An examination of an interstellar hypothesis for the source of comets

The Sun's gravity tends to pull in nearby an excess of low-energy particles, as compared with the distribution of energies at infinity. The size of this effect is calculated in an attempt to determine if it is large enough to lend support to the hypothesis of an interstellar origin for comets. The effect appears to be too small; the greatest possible reduction of observed mean energy below intrinsic mean energy is a factor $\text{1}\text{2}$, if the true velocity distribution of the particles (comets) at infinity is Maxwellian. Non-Maxwellian distributions, however, could violate this restriction.