Building an Autonomous Spacecraft

In a 1990 NASA press conference, Carl Sagan proclaimed that humanity had completed an initial exploration of our solar system. While missions have successfully reached Mars, Venus, and the moons of Saturn, the full potential of autonomous space probes remains untapped. For instance, the rovers Spirit and Opportunity relied on pre-planned commands, limited by the Martian landscape they observed the previous day.

When deploying a probe to a planet light-years away, communication delays render real-time navigation from Earth impractical. Thus, an interstellar probe must independently identify and investigate its environment. Researchers Steve Chien and Kiri L. Wagstaff from the Jet Propulsion Laboratory addressed this challenge in a 2017 publication.

They propose the possibility of exploring a Europa-like exoplanet, which would necessitate drilling through thick layers of ice. “Once the ice is penetrated, a submarine designed for life detection would have to explore for extensive periods” (Chien & Wagstaff, 2017, p. 2). This autonomous adaptation presents a significant hurdle, but existing techniques may facilitate this task.

Historically, methods for detecting surface features from interplanetary probes have been suggested, yet they remain largely untested. In pursuit of extraterrestrial life, NASA has begun experimenting with autonomous instruments capable of life detection. Recently, a drill intended for microbial search on Mars was developed for autonomous operation and trialed on Earth. This technology is being refined for future Mars rover missions.

Video Description: This video explores the methods and technologies used in the search for life on exoplanets, including the role of autonomous spacecraft.

An Ambassador to the Stars

Upon discovering life on a distant planet, one of the significant challenges would be to understand and potentially communicate with it. In a 1960 paper, a Stanford University professor suggested that future missions could detect life by searching for advanced technology, such as "radio communication" (Bracewell, 1960, p. 670). While intriguing, this perspective assumes that all intelligent civilizations will evolve similarly to ours, which may not be the case.

An interstellar probe must, therefore, devise its own methods for conducting scientific inquiries. Stephen Baxter from the British Interplanetary Society and researcher Andreas M. Hein envision a specialized probe that can autonomously conduct scientific experiments, formulate hypotheses, and design data collection procedures (Hein & Baxter, 2018, p. 20). This capability would be crucial for uncovering previously unknown forms of life.

The intelligent probe Baxter and Hein describe would allow researchers to avoid limiting their understanding of life based on terrestrial experiences. Identifying life on an exoplanet is one challenge; establishing meaningful communication with an alien civilization is another, as messages may become obscured without a shared context.

One potential solution might involve pictographs that convey meaning in a universally interpretable format. This strategy builds on earlier communication efforts, like the plaque on the Pioneer 10 spacecraft. Effectively interpreting messages from extraterrestrial life may necessitate human involvement, as creating machines capable of decoding alien communication could be overly ambitious for the foreseeable future.

Rather than acting solely as translators, interstellar probes may focus on analyzing potential threats posed by alien civilizations. Hein and Baxter suggest that 'game theory' could be applied to assess the nature of encountered beings (Hein & Baxter, 2018, p. 17). Much like diplomats in foreign lands, our cosmic envoy would provide insights into the behaviors of intelligent extraterrestrials, leaving the translation task to us.

A Replicating or Adaptive Interstellar Probe?

Another intriguing feature of an autonomous spacecraft could be its ability to replicate itself. Proposed in 1966 by mathematician John von Neumann, this concept involves extracting resources from distant planets to create additional probes. These probes would replicate and adapt their designs to explore diverse environmental conditions across various worlds.

However, resource extraction from distant planets could convey a hostile message to nearby intelligent life. This approach also raises ethical concerns, as it parallels colonialism on Earth. Carl Sagan and William I. Newman highlighted potential issues related to self-replicating interstellar crafts in their 1983 paper.

For instance, intelligent beings encountering such a probe might view it as a threat. The uncontrolled spread of replicating machines throughout the galaxy could endanger life on distant exoplanets, as aliens might perceive the machines as a risk to their existence. Science fiction often illustrates the destructive potential of unchecked replicating technologies.

While replication is an appealing feature, it may be more prudent to consider how interstellar probes can adapt their designs without replicating. NASA is currently exploring this concept for an upcoming mission to Saturn’s moons, employing mini robots known as shapeshifters that can both fly and traverse the surface of distant celestial bodies. A self-morphing design would not rely on specific resources that may be scarce on exoplanets.

As we venture into our galaxy, it is essential to learn from Earth's history, particularly regarding colonialism and conservation. Initiating our exploration of the cosmos in a perceived aggressive manner could lead intelligent extraterrestrials to view us as ethically unprepared explorers.

Video Description: This video discusses the James Webb Space Telescope's groundbreaking findings related to habitable worlds and potential signs of life in our solar system.

If you enjoyed this exploration, check out my other article on methods for detecting alien spacecraft traveling near the speed of light. Click here.