 of the new feature that we have for the monthly webinars is highlighting an activity related to this month's topic. This month we're looking back at our planet from arguably one of the most important orbital observation platforms, Landsat. Landsat has enabled us to learn a great deal about both the natural and the engineered world and helps us to monitor changes in various earth and human systems. The Landsat education website has a lot of really great stuff and a lot of it is actually on the USGS site and I hope that Terry talks a little bit about how Landsat really is a partnership between the US Geological Survey and NASA. I'm not sure that a lot of people know that and I think that that's really exciting having been a geologist once upon a time. So one of the ones in particular that I thought was really really cool that you could potentially use in your outreach is and this is actually on the NSN outreach resource page for this webinar is a nice little booklet called Tracking Change Over Time. This is a really great booklet. It's got some activities a lot of it is designed more for classrooms but it's applicable in your public outreach as well and so they can they go through and show how you can use some of the Landsat imagery to see exactly what it is that you're looking at. Can you identify some of the features that are showing up in the imagery? You could make comparisons and so here's a very nice comparison between Salt Lake City taken by Landsat 5 in August 1995 and by Landsat 8 taken in September of 2015 and so there's some significant differences that you can see in these. One of the other things that I thought was really really great is there's a really great little activity about resolution about detector resolution and so you can you know definitely go and check this out. What is the difference if you have a 5x5 or a 10x10 or a 30x30 pixel detector? What does that do to the resolution? Is there such a thing as too much resolution? It turns out that actually too much resolution can be perhaps just as bad as not enough. One of the other ones and hopefully this this is going to come across. Let's see actually I'm going to stop sharing and then reshare because I'm not sure if that's didn't work the last time but another really really great tool that you could use and this was presented to us once upon a time last spring by Kevin Hussey when he came and shared with us NASA's eyes and so there's actually an eyes on the earth and this has a lot of different visualizations you can do you can see all the different earth monitoring missions that are orbiting the earth and then there's a lot of other things you can check out the vital signs if you want to see where all the carbon monoxide is here we have the aqua satellite that's going around and here we have an indication of the carbon monoxide and so this is another way that you can bring some of the earth monitoring imagery into your outreach efforts locally so with that we've got a lot of really great tools I will put the links to these in the chat window in just a few minutes and so make sure you check those out so during the webinar most of you know that we have a chat window and a Q&A window and so please feel free to greet or greet each other in the chat window and put any questions you have for Terry into the Q&A window that helps us to keep track of what's in there also in the chat window if you want to be all if you want everyone to be able to see what you're saying please make sure to select all attendees and panelists and then it'll go to everyone and so now for our featured program Terry Arbidson started her Landsat involvement at General Electric over 37 years ago and followed its evolution with Martin Marietta, Lockheed Martin, and Lightos Innovations as the senior systems engineer she's participated in all mission phases and all mission elements from the spacecraft and the sensors to the data processing and to the distribution of the data all of this has given her a really nice big picture perspective of the Landsat program and she enjoys working with stakeholders such as us and all of you to bring this to the public and she very much enjoys sharing her passion for all things Landsat and so please welcome Terry Arbidson I assume you want me to share my screen now yeah it's all you all me except I forgot to do the other thing come on oh it's already done okay all right um thank you for that introduction and um I'll make sure to cover a couple things in light of what you showed in your prequel there um basically uh this is all about how Landsat is looking at earth from space um we are one of many satellites that are out there they're looking at all kinds of stuff they're looking at carbon water land aerosols atmospheric chemistry sea surface winds gravity you name it we've got satellites up there doing that and that's good because one of the things that we've learned is that this is earth system it is not just land it's not just water it's not just atmosphere it's not even just outer space but everything interacts and works together and we have to keep that in mind the other thing we have to keep in mind is that even just in the 45 years that the Landsat program has been has had assets up in space our population has grown almost four billion be with a b four billion people more than when we started and the world itself is changing and so we really need to have good tools good technology we need to manage these resources and that's where Landsat comes into play everybody's got access to imagery from space now you can get on your phone you can do a google maps use map quest to figure out where you are you can bring up the satellite view everybody's got