Why Pluto, now a dwarf planet, remains a complex mystery

 Until the year 2006, every school science book harped upon there being nine planets and thereafter the count got revised to eight! After 76 years since its discovery in 1930, during the International Astronomical Union meeting held in Paris, the scientist fraternity astounded the world by declaring Pluto, the ninth and the smallest planet of the solar system no longer considered as a planet, generating mass confusion about its identity!

Pluto, named after the Roman God of death, is a cold, frigid world with an average surface temperature of about -235 degrees Celsius. It takes 5.5 hours for the sunlight to reach this celestial body and it completes one revolution around the sun in 248 Earth years; one day on Pluto is equivalent to 6.5 Earth days. A person on Pluto would weigh 1/15 of what they weigh on Earth. Its largest moon Charon is nearly half its size. However, they are much similar in mass which causes Pluto to wobble as it travels through space, an un-planet-like behaviour. This along with the discovery of similar-sized but more massive Eris and many other comparable celestial objects near Pluto prepared the grounds for it to be booted out from the elite group of planets and into a brand-new category of celestial objects called ‘dwarf planets’.

The word “planet” has been redefined over the years since it was first coined centuries ago by ancient Greeks. Any object that appeared to wander through the skies was termed a planet. In popular perception, totally based on fantasy, a planet is conceptualised as a place one can visit and walk around on. Another way of instinctively defining a planet is centred on one or more of its physical features like its appreciable size, the existence of atmosphere, or perhaps the presence of satellites.

The magnificent images of Pluto that are sent back from the New Horizons probe showcase a vast array of towering exotic ice mountains, serpentine valleys and sprawling plains, dunes and volcanoes which makes Pluto look nearly Earth-like. But if these features were the deciding criteria, our moon would also qualify to be a planet, while the gas giants like Jupiter and Saturn would fail to make the cut.

Likewise, the tiny-sized Mercury with no moons and a faint atmosphere is a planet while Ganymede, the largest satellite within the solar system or Titan, the largest moon of Saturn with a thick atmosphere of Pluto with five moons isn’t. Thus popular acuities are not scientific practices of defining what a planet is.

The definition of a planet isn’t arbitrary. A new, subtle and nuanced approach to what constitutes a planet was formulated in 2006.

A heavenly body is designated as a planet if it meets three essential criteria – the object should revolve around the sun, it should be spherical in shape and the area around its orbit should not have any equivalent or bigger cosmic object. In other words, owing to its gravity the planet should clear asteroids or any other celestial objects out of its way.

While Pluto fulfils the first two benchmarks, it falters on the third and was subsequently demoted to the position of a dwarf planet which currently is a group of five entities, Pluto being the largest.

Elimination of Pluto from the exclusive planet club has proved to be one of the most divisive issues in modern science. But removing the controversial third condition as a prerequisite would reclassify not only Pluto, but also our moon, many moons of Jupiter and Saturn, Ceres and some more asteroids as planets, taking the total tally of planets in our solar system to more than 100. So it seems that the status of Pluto as a dwarf planet is unlikely to change in times to come.

Pluto may have lost its tag as a planet, but it continues to be a noteworthy and mysterious place with unparalleled complexity, the king of the Kuiper belt, with potency to help us gain insights into the ultimate frontier of our solar system and thus help apprehend the secrets of its birth.

Source: Indian Express, 31/03/22

What if there was no carbon dioxide in the air?

 

As a life force behind photosynthesis, lack of this gas would create a domino effect with the food chain - no living plants and animals would mean no living humans.

Carbon dioxide stands out as one of the few entities which, although invisible, regularly feature in daily headlines, lead stories and public conversations for the wrong reasons, bearing the brunt of rising global temperatures and sea levels and melting glaciers. However, carbon dioxide (CO2), a naturally occurring tasteless, odorless gas in our atmosphere is equally vital to life as oxygen.

The natural world works on an incredibly delicate balance maintaining an equilibrium in the CO2 produced and consumed. The CO2 levels have witnessed stupendous rise since the industrial revolution with mother earth bearing the detrimental impact of climate change or global warming thereby bringing disrepute and infamously lending it a rogue name. Though it may seem that the absence of this greenhouse gas will end all our climate change woes creating cleaner earth, the outcome would be catastrophic, making it a frigid, dead planet.

As a life force behind photosynthesis, lack of this gas would create a domino effect with the food chain – no living plants and animals would mean no living humans. The problem is not CO2, but the excess of it.

The usages of CO2 are varied across all forms including solid form called dry ice. Being inert, inflammable, inexpensive and easy to mass produce, it finds applications across diverse industries including food and medical industry and even in the entertainment industry to name a few.

