View larger. | Jupiter’s moon Ganymede is the largest moon in our solar system. Are there ice volcanoes on Ganymede? It’s possible, and now a new study has identified several good candidates. NASA’s Juno spacecraft captured this view of Ganymede on June 7, 2021. Image via NASA/ JPL-Caltech/ SwRI/ MSSS/ Kalleheikki Kannisto.
Ganymede is Jupiter’s largest moon. It has a deep ocean beneath its outer icy surface. Does it also have ice volcanoes?
A new international study has identified several good candidates on Ganymede’s frozen surface.
These are depressions in the surface surrounded by flow-like formations, where water could have erupted to the surface from below.
Does Jupiter’s largest moon Ganymede have ice volcanoes? We don’t know for sure yet, but a new international study has identified some promising candidates.
Ganymede has a deep ocean hidden beneath its icy crust. That’s led scientists to speculate it could have ice volcanoes similar to the explosive geysers on Saturn’s ocean moon Enceladus. And on May 9, 2026, researchers said they have identified four primary locations where water and other volatile materials might have erupted to Ganymede’s surface.
Anezina Solomonidou at the Hellenic Space Center (HSC) in Greece led the new study. The study also includes researchers from France, Italy, Germany, the United States, the Czech Republic, ESA and NASA’s Jet Propulsion Laboratory.
The new peer-reviewed paper is accepted for publication in the Planetary Science Journal.
Musa Patera, a depression on Ganymede some 43 miles (69 km) across. Scientists think it could have been left by an erupting ice volcano. NASA’s Galileo spacecraft captured this view on May 7, 1997. Image via NASA/ JPL/ Wikipedia.View larger. | Another view of Jupiter’s largest moon Ganymede, from the Juno flyby on June 7, 2021. Image via NASA/ JPL-Caltech/ SwRI/ MSSS; image processing by Kevin M. Gill.
Most promising locations for ice volcanoes
Ganymede has unusual depressions – called paterae – and flow-like structures on its surface. Could upwelling water have formed them?
It certainly seems possible, since Ganymede has a deep, dark ocean beneath its outer icy crust. But it depends on whether the water could get through the crust in cracks or by other means. Scientists estimate Ganymede’s crust to be about 90-95 miles (145-153 km) thick. And they estimate the ocean below to be 60 miles (96 km) deep.
Intriguingly, the flow-like structures would have been formed by flowing icy watery material. And the paterae depressions would have been the volcanic vents. It’s similar to regular volcanism, but involving icy fluids rather than molten rock.
View larger. | Saturn’s ocean moon Enceladus is famous for its geyser-like ice volcanoes. NASA’s Cassini spacecraft took this image on November 21, 2009. Does Ganymede have ice volcanoes too? Image via NASA/ JPL-Caltech/ Space Science Institute.
Implications for life
If there were – or perhaps still are – active ice volcanoes on Ganymede, that could provide clues about the conditions in the ocean below. And those conditions could determine whether Ganymede’s ocean might be habitable or not.
Ganymede is one of the most fascinating worlds in the solar system. Understanding possible cryovolcanic activity can help us better understand how ocean worlds evolve and whether they may host conditions suitable for life.
The candidate ice volcanoes will be of great interest for the European Space Agency’s upcoming Jupiter Icy Moons Explorer (JUICE) mission. JUICE was launched in 2023 and will arrive at Jupiter in 2031. It will focus on exploring the largest moons of Jupiter: Ganymede, Callisto, Io and Europa. JUICE will use its MAJIS imaging spectrometer and the JANUS camera system to take a closer look at these potential ice volcanoes.
In 2023, scientists found that Ganymede is coated in salts and organics; and in 2021, they found water vapor in Ganymede’s thin atmosphere.
Also in 2021, NASA released new closeups of Ganymede from its Juno spacecraft. Juno obtained the images on June 7, 2021.
Bottom line: Are there ice volcanoes on Ganymede? A new international study reveals several good candidates on Jupiter’s large ocean moon.
View larger. | Jupiter’s moon Ganymede is the largest moon in our solar system. Are there ice volcanoes on Ganymede? It’s possible, and now a new study has identified several good candidates. NASA’s Juno spacecraft captured this view of Ganymede on June 7, 2021. Image via NASA/ JPL-Caltech/ SwRI/ MSSS/ Kalleheikki Kannisto.
