcy returns. Social engineering attacks targeted at winning users' trust will gain momentum.

Healthcare institutions, well-known government offices, and international organisations will continue to be a prime target throughout the pandemic, the statement said.