Catching 3I/ATLAS Using a Solar Oberth

ADAM HIBBERDT. MARSHALL EUBANKS (Space Initiatives Inc, Princeton, WV 24740, USA), ANDREAS M. HEIN (SnT, University of Luxembourg, L-4365, Luxembourg)

2026.079.0131

DOI https://doi.org/10.59332/jbis-079-04-0131

The third interstellar object to be discovered, 3I/ATLAS, has a unique and continually unfolding story to tell of its nature and origin as it is monitored by telescopes on Earth and in space. Previous research into missions using chemical propulsion have addressed the direct case, where the opportunity to launch already expired before 3I/ATLAS’s discovery. In contrast, investigations herein exploit ’Optimum Interplanetary Trajectory Software’ to simulate an indirect option for chemical propulsion, namely the Solar Oberth Manoeuvre (SOM). Thus, a low perihelion burn provides maximum benefit from the Oberth Effect, accelerating the spacecraft rapidly towards the receding 3I/ATLAS. Though in principle feasible, results indicate this presents significant challenges. For launch years between 2031 and 2037 inclusive, a 2035 launch permits the most efficient transfer to 3I/ATLAS. The reference mission requires a SOM at 3.2 Solar Radii from the Sun’s centre, with an intercept after 35-50 years. We find the SOM can leverage spacecraft masses up to ~500 kg. Two or three solid boosters could deliver the required SOM ∆V, whilst a refuelled Starship Block 3 in LEO has sufficient performance for such a mission. Also with a SOM, some of the payload mass would be needed for a heat shield to protect against the high solar flux at low perihelion..

Keywords: Keywords: 3I/ATLAS, Solar Oberth Maneuver, Interstellar Objects, Chemical Propulsion, Mission Architecture