As a lifesaving gas, when compressed to a liquid, it is widely used as a fire extinguishing medium. When released, the liquid CO2 reverts to gas form due to pressure and temperature drop, consequently extinguishing the fire. The wide usage for welding purposes, inflating rafts and life jackets further adds to its versatility in industrial applications.

The use of CO2 in the food industry is not limited to putting fizz in the soft drinks, making our cakes and bread soft and spongy, it can be used to make decaf coffee too! In fact, it has become an indispensable tool in commercial kitchens and restaurants. Dry food like grains if kept in a CO2 environment does not spoil for a very long time. Dry ice has made transportation and storage of frozen food stress-free. With a surface temperature as low as -78.5o C, it keeps food fresh. Finding an easy usage in portable coolers without requiring any external power source, it is proving to be a boon for economical transportation of perishable food items.

As dry ice directly evaporates, without coming into the liquid state, it is being rampantly used in medical research and investigations, storing biological samples, medical supplies and even organs without the fear of any kind of contamination. Applications in dermatological treatments for removal of acne, improving the texture and polishing the skin has made it a beauty buzzword.

CO2 plays an enviable role in the oil and gas industry too. When injected into oil reservoirs, it dissolves in crude oil thereby reducing its viscosity and enabling the oil to be extracted easily while remaining underground. This has also prompted the industry wide initiatives to capture and store CO2 into underground formations viz. depleted and abandoned oil fields, or rocks beneath the sea. Once placed there, CO2 remains trapped indefinitely and consequently removing the extra CO2 from the atmosphere. This potential benefit is attracting huge investment and further research towards scaling up and becoming a safe, viable commercial proposition.

This gas has found vivid applications to create suspense or melodrama, making it a scenic choice of the multibillion dollar entertainment industry. It is used in creating a dramatic and versatile effect of fog/ haze effect in movies and TV serials across genres, be it horror or sci-fi.

Its usage in rendering animals and birds unconscious before being slaughtered also makes it a ubiquitous choice among butchers.

Efforts are currently underway to produce clean, carbon-neutral fuel with the help of CO2. This so-called process of Carbon Engineering involves pulling out CO2 from the atmosphere, combining it with hydrogen and producing a synthetic fuel option. This is metaphorically having your cake and eating it too!

Is CO2 a necessary evil, a boon or a bane? CO2 is not exactly the villain, rogue or the monster gas as it is made out to be. It is rather a boon like water; too little will make us thirsty, too much will cause floods putting life on earth in jeopardy. In fact, the discourse around CO2 and global warming is yet another reminder to mankind to live within our resources and in balance with nature.

By Rachna Arora

Source: Indian Express, 4/02/22

How do birds make their nests?

 

Birds are really intelligent animals. They use their intelligence, along with their beaks and feet, to find the most clever ways to make nests with whatever materials are available.

The first thing to know is not all birds make nests. For example, emperor penguin fathers carry their precious egg on their feet (to keep it off the frozen ground). Some birds, such as cuckoos, will lay their eggs in someone else’s nests. Others lay them on the ground among leaves or pebbles, or on cliffs with very little protection.

For the birds that do build nests, there is one main goal: to keep their eggs and chicks safe. Many birds also make their nests in tree hollows, including parrots. That’s just one reason it’s important to not cut trees down!

Meanwhile, kookaburras use their powerful beaks to burrow into termite nests and make a cosy nest inside. And the cute spotted pardelote will dig little burrows in the side of earth banks — with a safe and cosy spot for its eggs at the end of the tunnel.

Some birds, such as brush turkeys, spend months building huge mounds on the ground which can heat up from the inside. The male turkey makes sure the ground is exactly the right temperature inside the mound, and then lets the female lay the eggs inside. He’ll take big mouthfuls of dirt surrounding the eggs to check it’s not too hot or cold.

Birds construct many different types of nests. There are floating nests, cups, domes, pendulums and basket-shaped nests. They can be made out of sticks, twigs, leaves, grasses, mosses or even mud.

Magpie-larks (also called ‘peewees’), apostlebirds and choughs make mud bowl nests that look like terracotta plant pots. To do this, they gather mud and grasses in their beaks and shake it around to mix it with their saliva. They can then attach it to a branch and build upwards until the nest is complete. In fact, bird saliva is a really strong and sticky material to build nests with.

Birds will often mix saliva and mud to make a type of glue. And some swiftlets make their nests entirely out of solidified saliva. People will even eat these nests in bird’s nest soup!

Willie wagtails use another type of glue – sticky spiderwebs. They sew grasses together using spider webs and the webs help keep the nests strong against wind and water, too. They have to perfect the technique of gathering the spiderweb though, otherwise it can get tangled in their feathers.

