as it were, by 15 super stomach jets, a move that could revive high speed commercial air travel, the jets make a boom supersonic says you can fly up twice to speed of today's leading aircraft. and that would cut travel time from london to new york to 3 and a half hours. united airlines pants launch a service in 2029. the high speed market failed to recover after the ephron concord crash 21 years ago. that killed a 113 people. ah, for a quick check of the headlines here on 0, thousands of molly owns have gathered in the capital by marco to show support for the military june to it's the 1st rally since colonel se negotiator sees power last month. nicholas hawk, or north america. what's interesting is that most molly and didn't come out in support of the military agenda and chose to stay home. and that's because in fact, since the military to into took power,

the security situation has gone from bad to worse just this week. we thought attacks from the acadia affiliate german thought in the law was the mean in the south of the country, not in the center in the north. we saw a tag on the us base just a few days ago, perhaps orchestrated by the storming state in the greater so hard to groups. there are gaining ground and gaining areas where the molly army are retreating and losing control in occupied east jerusalem. hundreds of people have held a marathon in solidarity with palestinian families facing, forced explosions. the run began and shut, draw, and didn't see why. it was scuffled between the projectors and is ready. soldiers, dozens of palestinians living in the 2 neighborhoods around the threat of losing their homes to israeli settlers. protectors were also held in nablus in the occupied west bank. israeli forces 5 to gas and rubber coated steel bullets. at least 20 people were injured that facebook has suspended. former us president

donald trump for 2 years. the social media company says trump was ban violating community standards. in connection with the capitol hill writes on january 6 from recently began his own blog page. but that was removed from his website earlier this week. witnesses in london that been giving testimony on alleged human rights abuses against china as we get muslims. the hearing is taking place of a 4 days and what's being called a people's tribunal. it's not backed by the british government and has no power to sanction china, but organize hope it'll spark and international movement to stop more abuses from taking place. and a vigil in hong kong, the victims of the 1989 gentlemen square massacre has been stopped by police. some people did gather that they were dispersed. the organizer of the vigil was arrested early on friday to activists have already been detained, including the organizer. so those are the headlines. the news continues here

on to 0 after science and the golden age that you've done watching life now. talk to al jazeera, we can, the army were attacking ringer, and now they're attacking everyone in me on my do you regret words like that? we listen. absolutely. nigeria with a woman precedent. it would be great. we meet with global news makers and talk about the stories that matter on our sierra. ah, understanding the universe from the office space is at the forefront of physics and astronomy research today. everything from white dwarf and red giant to neutron stars and black holes. but imagine trying to make sense of the cosmos before the telescope, even invented. well between the 9th and 14th centuries, stolen from the flemish world, consolidated and refined the astronomy of earlier civilizations. and came up with

ideas that have deeply influenced astronomy, right through to the present day onto masculinity. a british professor of physics born in back that. and i'll be taking a look at modern day, strong in the navigation, and exploring the contribution made to these fields by the scientists of the golden age. ah, [000:00:00;00] ah ah,

why word scholars of the stomach world. so interested in astronomy. one reason is for navigation. people have been using the sun and the stars to find their way around for thousands of years. i'm heading into the desert outside of dough, high baton, and i'm using the sap now to help me. so in a sense, i'm still looking to the sky to navigate well, now it's getting late and i think i'm really lost. i think i have to call someone to help me the id on it. it's a battery businessman embedded with a deep knowledge of the deserts and the better way of life. navigation has always been a crucial skill for the bed. doing so. ali, as a bedouin, how do you find your way around the desert so so accurately? there's 2 to tow during the day,

we know by the fun in the side or the side. if it's in the middle, sometime we get lost then and then i will go by a stops. you're familiar with. oh yeah. which is in the north. yes. it's always there and we have some, i don't know names like as hale joyce, these all star names and all arabic names. yeah. yes. and we know the direction by that this stuff bed when by, by the way, they have a very unusual sense of direction. it's in their d n a. when i'm driving walk and i know if you just stop me and somebody said all the way, it's not, it was just not immediately ah, thank you. in this one is navigation astronomy,

it was also important for the measurements of time. for example, the slamming calendar is a lunar calendar where the month determined by the phases of the moon. during the golden age, astronomy studied the movement of the moon to predict the calendar more accurately the 12 month making up the atlantic year, a shorter than the orbit of the sun. so slamming months and religious observances like ramadan move from year to year in the loan on the calendar is a short cut by 11 days and 333 years about it will. it's a cycle, for example, you know, the gregorio? yes. for example, if i start in forever, i'm about to start now in january, which is in the middle of the winter. yes. after the 33 years, it will come back again in january. ah,

