On the morning of Jan. 18, 2003, Penny Sackett, then director of the Australian National University’s Mount Stromlo Observatory outside Canberra, received a concerning email from a student at the facility. Bush fires that had been on the horizon the day before were now rapidly approaching. The astronomers on site were considering evacuating, the student wrote.

That afternoon, from her home some miles away, Dr. Sackett watched burning embers fall from a smoky sky and worried. Later, she learned that her colleagues had escaped just in time: As the fire raced up the mountain, they fled down the other side carrying discs full of research data.

All but one of Mount Stromlo’s eight telescopes were destroyed that day, along with millions of dollars in equipment that engineers had been building for observatories around the world. The fires also destroyed 500 homes across greater Canberra, and killed four people.

The incident was an early warning for astronomy: Wildfires, exacerbated by climate change, were becoming a problem for their field. Since then, several other observatories have been damaged or threatened by fires and other extreme weather, and changing atmospheric conditions have made ground-based astronomical research more challenging.

Such incidents have drawn attention to Earth’s plight, and a growing number of astronomers are rallying to fight climate change. In 2019, professionals and students founded a global organization called Astronomers for Planet Earth. Astrobites, a journal run by graduate students in the field, held its third annual Earth Week in April. Also last month, a group of astronomers released “Climate Change for Astronomers: Causes, consequences and communication,” a collection of articles detailing the researchers’ personal experiences with the climate crisis, its impact on their work and how they might use their scientific authority to make a difference.