iPhone 5
ƒ/2.4
4.12 mm
1/120
80

On the way to Half Moon Bay, I was tooling around with the satellite view, and noticed a large plane in motion.

The imager in this sat-cam uses a linear-CCD in push broom mode (so it has a separate 1D sensor for each color, relying on the precise orbital scanning speed like a scanner) rather than the 2D image sensor in most digital cameras. So the R, G and B sensors are sampling any particular spot at a slightly different time. For most things this doesn’t matter, but for fast moving things, you get a spectral blur…

It’s almost a reverse-doppler shift to hyperspectral aerospace… =) Close-up view below…

12 responses to “Caught by Satellite”

  1. Different sensor types:
    Jensen_RSE_7_3

  2. I bet it’d be possible to calculate the speed of the plane…

  3. [http://www.flickr.com/photos/andyi] Possible, but tricky without knowing more about the orbital velocity of the satellite. You could also calculate the altitude of the plane.

  4. There’s an entire group on Google forums that dedicates itself to finding satellite images of captured aircraft.

    It’s actually kind of fun, if you don’t mind scanning for hours. I’ve found a few myself that hadn’t been documented before.

  5. Or, finding satellite trackers by aircraft…

    Contact

    [http://www.flickr.com/photos/andyi] and [http://www.flickr.com/photos/jhapeman] — You could analyze the foliage and if the imagery appears to be at the 50cm legal limit for civilian sats (but probably closer to the more affordable 1 meter resolution), and knowing who Google buys from, you could deduce the orbital altitude, which give you the scanner speed. Each of R,G,B is already registered to a fixed ground point, so the orbital inclination (i.e., angle of passage at this latitude) and rotation of Earth can be ignored, and each color band on the plane is captured by a successive linear sensor overhead. Knowing the wing width for this plane, you can calculate the inter-band distance. We are nearly over the plane, so the angular calculations are easier… and its altitude relative to the ground (on approach to SFO) is a small correction to the inter-object distance estimate….

  6. I pulled it up on my Mac and zoomed in… Looks pretty cool. You can even see the turbulent thermal trails from the engines

    United Flight over Pilarcitos Lake

    Is that 4th-band, looking like an outline, near-IR?

  7. super!
    this is what my father has been doing from 1973 – satellite photogrammetry 🙂

  8. Excellent — love the near-IR aircraft outline!

  9. Is the battery indicator in the upper-left of the display showing vehicle charge?

  10. [http://www.flickr.com/photos/brentdanley] – yes, and there is a more informative display in the center console with range (and you can display a graph of all kinds of battery information if you want max info)

  11. [http://www.flickr.com/photos/jurvetson] Thanks. Are there popups at 20% and 10% like in iOS? 😉

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