Second Life is not a dedicated virtual globe or virtual planetarium but a free-form three-dimensional programmable space that anyone can use to build globes and planetariums in. One impressive recent example is the virtual planetariums built by Magnus Zeisig, one of Sweden’s most talented SL programmers.

If you visit his space in Second Life, you get to walk around and through a number of exhibitions, including an programmable orrery, walk-through 3D maps of nearby stars and galaxy clusters, and a 3D browsable database of planets, satellite and asteroids — even those with weird shapes like Phobos and Deimos.

Navigating through these exhibits in 3D with an avatar gives a real sense of depth and distance — its an original and unusual perspective on these datasets.

Magnus writes that he will be collaborating with the International Astronomical Union for the International Year of Astronomy in 2009, and he’s also been commissioned to build a larger version of his work for an American university. You can read more about what Magnus has been up to in a PDF newsletter (in English) where he explains his project in his own words. This being Second Life, you can of course buy your own copies of Magnus’s planetariums, and set them up in your virtual Second Life pad.

Tim Parks writes in about Trailguru, a GPS route sharing site with an innovative approach to scalable viewing in Google Earth. It’s another post that practically writes itself:

I thought I would write and let you know about an internet project I am working on called Trailguru to make discovering and sharing route information easier by blending Google Earth, Google Maps, Wiki, and GPS technology. First off, TrailGuru enables you to visualize your exploits in Google Earth / Google Maps. For an example, have a look at a track I captured on a trek I did in Ladakh in Northern India.

By sharing your track, Trailguru also integrates it into the trail maps on the site that are accessible from Google Maps or Google Earth. For example, you can add trail maps to Google Maps by adding our mapplet.

Finally, the end goal of TrailGuru is to share route information and you can also create and share a routes from the captured trails on the site that can be downloaded to a GPS by other users. No more wandering around looking for trailheads.

For example, here is a route for a summit hike in Andalucia in Spain.

We are just over a year into the project but already have mapped over 600,000km of trails on the site across a wide variety of activities (hiking, mountain biking, road biking, mountaineering, etc.).

I had a look at Trailguru, and noticed that the Google Earth link does not lead to a series of vector-based routes delivered via a network link, as you might expect, but instead to rasterized bitmaps of the routes in dynamic overlays. I asked Tim why he chose to go that route (so to speak:-):

I chose to use graphic overlays instead of KML overlays because of scale and speed. I actually started out with KML overlays but the computational effort on the servers once you have a non-trival number of trails in the database became huge. The sheer quantity of KML also started to be an issue — for a heavily mapped section (like San Francisco which has many submissions) the resulting KML was over 10M large which 1) took a long time to download and 2) I estimated that it took 100M of memory in Google Earth to store when decoded. This resulted in sluggish performance in Google Earth. There are some workaround hacks like lowering the level of detail at higher zoom levels but in the end, even these weren’t going to enable us to scale in heavily mapped areas.

So I have switched to tile overlays using the same algorithm that Google Maps uses. The downside to this approach is, of course, that you could have to compute 4^Z (where z is the zoom level if you are familiar with that concept — a typical town level view is at zoom level 12 and street level is at zoom level 15 roughly) tiles. Fortunately, in practice, trail submissions tend to clump together and the number of non-empty tiles is about 5% of that and all that computation is invisible to the user. This method scales incredibly well (0 database lookups to find the correct tile set and then just HTTP image downloads).

Trailguru joins a growing field of route sharing sites, but it is interesting to see how they are each finding their niche, both in terms of specialization (running, biking, trekking, with/without photo support) and in terms of their technical underpinnings — in Trailguru’s case, a wiki-esque motif and a tiling solution for mapping output. (If you want to check out the competition, there is Everytrail, Bikemap.de, walk.jog.run, Wikiloc, Tagzania and Crankfire. Am I missing any?)

