Sunday, October 30, 2005 at 14:03:32
I have become increasingly interested in exploring some of the inter-planetry remote sensing data sets, partly a result of the BSc in Earth and Planetry Science which we offer here at Kingston University. This is a large area, however I would recommend anyone interested in exploring the topic to visit the Astrogeology group at the USGS. They probably have the best selection of resources currently available for teaching yourself further on the subject, whilst making available a good selection of prepared data and software. A very good starting point (showing my interest in DEMs) is the near-global DEM of Mars:
This is based upon MOLA (Mars Orbiter Laser Altimeter, aboard Mars Global Surveyor) elevation readings that have been interpolated to a regular grid (i.e. a DEM).
Beware that this is a 1Gb download, but is GIS ready!! Simply unzip and go. The rest of the files on the Astrogeology FTP server are well worth browsing through:
One area of particular interest is the availability of dynamic remote data sets. The USGS/NASA are quite pro-active in making data available. This would traditionally have been made through an ArcIMS server, however with the establishment of web mapping standards (specifically WMS and WFS) from the OGC we are seeing non-proprietary formats made available. At the moment it helps if you already have a copy of ArcGIS in order to use these, however this will change with the availability of a new version of ESRI’s ArcGIS Explorer sometime next year. For inter-planetry enthusiasts, the servers you want to point ArcGIS at are:
Thursday, October 20, 2005 at 23:00:00
“Mapping Hacks”, part of the O’Reilly “Hacks” series, was published earlier this summer and has proved popular with a variety of readers (e.g. comment). I’ve finished reading the book recently and thought I would post a review:
This book follows in the spirit of the O’Reilly “Hacks” series which try to open up technology areas by making them more accessible to everyday PC users. Mapping Hacks contains 100 “hacks” that take freely accessible computer cartography software and data, making them do genuinely useful things. The examples draw heavily from the US and the UK, showing the general areas of expertise of the authors. However a US-centric focus on data is not surprising given extensive free access to federally produced data. There are also a variety of guest authors adding considerably to the breadth and depth of the topics covered. This is no short book as, at over 500 pages, it covers many topics in some considerable detail (and is therefore excellent value at the list price of US$29.95). It should be noted that the text is very up-to-date. This ultimately means that some web links noted in the book will change and, overall, the text will date. That said, the books’ strength lies in its’ ability to “push” the edge of “everyday” computer cartography. For this reason, it will remain “current” for quite a while. And in case there is concern over dating content, the authors’ maintain a website to support the book.
The book is organised along the line of nine “themes”:
Mapping your Life
Mapping your Neighborhood
Mapping your World
Mapping (on) the Web
Mapping with Gadgets
Mapping on Your Desktop
Names and Places
Building the Geospatial Web
Mapping with Other People
Each theme contains a dozen or so hacks, some exploring current technologies and techniques, and others developing/extending technologies. The list of subjects is extensive including GIS, GPS, wi-fi, geocaching, satellite imagery, georeferencing, census mapping, web mapping, XML, map servers, PERL, inter-planetry mapping, data clean up and visualisation. As such it is not a course text, specialised reference or practical guide. Think of it as a cross between a practical course and an encyclopedia.
Mapping Hacks covers a wide variety of reader experiences, ranging from straightforward introductory notes, through to extensive programming development exercises. At all stages the reader can closely follow the well guided text, implementing the materials as they see fit, or simply dip in and out picking up tips and tricks. Even experienced professionals will learn about many new topics. The book therefore manages to achieve something quite difficult; it is more or less able to be all things to all people. I have no hesitation in recommending this as a read for those knowledgable in the topics it touches upon, whilst it will be invaluable as a supplementary text to those take undergraduate and postgraduate in subjects such as remote sensing and GIS.
Sunday, October 2, 2005 at 23:00:00
Have come across this excellent web based mapping product. It is an incredibly simple to use Flash animation that allows you to pull in vector data (using GeoRSS files) and raster imagery (either on your own server or via WMS. Yes, it can pull in WMS data!). We have implemented it at the Journal of Maps to show where we have content. Excellent!