SIMBAD references

We tentatively look at anthropic constraints on the cosmological constant (CC) Λ at galactic scales by investigating its influence on the motion of the Sun throughout the Milky Way (MW) for -4.5 ≤ t ≤ 0 Gyr. In particular, we look at the Galactocentric distance to which the Sun is displaced at the end of the numerical integration of its equations of motion modified in order to include the effect of Λ. Values of Λ placing our star at its birth more than 10kpc from the Galactic Centre (GC) are to be considered implausible, according to current views on the Galactic Habitable Zone (GHZ) on the metallicity level needed for the formation of stars. Values yielding approaches too close to the GC should also be excluded because of the risks to the evolution of life from too many nearby supernova explosions and gamma-ray bursts. We investigate the impact on our results of the uncertainties in both the MW model parameters and the Sun's initial conditions, in particular in the Hubble parameter H₀ and the local standard of rest speed Θ₀, accurate at levels of 2 and 6.2 per cent, respectively. Whereas H₀ = 70.1km/s/Mpc,Θ₀= 254km/s and Λ ≤ 10^–55/cm2 locate the place of birth of the Sun at 19.6kpc from the GC, the same values for H₀ and Λ, and Θ^max₀= 270km/s place it at the plausible Galactocentric distance of 8.5kpc. Λ = 10^–54/cm2 and Λ = 10^–53/cm2 place the Sun at 10.6kpc and 18.7kpc, respectively.