CULTURAL QA 10-2023-19A All the BELOW QA are from Quora digest to me on 19-10- 2023.
Quora answers need not be 100% correct answers .Compiled and posted byR. Gopala krishnan, on 19-10-2023 Q1 Doeslight travel forever or does it eventually fade? A1 Tafer, PHD in Power scaling &Debunking, Hogwarts School of Witchcraft and Wizardry (fictional school)(Graduated 2020)9mo Light is a type of electromagnetic radiation thattravels through space at a constant speedof about 299,792,458 meters per second (186,282 miles per second). Light is able to travel througha vacuum, which means that it does not need a medium (such as air orwater) to propagate. Light does notfade over time, but it can be absorbed, scattered, or otherwiseabsorbed by matter, which can reduce its intensity or change its direction oftravel. For example,light from a star that is billions of light-years away from Earth can beweakened by the dust and gas in interstellar space, and it can also be affectedby the gravitational fields of celestial objects such as planets and galaxies. However, even if light is absorbed or scattered, it does not disappear. Instead,it is transformed into other forms of energy, such as heat or kinetic energy.In this sense, light can be said to be "eternal" in the sense that it can never be completely destroyed, but it can change form and betransformed into other types of energy. Q2 Whydid France want to ban domestic flights in favor of a high speed train service? A2 Nicholas Stone,Life long interest intrains.13h The French government banned some domestic flighttravel, for climate change and rail policy reasons. The EU’s EuropeanCommission approved the ban and French government then signed this into the country's Climate Law on23 May 2023. The ban onlyapplies to three routes. Specifically Paris' Orly airport to Bordeaux, Lyon andNantes. Paris Charlesde Gaulle still offer services to these routes for connecting passengers. The ban also reflect France’s excellent domesticelectric high speed train service. Most French cities are less than 3 hoursfrom Paris by train. While Lille, LeMans and Rheims are less than 90 minutes by train from Paris. In September2023, I travelled domestically in France - between Bordeaux and Paris. This isa distance of 550 km by rail. The journey time on the famous TGV passengertrain was just 2 hrs 05 mins. This domestic journey was neither possible byplane, nor even recommended. Q3 Howlong does it take for Earth to go around our sun once? What is that called? A3 Jeff Lewis, Studied at University ofMaryland, College Park Tue Okay QuoraPrompt Generator, you've drawn me in with another question that's moreinteresting than most people realize. The time ittakes for the Earth to go around the Sun once is known as a sidereal year, which isdifferent from a calendar year (or more accurately, a tropical year). And it's not just because calendar years have to use whole days – evenwith leap years, sidereal years and calendar years drift away from each other. The issuecomes down to what we want a year to represent. It seems that society has settled on wanting ayear to represent the cycle of the seasons. We should allremember from grade school that the seasons are caused by the tilt of theEarth's axis, but this tilt wobbles, or'precesses'. While the Earth's axis is currently aimed more or less at theNorth Star, because of this wobble, in about 13,000 years, it will be aimedcloser to Vega. So, if we measured years as the time ittakes the Earth to go around the Sun, then 13,000 years from now, the seasonswould be switched. Januaryin the northern hemisphere would be warm, while July would be cold, andsolstices and equinoxes would all be 6 months out of phase compared to wherethey are now. So, to keep a year representing the cycleof the seasons, we use a slightly different definition of a year – the time for the Sun toreturn to the same relative position in the sky (i.e. vernal equinox to vernalequinox, or summer solstice to summer solstice). This is technically known as a tropical year,and is around 20 minutes shorter than a sidereal year. Usingtropical years means that 13,000 year from now, the summer solstice will stilltake place in June, but the Earth will be on the opposite side of the Sun whenit happens. ABOVE SOURCE: As Earth wobbles due toprecession, do the seasons change in regard to the months (i.e., 13,000 yearsfrom now, will June be winter for the Northern Hemisphere and December summer)?| Astronomy.com This is also the reason why the signs of theZodiac are drifting. While 13,000years is a pretty long time, it's still short enough to be noticed in the timeframe of civilization. Since the signs of the Zodiac were based on theconstellations the Sun was passing through at the time, and that it's beenaround 4,000 years ago since those signs were first developed, that means thatthe difference between sidereal and tropical years means the constellationshave drifted roughly 31% of the way (4/13) to their opposite relativelocations. Or another way to look at it, 4/13 is really close to 4/12, whichmeans the signs have shifted just about 4 places by now. So, to answer the question with actualvalues, the time it takes the Earth to go around the Sun, a sidereal year, is365 days 6 hours 9 minutes 10 seconds, while the cycle of the seasons, atropical year, is 365 days 5 hours 48 minutes 46 seconds. A calendar year, pretty obviously, is nearlyalways either 365 days or 366 days depending on whether or not it's a leap year(with the occasional leap second), with the timing of leap years designed tokeep the calendar years in