saudi consulate in istanbul in october on pay a seven day middle east tour will also include visits to the united arab emirates egypt and cattle. and outstrip comes as the saudi court held its first hearing on casualties case with the death penalty being sought for five of the eleven suspects the united nations human rights office has called the trial not sufficient. pakistani leader imran khan has met turkey's president on chairing a two day visit to the country it comes as pakistan has transferred control to a turkish charity of all schools run by u.s. based turkish businessmen for two a good len turkey accuses him of orchestrating the two thousand and sixteen coup police in sudan a fired tear gas to disperse dozens of protesters chanting anti-government slogans as they left a major mosque following friday prayers the incident in durham and was smaller than all the demonstrations seen in sudan over the past two weeks those are the top stories coming up next science in a golden age. understanding

the universe and the vastness of space is at the forefront of physics and astronomy research today everything from white dwarfs and bread giants to neutron stars and black holes but imagine trying to make sense of the cosmos before telescope for even invented. well between the ninth and fourteen centuries scholars from the slamming world consolidated and refined the astronomy of earliest civilizations and came up with ideas that have deeply influenced the stormy right through to the

present day and leave me a british professor of physics but born in baghdad and i'll be taking a look at modern day astronomy and navigation and exploring the contribution made to these fields by the scientists of the golden age. why would the scholars of the stomach world so interested in astronomy. one reason is for navigation. people have been using the sun than the stars to fall on their way around for thousands of years. i'm heading into the desert outside of doha

and i'm using the sat nav 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 going to call someone to help me. is a businessman in bed with me with a deep knowledge of the desert in the bed of which way of life. has always been a crucial skill for the bedouin. so as a bedouin how do you find your way around the desert so accurately. during the day. we know by the sun. this side or the side if it's in the middle sometime we get lost during the night we'll go by stuff.

you're familiar with. which is in the north yes it's always there and we have. a lot of names like. george. and we know the direction by and by that of the stars. but when by by the way they have a very unusual sense of direction it's in their d.n.a. one i'm driving. i don't know if you just. said ali was not it was this not immediately. thank you. this one is navigation astronomy was also important for the measurements of time. for example the islamic calendar is a lunar calendar where the months are determined by the phases of the moon. during

the golden age astronomers study the movements of the moon to predict the calendar more accurately the twelve months making up the islamic year shorter than the earth's orbit of the sun. months and religious observances like move from year to year. calendar is a short thought by eleven days and every thirty or thirty years about. that will cycle for example. yes for example if i start for starts now in general which is in the middle of their winter. after thirty three years it will come back again in general. these days even someone like me can pretend to be as knowledgeable about the night sky because i want to show you this i have in my tablet you see it shows why.

the night sky. let me see if i can see the north star you saw you know that's nor. have. i thought they call it there not a star well that's another name for it but it's its. i don't need to know that's north i can hold. and fine no the north star is there then we know you know the direction right and i should know my directions. and this app on my tablet allows me to scan the night sky and identify the stars and planets is the modern day equivalent of the ancient star known in arabic as is each now in the early ninth century the. moon the ruler of the powerful islamic

empire was a man obsessed with scholarship and learning and he commissioned a group of astronomers to produce an muzi 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. the verified tables. in a sample i'm standing on the very edge of what i can look across asia on the other thought of the bosphorus. from the seventh century. and its

people spread out of a arabia to asia in the east all the way to spain. but the call costs so much land they had to be great navigators. throughout antiquity maps. drawn by hand and relied on travelers accounts for example before the golden age the greek astronomer ptolemy had compiled lists of over eight thousand coordinates detailing the positions of oceans landmarks and cities in the ninth century the ruling khelifa of baghdad a. commission to group of his scholars to make a new map of the world and to improve on ptolemy's data. at istanbul's museum of the history of science and technology in islam dr left quinn turn is a scholar of ancient geography together we're looking at moon's map this map dates

back to the reign of mahmoud in the first third of the ninth century the floor of period of a replica islamic science in baghdad i guess what was different about is that they wanted to improve on on the greeks maps absolutely they measured the. after and of course the but that didn't even exist in the time. they had to i guess add all these new cities medicare as well as well absolutely so there were a lot of more precise caught in the moment movement was from the very early years of the golden age here we have an example of a map several centuries later the culmination of of geography in islamic empire it's a map of the world but it's not one that i recognise i don't see any countries that look perfect they should all maps asshole thwarts oriented so africa is always

