Dark Matter is stuff we know has to be out there to explain things like the stars orbitting too fast in galaxies and light bending in strange ways.
But it is matter we cannot see using any of the wavelengths of the Electromagnetic Spectrum. So it is Dark!
Dark Matter (along with Dark Energy) make up a large proportion of the Universe – so if anyone tells you Scientists think they know everything just tell them Scientists KNOW we don’t know even half of the Universe!!
Anyway – this article in Wired reckons that Dark Matter particles might be collecting in our Sun.