Google Earth Imagery Update: Strange image in the Sahara

Google has recently pushed out another imagery update. We created maps for March, April and May imagery, but did not find any significant changes in the March and April maps since the last update a week ago. There is, however, quite a lot of new May imagery.


May imagery. Red: Recently added imagery. Blue: imagery as of May 29th.

To find the locations in Google Earth download this KML file.

We haven’t been able to find any major events captured in the new imagery, but we did come across a strange image in the Sahara. It is in the south of Algeria and covers an area that has not previously been imaged with high resolution imagery.

We can see nothing of particular interest in the imagery, with half of the area being obscured by clouds, and no distinguishable features on the ground. Although it is hard to judge resolution, we think it is lower resolution than the nearby DigitalGlobe image. At first sight it appears to consist of three parallel strips, but the clouds all line up which would not be the case if it was three consecutive passes of a satellite, so we suspect it is all one image or three images captured in one pass. It also has no attribution (the NASA attribution is for the very low resolution background image).

Or first guess is a low altitude, relatively low resolution satellite, such as are used by Google’s own Terra Bella (formerly Skybox Imaging) and Planet Labs.

The strips are at a different angle from most satellite imagery which tends to be nearly aligned in a north-south direction. Strips of other alignments do exist but we believe they are typically for newly launched satellites that have not yet moved to a polar orbit. Near polar orbits tend to be preferred as it provides greater coverage. We do not know if this is the case for companies like Planet Labs which has large numbers of satellites.

If any of our readers know anything more about the origin of this imagery, please let us know in the comments.

Find it in Google Earth with this KML file.

About Timothy Whitehead

Timothy has been using Google Earth since 2004 when it was still called Keyhole before it was renamed Google Earth in 2005 and has been a huge fan ever since. He is a programmer working for Red Wing Aerobatx and lives in Cape Town, South Africa.



Comments

  1. Daniel Plant says:

    Could this be from TeLEOS-1, Singapore’s first commercial Earth Observation satellite? It’s in Near Equatorial Orbit (NEqO)

  2. It looks like this image was indeed acquired by one of Terra Bella┬┤s Skysats.
    Skysats have 3 detectors arranged exactly this way. This particular one is collected north of the sub-solar point, since detector 2 is lagging.

    Vasilis Kalogirou

    • Hill Penfold says:

      I like your interpretation. As to why this imagery is included, I don’t know. As an observer of Google Earth imagery since late 2004, before Keyhole was acquired by Google, it may just be a “mistake”. Much more frequently in the past various patches were added to imagery that had no seeming reason for inclusion. Often it seems that a bundle of imagery was purchased and the random images were a part of it. With so much imagery being added it is unlikely that everything is analyzed – that’s for us satellite mapping fans to do.

  3. Thanks for sharing a great post!

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