on the top the top so in fact so this is upside down it is upside down we can turn it recognize it. that's better. ok so now i see arabia and the mediterranean so what was new or different about this man you can see the shape of the mediterranean shore of. and became more precise even north of the shape of the sea and it was this map then of course led on to advances in europe absolutely mental that was only a sort of an obvious. so how did the map makers of the golden age determine such detail measurement that used a versatile scientific instrument called an astronaut. i've come to the museum of islamic art where among their many artifacts they have a wonderful collection of astrally standing back almost

a thousand years and i'm hoping that one of their curators dr nor can is going to tell me what's special about a couple of them. the lovely thing about astral legs nor is that before the invention of the telescope these devices were incredibly important how far back the astral apes go when were they first well adapted the story in say they go back to three hundred b.c. in greece and the word comes from the arabic just above exactly originally from the greek to grasp the stars because actually what you have here is a handheld model of the sky. 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 multi-functional us troops in many ways with the computers of the 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 times you could navigate you could measure the heights of buildings or distances there are all sorts you can see all that exists with this disc because of course these are all moving parts is a portal to two to take it apart yes and seeing it and when we can a single map of the stars would only be. corrects for one location on the earth but these sophisticated esther labels were designed to work in many places a later astrid such as the seventeenth century astrid had a number of different plates 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 your astraweb to do so wherever you were in the world you'd use the would have of the scarves with all its intricate markings in measurements to use an astral leg you already needed a good working knowledge of astronomy so here we have five plates inside you then

adjust this. so you put the right plates in position yes you take a measurement of a particular star. and then you and then you adjust the reach over the correct plate and that gives you a map of the sky where you are. asked . for astronomers in the golden age modern astronomers have access to a vast array of instruments such as this the lovell radio telescope bank in the u.k. . during the golden age astronomers would come together from across the world to cooperate and that way of working is still imbedded in astronomy today astronomers working with this telescope often collaborate with other telescopes and astronomers

internationally unlike a conventional telescope it doesn't capture light through a lens but rather uses a massive kick that collects very weak radio signals from deep in space allowing us to map the universe in ever greater detail. now tim because the level telescope is a radio telescope it theming the sky in a way that we can't see in every sees the visible universe i've got a picture here of what the level telescope sees if we could see radio waves this is the way the sky would appear that's our 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 is look at planets around of the stars there's a picture here of a young star in our galaxy called. the stars at the center and then around it there is a disk of gas and dust but the interesting thing here of the dark circles we think

that there are formed by planets that of that have formed inside the disk and as those planets circle around they sweep the gas of the dust and they leave behind these empty gaps it's amazing isn't it that we're not talking about planets going around our own sun system these are planets going around distant stars hundreds of light years away and many many thousands of these parts maybe billions in fact in our own milky way galaxy 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 us all the locations of the various radio telescopes across europe out into china don't need to south africa and we even with these telescopes with a russian spacecraft that's all but in the earth so weak so we end up making telescopes the size of the planet or even larger the point is they're all contributing their own data so a single task will give you

a poor view by working together with these telescopes you know in these other countries we all joined forces to make this planet sized telescope shows the detail this idea of scientists working collaboratively together particularly in the stormy is something that goes back a thousand years to the golden age it was in baghdad around the ninth century. when we first start to see astronomers working in groups to solve big problems in astronomy something that the greeks didn't do something that only really emerged in the golden age and has survived so successfully to this day. one of the most important observatories of the golden age was called the observatory built in twelve fifty nine in persia for the greatest. when the mongols invaded they captured the mountain fourth of a long moved well to see worked not only did he convince the mongol general hoar

larkhall or helluva car to spare his life he convinced him to build him a new observatory in return promise to provide the general with his astrological chart so that he'd know what day to go to battle the rather observatory became the most important of its day and a great hub for international find to fit collaboration. of course what's great about the rugged observatory in the storm is that work there isn't the observations they made they didn't have telescopes but it's the mathematical tricks they developed that will be influential in astronomy for centuries to come and i want to show you something here so this is a diagram from two c's 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 it got

