[RantyDave]

Despite the haters, this is pretty much on the money. This is the light scattered from a single atom that came through the lens and hit exactly just one pixel on the sensor. That dot is (guessing) millions of times larger than an actual single atom.

[caf]

This is no different in principle than a photo of a starry night sky, where the size of the pixel is far greater than the actual angular size of the object from our vantage point.

[effie]

Take a zoom at the original picture. It's 4 pixels.