Heart

Toastier fall weather might cause migrating monarch butterflies to wing it and change their flight plans, starting the countdown toward death. 

Eastern monarchs captured during their autumn migration and exposed to warm temperatures in the lab came out of their usual reproductive hiatus, evolutionary biologist Ken Fedorka and colleagues report August 12 in Royal Society Open Science. Breaking that hiatus means the butterflies will likely die sooner than they normally would.

“Once you decide to go reproductive, your clock starts ticking,” says Fedorka, of the University of Central Florida in Orlando. More

The sky abounds with aerosols, tiny particles with large sway over Earth’s temperature. A new NASA visualization reveals how these airborne particles swirl through the atmosphere.

The agency’s Goddard Earth Observing System tracks major aerosol types — sulfates, black carbon, dust and sea salt. It combines satellite and ground-based observations with advanced computer simulations to show how aerosols can affect air quality and visibility far from their sources. See where they loft in this visualization spanning August 1 to September 14, 2024. More

A mysterious disease has been turning sea stars into goo since 2013. Now, there’s a leading suspect behind the killings — a bacterium called Vibrio pectenicida, researchers report August 4 in Nature Ecology & Evolution. Knowing the identity of the killer could help scientists protect both captive and wild populations of sea stars.

The disease, known as sea star wasting disease, is characterized by twisted arms, lesions and rapid death. One of the worst hit species is the sunflower sea star (Pycnopodia helianthoides), which lost almost 91 percent of its population — over a billion individuals — to repeated outbreaks in 2015, 2018 and 2023. This decline has consequences for ocean ecosystems, as sunflower sea stars are predators that keep sea urchin populations in check. In their absence, sea urchins have mowed down kelp forests, which absorb atmospheric carbon dioxide and support fish, otters, sea lions and other animals.  More

A massive bolt of lightning that lit up the sky from Dallas to Kansas City, Mo., in October 2017 is officially the longest single flash ever recorded.

A reanalysis of satellite data collected during the storm revealed that this megaflash spanned 829 kilometers and lasted 7.39 seconds, says Michael Peterson, an applied physicist at Georgia Tech in Atlanta. A study describing the event was published online July 31 in the Bulletin of the American Meteorological Society.   More

July has washed across the United States with unusually destructive, deadly torrents of rain.

In the first half of the month alone, historically heavy downpours sent rivers in Central Texas spilling far beyond their banks, causing at least 130 deaths. Rains prompted flash flooding across wildfire-scarred landscapes in New Mexico and flooded subway stations in New York City. Roadways in New Jersey turned into rivers, sweeping two people to their deaths as the floodwaters carried away their car. A tropical depression dumped up to 30 centimeters of rain in one day on parts of North Carolina, leading to at least six more deaths. More

An army of treelike creatures called Ents marches to war in the second The Lord of the Rings movie, The Two Towers, walking for miles through dark forests. Once they arrive at the fortress of the evil wizard Saruman, the Ents hurl giant boulders, climb over walls and even rip open a dam to wipe out their enemy.

Mobile trees like the Ents are found throughout science fiction and fantasy worlds. The treelike alien Groot in Guardians of the Galaxy uses twiggy wings to fly. Trees called Evermean fight the main character Link in The Legend of Zelda: Tears of the Kingdom video game. And Harry Potter’s Whomping Willow — well, it whomps anyone who gets too close. More

An underwater gold rush may be on the horizon — or rather, a rush to mine the seafloor for manganese, nickel, cobalt and other minerals used in electric vehicles, solar panels and more.

Meanwhile, scientists and conservationists hope to pump the brakes on the prospect of deep-sea mining, warning that it may scar the seafloor for decades — and that there’s still far too little known about the lingering harm it might do to the deep ocean’s fragile ecosystems. More