Urjaa Guru Arihant Rishi demands total ban on liquor during LS polls

Leiden, Jul 2: Astronomers have discovered a luminous galaxy caught in the act of reionizing its surrounding gas only 800 million years after the Big Bang.

The research, led by Romain Meyer, PhD student at UCL in London, UK, has been presented at the virtual annual meeting of the European Astronomical Society (EAS).

Studying the first galaxies that formed 13 billion years ago is essential to understanding our cosmic origins. One of the current hot topics in extragalactic astronomy is 'cosmic reionization,' the process in which the intergalactic gas was ionized (atoms stripped of their electrons).

Cosmic reionization is similar to an unsolved murder: We have clear evidence for it, but who did it, how and when? We now have strong evidence that hydrogen reionization was completed about 13 billion years ago, in the first billion years of the universe, with bubbles of ionized gas slowly growing and overlapping.

The objects capable of creating such ionized hydrogen bubbles have however remained mysterious until now: the discovery of a luminous galaxy in which 60-100 percent of ionizing photons escape, is likely responsible for ionizing its local bubble. This suggests the case is closer to being solved.

The two main suspects for cosmic reionization are usually 1) a population of numerous faint galaxies leaking ~10 percent of their energetic photons, and 2) an 'oligarchy' of luminous galaxies with a much larger percentage (>50 percent) of photons escaping each galaxy.

In either case, these first galaxies were very different from those today: galaxies in the local universe are very inefficient leakers, with only <2-3 percent of ionizing photons escaping their host. To understand which galaxies governed cosmic reionization, astronomers must measure the so-called escape fractions of galaxies in the reionization era.

The detection of light from excited hydrogen atoms (the so-called Lyman-alpha line) can be used to infer the fraction of escaping photons. On the one hand, such detections are rare because reionization-era galaxies are surrounded by neutral gas which absorbs that signature hydrogen emission.

On the other hand, if this hydrogen signal is detected it represents a 'smoking gun' for a large ionized bubble, meaning we have caught a galaxy reionizing its surroundings. The size of the bubble and the galaxy's luminosity determines whether it is solely responsible for creating this ionized bubble or if unseen accomplices are necessary.

The discovery of a luminous galaxy 800 million years after the Big Bang supports the scenario where an 'oligarchy' of bright leakers emits most of the ionizing photons.

"It is the first time we can point to an object responsible for creating an ionized bubble, without the need for a contribution from unseen galaxies.

Additional observations with the upcoming James Webb Space Telescope will enable us to study further what is likely one of the best suspects for the unsolved case of cosmic reionization," said Meyer.

New Delhi, Jun 7: The Government of India (GoI) must strengthen the laws to protect animals, said People for the Ethical Treatment of Animals (PETA) India CEO Dr Manilal Valliyate on Sunday, following an elephant's death in Kerala and cow injured due to ingestion of explosives in Himachal Pradesh.

"Such incidents are not just restricted to certain regions but are happening all across the country. PETA receives more than 100 similar cases every day. People send in their complaints to us, not just for cows and elephants but for so many other animals as well," he said.

The PETA chief urged the GoI to strengthen the laws established to protect animals.

"As per the current laws set out against animal cruelty, the perpetrator would only be charged Rs 50,000 as a fine. That is equivalent to no punishment at all," added PETA India CEO.

He expressed his anguish against municipal agencies as well, saying that they are not doing "serious" work. He also highlighted how cows are left on the roads to wander, after milking them, to feed on garbage, in several parts of the country.

"These injustices against animals through explosives has been going on for quite a while. But for the first time, it has received such public attention," he said.

After a pregnant elephant was fed cracker-filled pineapple and her eventual death on May 27 in Kerala's Palakkad district, a pregnant cow sustained fatal injuries on May 25 due to accidental ingestion of explosives in Dadh village of Bilaspur district of Himachal Pradesh.

One person has been arrested in the Dadh village for allegedly hurting the cow.

New Delhi, Mar 14: Excise duty on petrol and diesel was on Saturday hiked by ₹3 per litre as the government looked to mop up gains arising from fall in international oil prices.

Special excise duty on petrol was hiked by ₹2 to ₹8 per litre incase of petrol and to Rs 4 incase of diesel, an official notification said.

Additionally, road cess on petrol was raised by ₹1 per litre each on petrol and diesel to ₹10.

The increase in excise duty would in normal course result in a hike in petrol and diesel prices but most of it would be adjusted against the fall in rates that would have necessitated because of slump in international oil prices.