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D.D. Kosambi
Blog dedicated to the life and works of the path breaking Indian historian and mathematician.
D D Kosambi: Selected Works in Mathematics and Statistics by Ram Ramaswamy
Re-posted from: And then...
After what seems an agonizingly long time since the first ideas of the book took root, I got the following letter from my publishers (how sweet that sounds!) last week,
"We are very pleased to inform you that your book has been published and it is available on http://tinyurl.com/jgn2djj. Customers can order it […] etc."
D D Kosambi: Selected Works in Mathematics and Statistics is finally done, and is now available in both e and paper formats. The cover on the right shows DDK at three stages of his life, at Harvard, in Aligarh, and finally, in his TIFR years.
To quote from the blurb: This book fills an important gap in studies on D. D. Kosambi. For the first time, the mathematical work of Kosambi is described, collected and presented in a manner that is accessible to non-mathematicians as well. A number of his papers that are difficult to obtain in these areas are made available here. In addition, there are essays by Kosambi that have not been published earlier as well as some of his lesser known works. Each of the twenty four papers is prefaced by a commentary on the significance of the work, and where possible, extracts from technical reviews by other mathematicians.
My personal contribution to the book, other than to edit is, is fairly minimal. Apart from a preface, I have basically tried to describe the academic milieu in which Kosambi found himself at different points in his life, and have also tried to infer what others thought of him in another prefatory essay, "A Scholar in His Time".
Kosambi gave his academic manifesto in the essay, "Adventure into the Unknown" which also is one of the places where he wrote that Science is the cognition of necessity. (It is quite another matter that the phrase is not one that can be understood in a straightforward manner. Anyhow, as a quote its famous enough.) Reprinting that essay in its entirety seemed appropriate, as also another note "On Statistics" that gives a flavour of DDK's interdisciplinarity, mixing statistics, erudition, Marxism, etc. The last of the non-mathematical writings is a project completion report submitted by DDK to the Tata Trust in 1945 and it permits, among other things, an inner view of a vastly gifted and somewhat frugal scholar who, in parallel, and for Rs 1800, carried out 6 research projects on issues as diverse as writing a mathematical monograph on Path Spaces, editing a concordance of Bratrihari's epigrams, and constructing an electromechanical computational device (the Kosmagraph), among others.
The remainder of the book is a set of reprints. Of his 67 or so papers in mathematics and statistics, about a third are presented, starting with some of his first papers, Precessions of an Elliptical Orbit and On a Generalization of the Second Theorem of Bourbaki, and ending with one of the papers he wrote under the peculiar alias of S. Ducray, Probability and Prime Numbers.
An attempt was made to include all the important papers, in particular the ones that made his reputation such as Parallelism and Path-Spaces that along with two other notes by Cartan and Chern are the basic of the Kosambi-Cartan-Chern theory, the various papers that laid the foundations of scientific numismatics, as well as the papers that he should have followed up but didn't, such as Statistics in Function Space that foreshadowed the K-L decomposition. The Kosambi distance in genetics was elaborated in The Estimation of Map Distances from Recombination Values, and this is also reprinted.
Kosambi's obsession with a statistical approach to the proof of the Riemann hypothesis resulted in several papers of which An Application of Stochastic Convergence, Statistical Methods in Number Theory, and The Sampling Distribution of Primes are reprinted here. These, as is well-known, effectively ruined his reputation as a serious mathematician.
Chinese. Japanese. French. German. English. DDK published papers in all these languages, sometimes exclusively, and twice the same article in translation. Also reprinted in this volume are three of the foreign language papers, the ones in German, French, and Chinese. The last is of particular interest since it was written during an exchange visit to China in the late 1950's and only later published in English.
A number of people have helped me along the way and it is my pleasure to thank them all here. For the initial suggestion that the book be done, and for sustained and general encouragement, I am very grateful to Romila Thapar. I've written about this before. Meera Kosambi was keen to see her father's mathematical legacy appreciated and was very enthusiastic about bringing out this collection and helped greatly in more ways than I can describe. She passed away in January 2015, when she knew the project was afoot, but not in any way certain as to how it would all come out. Michael Berry, S. G. Dani, and Andrew Odlyzko discussed and advised on various points of the mathematics. Indira Chowdhury and Oindrila Raychaudhuri helped vis-à-vis archival matters. Rajaram Nityananda had had many of DDK's papers digitized, a great boon, and one that made the reproduction of some material much easier! Kapilanjan Krishan, Rahim Rajan, and Mudit Trivedi helped me locate some of the more obscure of DDK's papers. K. Srinivas retyped almost all the papers, and Cicilia Edwin painstakingly proofread most of them. Toshio Yamazaki and Divyabhanusinh Chavda told me of their interactions with DDK, helping to flesh out the personality. Finally, Aban Mukherji was gracious with permissions, as were all the journal editors who kindly permitted the several articles to be reprinted.
DDK maintained a charmingly frank notebook diary during his Harvard years. On the 19th of January 1927 he notes: A most restless day. I have forgotten to mention Monday the 17th and an important conference with Birkhoff thereon […] Problems: Fermat's Last Theorem, the Four color map, the functional equation […] Today was unusually restless with a great deal of time spent, possibly wasted in the Widener. Looked up old issues of Outing, Shakespear's Hindi Readers, most of Burton's works [of him more later], Roosevelt on African and Brazilian 'sporting' – worthless – Stefansson's excellent and much remembered 'Friendly Arctic'…
All this variety in a single day! To recall Wordsworth, Bliss indeed it was in that dawn to be alive! Kosambi, just out of his teens, was just bursting with energy, both intellectual and physical (for which one must read the diaries in some detail). The earnestness that only comes at that age shines through on the pages quite unselfconsciously:
Exuberance indeed, but also some simplicity: Deep interest, well sustained, is essential in the acquisition of knowledge upon any subject. And the third realization of the day: Life is good. Yes indeed, to be young was very heaven.
D D Kosambi: Selected Works in Mathematics and Statistics is published by Springer. ISBN: 978-81-322-3676-4
Posted by readerswords at 7:22 AM No comments: Links to this post
Labels: mathematics
Sandesh Kadur talk at festival of ideas
PANAJI: With a camera in hand and a mind full of wonder, Sandesh Kadur would often cycle to the outskirts of Bengaluru to shoot images of the wilderness.
Back then, little was he aware that on a given night, the sounds of a Nightjar bird and the sawing call of the leopard would soon lead him on a path dedicated to documenting animals for NatGeo, discovering new species and saving the endangered ones.
An award-winning wildlife photojournalist and documentary filmmaker, Kadur, through the use of still images and videos, is known for advocating the need for conservation and protection of the planet's biodiversity.
