The suggested options for sending a spacecraft to ʻOumuamua within a time-frame of 5 to 10 years are based on using first a Jupiter flyby followed by a close solar flyby at 3 solar radii in order to take advantage of the Oberth effect or more advanced options such as a solar sail and a laser sail.
Detail
ʻOumuamua was at first thought to be traveling too fast for any existing spacecraft to reach. The Initiative for Interstellar Studies launched Project Lyra to assess the feasibility of a mission to ʻOumuamua. Several options for sending a spacecraft to ʻOumuamua within a time-frame of 5 to 25 years were suggested. The challenge is to get to the asteroid in a reasonable amount of time, and yet be able to gain useful scientific information. To do this, decelerating the spacecraft at ʻOumuamua would be "highly desirable, due to the minimal science return from a hyper-velocity encounter". If the investigative craft goes too fast, it would not be able to get into orbit or land on the asteroid and would fly past it. The authors conclude that, although challenging, an encounter mission would be feasible using near-term technology. Seligman and Laughlin adopt a complementary approach to the Lyra study but also conclude that such missions, though challenging to mount, are both feasible and scientifically attractive. One option is using first a Jupiter flyby followed by a close solar flyby at in order to take advantage of the Oberth effect. Different mission durations and their velocity requirements were explored with respect to the launch date, assuming direct impulsive transfer to the intercept trajectory. A spacecraft with a mass of tens of kilograms using a heat shield like that in the Parker Solar Probe and a Falcon Heavy-class launcher with a trajectory including a powered Jupiter flyby and a solar Oberth maneuver could reach 1I/ʻOumuamua if launched in 2021. More advanced options of using solar, laser electric, and laser sail propulsion, based on Breakthrough Starshot technology, have also been considered.