• Real World Math: RealWorldMath.org: “Using Google Earth in the Math Curriculum” Lesson plans, a blog, resources and links to other educational sites. Lots of original concepts. (Via Technology Education Know-How)
• MSFT licenses Géoportail content: Microsoft is partnering with France’s National Geographic Institute (IGN), makers of Géoportail, to license IGN’s aerial imagery for Virtual Earth. Finally, a business model for IGN that makes sense to me (although I would like it even more if public agencies made their content available in the public domain). Like I’ve said before, national mapping agencies should let MSFT and GOOG deal with the technology, and focus on the content. So doesn’t this leave Géoportail a little redundant, even with API? As a consumer, why limit your map to France when Virtual Earth gives you the same France and the world as well?
• ArcGIS Explorer tutorial: How to add photos and sound to popups.
• Map-off: FortiusOne’s Sean Gorman looks at the relative merits of Google’s, Microsoft’s and Yahoo’s online mapping solutions. One thing I would add: Google Maps was late to the game of providing homegrown authoring tools precisely because it was first to the game giving developers an API to build such web apps themselves.
• Permalinked KML label URLs: The perpetually unsatisifed Valery Hronusov has further improved his autmatic KML labeling tool: It now provides you with direct permalinked URLs for the resulting KML labels, so you don’t first need to save them to your desktop before you can share them.

It’s raining new and updated Google Earth default layers!

Tracks4Africa: I happen to live in Africa, so I’ve been especially grateful for the existence of the Tracks4Africa layer in Google Earth, a collaborative effort by GPS-wielding travellers to map a continent sorely in need of good maps. The Tracks4Africa layer is far more accurate than Google’s own default road layer, and also includes such essential information as petrol stations and police checkpoints (all of which has come in useful in preparing routes in both Egypt and Ethiopia).

Sometime in the last few weeks, and I suspect as recently as in the last day or so, the layer has gotten a whole lot more sophisticated: It’s turned into a folder containing categorized roads, but also further folders for hiking trails, points of interest, activity destinations and &mdash this is unexpected — “community photos”:

All of this means that some very out-of-the way destinations that I previously had some trouble finding myself on Google Earth are now clearly marked, as is the way there:

ARKive: ARKive (get it?:-) is “a unique collection of thousands of videos, images and fact-files illustrating the world’s species” that lists Sir David Attenborough as a fan. They’ve now got a layer depicting georeferenced endangered species on Google Earth, like so:

WaterAid: is a charity whose mission is to “overcome poverty by enabling the world’s poorest people to gain access to safe water, sanitation and hygiene education.” A whole bunch of placemarks in South Asia and Africa explains WaterAid’s work. For a relatively unknown charity working on one of the biggest upcoming issues in development, there is no better bang for the buck in getting your work known than getting onto Google Earth, like this:

• Google’s “Primary, Common, Local” doctrine: Does Google’s Director of Global Public Policy Andrew McLaughlin have the best job ever? He gets to write long posts entitled How Google determines the names for bodies of water in Google Earth for their official Public Policy Blog. It’s a fascinating read.

  McLaughlin never mentions one particular body of water, lying between Iran and Saudi Arabia and which contains a lot of oil, but I can’t help thinking that his long explanation is an implicit defense of why Google Earth labels it both Persian Gulf and Arabian Gulf; this in the wake of an online petition by sympathizers of the Iranian stance that Google should remove the latter name and keep only the former. When I last visited this issue, on February 24, the campaign was shy of 13,000 signatures. Currently, it has 94,188 signatures.

