Introducing Humans to the Extraterrestrials: the Pioneering Missions of the Pioneer and Voyager Probes

This article gives a brief overview of how human life is represented on the 1972 Pioneer 10 and 1973 Pioneer 11 plaques and on the 1977 Voyager 1 and 2 Golden Records, sent on their journeys to deep space by the U.S. National Aeronautics Space Administration (NASA). Having left the boundaries of the Solar System and moving through interstellar space, the space probes still carry messages with information about their makers and their era. After a description of the two famous American interstellar messages, this article gives a basic introduction to their contents using some of the photographs available in the public domain. The overview includes the visual and audio part of the Voyager message and is focused around the questions for what types of information were included, what methods were used to communicate the information and how were humans introduced to the unknown receiver.

Deep space explorers: The Cultural Legacy and Historical Memory of Pioneer 10 and 11 and Voyager 1 and 2, from the Pale Blue Dot to SNL

Pioneer 10 and 11 and Voyager 1 and 2 have the distinction of being the only human-made objects to have left or be on track to leave the Solar System (other than the recently launched New Horizons mission). While their scientific work is significant, the history of these four missions reveals a deeper cultural legacy. One of the primary public faces of these missions was science communicator Carl Sagan. By exploring how Sagan defined the significance of these missions in his work, we reveal the impact of these missions on our collective imaginings of spaceflight and space exploration (i.e. “astroculture”). We find that the twin Pioneers and Voyagers inspired self-reflexive ideas of human isolation and fragility within the cosmos, introduced communication with extraterrestrials as a serious aspect of spaceflight efforts, and supplemented the image of the astronaut with the robotic probe as the symbol of the human spirit of exploration.

Remark on ``Indication, from Pioneer 10/11, Galileo, and Ulysses Data, of an Apparent Anomalous, Weak, Long-Range Acceleration''

Recently, Anderson et al. presented possible evidence for an anomalous acceleration acting on spacecrafts. Furthermore, the motions of several planets and comets are known to experience unexplained disturbances. A transneptunian comet or asteroid belt might be the common origin of these anomalies.

To Boldly Go …

The Breakthrough Starshot project was launched in 2016 with the aim of developing the technology to send robot spacecraft to the nearest stars. The first spacecraft to head out of the Solar System were launched in the 1970s. Pioneer 10 carries a plaque offering information about Earth and its inhabitants to any alien species that might one day intercept the craft. The Breakthrough Starshot panel included Stephen Hawking and Freeman Dyson. The idea is to use banks of lasers to accelerate mini robot craft to one-fifth of the speed of light with the aim of reaching the Alpha Centauri system within about twenty years.

Jovian electrons in the inner heliosphere

Context. Since the Pioneer 10 flyby of Jupiter it has become well known that electrons of Jovian origin dominate the lower MeV range of charged energetic particles in the inner heliosphere. Aims. Because the Jovian source can be treated as point-like in numerical models, many attempts to investigate charged particle transport in the inner heliosphere have utilized Jovian electrons as test particles. The reliability of the derived parameters for convective and diffusive transport processes are therefore highly dependent on an accurate estimation of the Jovian source spectrum. In this study we aim to provide such an estimation. Methods. In this study we have proposed a new electron source spectrum, specified at the boundary of the Jovian magnetosphere, fitted to flyby measurements by Pioneer 10 and Ulysses, with a spectral shape also in agreement with measurements at Earth’s orbit by Ulysses, Voyager 1, ISEE and SOHO. Results. The proposed spectrum is consistent with all previous theoretical suggestions, but deviates considerably in the lower MeV range which was inaccessible to those studies.