A Manned Flyby Mission to Eros

Eros (433), the largest of the known close approach asteroids, will pass within 0.15 AU of the Earth during its 1975 opposition. This close approach, occurring near the asteroid\u27s descending node and perihelion, offers an early opportunity for a relatively low energy manned interplanetary mission. Such a mission could provide data important to the space technologies, to the astro sciences, and to the utilization of extraterrestrial resources. Mars and Venus are the primary targets of early manned planetary flight, and therefore early manned planetary missions to other objects should support or complement the Mars and Venus programs. The model mission described in this paper satisfies this criterion and can be accomplished by a single uprated Saturn V and derivatives of MORL and Apollo. The model mission includes a 527-day free return flight performed by a 330,000-pound vehicle system. An S-IVB/IU stage injects the spacecraft into a twoday geocentric ellipse where it is erected to its interplanetary configuration. The spacecraft departs with a second impulse and 270 days later passes within 50 miles of Eros where a turret-mounted instrument complex and an unmanned probe make a careful examination of the asteroid\u27s surface. About 257 days later the reentry vehicle, a six-man Apollo-type command module separates from the spacecraft and returns the crew to the Earth\u27s surface. The mission is concluded to be technically feasible and an attractive complement to the manned interplanetary program