Speaking on day one of the 10th D D Kosambi Festival of Ideas on Monday, he shed light on the forested valleys and snow-covered peaks of the Himalayas besides commenting on burning issues of Goa's biodiversity.
"Less than 5% of India's land mass is protected forest area, which is very little. We need to stop with the assault on our green areas and start conserving them," he urged.
His tryst with wildlife has led to the discovery of several new species that are endemic to the mountain regions. "Over 564 species were found until 2014 and they are being discovered on a continuous basis in the Himalayas," he said.
This, in turn, has also led to the shattering of myths about certain animals in India. He explained this through his picture of a tiger scavenging on the carcass of a rhino.
"The image has shattered all romantic stories about a tiger being a gentlemanly creature that feeds on his own kill," he explained.
His expeditions also led him to capture peaks of the Western Ghats in light as well as shadow, a rare sight of purple frog, a foot-flagging frog, purple Nilakuranji flowers that bloom once every 12 years, among others; images of which he showcased to the awe-struck audience in the packed auditorium.
A firm believer of free rivers, Kadur stressed on the need to let water bodies flow sans restriction, "Mountains harness the power of monsoon and create rivers. If we stop that by building dams, it will affect the ecosystem. There are countries removing dams therefore and making rivers free again because they realise that hydropower is not as green".
Sharing his thoughts on the Goa-Karnataka battle over the Mhadei issue, he said, "Rivers initially were protected in the birth places by temples but now they're being affected by too much 'love.' During the riots and bandhs in Bengaluru and Chennai due to Mhadei issue, it was estimated that there were losses of over Rs 25,000 crore per day. If that money had just gone to protect these rivers we wouldn't have to fight over rivers and have a positive impact on the environment".
Elaborating further, he said that building dams do more harm than good, "Respecting rivers and allowing them to flow as they are is very important. Damming them or curtailing them or diverting them can affect everything downstream. Stopping the river from flowing into the ocean gradually leads to a multitude of fish species being destroyed as well."
Kadur also commented on the state's potential for hinterland tourism. "Tourism is a very economic one-way game but that's the shortsighted view. We need to bring about tourism in the most responsible and low-impact manner. If we can bring that about then we can save those places while showcasing them to visitors. We also need education by way of an interpretation centre at the tourist spot so that experts can explain to people the value of the place."
He further pointed out that hinterland tourism should be within a certain limit so as to not cause imbalance in the natural surrounding. "We need to spread out the tourism and have less people in each place instead of too many in one place. Thus keep the density of tourism low and not go beyond the place's carrying capacity."
Source: Times of India
Posted by readerswords at 12:33 PM No comments: Links to this post
Labels: Festival of Ideas
D D Kosambi Festival of Ideas sees diverse line-up
Wildlife photographer Sandesh Kadur
PANAH: The 10th edition of D D Kosambi Festival of Ideas is scheduled to be held from February 13 to 17 at Kala Academy, Panaji.
This year will also have an impressive line-up of stalwarts from various fields who will conduct intellectually stimulating sessions for the Goan audience. Speakers this years are National Geographic explorer and wildlife photographer, Sandesh Kadur who will speak on India's mountains of life on February 13; while professor at Tata institute of fundamental research, Mumbai, Shubha Tole, will speak on 'wiring up the brain' on February 14.
A professor at Newcastle University, UK, Sugata Mitra will speak on the future of learning on February 15. Professor of international mental health and welcome trust principal research fellow in clinical science, UK, Vikram Patel will speak on 'People's health in people's hands: Reimagining health care' on February 16. The concluding session on February 17 will be by founder, BoP HUB, world toilet organization, Jack Sim. He will speak on creating a global movement for sanitation. Live telecast of the lectures will be screened on local channels as well as on the website of directorate of art and culture.
'Experts over celebs' at Kosambi festival this year
Panaji: Experts with great oratory skills have been given priority over celebrity status at the 10th edition of DD Kosambi Festival of Ideas, that will be inuagurated on February 13 at 5pm at Kala Academy.
"Over the decade, we have had to attract crowds by inviting glamourous speakers. But this year, we have given importance to good orators over celeb quotient. These speakers will deliver strong content in their talks," said art and culture director Prasad Lolyekar.
The festival will open with Sandesh Kadur's talk on India's mountains of life on February 13. An award-winning wildlife photojournalist and documentary filmmaker, Kadur, through the use of still images and videos, exposes the need for conservation and protection of the planet's biodiversity.
On February 14, Shubha Tole, a neuroscientist whose research involves investigating the development and evolution of the mammalian brain, will speak on 'wiring up the brain'.
Sugata Mitra, known for his 'Hole In The Wall' experiment wherein a computer was embedded in a Delhi slum wall in 1999 for children's use, will speak on the future of learning on February 15.
Co-founder of NGO Sangath, Vikram Patel will speak on 'people's health in people's hands: reimagining health care' on February 16. Patel was listed in TIME Magazine's 100 most influential persons of the year in 2015.
The concluding session on February 17 will be by Jack Sim, who founded the World Toilet Organization in 2001. Sim, widely known as 'Mr Toilet' for breaking the taboo around sanitation, will speak on creating a global movement for sanitation. It is due to Sim's efforts that November 19 has been declared as UN World Toilet Day.
The festival will be inaugurated by IAS officer Daulat Hawaldar.
Source: The Times of India
'Govt must honour D D Kosambi': GN Devy
TNN | Updated: Nov 20, 2016, 11.10 AM IST
MARGAO: Stating that Buddhist scholar and Pali language expert D D Kosambi, who had no formal education, was the most original thinker the country had seen in the last 500 years. Literary scholar and cultural activist, G N Devy said the Goa government must consider setting up a centre in his name.
"It was he who introduced B R Amedkar to Buddhism and who introduced Marxism to India. India wouldn't have known about the ancient Pali language, if it wasn't for Kosambi who revived it. He made the entire world his domain for thinking," Devy said, adding that a centre named after him will be a great contribution to his legacy.
Posted by readerswords at 3:48 PM No comments: Links to this post
Confusing history with myth: Why ICHR should stick to history
Scholars have written copiously on the foolishness of discounting the role that myths play in understanding life and society, and the value of fiction, stories and tales passed on.
Written by Seema Chishti | New Delhi | Updated: August 18, 2016 8:38 pm
In legendary historian DD Kosambi's excellent work on ancient India titled 'Myth and Reality' (1962), he writes about his essays, almost as if for 2016 India; "they are based upon the collation of field-work with literary evidence. Indian critics, whose patriotism outstrips their grasp of reality are sure to express annoyance or derision at the misplaced emphasis.."
