In what year did Mauna Loa last erupt?

Mauna Loa last erupted in 1984. This eruption was significant as it marked the most recent activity from the world's largest active volcano. The eruption lasted for 22 days, beginning on January 1 and concluding on January 22, with lava flows reaching populated areas, which raised concerns among residents.

The other years mentioned are incorrect as they do not align with the actual last eruption date. There were no eruptions from Mauna Loa in 1990 or 1994, and while there have been eruptions in 1980, they did not occur at Mauna Loa itself, as that year is associated with the eruption of Kilauea. Understanding the eruption history of Mauna Loa is crucial, especially for tracking volcanic activity and its potential impact on island residents and infrastructure.