Ganymede is Jupiter’s largest moon. It has a deep ocean beneath its outer icy surface. Does it also have ice volcanoes?
A new international study has identified several good candidates on Ganymede’s frozen surface.
These are depressions in the surface surrounded by flow-like formations, where water could have erupted to the surface from below.
Does Jupiter’s largest moon Ganymede have ice volcanoes? We don’t know for sure yet, but a new international study has identified some promising candidates.
Ganymede has a deep ocean hidden beneath its icy crust. That’s led scientists to speculate it could have ice volcanoes similar to the explosive geysers on Saturn’s ocean moon Enceladus. And on May 9, 2026, researchers said they have identified four primary locations where water and other volatile materials might have erupted to Ganymede’s surface.
Anezina Solomonidou at the Hellenic Space Center (HSC) in Greece led the new study. The study also includes researchers from France, Italy, Germany, the United States, the Czech Republic, ESA and NASA’s Jet Propulsion Laboratory.
The new peer-reviewed paper is accepted for publication in the Planetary Science Journal.
Musa Patera, a depression on Ganymede some 43 miles (69 km) across. Scientists think it could have been left by an erupting ice volcano. NASA’s Galileo spacecraft captured this view on May 7, 1997. Image via NASA/ JPL/ Wikipedia.View larger. | Another view of Jupiter’s largest moon Ganymede, from the Juno flyby on June 7, 2021. Image via NASA/ JPL-Caltech/ SwRI/ MSSS; image processing by Kevin M. Gill.
Most promising locations for ice volcanoes
Ganymede has unusual depressions – called paterae – and flow-like structures on its surface. Could upwelling water have formed them?
It certainly seems possible, since Ganymede has a deep, dark ocean beneath its outer icy crust. But it depends on whether the water could get through the crust in cracks or by other means. Scientists estimate Ganymede’s crust to be about 90-95 miles (145-153 km) thick. And they estimate the ocean below to be 60 miles (96 km) deep.
Intriguingly, the flow-like structures would have been formed by flowing icy watery material. And the paterae depressions would have been the volcanic vents. It’s similar to regular volcanism, but involving icy fluids rather than molten rock.
View larger. | Saturn’s ocean moon Enceladus is famous for its geyser-like ice volcanoes. NASA’s Cassini spacecraft took this image on November 21, 2009. Does Ganymede have ice volcanoes too? Image via NASA/ JPL-Caltech/ Space Science Institute.
Implications for life
If there were – or perhaps still are – active ice volcanoes on Ganymede, that could provide clues about the conditions in the ocean below. And those conditions could determine whether Ganymede’s ocean might be habitable or not.
Ganymede is one of the most fascinating worlds in the solar system. Understanding possible cryovolcanic activity can help us better understand how ocean worlds evolve and whether they may host conditions suitable for life.
The candidate ice volcanoes will be of great interest for the European Space Agency’s upcoming Jupiter Icy Moons Explorer (JUICE) mission. JUICE was launched in 2023 and will arrive at Jupiter in 2031. It will focus on exploring the largest moons of Jupiter: Ganymede, Callisto, Io and Europa. JUICE will use its MAJIS imaging spectrometer and the JANUS camera system to take a closer look at these potential ice volcanoes.
In 2023, scientists found that Ganymede is coated in salts and organics; and in 2021, they found water vapor in Ganymede’s thin atmosphere.
Also in 2021, NASA released new closeups of Ganymede from its Juno spacecraft. Juno obtained the images on June 7, 2021.
Bottom line: Are there ice volcanoes on Ganymede? A new international study reveals several good candidates on Jupiter’s large ocean moon.
Terry O’Leary of Virginia Beach, Virginia, captured the classic anvil shape of cumulonimbus clouds – out the window of an airplane – in early summer 2003 over central Virginia. Image via NASA GLOBE Clouds.
Cumulonimbus clouds are among the most awe-inspiring of cloud formations. They might start as low as 0.6 miles (1,000 meters) above Earth’s surface. And their tops can reach up to 7 miles (12,000 meters) or more. So they can tower for miles into the sky, bumping into Earth’s stratosphere. Cumulonimbus clouds are known to flatten out into an anvil shape on top. They’re sometimes called thunderheads, because they’re the engines behind thunderstorms, severe weather and even tornadoes.
If you see a cumulonimbus cloud bubbling upward into the sky, get ready to take cover!