it but it didn't used to be that way um this awe-inspiring image of the blue marble back in the 1960s when this was taken by the Apollo 8 astronauts it just opened everyone's eyes is to oh my goodness look at the earth and and look at the swirling clouds and the water and the land and what's going on and shouldn't we you know pay attention to that well it was the us geological survey it was the department of the interior tasked with managing all the land managing the interior of our country that came up with the idea that you know we're using airplanes and we're taking pictures but it's expensive we can only do so much at a time why don't you try doing this from space they tried to get NASA interested in this and NASA said you know we're we're busy with astronauts we don't want to do that so back in 1968 um Stuart Udall who was in secretary of the interior with um that's who's standing here on the left and then William T. Pacora who was the director of the U.S. geological survey they got together and put together an earth resources observation satellite program and announced to the world that USGS and department of interior were going to launch a satellite to monitor the earth well that wasn't very popular with NASA nor with the department of defense so they did not want these geologists and land managers to have a satellite up in space and eventually NASA was convinced that they needed to be the ones that did it and so the Landsat program got kicked off in the early days it was called the earth resources technology satellite ERTS ERTS and this is a picture we found all sorts of old photographs when we were working on building a history of Landsat and this is one of the early satellites it's an engineering model a structural model that they put in this centrifuge here at Goddard and they were testing it out it was a satellite bus that came from another program called Nimbus and they put this out there in the centrifuge and they started the test and all of a sudden the cameras they were using to monitor it went blank it was like where'd it go and they had forgotten to strengthen one area on that torso of the spacecraft and it had collapsed into a corner so fortunately there was another one out there that they could use and they managed to do that testing just fine and completed the build in two years I mean that given the early days they managed to do it in two years and it was launched in 1972 and this is an artist's rendition but we've got this mechanical butterfly we had this mechanical butterfly out there in space taking images of the earth from from seven thousand or seven hundred eight hundred kilometers up in space and it had on it two sensors one mimicked what we were getting from the airplanes that were taking aerial photography and this was the return being viticon and basically it was like television cameras and they would take four thousand pixel resolution images so you talk about your high-def televisions that we have now back in the 1970s we were taking four thousand pixel resolution images unfortunately there was an electrical issue with the instrument and it ended up setting the whole spacecraft into a tumble which we managed to get it out of and that instrument stayed turned off the entire rest of that mission fortunately there was a second instrument on there and this one was totally experimental it it had moving parts it had rotating shutters it had scan mirrors it they were vibrating sorry I have a cold so I apologize in advance for my coffee it had vibrating you know all kinds of things that were moving and everyone thought there's no way this was going to work however they saw the first images that came down and this is one of the early images um and uh they looked at that and they thought oh look at all of these spiral patterns here it looks like a moire pattern or something oh there's something wrong here until one of the geologists spoke up and said you know what these are the watchtower mountains and that is exactly what they look like and so that is exactly right and one of the naysayers Alden Calvo Caresis he was a USGS cartographer he actually invented the micator projection he um he came back and and he just he gave in and he said that is a map and he was totally sold on the concept and then from that point on the program is just you know gone a mile a minute um this is an image of Pine Island Glacier um it's actually from Landsat 8 in the background there but what we found using Landsat data was um that we had maps that were totally off base um we also helped um with the new science back then of plate tectonics with mapping fault lines and discovering linements and um we mapped sea ice um we inventoryed various features it was amazing and we had people from all over the world wanting to participate in the program because it was their way to get involved in in the space program without having to launch something they could use space data to improve their countries and that was a very important part of our um of our program um what you see here and that you'll see it a couple times during um during the during this presentation we launched three of those butterfly shaped um spacecraft Landsats one two three um the first in 72 and then 75 and then 78 in 1982 we launched the next generation and you'll notice that the spacecraft looks very much different you have this really tall boom holding this large antenna for communications and this was to communicate with the new tracking and data relay system that was being launched by NASA in the night in the early 1980s the spacecraft itself was very modular you can't see it in here but there are actually handles on a lot of these um systems that allow