This is because the dark matter can only interact gravitationally, and thus will not dissipate.

After they are formed, the stars in the globular cluster begin to interact gravitationally with each other.

The above prediction, that all forms of energy interact gravitationally, has been subject to experimental tests.

Earth gravitationally interacts with other objects in space, especially the Sun and the Moon.

These polar rings are thought to form when two galaxies gravitationally interact with each other.

This measurement was interpreted to mean that unseen matter at the core is interacting gravitationally with nearby stars.

However, there are several hypotheses about how antimatter gravitationally interacts with normal matter:

Dark matter, which would interact gravitationally but not electromagnetically, would account for the discrepancy.

Although the galaxies were previously thought to be interacting gravitationally, the newer Hubble image shows little evidence for this.

M82 is a galaxy that is interacting gravitationally with M81.