Magpies and crows, both common visitors to our gardens, are also clever nest builders. Not only can they expertly layer their sticks into a bowl, but they also use many human-made materials in their nests. You might find them using fabric, string or a wire to hold a nest together. Some birds such as red kites have even been seen decorating their nests with human rubbish.

And Australian babblers line the inside of their nests with a thick wall of kangaroo poo, followed by soft fluff, to keep their chicks warm. To actually weave the nests, birds will usually create a base by layering sticks or twigs in the place they want it. Then they use their beaks and feet to weave a chosen materials through, to hold the sticks in place. They can pull strips of material with their beaks over and under, just like weaving a rug. They can even tie knots!

Nests can take a really long time to make, so they’re often reused year after year. Weaver birds are so good at weaving, they can build complex nests that cover entire trees and have several chambers. To summarise, birds are really intelligent animals. They use their intelligence, along with their beaks and feet, to find the most clever ways to make nests with whatever materials are available. And they get better at this by learning from others, such as their parents or peers.

Written by Kiara L’Herpiniere

Source: Indian Express, 26/11/21

How much do baleen whales eat in a day?

 

The new study has observed that baleen whales can consume as much as 16 tonnes of food per day, which constitutes as much as 30% of their total body mass.

A recently published study in Nature has established that baleen whales, the largest animals on the planet, eat thrice or even more the amount of food than previously thought.

The study, conducted primarily in the Southern Ocean, monitored multiple individuals from seven baleen whale species – humpback, fin, blue, minke, right and bowhead and the Bryde’s whale – as they went about their daily business.Baleen whales are so named because they have bristles (baleens) inside their mouth in which their prey (krill) gets stuck. Their close relatives, from the order Cetacea, are toothed whales that have teeth instead of bristles.

Whales were tagged with sensors that tracked their movements, and acoustics were used to identify places where their prey was concentrated.

The methods used are notable as it is the first time that whale movement and diet could be empirically monitored. Earlier studies employed examining the contents of the stomach of killed whales or by employing mathematical models based on metabolic rates of baleen whales. Both these methods suffered veritable disadvantages.

Direct measurements of stomach contents were often done during specific times of the year, which, however, gave a “biased” picture. Some even tried to fill the stomach up with water or gas, but the elasticity of the stomach membrane decreases significantly upon death. As for mathematical models, the metabolism rates involved were often ‘assumed,’ or taken from some captured toothed whales or dolphins.

The new study has observed that baleen whales can consume as much as 16 tonnes of food per day, which constitutes as much as 30% of their total body mass.

Prior studies, researchers maintain, have grossly underestimated the gargantuan appetites of the largest aquatic mammals, wherein “even their highest assumptions…underestimates reality”.

Generalist whales like fin and humpback, as opposed to specialist ones (the blue, right and bowhead whales), may be better buffered against the effects of climate change on marine life, the authors argue.

Different feeding strategies

The researchers highlight differences in the feeding strategies of these species as well. The right and bowhead whales prey on crustaceans by moving through a swarm of crustaceans with an open mouth, a strategy called ‘ram’ or ‘continuous’ feeding.

Another strategy, called ‘lunge’ feeding, involves discrete jumps (lunges) at prey colonies. Lunge feeding is exhibited by the blue, fin and humpback whales. A single whale adopting a lunge strategy can filter up to 17000 cubic metres of water a day, while a ram feeding tends to process four times as much.

Whales and iron cycle

These findings are particularly important as whales are apex predators in food chains they operate and therefore render important ecosystem services and functions.

The foremost among these is the marine iron cycle. Most iron in the ocean exists in biomass. One of the largest reservoirs of iron in the ocean is krill. Krill populations constitute nearly 24% of the total iron in surface waters, an earlier study has established. Upon devouring krill, whales defecate iron-rich faeces. These are then eaten by the planktonic community, which are then, in turn, eaten by krill. And the cycle goes on.

A 2010 study estimated that the amount of iron in whale faeces can be “ten million times that of Antarctic seawater”, while the present study asserts that whales could recycle 7000 to 15000 tonnes of iron each year.

The authors also highlight how whales play the role of ecosystem engineers by mixing iron in the water by virtue of their sheer movement.

This also explains the ‘krill paradox’ whereby it was observed that krill populations actually declined during the whaling years (1910-70), whereas the prey population usually explodes in the absence of a predator.

Even the numbers of competing predator species, which were expected to increase with whaling, have either declined or remained the same (essentially because their food source, krill, was declining).
“Encouraging cetacean populations to recover may restore ecosystem function lost in the 20th century and lead to enhanced oceanic productivity,” authors hope, even as they acknowledge that twentieth-century whaling reduced baleen whales populations by more than two-thirds.

