Astronomers discover 83 supermassive black holes 13 billion light-years away

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.

Lucknow, Jan 6: Undeterred by the large scale protests that claimed as many as 20 lives in the state, Uttar Pradesh government has started the process of implementing the controversial Citizenship (Amendment) Act.

According to sources in the government, the district magistrates have been directed to identify the migrants from Pakistan, Bangladesh and Afghanistan, who have been living in their districts.

Sources said that the state home department has given oral instructions to the district magistrates. ''No written orders have been issued,'' said a senior official here preferring anonymity.

The official said that the district magistrates would be preparing a list containing names of those minorities, who had migrated from these countries following their persecution and had been living without obtaining the citizenship of India.

According to sources, the government expected that the migrants, who could be eligible for the Indian citizenship in accordance with the CAA, could be more in number in the districts, including Rampur, Ghaziabad, Shahjahanpur, Lucknow and some others.

''The list will be sent to the union home ministry,'' the official added.

Sources said that the state government will also inform the centre about the ''illegal Muslim migrants'' for their ultimate deportation to their countries of origin.

Different parts of UP had witnessed large scale violence last month during the protests against the CAA. At least 20 people, mostly youngsters, were killed allegedly in police firing and many others were injured. The state government had denied the charge. 

Alleged police excesses during and after the protests triggered a nationwide outrage with several rights organisations and activists slamming the BJP government and demanding a high-level probe into the allegations.

The dollar's dominance will slowly melt away over the coming year on weakening global demand and a sombre U.S. economic outlook, according to a Reuters poll of currency forecasters whose views depend on there being no second coronavirus shock.

Despite fears a surge in new Covid-19 cases would delay economies reopening and stymie a tentative recovery, world stocks have rallied - with the S&P 500 finishing higher in June, marking its biggest quarterly percentage gain since the height of the technology boom in 1998.

Caught between bets in favour of riskier investments, weak U.S. economic prospects as well as an easing in the thirst for dollars after the Federal Reserve flooded markets with liquidity, the greenback fell nearly 1.0 per cent last month. It was its worst monthly performance since December.

While there was a dire prognosis from the top U.S. medical expert on the coronavirus' spread, the June 25-July 1 poll of over 70 analysts showed weak dollar projections as Fed Chair Jerome Powell on Monday reiterated the economic outlook for the world's largest economy was uncertain.

"The dollar rises in two instances: when you see risk off or when there is a situation where the U.S. is leading the global recovery, and we don't think that's going to be the case anytime soon," said Gavin Friend, senior FX strategist at NAB Group in London.

"The U.S. is playing fast and loose with the virus, and chronologically they're behind the rest of the world."

Currency speculators, who had built up trades against the dollar to the highest in two years during May, increased their out-of-favour dollar bets further last week, the latest positioning data showed.

About 80 per cent of analysts, 53 of 66, said the likely path for the dollar over the next six months was to trade around current levels, alternating between slight gains and losses in a range. That suggests the greenback may be at a crucial crossroad as more currency strategists have turned bearish.

But more than 90 per cent, or 63 of 68, said a second shock from the pandemic would push the dollar higher. Five said it would push the U.S. currency lower.

Much will also depend on debt servicing and repayments by Asian, European and other international borrowers in U.S. dollars.

While an early shortage of dollars in March from the pandemic's first shock pushed the Fed to open currency swap lines with major central banks, international funding strains have eased significantly since. In recent weeks, usage of the facility has reduced dramatically.

That trend is expected to continue over the next six months with major central banks' usage of swap lines to "stay around current levels", according to 32 of 46 analysts. While 13 predicted a sharp drop, only one respondent said use of them would "rise sharply".

The dollar index, which measures the greenback's strength against six other major currencies, has slipped over 5 per cent since touching a more than three-year high in March.

When asked which currencies would perform better against the dollar by end-December, a touch over half of 49 respondents said major developed market ones, with the remaining almost split between commodity-linked and emerging market currencies.

"The dollar is so overvalued, and has been overvalued for a long time, it's time now for it to come back down again, as we head towards the (U.S.) election," added NAB's Friend.

Over the last quarter, the euro has staged a 1.8 per cent comeback after falling by a similar margin during the first three months of the year. For the month of June, the euro was up 1.2 per cent against the dollar.

The single currency was now expected to gain about 2.5 per cent to trade at $1.15 in a year from around $1.12 on Wednesday, slightly stronger than $1.14 predicted last month. While those findings are similar to what analysts have been predicting for nearly two years, there was a clear shift in their outlook for the euro, with the range of forecasts showing higher highs and higher lows from last month.

"In comparison to even a month or two ago, the outlook in Europe has improved significantly," said Lee Hardman, currency strategist at MUFG.

"I think that makes the euro look relatively more attractive and cheap against the likes of the dollar. We're not arguing strongly for the euro to surge higher, we're just saying, after the weakness we have seen in recent years, there is the potential for that weakness to start to reverse."