incredibly complicated of course the greeks believed that the earth was the central source system and in order to make the mathematical model fit the observations of the way in which the planets appeared to move on the sky they had to put all these ridiculously complicated features into it to the model it got very very messy circles within circles going around other circles and that's that's where. his genius comes in because this diagram that to see couple simplified a lot of that 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's turned out to be a very useful trick that simplified a lot of that complicated math. but what's really fascinating compare this text written in arabic. with this one is an identical one but written in latin and what's fascinating is the letters labeling the points followed the arabic alphabet not the latin alphabet so. a b g d clearly whoever through this

knew about two c's work and that was a couple where the man who drew this was kind of this so this is copernicus who came up with the idea that rather than the earth being the center of the whole system it was the sun senator and all the planets including the earth revolved around revolved 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 and yet what's so fascinating is that this was built on two she's ideas yes so it shows the continuity of science copernicus owes this debt to these medieval astronomers from the goldeneye. islam itself was 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 day some religious festivals according to the moon a calendar astronomical infinite yesterday played a very important role in this. were in the early in the load. was. one of the requirements of islam was 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 a problem the scholars of the golden age were very. proficiency mapmaking but as the empire grew and stretched from india in the east all the way to spain and in the sea in the west it was much more of an issue because the scholars also knew

that the earth wasn't flat now why does this matter well if you were a muslim in cordoba then facing towards mecca if you just looked at a flat map would involve pointing roughly southeast or on the globe it's different if i attach this string one end to cordoba and the other to mecca then you see the line actually takes you east to begin with and then curves down to the southeast so it's not at all obvious without understanding that the earth is a sphere this meant that these stores had to develop an area of mathematics called spherical geometry which was exceptionally advanced four thousand years ago. but to use this very cool geometry first needed to know the size of the year the ancient greeks had provided several estimates of this. their method was clever but crude it involved measuring the angle of the sun at

a particular time of day and then walking in a straight line in a particular direction until that 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 three hundred sixty degrees that would give them the circumference of the earth be early night century. 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 one hundred kilometers a method that was prone to error. two hundred years later in the eleventh century the persian astronomer 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. l.b. really 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 heights elbow room he then had to climb to the top of the mountain and armed with an astral eight and a plumb 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 the rooney's mountain now looking across horizontally he measured the angle of the. horizon. this angle here

now if you draw two lines one through the center of the earth from the mountain and the other from where the line touches the horizon you end up with a right angled triangle now knew the angle he measured is the same as this angle inside the armed with these two 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. multiplying this number. gives him the complete succumb friends he got to within one percent of the value we know today about forty thousand kilometers which is pretty remarkable. it's easy to think that astronomy went to sleep after the ancient greeks didn't wake up again until copernicus in the fifteenth century but developments in

astronomy continued in spain the middle east and central asia throughout medieval times through a nascent scientists of europe who created modern the strong army were building on the work of people like rooney and to see who in turn were building on the knowledge passed over to them from the earliest civilizations today in the twenty first century international teams of scientists are still looking to the stars and mapping the cosmos using ever larger telescopes but we must remember that they owe a huge debt of gratitude to those astronomers of the morag observatory. the. next time we are cover how the scholars of the slammy quote mathematical science. 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 i made that step

to the cubic equation. 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 existed. and we reveal how their legacy has led to the mathematics behind the fastest car in the world. is the longest standing recorded history and up till this point nobody has proclaimed that's about to change we're going to go a lot faster. in the next episode of science in the golden age i'll be exploring the contributions made by scholars during the medieval islamic period in the field of mathematics. the term algebra can be traced back to the arabic word job or we're going to the limits of modern technology forty percent falls to the speed of sound they gave us

the final building block find they discovered it met evil taunts is still science from a golden age with jim. on al-jazeera. bigger and potentially more dangerous that's the best way to describe what's happening with a smoking alternative known as faith that i enjoy the taste of it and not because the harmful effects of what smoking does between two thousand and thirteen in two thousand and fourteen alone the start tripling in use among us high school students and head to head comparison ysaye versus conventional cigarettes which one do you think has helped my opinion i think they're both dangerous take no one else is in.

you stand the differences. and the similarities of cultures across the. al-jazeera. nancy pelosi goes to the white house as donald trump and congressional leaders try to find a way to end fourteen days of government shutdown. from joe harbor when i'm come all santa maria and this is the world news from algiers and. we as you know have been pressing for justice in the shoji case for months now.