The word cumulonimbus comes from the Latin cumulo meaning heap or pile and nimbus meaning cloud. They begin as puffy white cumulus clouds that can rapidly grow under the right conditions.
How do they form?
As with cumulus clouds, which are fair-weather clouds, a cumulonimbus cloud begins with the process of convection. That’s what happens when warm air rises, because it’s less dense than the cooler air around it. Convection tends to happen on warm days when Earth’s surface heats unevenly, for example, in the afternoon over land. As the warm, moist air rises, it cools and condenses, forming puffy cumulus clouds.
If the rising air continues to be warmer than its surroundings, it’ll keep growing. That’s when it’ll form larger and taller clouds. When the atmosphere is particularly unstable – meaning that temperature decreases rapidly with height – this upward motion becomes more vigorous. In this case, a cumulus cloud can quickly grow into a cumulonimbus cloud.
Inside a developing cumulonimbus cloud, there are both updrafts and downdrafts. The winds of the updrafts can reach speeds of more than 100 mph (161 kph). These updrafts carry water vapor high into the atmosphere, where it condenses into water droplets or ice crystals. This process releases latent heat, fueling further cloud growth. The top of the cloud eventually flattens out when it hits the tropopause, the divider between the lower troposphere (the bottom layer of the atmosphere, where we live) and the higher stratosphere.
Watch this time lapse of cumulus clouds growing into a towering cumulonimbus cloud with an anvil top.
When and where do you see cumulonimbus clouds?
Cumulonimbus clouds can form anywhere in the world. But they’re most common in regions where warm, moist air is prevalent. In the United States, for instance, you can frequently see these clouds in the spring and summer months. That’s especially true if you live in the U.S. Great Plains, Midwest and Southeast, where warm, humid air from the Gulf of Mexico interacts with cooler air masses. But you can also see these clouds nearly every summer afternoon in central Florida, thanks to sea breezes and lots of tropical moisture.
And indeed – although they can also occur at other times of the day or night – afternoon and early evening are the best times to look for cumulonimbus clouds. That’s when surface heating from the sun is at its peak.
What kind of weather do cumulonimbus clouds bring?
Cumulonimbus clouds are synonymous with severe weather. They are the primary cloud type responsible for thunderstorms.
Depending on their intensity and the conditions around them, cumulonimbus clouds can produce:
Torrential rain: Localized downpours that can lead to flash flooding.
Hail: Ice particles carried in updrafts and downdrafts, growing larger before falling to the ground.
Strong winds: Often associated with downdrafts or microbursts, which can cause damage similar to weak tornadoes.
Tornadoes: In the most severe storms, rotating updrafts can spawn tornadoes.
Lightning: Electrical charges can trigger lightning within the cloud and also send bolts careening to the ground.
Due to all these hazards, airplanes fly around – and not through – cumulonimbus clouds.
In this video, you can see air traffic diverting around cumulonimbus clouds and then circling, waiting for the storms to clear the Atlanta airport before landing.
Stay safe
When you see a cumulonimbus cloud, think safety. The lightning from these clouds can strike miles away, far from where the cloud is producing rain. Hail can be dangerous for people and animals without shelter. Torrential rain can cause flash flooding, and strong winds and tornadoes can send objects flying.
Cumulonimbus clouds are awe-inspiring and formidable phenomena that remind us of nature’s raw power. Spotting a cumulonimbus cloud offers us a glimpse into the dynamic processes of the atmosphere. And it provides a warning of the powerful forces brewing above.
View at EarthSky Community Photos. | Ross Stone captured this image in California on July 31, 2024. Ross wrote: “When I saw this gigantic cumulonimbus cloud I had to pull off to the side of the road and take out my camera. I absolutely love the summertime clouds.” Thank you, Ross!
Bottom line: Cumulonimbus clouds, sometimes called thunderheads, are towering formations that can bring severe storms such as hail, lightning, flooding and tornadoes.
Terry O’Leary of Virginia Beach, Virginia, captured the classic anvil shape of cumulonimbus clouds – out the window of an airplane – in early summer 2003 over central Virginia. Image via NASA GLOBE Clouds.
