See a helicopter destined for Mars and a spectacular flowery frame for the Milky Way — May's best science images

In May and June of most years, NASA satellites typically begin to detect large numbers of wildland fires throughout the Top End and Arnhem Land regions of Australia's Northern Territory. On some days, especially in the afternoon, the blazes can resemble sizable wildfires in satellite imagery, spreading widely and producing expansive smoke plumes.

As California's population boomed—from 10 million in 1950 to over 40 million today—the number of people living in fire-prone areas multiplied. Over the decades, millions of new homes and commercial buildings sprang up to accommodate the needs of the state's growing population, and many of those structures stand in areas prone to wildfires.

Freshwater from melting Antarctic glaciers may be influencing the Southern Ocean in ways scientists have largely overlooked. New research, published in Frontiers in Marine Science, has found that glacial meltwater is not confined to the ocean's surface, as previously assumed, but can also be detected much deeper in coastal waters along the Western Antarctic Peninsula.

"Digital authoritarianism" refers to governments using technology for surveillance and censorship to repress dissent. China remains the master practitioner. There, sweeping surveillance and censorship at home is combined with cyber-espionage and disinformation, censorship and influence campaigns abroad.