Abstract
Abstract
We derive purely gravitational constraints on dark matter and cosmic neutrino profiles in
the solar system using asteroid (101955) Bennu. We focus on Bennu because of its extensive
tracking data and high-fidelity trajectory modeling resulting from the OSIRIS-REx mission. We find
that the local density of dark matter is bound by ρ
DM ≲ 3.3 × 10-15 kg/m3 ≃ 6 × 106 ρ̅DM, in the vicinity of ∼ 1.1 au (where ρ̅DM ≃ 0.3 GeV/cm3). We show that high-precision tracking data of solar
system objects can constrain cosmic neutrino overdensities relative to the Standard Model
prediction n̅ν, at the level of η ≡ n
ν/n̅ν ≲ 1.7 × 1011(0.1 eV/mν
) (Saturn), comparable to the existing bounds from KATRIN and other
previous laboratory experiments (with mν
the neutrino mass). These local bounds have
interesting implications for existing and future direct-detection experiments. Our constraints
apply to all dark matter candidates but are particularly meaningful for scenarios including solar
halos, stellar basins, and axion miniclusters, which predict overdensities in the solar
system. Furthermore, introducing a DM-SM long-range fifth force with a strength α̃D
times stronger than gravity, Bennu can set a constraint on ρ
DM ≲ ρ̅DM(6 × 106/α̃D). These constraints can be improved in the future
as the accuracy of tracking data improves, observational arcs increase, and more missions
visit asteroids.