Written by Ritvik Chaturvedi 

Source: Indian Express, 12/11/21

Jharkhand’s Singhbhum region may have been earliest continental land to rise above ocean, reveals study

 

Scientists from India, Australia and the US have found that the Earth’s first continents emerged from the ocean 700 million years earlier than thought.

Researchers have always been intrigued about when the landmasses we reside on came into existence and till recently, it was widely accepted that continents rose out of the ocean about 2.5 billion years ago. However, a recent study has changed that notion.

A recent research has shown that the Earth’s first continents may have risen out of the ocean about 700 million years earlier than previously thought. And to the surprise of many, the earliest continental land to have risen about 3.2 billion years ago may have been Jharkhand’s Singhbhum region. Scientists from India, Australia and the US have found sandstones in Singhbhum with geological signatures of ancient river channels, tidal plains and beaches over 3.2 billion years old, representing the earliest crust exposed to air.

When asked as to how Singhbhum came into the picture of research related to Earth Sciences, Dr Priyadarshi Chowdhury of Monash University, the study’s lead author, told indianexpress.com that the answer to “when the first landmasses were formed lay in the sedimentary rocks of the region”.

“We found a particular type of sedimentary rocks, called sandstones. We then tried to find their age and in which conditions they have formed. We found the age by analysing the uranium and lead contents of tiny minerals. These rocks are 3.1 billion years old, and were formed in ancient rivers, beaches, and shallow seas. All these water bodies could have only existed if there was continental land. Thus, we inferred that the Singhbhum region was above the ocean before 3.1 billion years ago,” Chowdhury said.

But, Chowdhury said, patches of the earliest continental land also exist in Australia and South Africa.

Speaking about how they determined that the region rose above ocean during the timeframe mentioned above, Chowdhury explained: “We studied the granites that form the continental crust of the Singhbhum region. These granites are 3.5 to 3.1 billion years old and formed through extensive volcanism that happened about 35-45 km deep inside the Earth and continued on-and-off for hundreds of millions of years until all the magma solidified to form a thick continental crust in the area. Due to the thickness and less density, the continental crust emerged above surrounding oceanic crust owing to buoyancy.”

“This is the most direct, unambiguous date yet for the emergence of continental land,” Chowdhury said. The findings have appeared in the Proceedings of the National Academy of Sciences, a US research journal.

The research also tends to break another well-accepted notion: continents rose above the ocean due to plate tectonics, which is the major driver today for increases in the elevation of land masses.

“We have plate tectonics today to control the elevation. When two continents’ (plates) collide, you form the Himalayas, you form the Alps,” he said. “That wasn’t the case 3 billion years [ago]. The first continents probably rose above sea level as they were inflated by progressive injection of magma derived from deep in the Earth.”

The researchers believe that the earliest emergence of continents would have contributed to the proliferation of photosynthetic organisms, which would have increased oxygen levels in the atmosphere. “Once you create land, what you also create is shallow seas, like lagoons,” Chowdhury added, accelerating the growth of oxygen-producing life forms that may have boosted oxygen in the atmosphere and ocean.

Exhorting on the importance of such studies, Chowdhury said that at a time when the entire world was debating about changes in climate, it is very important to understand how our atmosphere, oceans and climate came into existence and how they interacted with geological processes operating deep inside Earth to make our planet habitable.

“It allows us to link the interior of Earth to its exterior in deep time. India has three other ancient continental fragments — Dharwar, Bastar and Bundelkhand regions. We need to understand their evolution. What we did in Singhbhum may serve as a template for studying these other cratons,” he added.

Written by Rounak Bagchi

Source: Indian Express, 11/11/21

Goodbye, Columbus: Vikings crossed the Atlantic 1,000 years ago

 Long before Columbus crossed the Atlantic, eight timber-framed buildings covered in sod stood on a terrace above a peat bog and stream at the northern tip of Canada’s island of Newfoundland, evidence that the Vikings had reached the New World first.

But precisely when the Vikings journeyed to establish the L’Anse aux Meadows settlement had remained unclear – until now.

Scientists on Wednesday said a new type of dating technique using a long-ago solar storm as a reference point revealed that the settlement was occupied in 1021 AD, exactly a millennium ago and 471 years before the first voyage of Columbus. The technique was used on three pieces of wood cut for the settlement, all pointing to the same year.

The Viking voyage represents multiple milestones for humankind. The settlement offers the earliest-known evidence of a transatlantic crossing. It also marks the place where the globe was finally encircled by humans, who thousands of years earlier had trekked into North America over a land bridge that once connected Siberia to Alaska.

