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Wind Rider Pathfinder Mission to Trappist-1 Solar Gravitational Lens Focal Region in 8 Years
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  • Brent Freeze,
  • Jeff Greason,
  • Michel Lamontagne,
  • Darrel Conway,
  • John Fuller,
  • Ronnie Nader,
  • Eric Davis,
  • Jason Cassibry,
  • Stephanie Thomas,
  • Jaime Jaramillo Febres,
  • Adolfo Chaves-Jiménez
Brent Freeze
American Institute of Aeronautics and Astronautics (AIAA), Nuclear and Future Flight Propulsion (NFFP) Technical Committee, Practical Interplanetary Propulsion (PIP) Group

Corresponding Author:[email protected]

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Jeff Greason
Electric Sky
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Michel Lamontagne
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Darrel Conway
Thinking Systems Inc.
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John Fuller
Virgin Orbit
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Ronnie Nader
Ecuadorian Space Agency
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Eric Davis
Baylor University
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Jason Cassibry
University of Alabama in Huntsville
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Stephanie Thomas
Princeton Satellite Systems
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Jaime Jaramillo Febres
Ecuadorian Space Agency
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Adolfo Chaves-Jiménez
Costa Rica Institute of Technology
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A key benefit to the scientific community of a pathfinder to 542 AU is calibration data for an array of instruments on a flagship probe to interstellar space. There are fundamental processes and parameters of the near interstellar medium, whose estimated range of values could be greatly narrowed by in-situ sampling from a fast and small mission. By selecting an angle relative to the sun, plane of the ecliptic and a scientifically interesting target (such as Trappist-1), it is possible to perform initial optical measurements from the Solar Gravitational Lens (SGL) focal region on the same pathfinder. Doing so provides a basic set of data for larger follow-on missions to observe that (and other) solar systems in greater detail. By combining the datasets from 2 solar cycles (22 years) of space weather monitoring satellites, Voyager 1 and other deep space probes, the Practical Interplanetary Propulsion (PIP) Study constructed a radial profile for the solar wind ranging from 1 AU through the foreshock at 83 AU, to a notional heliopause at 123 AU, and the near interstellar medium out to 1,800 AU. The resulting matrix of plasma parameters was applied to a trajectory model “seed code,” to test flight paths for future probes. This paper presents an example pathfinder, consisting of a cubesat bus equipped with a Wind Rider propulsion system and radioisotope power system (RPS). A brief description of those subsystems and how they interact with the solar wind or interstellar medium is included. Trajectory simulation results estimate the trip time from 1 to 542 AU near the plane of the ecliptic takes 6.9 years. Adding a compact imaging instrument enables the probe to sample data from the vantage point of the Trappist-1 SGL, as well as PickUp Ions (PUI) for a 1 year science campaign. Total pathfinder mission time after launch is less than 8 years. A set of policy-making recommendations for enabling such small precursor-type missions is provided in the conclusions, as well as ways to extend the mission to communicate from 1,000 AU to 1,800 AU. Alternatively, a method to gradually decelerate to a near stop at the end of the mission, using the Wind Rider to drag against the interstellar plasma, is also included.