i think these days even someone let me can pretend to be as knowledgeable about the night sky because i want to show you this app i have on my tablet. you see it shows wow. map. the night sky. yes, yes. let me see if i can see the north, the stock you so all you know that's north the yeah. i have to. yeah, that's it. i thought they call it the north star. well, that's another name for it, but it's it. see, i don't need to know that north i can hold that i. if i know the know wall star is there, then we know you know the direction that i should know my direction. ah, ah ah, the, this apple, my tablet allows me to scan the night sky and identify the stars and planets is the

modern day equivalent of the ancient starch are known in arabic as each. now in the early 9th century, the boss of keyless elma moon, the ruler of the powerful islam mac empire, was a man obsessed with scholarship and learning. and he commissioned a group of astronomers to produce a news age. now they already had the astronomical tables of the ancient greeks, but they were tasked with improving on them correcting errors and making more accurate measurements. they produced a new star chart. they became known as age and moved to hon, or the verified table. ah ah ah.

in a stumble, i'm standing on the very edge of europe. what i can look across to asia, on the other side of the buffer, the from the 7th century, the lemme empire and its people spread out to the rapier, to asia in the east all the way to spain, new york. ah, but the whole cost so much land, they had to be great navigators. throughout antiquity maps withdrawn by hand and relied on travelers account. for example, before the golden age, the greek astronomy ptolemy had compar lists of over 8000 coordinates, detailing the positions of oceans, landmarks and city. in the 9th century, the ruling kaylee for the fact that the moon commissioned a group of his scholars to make a new battle of the world and to improve on ptolemy data,

stumbles museum of the history of science and technology and islam doctor that left quinta and is a scholar of the ancient geography. together we're looking at element moon's map. this map dates back to the rain of moon and the 1st 3rd of the 9th century. the flourishing period of rhetoric is lemming science. and by that, i guess what was different about is that they wanted to improve on, on the greeks maps. absolutely. they measured the long get shoot and just shoot us back. and of course the, but that didn't even exist in the top. they had to, i guess, add all these new cities, mecca as well, mecca as well. so there were a lot of more precise caught in these oma moons, met for some very early years of age. here we have an example of a map, several centers later, the culmination of geography and in the slammer empire is

a map of the world. but it's not one that i recognize. i don't see any countries that they should. all rhetoric maps, how supports oriented. so africa was always on the top, the top, so if that, so this is upside down, it is up, so don't we can recognize it. that's better. okay, so now i see a ravia and the mediterranean. so what would new difference about this man? you can see the shape of the mediterranean and the short and precise even onto the shape of the caspian sea. and it was this map then of course led on to advance is the neuro absolute mental that with the importance of navigation. ah, so how did the math late because of the golden, a determined touch, the field measurement they use diverse cons frontier instrument called an extra

name. the come to the museum is flat, mac, all utter where among the many artifacts they have a wonderful collection of actually standing back almost a 1000 years. i'm hoping that one of their curators, dr. new con is going to tell me what's special about a couple of them in the lovely thing about esther leaves, nor is that before the invention of the telescope, these devices were incredibly important. how far back dash relieves go with a 1st story and say they go back to $300.00 b, c in greece, and the word aster lay comes from the arabic love, love exactly what we originally from the greek to grasp the stars. because actually what you have here is a handheld model of the sky. early yesterday, labor offered only a few functions. but during the golden age, astronomers developed more sophisticated astral apes. this one is very,

very elaborate. and it's multifunctional. it's in many ways with the, the computers of their day. and they basically served a number of purposes. you can use it to find the time of day or night. you could decide prayer time, you could navigate, you could measure the height, the building go distances. so that you can do all of that with this because of course these are all moving parts. it's possible to, to, to take it apart. yeah. and we can, we can, a single map of the stars would only be correct for one location on the earth. but these sophisticated aster leaves were designed to work in many places. a later aster date, such as the 17th century yesterday had a number of different place engraved on both sides. and each one could be used for a different city to tell the time to plot the motions of the stars or whatever it is that you needed us to live, to do wherever you were in the world. you'd use the half of the scar with all its

intricate markings and measurements to use an extra layer. you already needed a good working knowledge of astronomy. so here we have plates inside you then adjust this. see if you put the right place in position. yes, you take a measurement of, of a particular star or on, and then then you adjust the reach over the correct plate and that gives you a map of the sky where you are, the, me actually what helpful tools for astronomers in the golden age models going to have access to a vast array of instruments such as this, the level radio telescope in short rule bank in the u. k. during the golden age,