“Much kudos should go to these northern Europeans for being the first human society to traverse the Atlantic,” said geoscientist Michael Dee of the University of Groningen in the Netherlands, who led the study published in the journal Nature.

The Vikings, or Norse people, were seafarers with Scandinavian homelands: Norway, Sweden and Denmark. They ventured through Europe, sometimes colonizing and other times trading or raiding. They possessed extraordinary boat-building and navigation skills and established settlements on Iceland and Greenland.

“I think it is fair to describe the trip as both a voyage of discovery and a search for new sources of raw materials,” Dee said. “Many archaeologists believe the principal motivation for them seeking out these new territories was to uncover new sources of timber, in particular. It is generally believed they left from Greenland, where wood suitable for construction is extremely rare.”

Their wooden vessels, called longboats, were propelled by sail and oars. One surviving example, called the Oseberg ship, is roughly 70 feet.

The Viking Age is traditionally defined as 793-1066 AD, presenting a wide range for the timing of the transatlantic crossing. Ordinary radiocarbon dating – determining the age of organic materials by measuring their content of a particular radioactive isotope of carbon – proved too imprecise to date L’Anse aux Meadows, which was discovered in 1960, although there was a general belief it was the 11th century.

The new dating method relies on the fact that solar storms produce a distinctive radiocarbon signal in a tree’s annual growth rings. It was known there was a significant solar storm -a burst of high-energy cosmic rays from the sun – in 992 AD.

In all three pieces of wood examined, from three different trees, 29 growth rings were formed after the one that bore evidence of the solar storm, meaning the wood was cut in 1021, said University of Groningen archaeologist Margot Kuitems, the study’s first author.

It was not local indigenous people who cut the wood because there is evidence of metal blades, which they did not possess, Dee said. The length of the occupation remains unclear, though it may have been a decade or less, and perhaps 100 Norse people were present at any given time, Dee said. Their structures resembled Norse buildings on Greenland and Iceland.

Oral histories called the Icelandic Sagas depict a Viking presence in the Americas. Written down centuries later, they describe a leader named Leif Erikson and a settlement called Vinland, as well as violent and peaceful interactions with the local peoples, including capturing slaves.

The 1021 date roughly corresponds to the saga accounts, Dee said, adding: “Thus it begs the question, how much of the rest of the saga adventures are true?”

Source: Indian Express, 21/10/21

Lightning may have sparked life on Earth, study finds

 

• Phosphorus is a vital building block of life as we know it, forming basic cell structures and the double helix shape of DNA and RNA.

Lightning strikes may have supplied primordial Earth with enough phosphorus to support the emergence of life, according to new research Tuesday that offered an alternative explanation as to how living organisms were born.

Phosphorus is a vital building block of life as we know it, forming basic cell structures and the double helix shape of DNA and RNA.

Billions of years ago on early Earth, most of the available phosphorus was locked away in insoluble minerals.

However one mineral, schreibersite, is highly reactive and produces phosphorus capable of forming organic molecules.

Since most schreibersite on Earth comes from meteorites, the emergence of life here has long been thought to be tied to the arrival of extraterrestrial rocks.

But schreibersite is also contained within the glass-like rock formed by lightning strikes in some types of clay-rich soils.

Researchers in the US and Britain used state of the art image techniques to analyse the amount of the phosphorus-giving mineral formed in each lightning strike.

They then estimated how much schreibersite could have been produced over the eons before and around the time of the emergence of life on Earth, around 3.5 billion years ago.

"Lightning strikes on early Earth may have provided a significant amount of reduced phosphorus," Benjamin Hess, lead study author from Yale's Department of Earth and Planetary Sciences, told AFP.

"And by synthesising the best of our knowledge of the conditions of early Earth, I think our results bear out this hypothesis."

Writing in the journal Nature Communications, Hess and his colleagues estimated that lightning strikes could have produced between 110 and 11,000 kilogrammes of phosphorus a year.

Using simulations of the climate on early Earth, they said that while meteor strikes began to decline after the Moon was formed 4.5 billion years ago, lightning strikes surpassed space rocks for phosphorus production around 3.5 billion years ago.

That timing coincides with the origin of life.

Hess said that the research didn't entirely discount meteorites as another source of life-giving phosphorus.

"Meteor impacts around the time of the emergence of life are far less than thought a decade ago," he said.

"But I don't see our work as a competition against meteorites as a source of phosphorus. The more sources, the better."

He said that he wanted to find out whether lightning strikes produce trace amounts of phosphorous on other planets where meteor strikes are rare.

