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I recently noticed this odd dust formation on my gaming console's camera peripheral. The dust is significantly thicker on the right side, with the television in the background. On the left, with a West-facing window in the background, there is very little dust. I did not touch the peripheral since last dusting the entire thing. What caused this formation? Have any of you witnessed a similar phenomenon?

I have a guess, but I'm not convinced. For about one hour each night, as the sun sets, the left side receives direct sunlight, and the right is blocked by the TV, pretty much as the dust-made line represents. This sunlight heats up the black casing, which induces convection preventing dust from falling on the hotter, sunlit part of the thing.

I wouldn't expect this to cause such a disparity, though. Even an all-day effect doesn't quite make sense, because we leave the blinds closed during the day. The only way I can see such a disparity occurring is if the heating of the casing not only prevents dust from settling, but can remove settled dust, leaving a nearly dustless surface on the left, with many times more on the shadowed right.

Edit: To those suggesting charge has built up on the sun-exposed side, how would such a charge prevent dust from collecting? Am I mistaken to assume that a charged surface could only attract dust (and not repel it)?

Note: With a teacher home for the summer in the apartment, the TV seen in the picture has been on for at least 8 hours a day. I'm not sure this has any effect, but it might rule others out.

dust on electronics

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    $\begingroup$ It potentially could; if that side is hot then it will probably create a convective air current up (because hot air rises) and even a weak air current would make it significantly harder for dust to settle on it, since dust is mostly just carried with the breeze. However it's pretty hard to say definitively without further experimentation: for example, if you shine a bright light on the other side, does it also stop dust from collecting on the surface. $\endgroup$
    – CR Drost
    Commented Aug 4, 2015 at 22:03
  • $\begingroup$ what if charge builds up on the sunlit part as a consequence of light stripping off some electrons? $\endgroup$
    – Phoenix87
    Commented Aug 4, 2015 at 22:18
  • $\begingroup$ Indeed, charging seems the more likely cause to me. $\endgroup$
    – Jon Custer
    Commented Aug 4, 2015 at 22:26
  • $\begingroup$ How would charging reduce the amount of dust? Couldn't it increase the amount of dust, attracting the particles by polarization? $\endgroup$
    – Sam
    Commented Aug 5, 2015 at 0:12
  • $\begingroup$ To reduce dust attached via electrostatic charge one needs to neutralize the charge. This is often done by introducing both positive and negative ions and letting them combine with the surface ions. While it's possible that sunlight could ionize the air, producing a similar effect, I believe it would be the UV portion that would be largely responsible for this ionization. Since the sunlight came through a pane of glass, it's likely that most of UV radiation was filtered out, making this explanation unlikely. $\endgroup$
    – Eph
    Commented Aug 27, 2015 at 14:37

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Thermophoresis

A temperature gradient induces a force on small particles due to uneven kinetic energy transfers. This processes is called thermophoresis. The hot plastic will create a strong temperature gradient in the air directly above the plastic, forcing particles away from the plastic and allowing them to be entrained in the convective flow also due to the high temperature.

This certainly will prevent particles from landing on a hot surface. It should also be able to remove dust particles that are not too strongly attached via van der waals forces.

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