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We present the result of an extensive search for non-axisymmetric structuresin the dwarf satellite galaxy of M81: NGC 2976, using multiwavelength archivalobservations. The galaxy is known to present kinematic evidence for abysimmetric distortion, anyhow the stellar bar presence is controversial, dueto the possible interpretation of NGC 2976 presenting an elliptical disktriggered by a prolate dark matter halo. We applied diagnostics in order todetect stellar bars or spiral arms. The m=2 fourier phase has a jump around 60arcsecs consistent with a central bar and bisymmetric arms. The CO, 3.6 $\mu$surface brightness and the dust lanes are consistent with a gas rich centralbar and possibly with gaseous spiral arms. The kinematic jumps related with thedust lanes suggest that the bar perturbation in the disk kinematics isnon-negligible and the reported non-circular motions, the central gas excessand the nuclear X-ray source (AGN/Starburst) might be produced by the centralbar. SPH simulations of disks inside triaxial dark halos suggest that the twosymmetric spots at 130 arcsecs and the narrow arms may be produced by gas atturning points in an elliptical disk, alternatively the potential ellipticitycan be originated by tidally induced strong stellar bar/arms. We conclude that,the gas rich bar and spiral arms triggered by tidal stirring, and primordialhalo triaxiality, can explain most of the non-circular motions, massredistribution and nuclear activity. Distinguishing between them requiresdetailed modeling of environmental effects. An analysis similar to this mayreveal such kind of structures in other nearby dwarf satellite galaxies, and ifconfirmed, the same evolutionary scenario will be applicable to them. Thisimplies biases constraining their dark matter distribution and also makingcomparison against theoretical predictions for isolated galaxies.

Non-Axisymmetric Structure in the Satellite Dwarf Galaxy NGC2976: Implications for its Dark/Bright Mass Distribution and Evolution