them to be slid out and then replacement slid back in because this was actually meant to be um a shuttle um serviceable the new things that were on there was a new instrument called a thematic mapper and this picture in the lower left is showing how large that was that's not even the entire instrument within the picture and you can see from the people in it how large it was um here they're working on that that large antenna system and the whole thing including the boom that it was on would fold down and those long arrays would fold in and that would all fit in the nose cone of a of a rocket or within the bay of a shuttle and the intention was to launch a shuttle from Vandenberg Air Force Base on the west coast and to release the spacecraft into into orbit unfortunately that program the west coast launch capability for the shuttle um got cancelled schedule and cost and some concerns about the pads out there and so we did end up launching um on a rocket the big contribution was that we now extended the um spectral resolution of our imagery before this um we were looking in the visible spectrum the voidji bit what we can see with our eyes plus we were looking at near infrared which we can't see but these um were the range of landsats one two and three with landsat four we introduced near and mid infrared as well as a later a thermal capability and so in this image to the right um this is carlton um washington and you can see what may look like clouds but they're actually wisps of smoke coming from forest fires and then there are areas where the fires had been and that were no longer active so somewhere in here there's a fire scar but it's really hard to tell in this image which is just looking at the visible bands red green and blue which is what we would see if we were looking at this from outside of a of an airplane window when we add the near infrared which is what we could see with aerial photography the sensors that we could fly back then as well as um what we had on the early landsats the vegetation in the in the near ir red and green combination of bands all the vegetation comes out red and bare land comes out comes out brownish but it's still kind of hard to distinguish fire scars from other types of bare soil if you add in the um shortwave ir all of a sudden look at what you can see this is a combination of shortwave ir near infrared and green and all of a sudden we've got this ring down here in the bottom center and this is a fire scar this is land that was burned in a recent um fire and you compare that with older scars that are pinkish they're starting to get a little bit of vegetation on them and all of a sudden we have so much more information that we can glean out of these out of this level of imagery um you remember this that we were going to launch landsat four and five from the shuttle well with landsat five landsat four had some problems and and we ended up turning it off because it had um some power concerns but landsat five kept going and going for so long that it actually won the Guinness book of world records for the longest observational satellite of the earth's land surface and that has given us the ability to do what brine was showing earlier with um uh change over time being able to look at how things changed um from early to uh you know early in the in the program and to 10 20 30 40 years later we almost lost landsat five in 2009 right before the the ops crew left um at the end of the day they had one more contact left when they did that they noticed that the the landsat five was tumbling out of control and it turned out one of our gyroscopes had gone to the flu and um they were able to get it back into control um turned off that uh gyroscopes and um and from that point on we had almost um we changed our operations and we had almost 24 hour monitoring of that satellite we got to give it credit I mean in 2009 it had launched in 1984 so it was already a grand old dame and things were going wrong as they do for all of us at that age so um we monitored it very carefully from that point on so now we're into the next generation of satellites landsat six was our anomaly landsat six never did make it successfully into orbit it had when they went to um to do an orbit maneuver to get it boosted up into its final position evidently there was a leap and we we believe that it blew up every entered we call it our our oceanographic mission as opposed to our land mission because it's somewhere in the indian ocean but um that one was built when we were in a commercialization period so we actually had a private company under um under contract to NOAA building that satellite um in 1992 um the uh control commercialization of landsat was ended um the commercial group could still operate landsats um four and five and make money off of them but um and but landsat and they could build and launch landsat six and make money off of that but landsat seven was returned to government control unfortunately landsat six um failed its launch in 1993 and the company kind of lost interest in landsats after that because at that same time there were other satellites being launched like spot and and some commercial satellites and they were getting into better resolution than what we were getting with our landsats and you could make more money off of that and so they were um the commercial company was actually happy to have landsat taken over by the government and to have landsat seven under government control so we did um build landsat seven this time it was it was built on the east coast and to be launched on the west coast we had to ship it over um and this is a picture of the shipping container on this big huge semi-trailer being