Moths Follow the Milky Way

July 17, 2025 (Spaceweather.com): Astronomers come in all shapes and sizes–even invertebrates. A new study published in Nature reveals that Australian moths can see and decipher the night sky. They pay particular attention to the Milky Way and seem capable of navigating using the Carina nebula as a visual landmark.


Above: A male Bogong moth and a diagram of their annual migration.

Every spring in southeast Australia, billions of Bogong moths take flight under cover of darkness. It’s the beginning of an epic migration as much as 1,000 kilometers long. Their destination: a small cluster of caves in the Australian Alps–places the moths have never visited before, yet somehow navigate to with remarkable precision. Their compass, it turns out, is the night sky itself.

Reaching this conclusion required the researchers to do something you probably don’t want to think about too closely: They attached the moths to tiny little tethers. Moths could lift off and pick a direction, but not escape. 

The experiment unfolded inside a special moth planetarium (pictured right). Star patterns were projected onto an overhead screen, while the ambient magnetic field was nulled by Helmholtz coils, guaranteeing that the participants could not “cheat” using magnetic navigation. When shown a normal star field, the moths oriented in the correct direction. But when the stars were scrambled into random patterns, they lost their bearings.

To dig deeper, the researchers recorded activity from visual neurons in the moths’ brains as a projected night sky rotated overhead. Neurons fired most strongly when the stars aligned with the moth’s inherited migratory heading. Some neurons were tuned to the brightest region of the Milky Way (especially near the Carina nebula) suggesting that this band of starlight is a visual landmark.

Clouds produced the next revelation: Bogong moths remained oriented even when stars were hidden. In those cases, they relied on Earth’s magnetic field instead, revealing a dual-compass system similar to that of migratory birds. When both stellar and magnetic cues were removed, the moths became disoriented again. 

Upper row: Laboratory-projected night skies during spring and autumn, and an autumn sky with its stars randomly arranged. Lower row: The moths’ reaction to each sky.

In recent years, scientists have discovered that many creatures are guided by the stars. In addition to humans, the list includes migratory songbirds, possibly seals, dung beetles, cricket frogs, and now Bogong moths. The list of lifeforms guided by magnetism is even longer, ranging in size from microbes to whales. 

You can read the original research here.

South Pacific Auroras Confirm May 10th Was a Great Storm

May 16, 2024: On the south Pacific island of New Caledonia, no one expects to see auroras. Ever. Situated about halfway between Tonga and Australia, the cigar-shaped island is too close to the equator for Northern or Southern Lights. Yet on May 10, 2024, this happened:

“I have rarely been so happy when taking a photo!” says Frédéric Desmoulins, who photographed the display from Boulouparis in the island’s south province. “I could see the red color of the auroras with my naked eye. According to the New Caledonian Astronomy Society, these photos are the first for this territory.”

“The auroral visibility from New Caledonia is really unique and extremely valuable,” says Hisashi Hayakawa, a space weather researcher at Japan’s Nagoya University. “As far as we know, the last time sky watchers saw auroras in the area was during the Carrington Event of Sept. 1859, when auroras were sighted from a ship in the Coral Sea.”

Hayakawa specializes in historical studies of great auroral storms. He tries to go back in time as far as possible. The problem is, magnetometers and modern sensors didn’t exist hundreds or thousands of years ago. Instead, he looks for records of aurora sightings in old newspapers, diaries, ships logs, even cuneiform tablets. Great Storms are identified by their low latitude–anything with naked-eye auroras below 30° MLAT (magnetic latitude).

“May 10th was definitely a Great Storm,” declares Hayakawa. “Naked-eye auroras sightings in New Caledonia (MLAT = -26.4°) and Puerto Rico (MLAT = 27.2°) confirm this in both hemispheres.”

In fact, it is among the top 20 Great Storms of the past 500 years. The above timeline from a research paper by Hayakawa has been modified to display the May 10th event. It is the green dot on the far-right end of the timeline.

This isn’t just an arcane historical curiosity. “We need to know about Great Storms of the past to understand how big storms might become today,” explains Hayakawa. “Our modern technological society depends upon it.”

Readers, if you witnessed auroras at low latitudes on May 10th, please submit your photos to our gallery and fill out this questionnaire from Hayakawa. Your observations may be included in a future research paper about this extreme storm.