Broadly defined as a story of the past, history has come to mean much more. In a society which is so diverse, it has often come to mean very different things to different people. History is a story that needs to be told cautiously sometimes but nevertheless must be told, taught and studied.
The bid of the Indian Council for Historical Research (ICHR) to announce that it is now going down the route of collecting detailed "folklore", "custom" and "only documenting what is heard", about the very distant past, appears fraught with monumental issues.
Scholars have written copiously on the foolishness of discounting the role that myths play in understanding life and society, and the value of fiction, stories and tales passed on. To be unmindful of prevalent legends would leave us the poorer in comprehending much harder material truths. But problems begin, when legends, myths and history are all sought to be confused.
The function of recording, teaching or studying History, is surely to learn lessons from the past, to be familiar with compatriots, to learn and unlearn about other lives, or at least that is the purpose we hope history serves for us, when taught in schools and beyond.
Historiography is serious and contested terrain but ground rules about what constitutes evidence and what hearsay suggests that it is very important that the difference be maintained.
There is no harm therefore in knowing about myths and legends, but to be able to tell clearly what a piece of pottery, jewellery, a grave or a monument or cooking utensils tell you about people long gone before us should be a priority in a vast and old civilisation like ours.
History is more important, when governments are involved in writing (and rewriting) textbooks. Textbooks being among the most useful ammunition to control young minds. The1980s phase in our neighbouring state of Pakistan survives uptil today in dangerously altered textbooks, or how history is studied in middle-schools. A recent project by two Pakistani scholars, Qasim Aslam and Ayyaz Ahmed, studies how differently Indian and Pakistani textbooks, learn about exactly the same facts. Not that India has got it all right, but the necessity of feeding myths to Pakistan was such a dominant idea there, that History was firmly pushed out of the frame.
Myths, being privileged over history writing, have been known to serve a useful political purpose. The myth of Aryan supremacy would have been a useful account to spin support for the Nazi view of the world in its time. When the 'superiority' of White-skinned plunderers in Africa had to be established, myths and legends, hearsay and anecdotes over years would have been a useful tool to establish why it was the way things should be. Which of us has not heard a story whispered at a monument which says the exact opposite of what we have known to be a recorded fact about the monument/area/people?
If only to avoid history from repeating itself, either as tragedy or a farce, it may be well worth the while of institutions like ICHR, tasked with serious historical research to do exactly that. Myths have a place, but for India to have a functional present and future, they must not be confused with history.
Posted by readerswords at 11:49 AM No comments: Links to this post
Labels: Indian History
'Kosambi memory' today
Source: The Hindu
The Centre for Gandhian and Peace Studies, Manipal University, in association with Centre for Vedic and Linguistic Inquiry will organise a seminar titled 'Kosambi memory' here on July 2 in memory of the late D.D. Kosambi, historian, mathematician, numismatist, and statistician.
A press release here on Thursday said that the seminar was being organised on the occasion of Prof. Kosambi's 50th death anniversary.
The speakers will include K.P. Rao, founder-director, Centre for Vedic and Linguistic Inquiry, Manipal, Surendra Rao, retired professor of History, Mangalore University, and Varadesh Hiregange, Director, Centre for Gandhian and Peace Studies.
The seminar will begin at 10.30 a.m. at LH 1, first floor, Old TAPMI building.
Labels: Remembering Kosambi
Kosambi was not an 'official Marxist', says historian
K.P. Rao, software expert and Director of Centre for Vedic and Linguistic Inquiry, speaking at a seminar on D.D. Kosambi in Manipal.
B. Surendra Rao, retired Professor of History, Mangalore University, has said that though the late D.D. Kosambi used Marxist notions of history, he was not a reductionist.
He was speaking on 'D.D. Kosambi's contribution to history', a seminar organised by the Centre for Gandhian and Peace Studies, a constituent of Manipal University, and the Centre for Vedic and Linguistic Inquiry, here on Saturday.
According to a press release issued here on Sunday, Prof. Surendra Rao said that Kosambi considered himself a Marxist, but "official Marxists" did not consider him as a Marxist. In this context, the differences between Kosambi and S.A. Dange were worth noting, he said.
A historian was one who looked at the present rooted in the past. Myth was a different order of reality. Socialism would not be redundant so long as there was socio-economic injustice.
In his 'Exasperating Essays' and 'Myth and Reality', Kosambi was precisely trying to make use of this perspective. Eminent historians such as Romila Thapar and Irfan Habib had profusely acknowledged Kosambi's contribution to history, Prof. Rao added.
K.P. Rao, software expert and Director of Centre for Vedic and Linguistic Inquiry, said that about five decades ago, Kosambi argued in favour of solar energy against atomic energy even while working with nuclear scientist Homi J. Bhabha.
Recalling his memories and association with both Kosambi and Bhabha, Prof. K.P. Rao said that Kosambi was then itself quite concerned about the "rise in temperature" of the world. It was Kosambi's hope that sun being the "natural source of energy" was the way forward. On this point, he parted ways with Bhabha in Tata Institute of Fundamental Research, he said. Responding to the view that Kosambi was a Marxist, Prof. K.P. Rao said, "If this is Marxism, then Marxists are welcome."
Varadesh Hiregange, Director of Gandhian and Peace Studies, who delivered a lecture on Prabhaker Acharya's essay on Kosambi's thesis with regard to 'Urvasi myth of Rigveda', said Kosambi's approach to Rigveda was anthropological.
Make hay while the sun shines!
by KULDEEP KUMAR
Source: The Hindu 13th May 2016
D.D. Kosambi's essays aptly titled "Adventures into the Unknown" reveal how the scientist pushed for solar power more than half-a-century ago when the world was busy playing with atoms
Believe it or not, India has set an ambitious target of adding 100 gigawatts of solar power by 2022. Before the Paris Climate Summit, it had pledged that by 2032, it would increase its share of non-fossil fuels to 40 per cent of the total power generation capacity. These decisions have come many years after India under the leadership of Prime Minister Manmohan Singh had signed the controversial civil nuclear agreement with the United States with a view to meet its energy requirements. So, clearly, solar energy is the flavour of the season.
This reminds me that there was a time in the 1950s and early 1960s when those who advocated solar energy could be pitted against the scientific and technological establishment of the country and viewed with suspicion. D. D. Kosambi, a polymath genius who made seminal contributions in pure mathematics, quantitative numismatics, Sanskrit studies and the study of ancient Indian history and culture, was one such individual who came in direct conflict with the Department of Atomic Energy because of his strong views against the use of nuclear energy as he favoured solar energy in its place. He also had to cross swords with Homi Jehangir Bhabha, widely recognised as the father of the Indian atomic energy programme.