backed up into the c5 that has been meltdown um in the process we had all kinds of gotchas um the ramp had problems they ended up having to to um add shims in um they're hard to see but in here eventually um they had to shim it so that they could get the right angle there's very little um clearance there um and then in the flight to the west coast it um there was a gas leak from one of the generators on the truck they found a bearing back on the original runway and thought oh goodness the c5 is not going to be able to meal again when it gets to the other end and they wanted to um divert to a different place where they could um have some maintenance done and and our guys said no your job is to get us to vandenberg and so they went ahead and landed at vandenberg and everything was fine and we successfully launched in 1999 um um brian mentioned resolution um starting with landsat four we had 30 meter resolution capability with our thematic mappers and then later with the enhanced thematic mapper plus that flew on landsat seven and what that does if you want to get an idea of what that means 30 meters is about the infield of a baseball stadium this is target field in minneapolis minnesota what we got with landsat seven was a panchromatic band this is one of the things that the commercial satellite one commercial operator wanted to add to landsat six and what we flew on landsat seven was basically landsat six's instrument with some more um tweaking and improvements done to it but this 15 meter would get you between home base and the pictures now so you get this additional level of um resolution spatial resolution and we actually use that to clarify um the other images done with the other bands to to sharpen them up it's called our sharpening band um but if you were to look at just um these pixels you wouldn't necessarily you know if you had a tiny pixel if you had one that's the commercial size that shows you the the pool in your neighbor's yard or shows you just one of these bases it doesn't show you the context you don't know if you're looking at a schoolyard field or if you're looking at a major league stadium like this one or where you are so the value of resolution special resolution is depending on what you need you first can see like the east coast using a weather satellite then you can narrow it down to um a state or a county or a neighborhood using moderate resolution like our landsats and then you can get down to your neighbor's backyard or um you know the details of the little boats that are going down the river or whatever and that gives you you know the the really gory details you everything has its place the landsat archive um as of january our goal has always been global coverage one of the things we discovered was due to various reasons through throughout the program life we haven't really had global coverage until landsat seven um and the color depth here um when you get into the blues you're getting into almost constant coverage from landsat constant means every 16 days and um oops i'm gonna back up on every 16 days and so um the the ability to monitor all the changes that are happening every 16 days over the past 40 years is just a tremendous amount of information to support global change science landsat seven just flew its 100 thousandth orbit on february first um uh just this last friday and that's about 15 round trips to the sun the uh that's the ops crew in their control center and they had a cake that showed the odometer changing over from from five nines to 100 000 and that's just amazing um we are currently building landsat eight um it's actually being built in uh arizona and so it's going to get transported out to vandenberg um and will be launched off of an atlas five or was launched off of an sorry we are building landsat nine we did build landsat eight um it was also built in arizona those two are like um very close twins to each other um not quite identical but almost identical twins um and it's being launched on delta five um five years ago last sunday um february 11th um we launched landsat eight so it has met its mission um specification its mission life of five years but like a good landsat it's just going to keep going and going and going at least that's our prayer so over those years things have changed a lot um this is some of the early um image analysis consoles and some of the data we did not have pretty digital data we were back at analog things that um like photo prints um working with film negatives using line printers and over strikes to get different shades of gray to show us what the different changes were like these are probably farm fields and a river or a stream that's going through and such a change that is the other thing that has changed over time is the um uh cost of data over the years it got up as high as 4400 for a single scene since since 2008 data has been available for free the peak year of sales before that was um uh 57 000 scenes and the year or i think it's actually the month after we went to free data it was in the millions um of data that was downloaded by folks so as i've mentioned everything has gone out of end of airbase um all of our landsats are in a polar orbit um and i have a video on that in a second so i won't go into any further detail on that um all of those that have gotten to orbit have outlived their design lives and one of our key um precepts for this program has been continuity all our data is inter-comparable we have got tremendous calibration and validation folks that make it so that this stack of data which is the same scene through the years you can actually take them and do comparisons and track change over time and that is just invaluable and