"Meteor impacts decrease through time whereas lightning, at least on Earth, is relatively constant through time," Hess added.

Source: Hindustan Times, 16/03/21

World’s richest men, Elon Musk and Jeff Bezos, fight over satellite fleets

 The world’s two richest men are duking it out before U.S. regulators over celestial real estate for their satellite fleets.

Elon Musk’s SpaceX has asked the Federal Communications Commission for permission to operate Starlink communications satellites at a lower orbit than first planned.

Jeff Bezos’s Amazon.com Inc. says the move would risk interference and collisions with its planned Kuiper satellites, which like Starlink are designed to beam internet service from space.

A dispute that would normally be confined to regulatory filings is spilling into public view, in a spat that showcases the large personalities involved as billionaires chase dreams in the sky.

“It is SpaceX’s proposed changes that would hamstring competition among satellite systems,” Amazon tweeted Tuesday from its official news account. “It is clearly in SpaceX’s interest to smother competition in the cradle if they can, but it is certainly not in the public’s interest.”

The statement followed a tweet from Musk, the richest person according to data compiled by Bloomberg.

“It does not serve the public to hamstring Starlink today for an Amazon satellite system that is at best several years away from operation,” Musk said in a tweeted reply to coverage by CNBC journalist Michael Sheetz.

Musk’s Space Exploration Technologies Corp. has launched more than 1,000 satellites for its Starlink internet service and is signing up early customers in the U.S., U.K. and Canada. Amazon last year won FCC permission for a fleet of 3,236 satellites and has yet to launch any.

Amazon earlier urged the FCC to reject SpaceX’s request for lower orbits. It said the change would put SpaceX satellites in the midst of the Kuiper System orbits, according to filings at the agency.

SpaceX pushed back in calls to the FCC, saying its plans wouldn’t increase interference for what it termed Amazon’s “still nascent plans.”

A lower orbit allows quicker internet service because the signal doesn’t travel as far. SpaceX told the FCC that having the satellites closer to Earth lessens the risk of space debris because they would fall out of orbit more quickly than higher spacecraft.

SpaceX eventually plans to operate some 12,000 satellites and has won FCC authorization for about 4,400 birds, including 1,584 at 550 kilometers — where its satellites currently orbit. The company is seeking permission to stage another 2,824 satellites at the same approximate altitude, rather than twice as high as originally proposed.

Source: Indian Express, 27/01/21

India takes step closer towards mass production of hydrogen fuel from biomass: IISc Bengaluru

 

The IISc and the Research and Development Centre of Indian Oil Corporation Limited had signed a Memorandum of Understanding to develop and demonstrate biomass gasification-based hydrogen generation technology for producing fuel cell-grade hydrogen at an affordable price.

In a boost for the clean energy sector, the Indian Institute of Science (IISc), in collaboration with Indian Oil Corporation Limited, has developed a process to produce hydrogen fuel from biomass that doesn’t involve combustion.

The IISc and the Research and Development Centre of Indian Oil Corporation Limited had signed a Memorandum of Understanding to develop and demonstrate biomass gasification-based hydrogen generation technology for producing fuel cell-grade hydrogen at an affordable price.

Biomass gasification is a controlled process that involves heat, steam, and oxygen to convert biomass to hydrogen and other products without combustion. The technology developed by IISc first produces hydrogen-rich syngas (synthetic gas) from biomass and then separates hydrogen from the syngas.“The technology envisaged under this programme would not only provide a cleaner energy option for India but will also be a step towards addressing the challenge of biomass waste,” the institute mentioned in a statement.

According to the IISc, this is another step to bring hydrogen fuel into India’s mainstream energy matrix while utilising the agrarian strengths of the country.

“The developed technology will be scaled up and demonstrated at Indian Oil’s R&D Centre at Faridabad. Hydrogen generated from this demonstration plant will be used to power fuel cell buses as part of a bigger project being conceived by Indian Oil towards ushering in the country’s hydrogen economy,” an IISc spokesperson said.

Source: Indian Express, 2/11/20

Indian team studies 8,000 galaxies, says star formation could cease in two billion years

 

Taking full advantage of the uGMRT offering improved sensitivity and frequency ranges, the Indian team scanned five locations in the sky for 100 hours.

A team of Indian astronomers has calculated the amount of hydrogen gas that contributed to star formation in the universe 10 billion years ago. It has also concluded that there is just enough hydrogen gas available to support star formation for another two billion years.

