Related by context. Frequent words. (Click for all words.) 59 spectra 56 active galactic nuclei 56 X ray emission 56 photoluminescence 56 redshifts 54 diffraction pattern 54 solar corona 54 spectroscopic 53 Hubble observations 53 coronal 53 Cepheids 52 supernova remnants 52 XMM Newton 52 elliptical galaxies 52 planetary nebulae 51 elemental composition 51 photometer 51 radial velocity 51 interferometry 51 galaxy formation 51 gravitational lens 51 GRBs 51 morphologies 51 magnetars 51 gravitational lensing 51 interferometric 51 galaxy clusters 50 isotopic composition 50 Galaxy Evolution 50 heavily cratered 50 photometric 50 optical wavelengths 50 Type Ia supernovae 50 novae 50 Gamma rays 50 ultraviolet wavelengths 50 gamma rays 49 photometry 49 anisotropy 49 Gamma ray bursts 49 supernova remnant 49 Computed tomography 49 accretion disk 49 interferometers 49 protostar 49 spectrometry 49 Crab Nebula 49 Orion Nebula 49 VIRTIS 48 fluorescing 48 near infrared NIR 48 redshift 48 frequency comb 48 fluorophores 48 isotropic 48 absorbance 48 tropospheric 48 Cosmologists 48 infrared wavelengths 48 Carina Nebula 48 isotope ratios 48 quasar 48 supernova explosion 48 Keck telescope 48 scanning electron microscopy 48 irradiance 48 transmission electron microscopy 48 galaxy NGC 48 nanobubbles 48 VLBA 48 spectrographs 47 astronomical objects 47 amplitudes 47 spectroscopy 47 X ray beam 47 anisotropic 47 noctilucent clouds 47 crystallographic 47 nanosized 47 numerical simulations 47 abundances 47 gamma ray bursts 47 WASP #b 47 Doppler ultrasound 47 X ray 47 protoplanetary disk 47 nebulas 47 optical microscopy 46 keV 46 quasars 46 detectability 46 superlens 46 noble gases 46 z = 46 transmission electron microscope 46 gamma ray 46 shorter wavelengths 46 galaxy cluster 46 Eta Carinae 46 distant galaxies 46 laser pulses