we've been doing that for 45 47 years so i'm going to play a video now and this will describe our orbit and orbital swap and why we go with a polar orbit as opposed to an equatorial one which is what the space shuttle does and find that cursor again as a landsat satellite flies over the surface of the earth the instruments aboard the satellite are able to view a swath 185 kilometers wide and collect images along that swath as the satellite proceeds through its orbit the spacecraft travels at approximately 4.7 miles per second the satellite travels from north to south while it's over the sunlit portion of the earth and travels south to north over the dark side of the earth one orbit takes about 99 minutes so that's about approximately 15 orbits in a 24-hour period the orbits maintain such that after 16 days the entire surface of the earth has come within view of the landsat instruments while sunlit and then on day 17 the first ground path is repeated so we get to view the entire surface once every 16 days generator there was dr jim irons he is the landsat eight project scientist and one and has been involved in the landsat program forever um this just as an example of some of the stuff i'm going to go through some of the applications of all this wonderful data on august 25th the virgin islands in the top image are looking as you would expect a little bit cloud covered and lots of green lots of lush vegetation on september 10th after her king irma went through you'll notice that they're very brown what we're seeing here is defoliated trees from the wind mud and sand coming in with the with the flooding waters that overwhelmed the vegetation another application is in the agricultural areas on the left it's very easy to see the healthy vegetation that's growing are the near infrared band really responds to chlorophyll or i should say the other way around the chlorophyll and plants really absorbs the um the near infrared and or reflects the near infrared and so what we see um in our imagery um are these shades of green that um show us where the healthy crops are if we go in and we start using some of the other parts like the shortwave ir and thermal um ir we can get into more detailed evaluation and analysis and looking at things like evaporation of the soil soil wetness and also looking at water loss from plants through transpiration and that's called evapotranspiration and that's actually one of the newest applications that we're seeing um now that we've had some really great thermal band data available off of Landsat 7 and Landsat 8 the other thing that now that data is free is we can do global analyses can you imagine getting a 100 um nautical mile image square image of every bit of land on the earth and paying 4400 dollars for it it's just totally unaffordable but now that data is free we can download the entire archive we can analyze tree cover for the entire globe and what we see here in in shades of red are the overwhelmingly forested areas of the world and we can do analyses that for example would show forest loss between um 2000 and 2012 it's hard to see um probably for you guys but up in the um northern boreals well that's redundant up in the boreal region there are some pinks showing um 70 or 80 percent or more loss of vegetation we see it a little bit here in um indonesian area a little bit in the um brazilian area and then again up in the boreal regions over um canada analyses like these were just totally not possible beforehand music so this is running through that a second time if you just look at you know pick an area and watch it as it changes over time it's amazing how how the landscape is recovering from that terrible overwhelming onslaught of mud and ash that they got and uh it's it's enabled us to understand how well they have um or how forest under those conditions can recover it's another aspect of um the ability to use landsat data to monitor the earth here's um another great thing one of the first inventories of coral reefs was done using landsat data in fact i remember getting an email from um one of the uh government officials on new caledonia saying hey um you've got a uh a scene that's identified as being this particular um atoll and uh we've been trying to locate it for years and send us the coordinates that you found in your imagery because we can't find it um so that's you know totally an amazing kind of email to get um this is actually a brand new island um island back in december 2014 in the tonga um uh archipelago um this new island was born from a submerged volcano that erupted it was only expected to last a few weeks but um it's actually um it has it has it's this tough material tv ff and geologists now believe that this is going to last anywhere from six to 30 years and it's really being studied by folks like dr jim garvin down at nasa headquarters who is very much into mars and how we're going to explore mars in the future because a lot of the same kind of volcanoes um come up with the same kind of materials there and so he's really looking at um island volcanoes and other desert volcanic regions of the world using landsat data to understand what kinds of things they'll be able to see and what best um sensors could be used for mars as we launch more and more um missions towards mars um and basically this has been a really fast um review of the last 45 years the landsat program you can always read the book um i'm part of the landsat legacy project team we just published a book under the auspices of the american society of photogrammetry remote sensing it's available at asprs.org slash landsat i think brian's going to post this later the folks that were involved in this book we all have