• Géoportail to get API, KML support: Renalid reports (in French) that Géoportail, the web-based 2D/3D mappping application by France’s National Geographic Institute, will get two AJAX APIs on April 21: API Web2D and API Web2D Pro. The basic one is free, the Pro one will incorporate GIS functionality, such as support for WMS. KML support is also mooted, though it is not clear if this requires the Pro API. (Please please make it accessible to the masses). A 3D API is due in the summer, writes Renalid. Here’s hoping for more generous tile quotas than the UK Ordnance Survey’s OpenSpace.
• Google Sky lawsuit update: If you want a good example of the wasted man-hours caused by frivolous lawsuits, look no further than this page, which charts the progress of the lawsuit against Google by Jonathan Cobb for the alleged misappropriation of the Google Sky concept, an allegation already previously debunked here. The lawsuit was filed Feb 13. On March 28, Google replied, denying everything substantial.
• Webby nominees: Georeferenced panorama photo repository 360 Cities is shortlisted for a Webby.
• Google App Engine announced: This is big. Soon, Google will be offering to scalably host your dynamic KML network links and the apps you build to generate them. One less reason to keep your own server. Cloud, meet KML KML, Cloud.
• Google Earth Pro does reverse geocoding: Somehow, I’ve missed this until now.
• Google Streetview privacy lawsuit pics: The Smoking Gun has them.
• AutoCAD 2009 to Google Earth: Updated Google Earth Extension for AutoCAD Now Available
• KML in the North: April 23, Fairbanks, Alaska: “The Geophysical Institute and Arctic Region Supercomputing Center are hosting a one day symposium dedicated to demonstrating and teaching about the use of Keyhole Markup Language (KML) by researchers at the University of Alaska Fairbanks.” Organizer John E. Bailey adds: “Aiming to make the presentations available as YouTube vids after the event.” I strongly suspect it will be free to attend.

The rush of new content for Google Earth hasn’t let up yet. The United Nations refugee agency UNHCR is also releasing a new layer today in collaboration with Google Outreach.

The layer is not to be found among the default layers, but instead from a new launch page on the UNHCR’s website. Here’s the direct KML link, here’s the press release, and here’s a story about it in the UK’s Guardian.

Two things in particular stand out about this layer:

First, it successfully harnesses the high resolution imagery on Google Earth to pinpoint exactly the location of specific components of a refugee camp — in the above case, a camp in Chad. (This is something that the New York Times layer misses out on, as blogged yesterday.)

Second, the popups segue from the specificity of a location into a direct appeal for aid. The idea is that if you can see a specific instance of a need on the ground, you are more likely to contribute. It will be interesting to see if that is the case.

(Just one piece of constructive criticism, however: For some other placemarks, such as those around Damascus, specific local places are pinpointed while the placemark content actually refers to locations far away (New Zealand in one case). I think it is better not to georeference information than to georeference it inaccurately, as then users start to lose confidence in the accuracy of all placemarks. I think that using placemarks as “symbolic” locations markers is a bad idea — you don’t add information, you merely create confusion between those and actual place markers. And it defeats the purpose of using a virtual globe.)

As the UNHCR’s KML is downloadable (rather than a default layer), you can use it with other applications that support KML. In this particular case, however, only Google Earth is likely to have the high resolution imagery of remote locations that allows this layer to come into its own.

I love my 3DConnexion SpaceNavigator; so much so that I will sometimes lug this beautifully designed solid metal contraption across oceans in my carry-on luggage. Hilarity often ensues as X-ray security personnel puzzle over something that looks suspiciously like a detonator, and is built like one to boot. It’s worth the hassle. There is simply no better way to navigate Google Earth.

3DConnexion is today releasing a lighter, smaller version of the SpaceNavigator, fittingly called the SpaceNavigator for Notebooks. It’s half the weight of the original, 1cm narrower, comes with a travel case and costs USD $129 (vs $59 for a personal edition of the original.)

Wags may wonder why something half the weight costs twice as much, but I think that’s because miniaturization is not cheap, and because this device is aimed at road warriors — there is no personal edition of the SpaceNavigator for Notebooks.

I have not used a SpaceNavigator for Notebooks, so don’t know if it can replicate the solid feel and weight that makes the original such a pleasure to use. If you’ve used one, comment! (Since some will wonder, this is not a paid post, and there is no advertising relationship with 3DConnexion:-)

[Update 11:14 UTC: PCMag has a full review of the device.]