Ultra diffuse galaxy

[15][16] The lack of X-ray emissions from the galaxy and surrounding area also show that the number of globular clusters can not be as many as was claimed before.

[17] In 2018, the same authors reported the discovery that the ultra diffuse galaxy NGC 1052-DF2[b] is dark matter-free, based on velocity measurements of its ~10 globular cluster system.

[21] However, this conclusion relies heavily on the galaxy having a moderate inclination of 32° between disc and sky planes, which is estimated from the somewhat oval appearance.

Using detailed simulations of AGC 114905 in the alternative gravity theory known as Modified Newtonian Dynamics, it was shown that a disc galaxy with its properties can appear slightly oval even if viewed face-on due to disc self-gravity, in which case the rotation curve could be much higher and the galaxy could be quite consistent with theoretical expectations.

[22] An overestimated inclination is unlikely if galaxies are dominated by dark matter because then the disc is not self-gravitating, so it should be close to circular when viewed face-on.