Related by context. Frequent words. (Click for all words.) 66 filaments 63 electron density 62 threadlike 62 protoplanetary disk 61 electrically conducting 60 manganese oxide 60 planetary nebulae 60 silicon atoms 60 torus 60 filament 59 ionized gas 59 anisotropy 59 ejecta 59 accretion disk 59 haloes 59 ionised 58 Ultraviolet light 58 metastable 58 cirrus 58 nitrogen atoms 58 nanosized 58 dye molecules 58 striations 58 crystal lattice 58 aragonite 58 photoluminescence 58 nanoscopic 57 ultraviolet wavelengths 57 microstructures 57 morphologies 57 porphyrin 57 fluorescing 57 nuclei 57 active galactic nuclei 57 fluoresces 57 planetary nebula 57 collagen fibers 57 X ray emission 57 aerosol particles 57 interstellar medium 57 calcite 57 protostar 57 exciton 57 crystalline structure 57 dipoles 57 radially 57 mycelium 57 chromophore 57 solar nebula 57 excitons 56 Cepheids 56 γ 56 tubules 56 isotropic 56 silicates 56 optical wavelengths 56 nanometer sized 56 SWNTs 56 agglomerates 56 galaxy cluster 56 galaxy clusters 56 solar corona 56 nucleation 56 organic inorganic 56 magnetic fields 56 iron oxides 55 lithosphere 55 excitations 55 Hawking radiation 55 moonlets 55 magnetic flux 55 porphyrins 55 elemental composition 55 hydrocarbon molecules 55 visible wavelengths 55 superfluid 55 globular 55 galaxy NGC 55 noctilucent clouds 55 fluorescent probes 55 iridescence 55 vortices 55 terahertz radiation 55 gravitational lensing 55 electron spins 55 atoms 55 spinel 55 ionize 55 dimer 55 filamentous 55 waxy substance 55 Fig. 1A 55 dopant 55 nanocrystalline 55 toroidal 55 spacetime 55 spiral galaxies 55 planetesimals 55 dopants 55 shorter wavelengths 55 actin filaments