It was Bhabha who had invited Kosambi in 1945 to join the recently established Tata Institute of Fundamental Research (TIFR) and help set up the School of Mathematics. In the initial years their relations were very cordial (as it is clear from Kosambi's scribble on the newspaper cartoon that he forwarded to Bhabha) but soon differences cropped up as Kosambi emphasised that a country like India that received sunshine in abundance must place greater reliance on solar energy. That he was a die-hard Marxist, who was very active in the international peace movement, did not help matters.
In the 1950s, the Department of Atomic Energy had started funding TIFR and Kosambi's continuance there became untenable. Moreover, the fact that he had also emerged as a major historian who had brought about a paradigmatic shift in the study of ancient Indian society also made his fellow scientists view him with suspicion as his non-scientific interests were not considered compatible with his senior position in TIFR.
Recently, Three Essays Collective brought out a collection of Kosambi's essays titled "Adventures into the Unknown". Ram Ramaswamy, Professor of Physics at the Jawaharlal Nehru University, has edited this volume that contains hitherto unpublished material. In his preface, Ramaswamy informs that in 1960 Kosambi gave a talk to the Rotary Club of Poona and the text has been published here as "Atomic Energy for India". In this essay, he underlines the need for research and development in the field of solar energy, a need to which our government seems to have woken up only recently. "Solar energy," Kosambi says, "is not something that any villager can convert for use with his own unaided efforts, at a negligible personal expenditure, charkha style. It means good science and first-rate technology whose results must be made available to the individual user." Nuclear disasters like Chernobyl and Fukushima have proved visionaries like Kosambi right.
In 2013, Prof. Meera Kosambi, the sociologist daughter of D. D. Kosambi, edited a book that contained writings of her as well as on her father. Titled "Unsettling the Past", it was published by Permanent Black. It also contains two other essays of Kosambi on the question of solar energy that were written between 1957 and 1964. In "Sun or Atom?", Kosambi draws our attention to the fact that scientific and technological research in the developed world is inextricably tied to the military-industrial complex and therefore solar energy was being ignored.
He says, "The research is of no use for war purposes. That is why it attracts some of us, but does not attract those who control the funds." In another essay "Solar Energy for Underdeveloped Areas", Kosambi cites another reason why significant technological advances were not being made to solve the problem of storage of solar energy: "The lands where technology is most advanced are just those which have very little sunlight as compared to India and Africa and where conventional forms of energy are highly developed." However, he was quite confident that ultimately solar energy would become affordable and gave the example of aluminium. "But extracting this metal was a most costly process and aluminium was, a century ago, costlier than gold. Technology has made the metal cheap…"
As India finally turns to solar energy, it is very refreshing to read these essays that were written more than half-a-century ago.
The writer is a senior literary critic
Labels: New Findings, Science
Government revises D D Kosambi Research Fellowship scheme
TNN | Apr 26, 2016, 10.46 AM IST
Panaji: The state government has revised the D D Kosambi Research Fellowship scheme. The objective of the scheme is to encourage Goan scholars to undertake research in the field of Goan history, culture, arts, social studies and related areas. Three fellowships, under the scheme, will be awarded every year by the state - at the junior level, at the senior level and at the post-doctoral level.
"Only topics that are closely connected to Goa will be accepted. However, authentic topics pertaining to Goa may also be considered for the fellowship depending upon the decision taken by the expert committee," the revised scheme document reads.
An individual who has completed post-graduation and is 35 and younger will be eligible to undertake research in the junior category. For the senior category an individual who has completed post-graduation and is above the age of 35 will be eligible. And for eligibility at the post-doctoral level, the individual will have to have completed PhD. There is no age bar for the third category.
"In case of exceptionally talented scholars of proven record with authentic work to their credit, the rules regarding educational qualifications may be relaxed, if recommended by the selection committee. The fellowship shall be awarded to any scholar only once in his lifetime under each category," the scheme states.
Eligible scholars for junior category will be awarded a fellowship up to Rs 10,000 per month for a maximum period of two years, on case-to-case basis. Scholars in the senior and post-doctoral category will be awarded a fellowship of Rs 20,000 per month for a maximum period of two years, again on case-to-case basis.
Every year, the department of art and culture will release an advertisement inviting applications for the "D D Kosambi Research Fellowship" for scholars and a selection committee constituted by the government will select scholars for the fellowship.
The project report in the form of two hard copies and a soft copy will have to be submitted within a period of 30 days after the completion of two years of the fellowship. The project submitted will be exclusively the property of department of art and culture, as per the scheme guidelines.
DD Kosambi
About DD Kosambi
Wikipedia Article on DD Kosambi
Introduction to this Blog
DDK's Books Online
Kosambi, Marxism and Indian History
(This article is taken from the 26 July 2008 EPW issue on DD Kosambi ( download pdf version ) By Irfan Habib (Irfan Habib is professor emer...
The Kosambi Effect on Indian Historiography
The Kosambi Effect: A Hermeneutic urn that shook Indian Historiography Rajan Gurukkal Source: EPW, 26th July 2008 Special Issue on DD Kosamb...
Essay on 'Indian Feudalism'
Read DD Kosambi's essay on 'Indian Feudalism' at google books (in Rural Sociology in India by AR Desai). Indian Feudalism diff...
A Discussion on Kosambi's work on Numismatics
Kosambi's book Indian Numismatics can be downloaded from here. Indo-Eurasian_research : Message: Re: [Indo-Eurasia] The Abrus precatoriu...
Early Indian History and the Legacy of D D Kosambi
Early Indian History and the Legacy of D D Kosambi Romila Thapar Published in the DD Kosambi special issue of EPW on 26th July 2008. Downlo...
Dharmanand Kosambi (11)
EPW's Special Issue on DDK (14)
Festival of Ideas (25)
Indian History (58)
Meera Kosambi (1)
New Findings (6)
Remembering Kosambi (71)
Carvaka for India
Economic and Political Weekly
Historical Mind
Indian Council of Historical Research
Kamat's Potpourri
Manas- History and Politics
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The Social Scientist
D D Kosambi: Selected Works in Mathematics and Sta...
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This document provides best practice guidance and a harmonised approach to the development and maintenance of inventories of hazardous materials in accordance with Article 5 and Article 12 of the...
EMSA Study on the use of Fuel Cells in Shipping
Fuel Cells are a promising technology in the context of clean power sustainability and alternative fuels for shipping. Different specific developments on Fuel Cells are available today, with research and...