sync with the seasons. Q4 Whatare some cool facts about the Universe? A4 Ariel, Studies Psychology (Expected2025)3y When you look into the night sky, you are lookingback in time Many of the atoms you're made of, fromthe calcium in your bones to the iron in your blood, were brewed up in theheart of an exploding star billions of years ago. And back inthe days before digital television, if you tuned your TV between stations, asmall percentage of the static you would see would actually be the afterglow ofthe Big Bang. Outer space is silent. Eerily silent. That'sbecause sound waves need some sort of medium to travel through. And space is avacuum. A dark, silent vacuum. The sun makes up 99.86% of the mass of the solarsystem. It's so big that you could squeeze1.3 million Earths inside of it. There mightbe as many as three sextillion stars in the universe. That's 3 followed by 23zeros, or 300,000,000,000,000,000,000,000. That's more than all of the grainsof sand on Earth. Ordinary, observable matter (like stars andplanets) makes up a measly 5% of the universe.The other 95% universe is made up of invisible dark energy (68%) and darkmatter (27%). That means there's 95% of the universe that we don't know aboutyet. It takes 225million years for our Sun to travel round the galaxy Our solar system’s biggest mountain is on Mars The human brainis the most complex object in the known universe We are all made of stardust Q5 Whatare some interesting facts about the Sahara desert? A5 Gary Meaney, passionate fan of allthings animal2y My note- Lengthy answer. Very informative andinteresting answer. 8 page answer. Please read at spare time. The Saharais unimaginably vast; spanning some 9 million square kilometres, it’s the world’s largest desertoutside those of the polar regions. Thus, as you would expect, there’s an awfullot of interesting stuff going on inside it. For this answer I’ve picked onlythe most fascinating tidbits I could find on this region. Despite its (deserved) reputation as a scorchingwasteland, it does occasionally snow in the Sahara.Three instances of significant snowfall have been recorded here, all inAlgeria, and in all cases the snow melted within hours of it falling. The last time it happened wasJanuary of 2018. In some parts of the Sahara Desert, especiallyTunisia, desert roses form. These arebeautiful crystals of gypsum, encrusted in sand, which are created by theevaporation of shallow water bodies. It’s easy to see how they get their name. In Mauritaniayou can find an immense circular rock formation known as the Richat Structure,or the Eye of the Sahara. It measures fortykilometres in diameter, and was originally thought to be an impact crater, butis now understood to be an eroded dome of volcanic rock. About 14,500years ago, an era called the African Humid Period began,lasting up until ~6,000 years ago. During this time, the monsoon of WestAfrica became stronger, and the Saharan region saw a marked increase inrainfall. Thedesert gave way to lush savannah, leading to a Green Sahara. Lake Chad is currently the largest body of water inthe Sahara, but it is a shadow of its formerself. While the region was green, Lake Chad was Lake MegaChad, over 700 timesits modern size! In fact, it was the world’s largest lake, by far, at more thana million square kilometres in area. The Sahara Desert contains moreprehistoric rock art than perhaps any other part of the world.These ancient paintings date back as far as 12,000 years ago, and depict everythingfrom warfare and farming to people swimming and now-extinct local wildlife. They are an invaluablewindow into the lush, rainy past of this now-bleak desert. In EasternMorocco, there is an incredibly rich fossil site - the Kem Kem Beds -from around 95 million years ago. It shows that this part of the Sahara was once a marshy place which wasthe abode of some of the largest carnivorous dinosaurs of all time,30-ton sauropods, giant crocodiles, sawfish bigger than minivans, and muchmore. The desert’s Saharan silver ants arespectacularly well-adapted to the extreme heat.Their beautiful silvery hair reflects sunlight, and they have special proteinswhich allow them to withstand up to 53 degrees Celsius! Even still, they canonly spend 10 minutes per day in the sun, so they have to be speedy - in fact,for their size they are the third-fastest organisms on Earth. (That paragraph was criminally short for anoverview of these amazing ants, I’ll have to do them justice in a full answersome day…) The Sahara is home to a fascinating plant calledAnastatica hierochuntica, also known as therose of Jericho. When the dry season begins, it shrivels up and becomes fullydesiccated, detaching from the ground and blowing away in the wind. Yet, uponcontact with moisture in the following wet season, it “resurrects” itself,regaining its former vitality. In Chad, you canfind Guelta d’Archei, a beautiful secluded oasis in a deep sandstone gorge.Every day, it is used by local herders to quench the thirst of thousandsof camels, which have stained the waters black with their dung. Theoasis is the only known remaining colony of West African crocodiles in theSahara Desert, too. In 1993,electrician Emile Leray was travelling in the desert of Morocco when his carallegedly hit a rock and had its front axle destroyed. He dismantled the wreck,and used the parts to build a fully functioning motorcycle, which he dubbed his“Steel Camel” and rode to civilization. (It’s worthmentioning that, while this is nevertheless really cool, it’s unlikely that itwas a daring tale of survival as is often claimed. What’s