Gaia spacecraft reveals dwarf galaxies unaffected by dark matter

Recent data from the Gaia spacecraft challenge long-held beliefs about the nature and composition of dwarf galaxies, suggesting that they are more transitory and less affected by dark matter than previously thought.

In contrast to old popular beliefs, a recent study has discovered evidence that suggests the majority of dwarf galaxies may actually be annihilated shortly after entering the Galactic halo. 

An international team has recently shown that dwarf galaxies may be out of equilibrium according to the most recent catalogue from ESA's Gaia spacecraft. 

The findings raise significant doubts about the traditional cosmological model, especially regarding the abundance of dark matter in the closest surroundings.

The dwarf galaxies surrounding the Milky Way have long been thought to be old satellites that have been circling our galaxy for almost 10 billion years.

This meant that in order to shield them from the tremendous tidal forces brought on by our galaxy's gravitational pull, they had to be extremely dense in dark matter. 

The significant variations in star velocities inside these dwarf galaxies were also thought to be driven by dark matter.

Remarkably, most dwarf galaxies have orbitals that are significantly larger than the Sagittarius dwarf galaxy, which entered the halo 5–6 billion years ago. This suggests that the majority of dwarf galaxies are quite new, having formed less than three billion years ago.