Guidance for Ship Inspections under the Port Reception Facilities Directive (Directive 2000/59/EC)
The goal of this document is to provide a harmonised approach to the enforcement of Directive 2000/59/EC on Port Reception Facilities for Ship-Generated Waste and Cargo Residues (hereafter referred to...
Assists Member States in the implementation of forthcoming or newly adopted Legislation in the field of ship related pollution.
Assists the Commission, Member States and the maritime industry, where appropriate, in meeting, implementing and monitoring international and European legislation and initiatives on the reduction of SOx and NOx emissions.
Assists the Commission, Member States and the industry in the technical developments related to alternative fuels for ships as well as abatement methods.
Assisting the Commission, Member States and the Industry in the Implementation of the EU MRV CO2 Regulation as well as in the International context on future policy developments in this area.

redpajama_set_name: RedPajamaCommonCrawl


We have now entered what is statistically the worse month of the year for the stock market: September. The S&P 500 has lost 1.12%, on average, in Septembers dating back to 1928, according to Merrill Lynch Wealth Management. September has also been the worst month of the year for the Nasdaq and the Russell 1000 since 1971 and 1979, respectively, according to Jeffrey Hirsch of the Stock Trader's Almanac. In a recent post, Hirsch observed in post-election years going back to 1953 that "September is the third or fourth worst month depending on index." He calculates average post-election year September losses of 0.9% for the Dow Jones industrial average, the S&P 500 and the NASDAQ. The Russell 2000 has lost 1.6% on average in post-election Septembers.


Each custom order from Sea & Soul sets an entire team in motion.
After you place your order, Anna and our team of artists go to work getting all of the details just right – like size, area, color and important points on interest.
While the artist begins drawing your project, Bob and his team at the wood shop in Wisconsin start producing the frame and gathering the raw materials for your nautical art.
When the artwork is completed and approved, it is forwarded to the woodshop where it is laser engraved and cut. From there it gets sanded smooth and goes to assembly where stain color is applied and the chart is assembled by hand.
After assembly, your custom art goes to the finishing booth where a professional lacquer clear coat is applied to protect it. After assembly and finishing, the chart is now married to the previously completed and finished frame making it a completed heirloom to be enjoyed for years to come.
Kathy and the shipping crew meticulously package your nautical chart art for shipment and the process comes full circle back to you when you open your package and are overjoyed at what we have created together.


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Misinformation, distortion and half-truths: the innocent victims of reporting on Boston bombing
By Melissa Singer
April 20, 2013 — 6.22am
Staring into the face of a killer — alleged or convicted — is always confronting. Where does one begin to find answers to the immediate, burning questions: who is this person, and what motivated them to commit these heinous acts?
This morning, many people in Australia are waking to images of the alleged Boston Marathon bombers. What we now know, which we have wondered for days, is that police and the FBI are focusing their investigation on brothers Dzhokhar Tsarnaev, 19, and Tamerlan Tsarnaev, 26.
Residents watch as SWAT team members search for 19-year-old bombing suspect Dzhokhar Tsarnaev in Watertown, Massachusetts. Credit:Getty Images
The two men are believed to be Muslim, of Chechen origin, and have been in the US for at least one year.
The elder brother, Tamerlan, was killed in a firefight with police, possibly from gunshots and possibly from injuries sustained from explosives strapped to his body that he detonated in the stand-off. A policeman, Sean Collier, was killed in the crossfire.
As I write this, the younger brother, Dzhokhar, is still at large, having possibly escaped the 20-block search zone in a Honda, a car that before today had probably driven around Boston in complete anonymity. Reports now suggest it is carrying America's most wanted man.
These are the things we now know. But cast back to Friday evening Australian time and it was a very different story. Two different names, and two very different back stories.
I won't repeat the names here and risk adding to the smearing of two possibly completely innocent individuals. Besides, a quick internet search will yield all the information and its infinite quoting and requoting.
How these two names came to be the focus of the Twittersphere and media for several hours on Friday night is a product of our times. Kernels of information, when plugged into social media, take on a life of their own.
It is possible that the two names were broadcast on Boston police radio, but it is not clear now in what context. Armed with this information and the yearning for answers, it is understandable why social media went into overdrive.
But even though mainstream media tries to maintain a safe distance, in the flurry of information from different sources, lapses can occur.
For a short period on Friday night The Age did publish incorrect information that was subsequently corrected.
In these dramatic times, as information crystallises, the media and public move on quickly, trying to stay on top of the latest developments. But spare a thought, however fleeting, for the families of those unwittingly caught up in the drama.
How these two names came to be the focus of the Twittersphere and media for several hours on Friday night is a product of our times.
One of the men initially named as a suspect on Friday night was an Indian-American in his 20s who had been missing for more than a month. His devoted family had set up a Facebook page dedicated to his safe return, which was taken down just hours before the confrontation at MIT. A link was immediately made between that act and his rumoured role in the killing of four innocent people, including a police officer and a child.
Or how about Salah Eddin Barhoum, whose photo was plastered across the front page of the New York Post under the headline, "Bag men: Feds seek these two pictured at Boston Marathon." Now Salah, 17, fears going to school. All for being photographed wearing a backpack at a public event that ultimately turned to tragedy.
Four people are dead and hundreds more have been injured as a result of the unthinkable actions of the alleged suspects. For now, the focus of law enforcement and government officials must remain on finding Dzhokhar Tsarnaev, and then restoring a sense of normality to the city of Boston.
Still, as the world waits impatiently for official sources to release information that will feed the public's appetite without compromising the investigation, unofficial sources will inevitably fill the vacuum with misinformation, distortions and half-truths. Much of it is well-intentioned, motivated by mankind's search for answers in times of tragedy. But sometimes not enough thought is given to the lasting impact it will have on innocent people's lives.
Melissa Singer is deputy news director of The Age.
Melissa Singer
Melissa Singer is National Fashion Editor of The Sydney Morning Herald and The Age.


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«Инспектор Граудс» () — латвийский комедийно-детективный телесериал, премьера которого состоялась на телеканале LNT 15 сентября 2002 года. В России был переведен на русский язык и издан в формате VHS ЗАО «МостВидеоФильм» в 2003 году. Транслировался на телеканалах России и Украины.

Сюжет
Действие сериала происходит вокруг инспектора криминальной полиции Вентспилса Эдгарса Граудса и его четвероногого друга и коллеги — немецкой овчарки Арчи (Арчибальда), которого Граудс спас из реки, куда выкинул собаку её предыдущий хозяин. Хотя сериал повествует о жизни и работе полицейских, здесь нет кровавых разборок, убийств и жестокости — это сатирический, ироничный телесериал, а преступники в нём — чудаки, городские сумасшедшие и неудачники, действия которых вызывают только смех и улыбку.

