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The Story of Helium and the Birth of Astrophysics by Biman B. Nath

By Biman B. Nath

What if essentially the most exciting tales within the heritage of technology became out to be mistaken? Can city legends creep into the hallowed grounds of clinical historical past? As extraordinary because it may perhaps sound, the tale of 1 of crucial parts nowa days – helium - has been frequently misrepresented in books, encyclopedias, and on-line resources, although archival fabrics inform a distinct tale. Open the access for Helium in any encyclopaedia and you'll learn a fake tale that has been repeated through the years. ‘Encyclopaedia Britannica’, for instance, says that helium was once found by means of the French astronomer Pierre Janssen whereas watching a complete sun eclipse from India in 1868. it seems that he spotted whatever new within the spectrum of the solar, which he proposal used to be the signature of an undiscovered point.

The fact is that Janssen by no means observed any signal of a brand new aspect in the course of his observations in India. His reviews and letters don't point out this sort of declare.

Other resources could have you ever think that helium was once together stumbled on via Janssen and Norman Lockyer, a British scientist, and that their discovery letters reached Paris an analogous day, one despatched from India, and the opposite from England.

Again, the fact is totally different. letters from Lockyer and Janssen did achieve Paris an identical day in 1868, yet their letters didn't point out any new aspect. What they'd found used to be a brand new manner of watching the solar with out a sun eclipse. this could eventually bring about the invention of helium, during which Lockyer might play a widespread position, yet no longer Janssen.

At a similar time, Norman Robert Pogson, a disgruntled British astronomer stationed in India did discover anything unusual throughout the eclipse. He was once the 1st one to note whatever bizarre in regards to the spectrum of the sunlight that day, and his observations may end up an important to Lockyer’s personal investigations of helium. yet Pogson’s document was once by no means released in any peer reviewed magazine and it languished at the table of a neighborhood British officer in colonial India.

This publication tells the genuine tale in the back of the invention of helium, in addition to biographical sketches of the scientists and outlines of the milieu during which they labored. it's going to express the thrill, confusion, and keenness of 19th century scientists, utilizing their very own phrases, from their letters and reviews.

“The tale of Helium and the beginning of Astrophysics” chronicles essentially the most intriguing discoveries ever made and explains why it additionally marked the start of a brand new department of technology known as ‘astrophysics.’

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In other words, there would appear a dark line. Therefore the condition for the reversal is this: the absorbing material must be at a lower temperature than the radiating object. Bunsen’s student Roscoe came down to visit them in Heidelberg in 1860, and he later recounted his impression after hearing about the work: I had already left Heidelberg when the two friends began their classic research on spectral analysis. But when I returned 42 The Story of Helium and the Birth of Astrophysics to Heidelberg in the summer of 1860, I studied this work in great detail and translated it from Poggendorf’s Annalen for the Philosophical Magazine.

Sir William Crookes would have an important role to play in the coming years in our story of helium, and his experiments would provide a crucial piece in the jigsaw puzzle that kept scientists busy for almost half a century. Two years later, Ferdinand Reich, a German physicist and his assistant, Hieronymous Theodor Richter, discovered yet another element by the Kirchhoff-Bunsen method. They were actually looking for thallium, which Crookes had discovered two years before, and were trying to isolate the new metal with chemical means.

He used his theodolite telescope to study the spectra of bright stars and planets, such as Venus and Sirius. ” The spectra of stars were somewhat different, though. He wrote: “I have seen with certainty in the spectrum of Sirius three broad bands, which appear to have no connection with those of sunlight; one of these bands is in the green, two are in the blue. ”7 These dark lines were a mystery. It was as if certain parts of sunlight were missing, certain colors were being withheld. If that was so, then what was causing it?

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