Top 10 science stories of 2025, according to Bob McDonald

CBC's Bob McDonald lists ten notable science stories from 2025, highlighting the Vera C. Rubin Observatory's first images and published analyses of asteroid samples that found organic molecules.

Bob McDonald compiled a list of the top 10 science stories of 2025 for CBC Radio. The list brings together developments in astronomy, planetary science, climate and human spaceflight. It highlights new observatories and instruments, laboratory analyses of returned samples, unusual astronomical visitors, and growing concerns about ocean acidification. The piece summarizes events and discoveries that drew attention during the year. Notable facts: - The Vera C. Rubin Observatory in Chile released its first images and houses a 3.2-gigapixel digital camera; it is planned to image the southern sky repeatedly over a 10-year survey. - Analyses of material returned by the OSIRIS‑REx mission found sugars, amino acids, nucleobases and carboxylic acids in dark granular asteroid samples. - Marc Garneau, the first Canadian in space, died on June 4, 2025 at age 76; he served as president of the Canadian Space Agency and later held federal cabinet roles. - Comet 3I/ATLAS was observed in July 2025 moving at about 209,000 km/h and was identified as an interstellar object passing through the solar system. - Reports in 2025 indicated ocean acidification had reached a tipping point affecting coral reefs and other marine life, and the UN COP30 meeting in Brazil did not produce a roadmap to phase out fossil fuels. - For the first time, a privately funded mission (FRAM2) used a SpaceX Dragon capsule to fly a polar orbit, passing directly over both the north and south poles during a three-and-a-half day flight. Summary: The selections underline both expanding observational and analytical capabilities in space science and ongoing environmental concerns on Earth. The Rubin Observatory is scheduled to continue nightly sky surveys as part of a planned decade-long program, and scientists are continuing to analyse returned samples while tracking changes in ocean and polar regions.