India creates history as Chandrayaan 2 lifts off

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.

Mumbai, Apr 29: Irrfan Khan, one of India's finest and most versatile actors, lost his battle with a rare form of cancer and died in a Mumbai hospital on Wednesday, a statement from his family said. He was 54

Irrfan, who was diagnosed with neuroendocrine tumour in 2018, is survived by his wife Sutapa and his sons Babil and Ayaan.

It is the second tragedy for the family in less than a week. The ?Maqbool? actor lost his mother, 95-year-old Saeeda Begum, in Jaipur just four days ago and could not attend the funeral because of the nationwide lockdown.

Irrfan, that rare actor who straddled multiple worlds, making his mark in both international and Indian cinema in roles intense and light-hearted, was admitted to the intensive care unit of the Kokilaben Dhirubhai Ambani Hospital with a colon infection

?It's saddening that this day, we have to bring forward the news of him passing away. Irrfan was a strong soul, someone who fought till the very end and always inspired everyone who came close to him. After having been struck by lightning in 2018 with the news of a rare cancer, he took life soon after as it came and he fought the many battles that came with it,? the statement from his family said

?Surrounded by his love, his family for whom he most cared about, he left for heavenly abode, leaving behind truly a legacy of his own. We all pray and hope that he is at peace. And to resonate and part with his words he had said, 'As if I was tasting life for the first time, the magical side of it',? it added.

The news of his death was first confirmed by his "Piku" director Shoojit Sircar who sent his condolences to the family and doffed his hat to the actor's fighting spirit

"My dear friend Irfaan. You fought and fought and fought. I will always be proud of you.. we shall meet again.. condolences to Sutapa and Babil.. you too fought, Sutapa you gave everything possible in this fight. Peace and Om shanti. Irfaan Khan salute," the director said on Twitter.

Irrfan's death came the morning after news that he had been admitted to the ICU with a colon infection.

The self-effacing National Award winner, who acted in films as diverse as ?Life of Pi?, ?The Namesake? and ?Haasil?, had stayed away from the public eye after his diagnosis in 2018 when he went to the UK for treatment.

He returned home in 2019 and shot for "Angrezi Medium", the sequel to his 2017 hit "Hindi Medium". However, his health condition prevented him from promoting the movie, which hit the theatres in March just before the lockdown that began on March 25.

New Delhi, Jun 11: Petrol and diesel prices on Thursday were hiked by 60 paise per litre each - the fifth straight daily increase in rates since oil PSUs ended an 82-day hiatus in rate revision.

Petrol price in Delhi was hiked to Rs 74 per litre from Rs 73.40 while diesel rates were increased to Rs 72.22 a litre from Rs 71.62, according to a price notification of state oil marketing companies.

Rates have been increased across the country and vary from state to state depending on the incidence of local sales tax or VAT.

This is the fifth daily increase in rates in a row since oil companies on Sunday restarted revising prices in line with costs, after ending an 82-day hiatus.

In five hikes, petrol price has gone up by Rs 2.74 per litre and diesel by Rs 2.83.