Производство
Изначально телесериал был задуман как 16-серийный, но было снято только 6 серий. В съёмках было задействовано две собаки — сука по кличке Сэнди и кобель по кличке Рэмбо. Сэнди была обучена Национальным кинологическим центром и снималась в экшн-сценах, а Рэмбо — в «сценах дружбы», когда надо было показать обаяние.

В ролях
 Андрис Кейш — в роли Эдгарса Граудса
 Улдис Норенбергс — в роли Ольгертса Балонскиса
 Зане Валицка — в роли Катрины Плуме
 Улдис Анже — в роли Илмарса Брокса
 Юрис Рийниекс — в роли Екабса Зиле
 Янис Рейнис — в роли Болеслава Ципскиса
 Байба Брока — в роли Бируты
 Имантс Страдс — в роли наркодилера

Примечания

Ссылки
 Inspektors Grauds — IMDB

Телесериалы о собаках
Телесериалы Латвии
Комедийные телесериалы
Детективные телесериалы

redpajama_set_name: RedPajamaWikipedia


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Paranormal & Conspiracies
Proof of a secret society in the U.S.?
conspiracy government secret society
Real interesting stuff. Oh I like how they blame a "glitch" for losing all the rest of the texts. A "glitch" that's right. They have used this excuse before as well. With all these "glitches" you think our government should have top of the line equipment wouldn't you say? But this also speaks of a secret society.
House Oversight Committee Chairman Rep. Trey Gowdy (R-S.C.) on Monday raised concerns that the two FBI agents who privately exchanged text messages disparaging President Trump mentioned a "secret society" shortly after the Republican candidate won the election.
Gowdy joins a chorus of Republicans who are upset over texts between FBI agent Peter Strzok and FBI lawyer Lisa Page, with some claiming they serve as proof of FBI bias against Trump in the probes into Russian election meddling, as well as into Hillary Clinton's use of a private email server as secretary of State.
Strzok, who spoke in openly derisive terms about Trump, served on both investigations before being removed by the Russia special counsel.
"[T]he day after the election...there is a text exchange between these two FBI agents, these supposed to be fact-centric FBI agents saying, 'Perhaps this is the first meeting of the secret society,'" Gowdy said on Fox News' "The Story with Martha MacCallum."
"So I'm going to want to know what secret society you are talking about, because you're supposed to be investigating objectively the person who just won the Electoral College," he continued.
Gowdy also pointing to his concern about their mention of an "insurance policy" in their back-and-forth during the spring of 2016, a remark that has captured Republicans' attention.
Apparently there is talk about this group, they are called "The 7th Floor Group".
You can read it here for yourself, go to page #56.
https://vault.fbi.gov/hillary-r.-clinton/Hillary R. Clinton Part 04 of 17/view
Davidc
I don't know if I trust ABC News not to tamper with things. They could potentially blunt damming sections.
Ya is ABC Right or Left?
They are owned and edited by the CIA just like the rest of them. (Operation Mockingbird)


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The Super Bowl vs. The World Cup of Soccer
I was in a conversation yesterday about the pro sports teams in the city where I live - Toronto, Canada. At the time I didn't realize that a talk about sports could lead to business value add.
Toronto has a very profitable NHL Team, the Maple Leafs; an NBA franchise - the Raptors; and an MLB Team, the Blue Jays. The discussion was about the high cost of going to games, and that the business of sports is in decline (other than for the Maples Leafs and the New York Yankees).
I think that you don't have to look far to prove that sports is alive and well. For example, there are two mega sports events this year. One's happening this weekend - the Super Bowl. The World Cup of Soccer, takes place later in the year. Hundreds of millions of people worldwide will watch both.
What's more interesting from a business point of view is the impact the events make in the cities and countries where they're held. For example, according to the Detroit Free Press, the NFL says that this weekend's Super Bowl will make a $300 Million economic impact to the local economy. It's expected that the World Cup in Germany will bring £300 million or about $530 Million.
Based upon top line revenue it would seem that the World Cup has the Super Bowl beaten. But hold on a minute....Germany invested roughly $1 Billion to build and upgrade facilities to host the tournament. Meaning they're about $470 Million dollars in the red from the start. By the way, this will be true of every city hoping to host such events. Much like theOlympicss, the World Cup has to be financed by a country versus a syndicate of corporations.
The NFL doesn't have the hurdle of compelling the investment of billions of dollars for venues. This is why the Super Bowl is the superior event from a businessperspectivee....low cost of operating, no need for large scale investments plus it's easily transportable to different cities each year. This is why NFL Football is one of the most successful sports worldwide.
Earlier in the week I asked - Where are the Turnaround Products? In that article I wrote that I couldn't find many superstar products (other than iPod or Blackberry.) I realize now that there are superstar products in the one domain that's highly populated with "superstar individuals" - sports and in particular the NFL.
I'm writing about sports on a website dedicated to Business and Technology because there's a lesson here for anyone in business. The lesson relates to an organization's business model. According to Wikipedia a "Business model is the mechanism by which a business intends to generate revenue and profits."
Is your company's business model set up like the World Cup of Soccer or is like the Super Bowl?
Related Links: Business
Posted by davdan at Friday, February 03, 2006
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Relativity Space Gets a Huge Investment to Take on SpaceX With Reusable Rockets
Frontier Adventure
They say imitation is the sincerest form of flattery, and that competition is a great way to foster progress and innovation. If these truisms are to be believed, then the NewSpace industry is destined to benefit from the presence of Relativity Space, a commercial space company based in Los Angeles. At the same time, SpaceX founder Elon Musk should be flattered that Tim Ellis and Jordan Noone (founders of Relativity Space) are following his example.
Roughly six years ago, Ellis and Noone founded Relativity for the purpose of using new technologies to disrupt the aerospace industry. Earlier this week (Tuesday, June 8th), the company announced that it had raised an additional $650 million in private capital. This money will go towards the development of rockets that are entirely 3D-printed and fully reusable, as well as the creation of a new class of heavy launch vehicles known as the "Terran-R."
Years back, Ellis indicated that he and co-founder Noone were both inspired by Elon Musk and SpaceX's achievements in space. At the time, Musk had proven that his company could retrieve and reuse their Falcon 9's first stage boosters and that the commercial space industry could handle everything from launching payloads to orbit to sending resupply missions to the International Space Station (ISS).
