Hitchhiker is a concept under development to use a tether (essentially, a cable) to extract orbital energy from natural bodies and use it to accelerate a spacecraft. It would replace the need for chemical rockets and other propulsion systems in which momentum is ejected to gain thrust.

Caption: The Hitchhiker uses a tether to attach to a natural body, swings around the body while controling the tension in the tether, then severs the tether to slingshot off to a target body. The tether is used to extract orbital energy from the natural body to accelerate the spacecraft. The tether is barely visible in this artist's rendition. [Click on the image to see a larger version]


Applications include asteroid hopper missions, in which the tether is used to move from asteroid to asteroid with little or no fuel expenditure. Missions to the outer solar system (Kuiper belt) could also be envisaged in which a tether is used to deflect or stop a spacecraft, thereby enabling long duration missions to multiple objects.

Challenges include tether design, TAD (tether-attachment device) design, braking mechanism, energy harvesting mechanism (we use the tether brake to generate and store energy onboard the spacecraft).

Principal Investigator is Masahiro Ono (JPL). Other investigators and contributors are Marco Quadrelli, Gregory Lantoine, Paul Backs, Chen-Wan Yen, Alejandro Lopez-Ortega, John Gallon, Magdy Bareh and me.

Funded by the NASA Innovative Advanced Concepts program (NAIC)

David Jewitt

Comet Jewitt Kuiper