Hydrogen gas in galaxies condenses to form stars. Earlier studies had shown that the rate of star formation in the universe was at its peak between eight and 10 billion years ago, a period known as the ‘epoch of galaxy assembly’, but fell sharply thereafter. To understand why, scientists from Pune-based TIFR-National Centre for Radio Astrophysics (NCRA) and Raman Research Institute (RRI), Bengaluru, used the upgraded Giant Metrewave Radio Telescope (uGMRT) in Junnar to study the rate of star formation in 8,000 galaxies based on the available hydrogen gas.

“This is for the first time we know why the rate of star formation started declining eight billion years ago. Hydrogen signal observations emerging from distant 8,000 galaxies were stacked. They reveal that the availability of hydrogen gas has shrunk dramatically, thereby slowing down the speed of star formation,” said Aditya Chowdhury, doctoral student at NCRA and the lead author of the study, published in Nature on Wednesday.

With the supply of hydrogen gas inside these galaxies now depleting, Nissim Kanekar, also the co-author of the study, remarked, “The mass of the remnant hydrogen in the galaxies suggest that star formation would not go beyond another one or two billion years from now.”

Taking full advantage of the uGMRT offering improved sensitivity and frequency ranges, the Indian team scanned five locations in the sky for 100 hours.

Unlike stars that can be detected in optical wavelengths, atomic hydrogen signals are captured only using highly sensitive radio telescopes when tuned to 21 cm wavelengths.

On uGMRT, another co-author of the study, Jayaram Chengalur, said, “Earlier, the field of view of the sky was much smaller and making such detections were not feasible.”

KS Dwarakanath from RRI explained the limitations faced during previous attempts to study hydrogen gas inside galaxies. “The narrow bandwidth of earlier GMRT allowed us to cover only 850 galaxies,” he said. It is the uGMRT which made the study of such a large number of galaxies possible, said Chengalur.

When galaxies completely run out of hydrogen gas, then the rate of star formation will further decline and eventually cease, Chowdhury said.

Source: Indian Express, 14/10/20

Solar, Lunar eclipses 2020: When and where to watch eclipses this year

We are compiling a list of all the solar and lunar eclipses of 2020 along with their timing and areas where these will be visible.

When the Sun, Earth, and the Moon align in a straight line (or form an almost straight configuration), we witness either a solar eclipse or a lunar eclipse depending on the position of the Earth. A solar eclipse happens during the New Moon when the Moon moves between Earth and the Sun to cast a shadow on the Earth blocking the rays of Sun. A lunar eclipse happens during a Full Moon when the Earth comes between the Sun and the Moon blocking the Sun’s rays from directly reaching the Moon.

Solar eclipses in 2020

There are three kinds of solar eclipses — total, partial, and annular along with rare hybrid that is a combination of an annular and a total eclipse. There are between two and five solar eclipses every year. This year, there will be two solar eclipses— one is scheduled for Jun 21 and the other one is expected to occur on December 14.

Annular solar eclipse on June 21, 2020

As per timeanddate.com, the first solar eclipse of the year 2020 will fall on June 21. It will start at 9:15 am as per Indian Standard Timing (IST) and be visible until 3:04 pm. The full eclipse will start from 10:17 am to 2:02 pm where 12:10 pm will see the maximum eclipse.

The June 21 event will be an annular solar eclipse where the Moon will cover the Sun from the centre leaving the outer rim visible, thus creating a ring of fire. The event will be visible in India as well as much of Asia, Africa, the Pacific, and the Indian Ocean. Parts of Europe and Australia will also witness the June 21 event.

Total solar eclipse on December 14, 2020

The second and last solar eclipse of the year 2020 will occur on December 14. As per timeanddate.com, the solar eclipse will start at 7:03 pm IST, reach the full eclipse by 8:02 pm, and the maximum eclipse will occur at 9:43 pm. The full eclipse will end at 11:24 pm, after which the partial eclipse will start and end by 12:23 am on December 15, 2020.

The December 14 event will be a total eclipse where the Moon completely blocks the Sun and casts a shadow over the planet. The celestial event will be visible directly from South America, Pacific, Atlantic, parts of Indian Ocean and Antarctica. Some parts of Africa will also witness the solar eclipse directly.

Lunar eclipses in 2020

Just like solar eclipses, lunar eclipses are also of three kinds– total, partial, and penumbral. The year 2020 has been listed to hold four lunar eclipses– one of which has been already witnessed in January. The remaining eclipses have been scheduled to occur in June, July, and November.

Also, just like the first lunar eclipse, the upcoming lunar eclipse of the year will be penumbral ones, which means the Moon travels through the faint penumbral portion of Earth’s shadow.

Lunar eclipse on June 5-6, 2020

As per timeanddate.com, the second lunar eclipse of the year will occur between June 5 and June 6. It will start at 11:15 pm IST on June 5 and reach the maximum eclipse at 12:54 am on June 6. The penumbral eclipse will end at 2:34 am on June 6, 2020. It will be visible in India along with much of Asia, much of Europe, Australia, Africa, South/East South America, Pacific, Atlantic, Indian Ocean, and Antarctica.

