5/3/2023 0 Comments Mw pirates moon atlasAlmost a planimetric map that would drape on the globe. Crater names are billboarded and popups provide details of the crater and its naming.īut designing an evocative terrain for each landing site didn’t go far enough for me. A semi-transparent disk hints at a clickable object. As this too had to be scaled to an Earth sized globe in ArcGIS Online, I had to scale up the buffer distance accordingly to get the craters to sit in their correct position. I used a dataset of craters, which included the latitude and longitude of the centre of the crater plus its diameter to create crater sized buffers. Because of the resolution of the underlying DEM it’s just not possible to publish it at any larger scales. Once re-projected, publishing the colourized hillshade as a tile service from a small planetary scale of 1:591 million to its largest scale of 1:1million gave me a 19Gb hosted tile service. This has the effect of stretching each pixel across a larger surface area when it’s stretched over an Earth sized globe in ArcGIS Online. To overcome this, all of the raster data I used in the project was re-projected to Web Mercator. None of this is a problem in ArcGIS Pro as the projection engine has a specific moon coordinate system. But remember, this is to be published as a web map and getting this to work in an ArcGIS web scene requires a little trickery.įirst, the moon’s diameter is approximately a quarter of that of Earth with a surface area of only 7% of that of Earth. I can invite people in to marvel at its spinniness. It’s all well and good having this great spinny moon globe on my hard drive in my office. Too much and you stretch the limits of credibility. Too little and you’re not adding anything meaningful. I went with a vertical exaggeration of x4 which seemed to work well. The Lunar Reconnaissance Orbiter Camera (LROC) web site also provides detailed and high-resolution data for many parts of the moon, including the Apollo mission landing sites. The Planetary Data System is a great entry resource for moon data (and for other planets and satellites). From this I can derive all sorts of other representations. The basic data requirements are a Digital Elevation model. Fortunately the moon is well served by NASA who host or supply a wealth of different datasets that form the basis of the map. People like spinny globes.Įvery map needs data. Let’s go 3D and make this map a virtual globe. Should it be 2D? or 3D? Well, again, many people have made planimetric maps of the moon so let’s be different. I can publish the map to more people by creating a web-deliverable app. A paper map with 6 large-scale insets? Or a digital multiscale version? The latter. But I also wanted it to provide a focus on the Apollo missions to tie it to the 50 th anniversary of Apollo 11. Well part of what I wanted to create was a single map that allowed people (anyone with a broad interest) to explore the moon and its landscape. What’s its purpose for existing? Paper or digital? Flat or round? Single or multiscale? Plenty of people have made maps of the whole of the moon, or parts of it throughout history, so what’s to be achieved by a new map? You can go and explore, and when you return we’ll dissect it (launch here if you want to see it in a separate window)Įvery mission needs a plan so the first thing to establish is what the map is going to do. These tips should stand you in good-stead.īut first, let’s take a look at the finished app. You may want to have a go at making one yourself, or build a map of a different planetary object (or space station?). All maps are compromises and I’ll share what I had to decide as I embarked upon my mission. In this blog I’ll share some of the decisions that I made in creating my map of the moon, and also outline some of the technical considerations that drove certain decisions. Any excuse to make a map right? But you’ve still got to make the right map, and make it right. Given that I also turned 50 this year (and so did Esri) it seemed a fitting convergence of events. And I wanted to make a map of it to celebrate the 50 th anniversary of the Apollo 11 moon landings, which took place on 20 th July 1969. Our moon is the fifth largest planetary satellite in our solar system and is the only astronomical body that orbits Earth. See what I did? Mashing up the title of a song by The Waterboys with the classic Police hit is a metaphor for the map mashup of the moon I recently created.
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