Altadena (CA) - A research scientist at the Planetary Science Institute (PSI) named Robert Gaskell is assembling the first pieces of what will eventually become a full 3D surface map of the entire solar system. He's pulling data together from multi-angle photographic, lidar, radar and other geometric data sources, all captured from real space flights. The data is processed through custom software he has developed over the last 25 years called stereo photo clinometry. The result is extremely accurate 3D surface data - and a growing database of planetary bodies which have been so mapped.

Gaskell's algorithm can combine several forms of raw data input to create the maps, but it was originally designed to determine height data based on an analysis of the shadows created on a surface of a planetary body by the sun. In some instances, Gaskell is literally combining data from 100s of images taken of the same spot with different angles. The compilation of so many images helps produce hyper-accurate 3D data due to the many samples and a reduction of possible error.

The reseracher’s algorithm-generated 3D data was recently put to the test. His data was compared to the true Lidar-based 3D surface map data of an asteroid named Eros, captured by the NEAR spacecraft which entered into its orbit in 2000. Eros is a fairly large odd-shaped asteroid measuring roughly 13 x 13 x 33 kilometers. An error of only 14 meters or about 0.1% was found. Lidar is a type of range-finding system similar to radar, but instead of using radio waves, it uses light.

According to NASA, Gaskell is currently using images for a 3D map of an asteroid named Itokawa. It will be the most accurate 3D map of Itokawa they have to date with better than a 40 sq cm per pixel surface resolution. This is more accurate than one could get with an average GPS.

Error cause

Gaskell recently announced it is highly probable the resulting error in his algorithm-generated data is the result of incorrectly reported spacecraft data rather than algorithm-generated anomalies. This makes sense, because I was taught in school that we went to the moon with only four significant digits of pi (3.1416) because that's all that was available for the "Pi mark" on the Pickett slide rules used back then. Hence the expression, "It's close enough for the moon".

For additional proof that NASA's measurements aren't always 100% accurate, in 2007 NASA reported that a comet may strike the surface of Mars and that one of the two Mars Rovers may be in a perfect spot to capture the entire thing on video. NASA gave an initial path for the comet that varied by several hundred miles. On one side it was striking Mars squarely, on the other it was clearly missing Mars. Their explanation for the range was "due to sampling error," meaning that the devices they used to compute the comet's trajectory did not have enough accuracy to report the comet's true position, only a "good guess".

Gaskell ultimately believes he will eventually be able to correct for these errors and recompute the databases with an even greater degree of accuracy than the 1/10th of one percent he's achieving today.

Conclusion

Whereas Google Earth today allows us to go anywhere on the planet and see the Earth as if we were looking down on it, Gaskell's system will ultimately take that to amazing extremes. Just imagine sitting back with your family taking a virtual flight to Mars, Saturn or Europa, one which removes the travel time but allows you to visit the entire planet at your leisure. Hot spots can be chosen and I'm sure it won't take too long after that before the online 3D Avatar communities begin creating a type of "Total Recall" environment on a virtual Mars, whereby virtual industries are created and hours and hours of free time are spent "working on Mars".

With what will eventually become a true 3D map of the surface of every planetary body within our solar system, the planets, moons and asteroids (as data becomes available through captured images), a whole host of such tours based on real captured data might well be possible within our children's lifetime.