One of the week’s most groundbreaking developments came from the Red Planet. NASA unveiled evidence that a Martian rock sample may contain a “potential biosignature” – a clue of past microbial life. The Perseverance rover drilled the sample, dubbed “Sapphire Canyon,” from an ancient river delta in Jezero Crater in July 2024 nasa.gov. Scientists noticed millimeter-sized “leopard spots” in the reddish rock, which on Earth can result from chemical processes that microbes use for energy nasa.gov livescience.com. The rock is rich in clay, a material excellent at preserving organic traces of life over eons nasa.gov.