Coronal Mass Ejections Recorded by Film
by, 03-08-2012 at 07:18 PM (1348 Views)
Those who take interest in solar flares have been entertained quite a lot over the past few years. Coronal Mass Ejections (CMEs) from our Sun hurl massive amounts of charged garbage out into space. The first CME was "seen" by a satellite put up by the lab where I work, with a very primitive pixelated camera that sent a digitized signal to Earth and produced an image on Polaroid film. Perhaps some of the first "hybrid" photography!
More recent images of these CMEs (see the attached image) are full of detail. The CMEs are even more impressive when you consider their scale: they can protrude from the surface of the sun by many times the diameter of Earth.
The CMEs send charged particles out into space, and some of it comes towards us and makes it past our protective magnetosphere. The charged particles create auroral activity, which is now forecast on a regular basis:
In addition to creating auroras, the ejections can affect electronic equipment on Earth. Since we earthlings are becoming ever more dependent on electronica, there is growing interest in "space weather." In the past, CMEs have knocked down power grids, disrupted cell and GPS communications, blacked out radio, etc. As I write this, it is apparent that US cities from Chicago northward might see auroras tonight; blackouts are deemed unlikely this time, but chances are good that there are many more CMEs to come in this latest cycle of high activity.
In addition to worrying electronics experts, what these CMEs do is contribute to the fog in our film. Photographic film is a pretty good radiation dosimeter; I used to wear a film badge when I worked in a nuclear lab in college. It's hard to say how much the contribution to base fog will be- that depends on the location of the film and what sensitizers are present. Offhand I would guess that Kodak HIE (RIP!) would be particularly susceptible.
I wonder what creative uses of radiation fog might be possible...