a passion for landsat we've been involved some of us since before the landsat one launch and it's just been an amazing journey back into the history of landsat and what actually got it started and all the different hurdles as well as the amazing discoveries the development of technology and the help that we've been able to give to science in establishing a global science um for the world so i guess at that i'll stop and take questions right well thank you so much and so we do have a few questions that have come up and so if anyone else has any other questions and if you inadvertently put them into the chat window we'd appreciate it if you would put it into the q&a window so that we can find it more easily so william asked he uh had it sounds like he had some early exposure to landsat data says that in 1970 he was able to get a magnetic tape of landsat data from nasa to use for his undergraduate degree project and contained only one image in four spectral bands so can landsat still be acquired by private citizens for free what format would be used and so i think that you partially answered that question but what uh maybe to expand that question uh what's the format and how what's the the how do they go about getting to the data um if you go out to landsat.usgs.gov um you can get data there they have several tools available that help you visualize um where you're going actually um if i i don't know how to operate this very well maybe i shouldn't do that okay um i was going to go out and and just go out to the um to the site but they have tools there that you can use you can locate the area that you're interested in what you're going to get is digital data so you're actually going to get um data downloaded um to your computer and um you don't need to get a magnetic tape for a cd or anything like that you actually get the data itself and then there are programs out there that will manipulate that data for you um including some that are um that are available through google earth um and other free tools that are out there so there's a lot of ways to do that or you can just browse through um their site and find pictures you can also get jpegs um if you want to you know build a poster or just um have something on your on your desktop for your computer um all the data is free they are in the process of putting together more um uh evolved products right now you get a product that is geometrically and radiometrically corrected it has been corrected to um make up for any terrain differences within the context of the image so any geometric um distortion because we've got a a 3000 foot mountain in the middle of your scene is going to be accounted for um it they are now working at giving you surface reflection products so that right now we measure the reflected light up at the satellite so top of atmosphere correction we are now taking out the influence of the atmosphere so that now the data values that you get are down at the surface um so that's a huge step forward atmosphere correction or taking out the the impacts of the atmosphere has been a big bugaboo um has been the problem to solve for the last 15 years and they've done it and so we're really really proud of that and um they're gonna start putting out these level two what they call level two products um with surface reflection um very shortly if not already great so Darian has uh got a number of questions but uh let's go with the first one that he asked and so what is the current resolution that Landsat has and I know that there's probably been a variety of resolutions and you know exactly what would you be able to see you know given the resolution what's the smallest thing that somebody could see um the resolution um for the current Landsats that are up there now Landsat seven and Landsat eight is 30 meters um for all of our reflected light bands so um red green blue the near infrared and the shortwave infrareds um and then we have um panchromatic bands that are at 15 meters panchromatic goes across it's like for Landsat seven it's it's red green blue and near IR all together as one band one bandwidth combined so it's basically a black and white picture it's a single band but it's at 15 meters and then um we have thermal data thermal data is emitted light it's it's it's heat basically why they call it thermal it's heat and that on Landsat seven is 60 meters and on Landsat eight is 100 meters we kind of went a little bit backwards on that um it's 100 meters and it's so it would appear a little more fuzzy than uh than the regular reflected data now what can you see you can see neighborhoods and let's see actually for example this is um what I'm showing you now is a map that was done with reefs um and they were able to to um to see all the different kinds of reefs um it's not just that there's coral reef out there but that there's fringing reef and there's pinnacles and patches and there's a shallow barrier reef and a deep reef and they were able to tell all that using using the data um oh come on you can go backwards uh here we're seeing um fields farming fields we can tell um 130 meters is like 100 feet so we can see details of 100 feet we can sharpen that up some sort of um make it high depth and we did that when we went from Landsat seven to Landsat eight by increasing the number of pixels uh or the number of pixels we brought down um instead of uh of um bringing in 12 we're bringing in uh 14 so so it's sharpened it up and the differences between Landsat eight and Landsat seven is like between high depth and and regular um channels on your tv you can still see everything it's just really sharpened up but in general um we can see fields um we can the agricultural extension