Lunar eclipse on July 5, 2020

The third lunar eclipse of the year will occur between July 5. As per timeanddate.com, it will start at 8:37 am IST, reach maximum eclipse at 9:59 am, and end at 11:22 am. As evident from the timing, it will not be visible in India. The regions which will withness the penumbral lunar eclipse of July 5 include much of Africa, much of Nort America, South/West Europe, South America, Pacific, Atlantic, Indian Ocean, and Antarctica.

Lunar Eclipse on November 30, 2020

The fourth and final lunar eclipse of the year will occur on November 30, 2020. It will start at 1:02 pm IST, and reach the maximum eclipse at 3:12 pm. The penumbral eclipse will end at 5:23 pm on November 30, 2020. This eclipse will also be not visible from India. As per timeanddate.com, the regions where it will be visible include much of Europe, much of Asia, Australia, North America, South America, Pacific, Atlantic, and the Arctic.

Notably, there will be a total of four eclipses in 2021– two will be solar eclipses and two will be lunar ones.

Source: Indian Express, 19/03/2020

Here’s what will happen when our Sun dies

A new study reveals that the dying Sun will destroy the asteroid belt as we know it and also effect the asteroid beyond Neptune and Pluto.

Scientists have predicted that around six billion years from now, the Sun will run out of fuel and die. However, researchers have found out that before the Sun calls it quit, it will expand massively and emit powerful electromagnetic radiations in the process which could pulverize the solar system’s asteroids.

According to a study published in the Monthly Notices of the Royal Astronomical Society, the radiation given off by stars like our sun in their death throes can spin asteroids to such high speeds that they break apart into successively smaller fragments.

Around 90 per cent of the stars in the universe, including our own Sun, are “main sequence” stars. When these stars use up all of their hydrogen fuel they balloon to hundreds of times their normal size. This phase — known as the “giant branch” — lasts a few million years, which is too short in cosmic terms.

During this time, the stars not only grow in size but also experience a huge increase in their luminosity while they emit electromagnetic radiation. As per the study, the inflated stars then shed their expanded outer layers and collapse into a dense remnant– known as a white dwarf.

According to the lead authors of the paper, Dimitri Veras from the University of Warwick in the UK and Daniel Scheeres at the University of Colorado, the increasingly intense radiation emitted by main-sequence stars during the “giant branch” phase will be absorbed by asteroids.

As per the study, this radiation will be redistributed internally and then emitted from a different location within the asteroid. It will create an imbalance, which in turn will create a torque effect gradually spinning up the asteroid. This will lead them to break-up speed at one full rotation every two hours. This effect is known as the YORP effect, named after four scientists — Yarkovsky, O’Keefe, Radzievskii, and Paddack — who contributed ideas to the concept.

Source: Indian Express, 12/02/2020

Scientists identify seven universal moral rules

Oxford researchers have identified seven universal moral rules common around the world, suggesting that people across cultures live by the same basic ethical codes and values. The rules include helping your family and group, returning favours, being brave, deferring to superiors, dividing resources fairly, and respecting others’ property. Previous studies have looked at some of these rules in some places – but none has looked at all of them in a large representative sample of societies. The study, published in Current Anthropology, is the largest and most comprehensive crosscultural survey of morals ever conducted, researchers said. The team from University of Oxford in the UK analysed ethnographic accounts of ethics from 60 societies, comprising over 600,000 words from over 600 sources. “The debate between moral universalists and moral relativists has raged for centuries, but now we have some answers,” said Oliver Scott Curry, senior researcher at Oxford. “People everywhere face a similar set of social problems, and use a similar set of moral rules to solve them,” said Curry. “As predicted, these seven moral rules appear to be universal across cultures. Everyone everywhere shares a common moral code. All agree that cooperating, promoting the common good, is the right thing to do,” he said. The study tested the theory that morality evolved to promote cooperation, and that – because there are many types of cooperation – there are many types of morality. The research found that these seven cooperative behaviours were always considered morally good. Examples of most of these morals were found in most societies. Crucially, there were no counterexamples – no societies in which any of these behaviours were considered morally bad, researchers said. The study also detected “variation on a theme” – although all societies seemed to agree on the seven basic moral rules, they varied in how they prioritised or ranked them. The team has now developed a new moral values questionnaire to gather data on modern moral values, and is investigating whether cross-cultural variation in moral values reflects variation in the value of cooperation under different social conditions.

Source: Midday, 14/02/2019