Aquila Field of Streams

The Aquila region of the Milky Way's halo contains a dense confluence of stellar streams, substructures, and overdensities — collectively termed the Field of Streams when its full extent across the northern SDSS footprint was mapped — whose density and geometric concentration are significantly higher than predicted by random accretion models. Multiple kinematically distinct streams intersect or overlap in this region, including wraps from the Sagittarius stream, the Orphan Stream, and several unnamed substructures, all converging near the Aquila overdensity itself. ΛCDM explains individual streams as disrupted satellites, but the concentration of multiple streams in a coherent region of the sky with overlapping angular momenta is statistically improbable under random infall and suggests a systematic organizing principle absent from the standard framework.

In Successive Collision Theory, the concentration of streams in the Aquila region is a direct consequence of angular momentum inheritance combined with the geometry of the collision debris field around the Milky Way. The initial pocket collision produced a debris field with angular momentum varying smoothly across the volume; material with specific angular momentum values in the range corresponding to the present-day Aquila direction formed satellite structures that orbit preferentially in that zone of phase space. As these structures are tidally disrupted by the Milky Way's gravitational field, their debris naturally deposits into the orbital plane defined by their inherited angular momentum — the same plane for all structures originating from the same angular momentum stratum. The Aquila region marks a convergence of the inherited angular momentum field's preferred infall direction, making it a focus for tidal debris from multiple progenitors that shared similar angular momentum at formation.

The nested comoving frame hierarchy further contributes by establishing a preferred large-scale tidal axis that focuses infalling material toward the same halo regions over multiple orbital periods. The gravitational superposition from parent frames enhances the effective tidal force along the collision axis, preferentially disrupting satellites whose orbits are aligned with this axis and depositing their streams along a corridor in the sky that is observed as the Aquila Field of Streams. This explanation naturally accounts for both the concentration of streams in the region and their kinematic variety: they come from different progenitors but share a common preferred orbital geometry set by the collision's angular momentum field.