50 years ago, NASA sent 2 spacecraft to search for life on Mars – the Viking missions' findings are still discussed today

A four-legged orbiter sits on the sand, with a dish and a cloth over its parts.

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Finding life beyond the Earth would be a major scientific discovery with significant implications for all areas of science and human thought. Yet, only one direct search for extraterrestrial life has ever been conducted.