agents really love it we can see as you showed earlier brian um the growth of cities over time um we can see how they've expanded we can see the streets and all that we just can't see the details of the cars and the driveway or the pool in the backyard or the new patio they put on but we can see how many houses are on a block and the streets that are in that neighborhood and then the town that's nearby and the park and all that kind of stuff a little bit of a clarifying question i know that usually and astronomers have uh do a lot of a lot of them do some astrophotography and so they're very aware of the resolution of their own cameras that they're using and of course people with digital cameras are aware of that um you referred to the i guess the pixel density and you just said i think 14 pixels and usually people think about you know pixels on a number of pixels on a side and so could you clarify that a little bit yeah yeah you're right i and i knew it as i was saying it that i had the wrong word and i couldn't remember what the right word was bits we're bringing down 12 each measurement we make um in landsats one two and three we could only handle eight bits i mean eight bits worth of data for each each measurement um basically for each pixel we could only do eight bits um landsat four and five we um and i took it back it was even less than that on four and five we had nine bits measured on board we brought down eight on landsat seven we have nine on board we bring down eight on landsat eight we have 14 on board we bring down 12 and the landsat nine that we're building now we've got 14 on board we're going to bring down all 14 so landsat nine is going to be even higher resolution um more high def in essence sharper um than eight which is sharper than seven so so that's part of the technology that's evolved over the years is that and then the technology that that um was illustrated by that earlier question of data own products only being available on tape and sometimes it took um uh nine inch reels it would take like seven of them draped on your arm was one was one scene one for each of the bands and then that's what you carried over to your computer and you just read them in one band at a time and now it's just a download a quick download of a couple terabytes and there's your data okay well that was good and so that that you know kind of clarifies me because a lot of people that are familiar with um digital cameras are aware of you know image depth and and uh and so that really clarifies that so thank you um kind of staying with this idea about agriculture richard asks any idea of how much landsat has contributed to increased agricultural production say per farmer per acre or something like that has it contributed it has contributed and there have been studies done um by various think tanks that evaluate the the monetary worth of the landsat program in other words what's its contribution versus the cost that takes to launch it and all that as part of our trying to convince the government that look you know we're bringing you back you know a hundred time your investment the return on investment is amazing to keep funding the program you know it's it's it's a question but um uh it's becoming even more productive it's becoming even more valuable because of the introduction of the thermal data and our development of applications like this one on the right which gets us into evapotranspiration and the ability to monitor the use of water especially in our western states um in the u in the u.s. um where water is is such a high price and and a valuable commodity um and so they can monitor the fields that way and be a lot more um less aggressive on the use of um herbicides and um and insecticides and fertilizer um based on the information that they get back um agriculture was actually one of the initial reasons why landsat was launched um back in the um in 1970 I believe it was um we always got our information about what was happening around the world with crops through the cia um the central intelligence agency had agents on the ground it it referred to um in country sources and it estimated what the um crop futures were around the world and that went into how we would value our surplus and what we would do with our crops um and it turned out that in the early 70s Russia had a humongous wheat crop failure and no one knew it the cia didn't catch it um either it was hidden or they just totally missed it and as a result the russians came and bought up most of the u.s. wheat surplus at a very favorable price which would not have been so favorable if we had realized that they had no wheat of their own and once that was learned the the um some folks from uh um uh johnson space center actually were called in they had been doing a lot of agricultural work using the photographic um monitoring and they were called into the white house and asked we've got to do something you've got to figure it out make it work um don't let this happen again and so um when the concept of landsat came around it just was a perfect match and we had other issues that we were following as well there's a corn blight um that was some sort of a corn fungus i believe um that was being monitored and they proved that landsat monitoring from space could actually help them find all the crops and monitor the spread of that so over time it has proved invaluable and it's getting better and better with the addition of more bands um more careful crafting of the bands so that we avoid areas of water absorption in the spectrum and get a clearer signal and so um it's it's a very useful tool it does not get us to precision agriculture we don't have the the fidelity to get down