However, Ellis and Noone were concerned that when it came to his long-term ambitions (i.e., building a self-sustaining city on Mars), there was a certain lack of planning. Similarly, they felt that the space industry was still reliant on labor-intensive practices that were rapidly growing obsolete with the introduction of additive manufacturing (3D printing). As Ellis explained recently to Ars Technica:
"In every SpaceX animation, we saw a fade into black right when people walked out of the rocket on Mars. So what was clear [is] that there needed to be some other company building humanity's industrial base on Mars. Replicating the infrastructure for a million people that live on Mars is a massive undertaking, and I think a lot of people need to work on it."
As aerospace engineers, Ellis and Noone were both intimately acquainted with the NewSpace industry. The two even worked for Blue Origin and SpaceX before founding Relativity Space, and much of their concerns arose from the practices they witnessed firsthand. Essentially, it came down to the inefficient way in which rockets were being produced, which was inconsistent with the companies' vision of reducing costs and making space more accessible.
This led to their decision to launch their own commercial space company that would fuse 3D printing, sensor and analytics-driven machine learning, and autonomous robots to create the structure and engines of their rockets. This, they hoped, would lead to a tenfold increase in production speed, a hundredfold decrease in the number of parts needed, a simplified and optimized supply chain, and a more rapid design and iteration process.
Optimized Production
At the center of their production efforts is their Factory of the Future, which relies on the Stargate – the world's largest metal 3D printing system – to build all of their hardware. This includes the Aeon 1 rocket engine, which relies on a combination of liquid natural gas (LNG) and liquid oxygen (LOX) and can generate 69,000 Newtons (N, or 15,500 pounds-force) at sea level and 113,000 N (25,400 pounds-force) in the vacuum of space.
The same method is used to create their rocket fleet, which includes the two-stage Terran 1, the world's first 3D printed rocket. This first stage relies on nine Aeon 1 engines, the second relies on a single Aeon VAC, and the entire launch system is capable of sending a maximum payload of 1,250 kg (2,760 lbs) to Low Earth Orbit (LEO), and 700 to 900 kg (1,500 – 2,000 lbs) to Sun-Synchronous Orbit (SSO).
Then there's the Terran R, the world's first 3D printed rocket that is fully reusable – engines, first stage, second stage, and payload fairing – which relies on seven Aeon R (LNG/LOX) engines for its first stage and one Aeon VAC for its second. This rocket is designed to compete with the Falcon 9 and will be capable of launching over 20,000 kg (44,000 lbs) to LEO, with a maiden launch from Cape Canaveral targeted for 2024.
These rockets and engines are printed from a propriety alloy using a process known as selective laser sintering and can build an entire rocket in just 60 days (and using less than 100 parts). This stands in contrast to the time-honored method of using traditional tooling to manufacture the various components, then relying on a hands-on process to assemble the thousands of parts together.
https://www.mansbrand.com/finally-new-pictures-of-ganymede-thanks-to-juno/
The Best Guide to Backpacking the Zion Narrows
Finally! New Pictures of Ganymede, Thanks to Juno
On December 25th, 2021, after many years of waiting, the James Webb Space Telescope (JWST) finally launched to space. In the sixth-month period that followed, this next-generation observatory unfurled its Sunshield, deployed its primary and secondary mirrors, aligned its mirror segments, and flew to its current position at the Earth-Sun Lagrange 2 (L2) Point. On July 12th, 2022, the first images were released and presented the most-detailed views of the Universe. Shortly thereafter, NASA released an image of the most distant galaxy ever observed (which existed just 300 million years after the Big Bang).
According to a new study by an international team of scientists, the JWST will allow astronomers to obtain accurate mass measurements of early galaxies. Using data from James Webb's Near-Infrared Camera (NIRCam), which was provided through the GLASS-JWST-Early Release Science (GLASS-ERT) program, the team obtained mass estimates from some of the distant galaxies that were many times more accurate than previous measurements. Their findings illustrate how Webb will revolutionize our understanding of how the earliest galaxies in the Universe grew and evolved.
The research team (led by Paola Santini of the Astronomical Observatory of Rome) included members from the Instituto Nationale di Astrophysica (INAF) in Italy, the ASTRO 3D collaboration (Australia), the National Astronomical Research Institute of Thailand (ARIT), the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), the Cosmic Dawn Center (DAWN), the Niels Bohr Institute, The Carnegie Institution for Science, the Infrared Processing and Analysis Center at Caltech, and universities and institutes in the U.S., Europe, Australia, and Asia.
As they indicate in their study, stellar mass is one of the most important physical properties (if not the most) for understanding galaxy formation and evolution. It measures the total amount of stars in a galaxy, which are constantly being added through the conversion of gas and dust into new stars. Therefore, it is the most direct means of tracing a galaxy's growth. By comparing observations of the oldest galaxies in the Universe (those more than 13 billion light years away), astronomers can study how galaxies evolved.
Unfortunately, obtaining accurate measurements of these early galaxies has been an ongoing problem for astronomers. Typically, astronomers will conduct mass-to-light (M/L) ratio measurements – where the light produced by a galaxy is used to estimate the total mass of stars within it – rather than computing the stellar masses on a source-by-source base. To date, studies conducted by Hubble of the most distant galaxies – like GN-z11, which formed about 13.5 billion years ago – were limited to the Ultraviolet (UV) spectrum.
This is because the light from these ancient galaxies experiences significant redshift by the time it reaches us. This means that as the light travels through spacetime, its wavelength is lengthened due to the expansion of the cosmos, effectively shifting it towards the red end of the spectrum. For galaxies whose redshift value (z) is seven or higher – at a distance of 13.46 light-years or more – much of the light will be shifted to the point where it is only visible in the infrared part of the spectrum. As Santini explained to Universe Today via email:
"The bulk of the stars in galaxies, those that mostly contribute to its stellar mass, emit at optical-near infrared (NIR) wavelengths… [B]y the time the light takes to travels from a distant galaxy to our telescopes, the light emitted by its stars is no more in the optical regime. E.g., for a z=7 galaxy, the light originally emitted at 0.6 micron, reaches our telescope with a wavelength of 4.8 micron. The higher the redshift (i.e. the more distant the galaxy), the stronger is this effect."
"This implies that we need infrared detectors to measure galaxy stellar masses (the light emitted by the bulk of their stars is out of reach of the Hubble Space Telescope). The only IR telescope we had before the advent of JWST was Spitzer Space Telescope, dismissed a few years ago. However, its 85 cm mirror was not comparable with the 6.5 m mirror of JWST. Most of the distant galaxies were out of reach of Spitzer too: due to its limited sensitivity and angular resolution, they were not detected (or affected by high levels of noise) on its images.
https://www.mansbrand.com/a-black-hole-can-tear-a-neutron-star-apart-in-less-than-2-seconds/
Almost seven years ago (September 14th, 2015), researchers at the Laser Interferometer Gravitational-wave Observatory (LIGO) detected gravitational waves (GWs) for the first time. Their results were shared with the world six months later and earned the discovery team the Noble Prize in Physics the following year. Since then, a total of 90 signals have been observed that were created by binary systems of two black holes, two neutron stars, or one of each. This latter scenario presents some very interesting opportunities for astronomers.