much more probable isthat Leray went to the Sahara with the explicit intention of building amotorbike out of his Citroen there.) The hottest known part of the Sahara Desert is BouBernous, a very small and isolated town in westernAlgeria. Its average temperature over the course of a day was oncerecorded at a blistering 47 degrees Celsius, the highest suchmeasurement anywhere on Earth! My note- Thelowest temperature recorded in Chennai is 15.8 °C (60.4 °F) and highest45 °C (113 °F)(30 May 2003). The average annualrainfall is about 1,400 mm (55 in). The city gets most of its seasonal rainfallfrom the north-east monsoon winds, from mid-September to mid-December. (Googlesearch result) If you look at a satellite map of Libya, you mightnotice an abrupt little black dot. That is Waw an Namus, a verdant oasis inside a volcano,famous for its black tephra (volcanic gravel, basically). It is rich in bird-life, unlike the surroundingwasteland. The AncientRomans made several military explorations deep into the Sahara,even venturing into sub-Saharan Africa. One expedition party, for example,arrived at Lake Chad, which they called the “lake of hippopotamuses”. Theystationed a small garrison here. In Mali’s Dogon region,in the southern extreme of the Sahara, there is a steep cliff known as theBandiagara Escarpment. Here, thelocal people build spectacular villages of mud huts which hug the sandstonecliffside. The Mauritanian Railway is a rail route on whichsome of the world’s longest trains traverse. These trains can be up to threegoddamn kilometres long, and weigh tens of thousands of tonnes! They carry ironore and occasionally passengers. My note- Google search result-Since the closure of the Choum Tunnel, a 5km (3.1 mi) section of the railway cuts through the Polisario Front-controlledpart of the Western Sahara (21.354867°N 13.012644°W). In Tunisia, there is a unique desert villagecalled Matmata. Here, some local Berbers dwell in underground houses,formed around one or more large pits, perfect for shielding oneself from thescorching Saharan sun. Thetown was the main filming location of Tatooine in the original Star Wars film. One of Egypt’s UNESCO World Heritage Sites is Wadi ElHitan, or the Valley of the Whales. It is infact a paleontological dig site, where exceptional fossils of the ancient whaleBasilosaurus have been uncovered. Remains of sharks, sea cows, turtles and even the first ever pelican havealso been found there, showing the sands were once a shallow sea. Morocco boasts the title of having the world’s largestconcentrated solar power plant, theOuarzazate Solar Power Station. Its construction began in 2013, and when it isfinished it will produce an estimated 582 megawatts of energy. The project hascost around 2.5 billion dollars. Though not nearly as famous for the structures asEgypt is, Sudan is home to over 350 pyramids -more than twice as many as the former nation has. These were built by theNubian people, who were then known as the Kingdom of Kush, starting at around800 BC. When you think about Saharan scenery, you probablyimagine featureless dune fields and rocky plains, but the Hoggar Mountains ofAlgeria feature many dramatic landscapes.These highlands are volcanic in origin, and some of their peaks are nearly 3kilometres high. In the desert of Niger, you can find the world’stallest mud-brick building, the Mosque of Agadez.It was built way back in 1515, and has gone practically unchanged since then. In Morocco every year, the Marathon des Sablesis held - arguably the world’s most gruelling and challenging footrace.At 251 km in length, the course is six times longer than a standard marathon,and takes nearly a week to complete. Due to COVID-19, the racehasn’t been held since 2019. There is a7,000 square kilometre lake in the Tunisian Sahara called Chott el Djerid which- in summer - becomes the desert’s largest salt pan. Dueto evaporation, a crust of salt builds up over the water, thick enough to drivea car over. When wintercomes, it returns to its watery state. On average, 182 million tonnes of Saharan dustare blown west over the Atlantic Ocean each year. Ofthat, 28.8 million tonnes settle in the Amazon Rainforest of South America.This seemingly plays a crucialrole in the jungle’s biodiversity, as the dust carries vital minerals forfertility such as phosphorus. Some of thatdust also ends up in Cape Verde, an archipelago off the west coast of theSahara, and acculumates in the Viana Desert. This small field of sand dunes could be considered anextension of the Sahara Desert found way out in the Atlantic Ocean. Egypt is home toboth a Black Desert and a White Desert.The former is a volcanic area full of mounds of basalt, in which dinosaurremains have been excavated. The latter is famous for its chalk rocks, whichhave been eroded into exquisite shapes. So, I’ll leave it that for today.At first glance, the Sahara seems pretty empty, but upontaking a much closer look I’ve realized that I couldn’t possibly fit all of itsinteresting features in a digestible answer. I hope you enjoyed the onesthat I selected. As an aside, I know the phrase “Sahara Desert” istautological, as the word Sahara itself derives from the Arabic word for desert.However, I have used the phrase in this answer, mainly to mix up the wordchoice a bit. A bit ironic that I ended up using a repetitive name to avoidbeing repetitive, but anyway… -- You received this message because you are subscribed to the Google Groups "Thatha_Patty" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/thatha_patty/1261662519.639696.1697725180893%40mail.yahoo.com.
