I’ve just listened to an item on the BBC’s 6 O’Clock News about the mapping of dark matter using Hubble images. Within this item was a classic journalistic grabbing of the wrong end of the stick:

“Scientists shot a beam of light from the Hubble telescope and watched how it was bent (by the gravity of the dark matter).”

Of course, what the astronomers actually did was to examine the images of light sent out by the very distant objects and then modelled what shape of dark matter would generate those distortions. Part of this modelling would probably have been to run simulations involving ray tracing back along the line of sight with different configurations of dark matter. THis is probably what confused the poor journalist who probably had a media studies degree and no idea about astronomy or science in general.