At many points along this journey, we seek or get guidance from well-meaning peers, friends, family, and loved ones who advise us what we should desire and what we should avoid.

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Friends who have known each other for decades, or siblings who get along well and are comfortable spending long periods of time with one another, would also be suitable for this sort of situation, said Jason Kring, assistant professor at Embry-Riddle Aeronautical University, who is not involved with the mission.

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