If a merger involves a black hole and neutron star, the event will produce GWs and a serious light display! Using data collected from the three black hole-neutron star mergers we've detected so far, a team of astrophysicists from Japan and Germany was able to model the complete process of the collision of a black hole with a neutron star, which included everything from the final orbits of the binary to the merger and post-merger phase. Their results could help inform future surveys that are sensitive enough to study mergers and GW events in much greater detail.
The research team was led by Kota Hayashi, a researcher with Kyoto University's Yukawa Institute for Theoretical Physics (YITP). He was joined by multiple colleagues from YITP and Toho University in Japan and the Albert Einstein Institute at the Max Planck Institute for Gravitational Physics (MPIGP) in Postdam, Germany. The paper that describes their findings was led by YITP Prof. Koto Hayashi and recently appeared in the scientific journal Physical Review D.
The mergers of compact objects discovered so far by LIGO and Virgo (in O1, O2, and O3a). Credit: LIGO Virgo Collaboration / Frank Elavsky, Aaron Geller / Northwestern
To recap, GWs are mysterious ripples in spacetime originally predicted by Einstein's General Theory of Relativity. They are created whenever massive objects merge and create tidal disruptions to the very fabric of the Universe, which can be detected thousands of light-years away. To date, only three mergers have been observed involving a binary system consisting of a black hole and a neutron star. During one of these – GW170817, detected on August 17th, 2017 – astronomers detected an electromagnetic counterpart to the GWs it produced.
In the coming years, telescopes and interferometers of greater sensitivity are expected to see much more from these events. Based on the mechanics involved, scientists anticipate that black hole-neutron star mergers will include matter ejected from the system and a tremendous release of radiation (which might include short gamma-ray bursts). For their study, the team modeled what black hole-neutron star mergers would look like to test these predictions.
They selected two different model systems consisting of a rotating black hole and a neutron star, with the black hole set at 5.4 and 8.1 solar masses and the neutron star at 1.35 solar masses. These parameters were selected so that the neutron star was likely to be torn apart by tidal forces. The merger process was simulated using the computer cluster "Sakura" at the MPIGP's Department of Computational Relativistic Astrophysics. In an MPIGP press release, Department director and co-author Masaru Shibata explained:
"We get insights into a process that lasts one to two seconds – that sounds short, but in fact a lot happens during that time: from the final orbits and the disruption of the neutron star by the tidal forces, the ejection of matter, to the formation of an accretion disk around the nascent black hole, and further ejection of matter in a jet. This high-energy jet is probably also a reason for short gamma-ray bursts, whose origin is still mysterious. The simulation results also indicate that the ejected matter should synthesize heavy elements such as gold and platinum."
The team also shared the details of their simulation in an animation (shown above) via the Max Planck Institute for Gravitational Physics' Youtube Channel. On the left side, the simulation shows the density profile as blue and green contours, the magnetic field lines that penetrate the black hole are shown as pink curves, and the matter ejected from the system as cloudy white
https://www.mansbrand.com/lava-tubes-on-the-moon-maintain-comfortable-room-temperatures-inside/
Searching for a comfortable place to set up a research station on the Moon? Look no further than the interior parts of lunar pits and caves. While lack of air will be an issue, new research indicates these underground sanctuaries have steady temperatures that hover around 17 Celsius, or 63 Fahrenheit, even though the Moon's surface heats up to about 127 C (260 F) during the day and cool to minus 173 C (minus 280 F) at night.
Lunar pits, or lava tubes were discovered in 2009 by the Lunar Reconnaissance Obiter and Japan's Kaguya spacecraft. These are deep holes on the moon that could open into vast underground tunnels. They likely could serve as a safe shielding from cosmic rays, solar radiation and micrometeorites for future human lunar explorers. But now we know they could provide thermally stable sites for lunar exploration.
These long, winding lava tubes are like structures we have on Earth. They are created when the top of a stream of molten rock solidifies and the lava inside drains away, leaving a hollow tube of rock. For years before their existence was confirmed, scientists thought there were hints that the Moon had lava tubes based on observations of long, winding depressions carved into the lunar surface by the flow of lava, called sinuous rilles.
Thurston Lava Tube on the Big Island of Hawaii. Credit: P. Mouginis-Mark, LPI
So far, about 200 lunar pits have been found and at least 16 of these are probably collapsed lava tubes, with the potential for 'livable' space, said Tyler Horvath, a UCLA doctoral student in planetary science, who led the new research. Two of the most prominent pits have visible overhangs that clearly lead to some sort of cave or void, and there is strong evidence that another's overhang may also lead to a large cave.
Horvath processed images from the Diviner Lunar Radiometer Experiment — a thermal camera and one of six instruments on LRO — to find out if the temperature within the pits diverged from those on the surface. Diviner is designed to measure surface temperatures on the Moon, and Horvath's team had to focus in on extremely small areas to get their data.
They focused on a pit found in the Sea of Tranquility (Mare Tranquillitatis). This image, below, was taken as the Sun was almost straight overhead, illuminating the region. By comparing this image with previous images that have different lighting, scientists can estimate the depth of the pit. They believe it to be over 100 meters.
This is a spectacular high-Sun view of the Mare Tranquillitatis pit crater, revealing the overhang and deep, dark pit. This image from LRO's Narrow Angle Camera is 400 meters (1,312 feet) wide, north is up.
Credits: NASA/Goddard/Arizona State University
The researchers used computer modeling to analyze the thermal properties of the rock and lunar dust and to chart the pit's temperatures over a period of time. Their research, recently published in the journal Geophysical Research Letters, revealed that temperatures within the permanently shadowed reaches of the pit fluctuate only slightly throughout the lunar day, remaining at around 17 C (63 F). If a cave extends from the bottom of the pit, as images taken by the Lunar Reconnaissance Orbiter Camera suggest, it too would have this relatively comfortable temperature. The researchers think the overhang is responsible for the steady temperature, limiting how hot things get during the day and preventing heat from radiating away at night.
However, if this particular pit was to be used as a habitat or research station, there would likely be a heat problem just inside the pit.
https://www.mansbrand.com/a-fast-moving-star-is-colliding-with-interstellar-gas-creating-a-spectacular-bow-shock/