astronomers would come together from across the world to co operate. and that way of working is still imbedded in astronomy. today, the sun, them is working with this telescope, often collaborate with other telescopes and astronomers. internationally. unlike conventional telescope doesn't capture light through lens, but rather uses a mask that collects very weak radio signals from deacon's face, allowing us to mask the universe in ever greater detail. tim, because the level telescope is a radio telescope, it's seeing the sky in a way that we can see. yeah, i mean, it basically sees the invisible universe. i've got a picture here of what the level telescope sees. if we could see radio was, this is the way the sky would appear. that's how milky way galaxy, what we see in the picture is not the stars that we see with our eyes. it's the stuff between the stars. one of the really interesting things, i think if you look at planets arrived over stars, there's

a picture here of young star in our galaxy and cold h l t. how the stars of the center and then around it, there is a disc of gas and dosed for the interest thing. here are the dark circles. we think that they're formed by planets that have the deformed inside the disk. and as those planted circle around a sweet pop, the gas and the dust and the li behind these empty gaps. it's amazing, isn't it, that we're not talking about planet going around our own phone system. these a plan is going around distance of hundreds of light years away, and many, many thousands of these pies, many billions. in fact, in our mill q out. and you mentioned that image was taken by another telescope. this is part of a larger collaboration to get these sort of sharp views. we have to combine signals from many telescopes spread across the country and even across the planet itself. so this shows is all the locations of the various radio telescopes across europe, out into china, down into south africa. and we even linked these telescopes with

a russian spacecraft. that's all but in the week. so we end up making telescopes, the size of the planet, or even larger than that because they're all contributing their own data. so a single telescope will give you a blood view by working together with these telescopes, you know, in these countries, we all join forces to make this planet size telescope that shows the detail this idea of find this working collaboratively together, particularly in astronomy, is something that goes back a 1000 years to the golden age. it was impact. dad ran the 9th century when we 1st start to see astronomers working in groups to solve big problems. in astronomy, something that the greeks didn't do something the only really emerged in the golden age. and has survived so successfully to this day. ah, one of the most important exhibit trains of the golden age was called the moreover

observatory, built in 1259 in persia for the greater stone on the l. to see, when the mon goals invaded, they captured the mountain fault of allah moved well to see what. not only did he convince them, uncle, general hallmarkco, or hello con, to spare his life, he convinced him to build him a new observatory in return altos, who promised to provide the general with his astrological chart, so that he'd know what day to go to battle. the more of the observatory became the most important of its day, and a great hub international find to collaboration. ah, of course, was great about the morale, the observatory in astronomy. there isn't the observations they may, they didn't have telescopes, but it's the mathematical tricks they develop. that will be influential in astronomy, for centuries to come. and i wanted to show you something here. so this is a diagram for me to seize work. people like to see when they're looking at trying

to explain how the stars and planets moved. they were trying to develop the math to make it sensible. you know, they were using the greek model. yeah. which had gone incredibly complicated course . the greeks believed the central solar system in order to make the mathematical model fit the observations of the way in which the planets appear to move on the sky. they have for always ridiculously complicated features into the model. it got very, very messy circles within the circle of going around other circle. and that's, that's with to says genius comes in because this diagram the, to see couple simplified a lot of that for show you what's supposed to happen. you see this small circle going around the big one. if you trace a point on the perimeter, it's moving up and down in a straight line. and that turned out to be a very useful trick that simplified a lot of that complicated math. but what's really fascinating, compare this text with an arabic with this one is an identical one,

but written in latin and were fascinating. is the letters labeling the points follow the arabic alphabet, not the latin alphabet. so as if by gene does a b, g. clearly whoever to this knew about to work and the to the coupled with a manager, this was copernicus. so this is copernicus who came up with the idea though, rather than the earth being the central office of it was the some senator and all the plants including the earth, revolves around a revolt around it. and that's the picture that we have today. copernicus was and is regarded as the father of modern science because of this great revolution. i mean, it was so fascinating that this was built on the on to says id. yes. so it shows the continuity of science, copernicus owes this debt to these medieval astronomers from the golden age. incredible. ah islam itself, with

a significant reason behind many of the early explorations and discoveries in astronomy, during the golden age, there was a need to know the accurate time for prayer, the direction to face towards mecca, and the date of religious festival, according to the calendar. astronomical incidents, like the actually played a very important role. ah, ah, the huh. 0, one of the requirements of what to know which direction mecca was in order to face towards it during prayer. now, during the early days of the empire, it wasn't so large and this wasn't the problem. the scholars of the golden age very

