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Why can t we bounce radar signal off the sun and determine 1 au directly

 

On April 7, 1959, a three-member team led by Stanford electrical engineer Von R. Eshleman recorded the first distinguishable echo of a radar signal bounced off the sun. A.S.Ganesh tells you more about Eshleman and how his team achieved this success…

When we generally say “reach for the stars,” we use it as a phrase to convey having high or ambitious aims. Some people, however, reach for the stars in the real sense. Stanford electrical engineer Von R. Eshleman was one of them and the star he reached out for was our sun.

Born into a farming community in Ohio, U.S. on September 17, 1924, Eshleman attended the General Motors Institute of Technology in Flint, Michigan, while still being a high school student. Similarly, even before earning his bachelor’s degree in electrical engineering from George Washington University in 1949, he started attending Ohio State University.

Intrigued by wave science

Before this, he had a stint with the navy during World War II, working as an electrical technician from 1943-46. It was during this period that he was drawn towards wave science. Intrigued by both sonar and radar, Eshleman had the idea that he could bounce radio signals off the surfaces of the sun and the moon, in order to study their hidden structures. While his own ship-based experiments of the time weren’t successful, they paved the way for his future research.

Having received his master’s degree from Stanford in 1950, he went on to earn his Ph.D. in 1952. He was recruited by Stanford to be a research professor, a position he held until 1957, when he was promoted to the teaching faculty as an Assistant Professor (Associate Professor back then). By 1962, he had not only managed to bounce radar off the sun, but also became a full professor at Stanford.

The same war that had planted the idea in Eshleman’s mind for bouncing radar off surfaces also saw the rapid development of radar. Bouncing radar off distant surfaces wasn’t an idea exclusive to Eshleman. Radar was successfully bounced off the moon in the 1940s itself and the first attempts to bounce radar off Venus were made in the late 1950s, albeit with mixed results.

16-minute round-trip

Eshleman’s three-member team, including Lt. Col. Robert C. Barthle and Dr. Philip Gallagher, achieved success in bouncing radar off the sun on April 7, 1959. The tests, in fact, were run on April 7, 10 and 12, with an average time of 16 minutes and 32 seconds spent for the signals to travel the 149 million km distance between the Earth and the sun and back again.

The researchers needed many months to confirm that they had indeed succeeded and when they finally made their announcement public with a press conference in February 1960, it was with 99.999% certainty.

Coded pulse

Eshleman had explained to the gathered media persons that the radar antenna consisted of 5 miles of wire that was spread out across over 10 acres of land, and a 40,000 watt transformer.

Every time the test was conducted, a coded pulse was beamed at the sun in 30-second bursts. This was done to enable identification once it returned after bouncing off the sun.

While 40,000 watts were sent out, atmospheric and spatial dissipation meant that only about 100 watts reached the sun. Similar losses during the return journey meant that only a miniscule amount of energy returned, making detection difficult. The task was further complicated by the fact that this small amount of energy was now part of the vast amounts of similar energy that the sun itself radiates. The other wavelengths. By spending over six months with some of the best computers of the time, they were able to conclude that the coded pulse that they sent out was among the radio emissions of the sun.

In 1962, Eshleman, along with Stanford colleagues, founded the Stanford Center for Radar Astronomy to oversee radio experiments. Even though he began his career in radar astronomy, Eshleman is now best remembered for his pioneering work using spacecraft radio signals for precise measurements in planetary exploration. While he briefly served as Deputy Director of the Office of Technology Policy and Space Affairs in the U.S. Department of State, he was most comfortable among academic circles and hence returned to Stanford, where he flourished. Eshleman died in Palo Alto on September 22, 2017, five days after turning 93.

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What is the Pandemic Accord

GENEVA, SWITZERLAND: When the world was shaken by Covul-19 which shredded economies. Overturned societies, crippled health systems, and killed millions of people-many countries came together and decided to build a framework of binding commitments to stop such such trauma from ever happening again. This happened in 2021

Since then, countries have been holding talks to make this happen but the talks have been caught in many issues. The final round of talks is happening this week, but countries are not even close to maching a deal that is acceptable to all parties.

World Health Organization [3:50 pm, 8/4/2024] IIFL: chief Tedros Adhanom Ghebreyesus has repeatedly warned nations that “everyone will have to give something, or no one will get anything.”

 

Who wants what?

European countries – who led calls for a pandemic treaty want more money invested in pandemic prevention, while African nations want the knowledge and financing to make that work, plus proper access to pandemic “counter-measures” like vaccines and treatments.

The United States wants to ensure all countries share data and samples from emerging outbreaks quickly and transparently, while developing countries are holding out firm for guaranteed equity to stop them getting left behind.

According to the roadmap, a finalised accord on pandemic preparedness, prevention and response would be adopted at the May 27 to June 1 World Health Assembly of the WHO’S 194 member states

Issues at hand

The main topics still in play include access to emerging pathogens, better prevention and monitoring of disease outbreaks, reliable financing and transferring technology to poorer countries. The talks are being conducted by an Intergovemmental Negotiating Body.

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Where did Homo sapiens go after leaving Africa?

WASHINGTON us. Human beings first emerged in Africa more than 3;00.000 years ago they began migrating out of the continent about 60,000- 70.000 years ago. But, where did they go after they left Africa? After years of debate a new study has some answers to offer. According to it these hunter-gatherers appear to have lingered for thousands of years as a homogenous population in a geographic hub that spanned Iran, parts of Iraq. And Saudi Arabia before going to settle in all of Asia and Europe about 45,000 years ago.

 

These findings are based on genomic datasets drawn from ancient DNA and modern gene pools, combined with palaeoecological evidence that showed that this region would have represented an ideal habitat. The researchers called this region, part of what is called the Persian Plateau, a “hub” for these people who numbered perhaps only in the thousands before they continued onwant to more distant locales.

