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تسجيل مستخدم جديدA Dearth of Dark Matter in Ordinary Elliptical Galaxies
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The kinematics of the outer parts of three intermediate-luminosity elliptical galaxies have been studied using the Planetary Nebula Spectrograph. The galaxies velocity dispersion profiles are found to decline with radius; dynamical modeling of the data indicates the presence of little if any dark matter in these galaxies halos. This surprising result conflicts with findings in other galaxy types, and poses a challenge to current galaxy formation theories.
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