proficient that map making. but as the empire grew and stretched from india in the east, all the way to spain under lucy, in the west, it was much more of an issue, because the scholars also knew that the earth wasn't flat. now, what does this matter? well, if you say a wisdom in corda, then facing towards mecca, if you just looked at the flap map, would involve pointing, roughly se on the globe is difference. if i attach this string one in to corda and the other to mecca, then you see the line actually takes you east to begin with and then curves down to the south east. so it's not at all obvious without understanding that the earth is a sphere. this meant that the stolen had to develop an area of mathematics called spiritual geometry, which was exceptionally advanced 4000 years ago. but to use this 3rd call geometry scholars 1st needed to know the size of the earth. the ancient greeks had

provided several estimates of this method was clever, but crude. it involved measuring the angle of the thumb at a particular time of day and then walking in a straight line in a particular direction and filled up the angle changed by one degree. all they then needed to do was calculate how far they need to walk, for the angle to change by 360 degrees. that would give them the circumference of the the early 9th century, a basset, keyless moon. wanted to improve on this estimate. so he commanded a group of astronomers to repeat it. however, the method involved them trudging through the desert for over a 100 kilometers a method that was prone to era. 200 years later, in the 11th century, the persian astronomer l bay rooney came up with a much easier and more accurate method of estimating the size of the earth. but it

did involve climbing a mountain that looked out over the horizon. rooney was a prolific scholar who even debated about whether the earth was moving. he explained how to work out the size of the earth in his book on the determination of the coordinates of cities. first, he measured the mountains height. elburn, he then had to climb to the top of the mountain and armed with an ester lake and a plum line, he then measured the angle of dip from the horizontal down to the distant horizon. now this was just half a degree, so he had to be incredibly precise. but armed with this information, he could then use a more clever geometry to calculate the circumference of the earth. let me show you . imagine this circle is the earth. and this

is they rooney's mountain now looking across horizontally, he measured the angle of dip. seuss the horizon this angle here. now if you draw 2 lines, one through to the sense of the earth from the mountain and the other from where the line touches the horizon, you end up with a right tangled triangle. now, they rooney knew that the angle he measured is the same as this angle inside the armed with these 2 pieces of information, the size of this angle and the height of the mountain. he was able to use geometry to work out the radius of the earth. multiplying this number by 2 pi gives him the complete circumference he got to within one percent of the accurate value we know today about 40000 kilometers, which is pretty remark. ah,

it's easy to think that astronomy went to sleep off the be great. i didn't wake up again and feel copernicus and the 15th century. but developments and astronomy continues in spain, the middle east and central asia throughout medieval times, through nasal sinus of europe who created modern astronomy were building on the work of people like l. bay rooney, and to see who in turn were building on the knowledge passed over to them from earlier civilization. today in the 21st century, international teams of scientists are still looking to start a mapping the cosmo using ever largest health. but we must remember that they owe a huge depth of gratitude to those a strong him as of the morocco observatory. ah, next time we cover how the scholars of the stomach world math and science. ah,

we delve into the equations of flights and discover how the mathematicians of the golden age laid the foundations of algebra. it's extraordinary that they might that step to the cubic equation the we see the role they played in the evolution of numbers themselves. everywhere today, we use this decimal system and we forget how difficult it was before it exists the . and we reveal how the legacy has led to the mathematics. behind the fastest car in the world is the longest spending record in history. and up to this point, nobody has broken it. that's about to change with a new call to get a lot faster. ah. in the next science in the golden age, i'll be exploring the contributions made by scholars during the medieval period in

the field of mathematics. the term algebra can be traced back to the arabic word algebra. we're going to the limited on the technology, 40 percent, often with beta fab. they gave us the final building block find that it's covered at medieval times. it is science and a golden age. with jim alkalinity on al jazeera ah, ah, ah, ah, warring drug cartels on vigilante groups in a population call in the middle was your reason for being mature. why do you want this territory? i'm reporting from an empty center of mexico, violence to investigate can an upcoming election change. anything for people living

here? so we're getting to join me john, home and the full report on latin america is a region of wonder, a joy tragedy and yes of violence. but it doesn't matter where you are, you have to be able to relate to the human condition away. no country is alike and it's my job to shed light on how and why me . oh, yeah, molly's job to receive public support on the streets from an influential current that becomes increasingly isolated with the world bank causing payment. ah, hello, i'm darren jordan. this is out there

a life and also coming up is ready for his foster grenades that activists in occupied to roost and running between 2 neighborhood palestinians are under threat