“Our results provule the first full picture of the whereabouts of the ancestors of all present-day non-Africans.” said Luca Pagani, senior author of the study. The combination of genetic and pale ecological models allowed us to predict the location where early human populations first resided as soon as they eated Africa,” said co-author Michael Petraglia.

How they lived

These people lived in small mobile bands of huntergatherers, the researchen said. The hub location offered a variety of ecological settings. From forests to grasslands and savannahs, fluctuating over time between arid and wet intervals. There would have been ample resources available with evidence showing the hunting of wild gazelle, sheep and goat Petraglia said.

Their diet would have been composed of edible plants and small to large-sized game

Hunter-gatherer groups seemed to have practised a seasonal lifestyle laing in the lowlands in the cooler months and in the mountainous regions in the warmer months.” Petraglia said. The people inhabiting the hub at the time apparently had dark skin and dark hair, Pagani said their eventual dispersal in different directions set the basis for the genetic divergence between present-day East Asians and Europeans, the researchers said

Homo sapiens was not the first human species to live outside of Africa-induding the area encompassing the hub Neanderthals are attested in the area before the armsal of Homo sapiens. The hub may have been where the two species met.

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What is Charles Dickens famous for?

Discover the spellbinding world of Demon Copperhead, Barbara Kingsolvers award-winning novel that echoes Dickens’ timeless themes of poverty, survival, and the transformative power of storytelling.

 

About the author

parban Kingsolver o an American writer and political activist renowned for her powerful novels that delve into the resilience of individuals navigating challenging environments and finding beauty amidst hunh drcumstances in 2000, she founded the Bellwether Prize, a literary award aimed at proinoting works that drive social change. Having grown up in rural Kentucky US, and briefly livest in Africa during her early childhood, Kingsolver draws inspiration from diverse backgrounds

Becoming a writer

Her writing journey began in the mid-1980s when she worked as a science writer for a university, eventually transitioning into freelance feature writing It was a timing point when she won a local Phoenix newspapers short stong contest, leading her to pursue a full-time career in fiction writing.

Throughout her career. Kingsolver has produced influential works that have captivated readers worldwide. Some of her notable novels include The Bean Trees (1988) The Poisonwood Bible (1998). The Laqura (2009), and Demon Copperhead (2022) Vintage engraving of a scene from the Charles Dickens novel David Copperfield llustration by Fred Bamard GETTY IMAGES

Making history

Kingsolver recentlig auded more feathers to her literary cap with Do prestigious awards celebrating her novel Demon Copperhead Notably she became the first author to win the Women’s Prize for Fiction bvice having previously receives the honour in 2010 for her autaimest work. The Lacuna. This modem reimagining of Charles Dickens’s David Copperfield is set in the picturesque Appalachian Mountains of Virginia, where the protagonist. a lroy bom in a trailer park embarks on a journey filled with foster care, labour exploitation, addiction, love. and heartache. Speaking about the book, she shared that much Like Dickens, the crafted her novel to shed light on the hardships of poverty and its impact on children, issues that have plagued our society for centures The Women’s Prize for Fiction recognises outstanding. ambitious original fiction” written in English by female writers from around the world. Continuing her winning streak, Kingsolvers modem reimagining of English author Charles Dickens’s classic won the fiction category of the James Tait Black Prize this year. This illustrious literary award. established in 1919 and presented by the University of Edinburgh, holds the distinction of being one of the UK’s longest-running and most esteemed accolades. What sets this prize apart is its unique judging panel, consisting of literature scholars and students. ensuring a deep appreciation for the art of writing.

When inspiration strikes

During an interview Kingsolver shared the story behind the inception of her Latest novel She recounted a moment four years ago when she had just finished a book tour in the UK for her previous work Unsheltered and had a few days before her return flight home Seizing the opportunity, she and her husband decided to stay at Bleak House, a clifftop retreat perched above Viking Bay in Broadstairs, the very place where Charles Dickens had penned David Copperfield As fate would have it, they arrived during a hailstormy weekend in November, and the location was deserted. As she wandered through the rooms, curiosity led her to explore Dickens’s desk and gaze out over the saune magnificent coastline he once beheld in this atmospheric setting the spint of the great author seemed to reach out to her She recousted “Anil tvars when he said. Look to the child. Let the child tell the Inspired by this serendipitous encounter, the author entbarked on her literary journey, giving life to the novel Demon Copperhead Demon Copperhead Set in the mountains of southern Appaladin, Demon Copperhead follows the gripping story of a boy bom to a struggling teenage single mother facing the harsh realities of foster care, child labour, and heartbreak Written in the protagonists raw and unyielding voice. the novel addresses the invisibility of rural communities in a world fixated on urban glamour. Drawing inspiration from Charles Dickens’s David Copperfield Kingsolver weaves a tale of anger, compassion, and the transformative power of storytelling The journey of this titular character gives voice to a new generation of lost souls born into beautiful yet challenging places they can not fathom leaving behind.

David Copperfield

David Copperficial was first palaketa serial from 1840 to 1850 and later compiled its
it holds the distinction of bring English author Charles Dickens’s favourite anong his works
The novel u nimated in the first person by the protagonist, a Copperfield reflecting on his lifes journey Bons in Blunderstone Suffolk LIK, shortly after his fathers death Davul is raised by his mather and the caring housekeeper, Clara Peggotty. The story takes readers through David’s difficult upbringing under the cruel Mr Edward Mundstone (his stepfather) and his eventual adventures and self-discovery on the path to becoming a successful novelist. It is a poignant coming-of-age tale depicting a young man’s transformation from a challenging childhood to finding his purpose in life.

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