to um of the small crop areas especially in europe and china where the the fields are regular shape we are regularly shaped and very small and um we don't come around enough we have two satellites up there so we get eight day repeat every eight days we have either seven or eight is is imaging um but we need more satellites up there we would love to have a sustained imaging system which is hopefully going to make it through the budget process and we would have three four maybe five satellites up there and we would coordinate with international satellites there's a european satellite system called Sentinel-2 which is the very first one in all the years since we've we've been doing this that has come up and said we're going to do what landsat does free data and and we're going to do global imaging we're not going to point and shoot and just try to sell our data and and answer requests we're going to make sure that everybody gets the data and that we're taking the whole world so we have a partner up there and we're really excited about that and we're making sure the data are comparable between the two systems i think that one of the things uh also on on nasa earth observatory there's a lot of imagery that shows up in there i think that um it's probably pretty evenly split between uh astronaut photography from the iss and and landsat but a lot of times you see these comparisons either in time of scenes or sometimes you see ones with charts where they're actually showing you know things like the ozone amount or something like that which kind of brings up a question um based on what derian asked he said can landsat photography is very specific here can landsat photography be useful for oil and gas exploration by monitoring methane emissions from seeps and so i i guess that speaks to the question is is um is landsat sensitive to those sorts of things or is it uh or are those outside the realm of what their its capable of doing um landsat only looks at light so we're only looking um at reflected light or at emitted um light in the thermal region of the spectrum um we're not looking at chemistry um however the oil and um mineral exploration folks were some of our first and largest and continue to be very avid users of landsat data and they're using geology to find their their um goals their resources so um the fact that they were getting geological data over the world without having to fly um uh planes and without tipping their hand to um competitors as to where they were looking um gave them a real leg up and so um exon and and well so back then and um BP and all those guys have been tremendous users of landsat data and although geology doesn't change land cover does change and so areas that were covered um at one point and now get denuded perhaps or um the snow melts geology becomes obvious and so they um they uh have new places to look so they are definitely using um landsat for oil and mineral exploration well we're running a little bit late but there is one other question here and i think i know the answer to this one but i want to hear it from you and and i suspect that it has to do with field of view um and so richard asked can you see the rivers in the sky and i'm guessing that he's meaning the uh weather phenomena of the atmospheric rivers that have brought all these waves of moisture to the west coast the only way we see them is by seeing the clouds um we're we're not radar we're an optical system so if there's um clouds over the fields then we don't see through them down to the fields we just see light reflected off the top of the clouds so in that sense we see it but um we're not the right mission for for um monitoring those rivers or for seeing them on the other hand um are one of our early science teams um for landsat seven had a cloud specialist in there and he used landsat to actually get pictures of the clouds he wanted to see the surface of the clouds in their structure and um and we have a very um you can see it out on earth observe on earth observer um the carman street vortex um phenomenon when uh wind pushes clouds over a piece of land that's like a mile high or more and um and then that land coming up interrupts the flow of the clouds if it's a low cloud um formation and then induces vortices and you have this wonderful picture of vortices just going on and on and on and they're just beautiful yeah i think i've seen that they are beautiful well terry if i could get you to uh stop sharing your screen i think uh that's uh brought us to the end here so i want to thank terry for uh you know very graciously staying you know a few minutes late here and for uh being up what's uh past my bedtime if i was on the east coast so thank you very much for sharing this was absolutely fascinating the imagery was just great and uh we did have a a couple of inquiries do you mind if we share your slides with with the people i i know that a lot of people would like to be able to see and perhaps even use it in some of their outreach or is that fine you yep that's fine with me and there are actually notes um in it's a powerpoint there are actually notes and um uh in the notes are sometimes uh the photo credits or um other resources such as um websites that you can go out to get more information okay so this is fantastic well thank you so much terry this is great well that's all for tonight everyone you'll be able to find this webinar along with many others on the night sky network website in the outreach resources section each webinar's page also features additional resources and activities we will post tonight's uh presentation on the night sky network youtube channel in the next few days as well as on the outreach resource page