Cumulonimbus clouds are among the most awe-inspiring of cloud formations. They might start as low as 0.6 miles (1,000 meters) above Earth’s surface. And their tops can reach up to 7 miles (12,000 meters) or more. So they can tower for miles into the sky, bumping into Earth’s stratosphere. Cumulonimbus clouds are known to flatten out into an anvil shape on top. They’re sometimes called thunderheads, because they’re the engines behind thunderstorms, severe weather and even tornadoes.
If you see a cumulonimbus cloud bubbling upward into the sky, get ready to take cover!
The word cumulonimbus comes from the Latin cumulo meaning heap or pile and nimbus meaning cloud. They begin as puffy white cumulus clouds that can rapidly grow under the right conditions.
How do they form?
As with cumulus clouds, which are fair-weather clouds, a cumulonimbus cloud begins with the process of convection. That’s what happens when warm air rises, because it’s less dense than the cooler air around it. Convection tends to happen on warm days when Earth’s surface heats unevenly, for example, in the afternoon over land. As the warm, moist air rises, it cools and condenses, forming puffy cumulus clouds.
If the rising air continues to be warmer than its surroundings, it’ll keep growing. That’s when it’ll form larger and taller clouds. When the atmosphere is particularly unstable – meaning that temperature decreases rapidly with height – this upward motion becomes more vigorous. In this case, a cumulus cloud can quickly grow into a cumulonimbus cloud.
Inside a developing cumulonimbus cloud, there are both updrafts and downdrafts. The winds of the updrafts can reach speeds of more than 100 mph (161 kph). These updrafts carry water vapor high into the atmosphere, where it condenses into water droplets or ice crystals. This process releases latent heat, fueling further cloud growth. The top of the cloud eventually flattens out when it hits the tropopause, the divider between the lower troposphere (the bottom layer of the atmosphere, where we live) and the higher stratosphere.
Watch this time lapse of cumulus clouds growing into a towering cumulonimbus cloud with an anvil top.
When and where do you see cumulonimbus clouds?
Cumulonimbus clouds can form anywhere in the world. But they’re most common in regions where warm, moist air is prevalent. In the United States, for instance, you can frequently see these clouds in the spring and summer months. That’s especially true if you live in the U.S. Great Plains, Midwest and Southeast, where warm, humid air from the Gulf of Mexico interacts with cooler air masses. But you can also see these clouds nearly every summer afternoon in central Florida, thanks to sea breezes and lots of tropical moisture.
And indeed – although they can also occur at other times of the day or night – afternoon and early evening are the best times to look for cumulonimbus clouds. That’s when surface heating from the sun is at its peak.
What kind of weather do cumulonimbus clouds bring?
Cumulonimbus clouds are synonymous with severe weather. They are the primary cloud type responsible for thunderstorms.
Depending on their intensity and the conditions around them, cumulonimbus clouds can produce:
Torrential rain: Localized downpours that can lead to flash flooding.
Hail: Ice particles carried in updrafts and downdrafts, growing larger before falling to the ground.
Strong winds: Often associated with downdrafts or microbursts, which can cause damage similar to weak tornadoes.
Tornadoes: In the most severe storms, rotating updrafts can spawn tornadoes.
Lightning: Electrical charges can trigger lightning within the cloud and also send bolts careening to the ground.
Due to all these hazards, airplanes fly around – and not through – cumulonimbus clouds.
In this video, you can see air traffic diverting around cumulonimbus clouds and then circling, waiting for the storms to clear the Atlanta airport before landing.
Stay safe
When you see a cumulonimbus cloud, think safety. The lightning from these clouds can strike miles away, far from where the cloud is producing rain. Hail can be dangerous for people and animals without shelter. Torrential rain can cause flash flooding, and strong winds and tornadoes can send objects flying.
Cumulonimbus clouds are awe-inspiring and formidable phenomena that remind us of nature’s raw power. Spotting a cumulonimbus cloud offers us a glimpse into the dynamic processes of the atmosphere. And it provides a warning of the powerful forces brewing above.
View at EarthSky Community Photos. | Ross Stone captured this image in California on July 31, 2024. Ross wrote: “When I saw this gigantic cumulonimbus cloud I had to pull off to the side of the road and take out my camera. I absolutely love the summertime clouds.” Thank you, Ross!
Bottom line: Cumulonimbus clouds, sometimes called thunderheads, are towering formations that can bring severe storms such as hail, lightning, flooding and tornadoes.
Have you heard of synchronous fireflies? It’s an amazing night spectacle where thousands of these glowing insects pulse in perfect rhythm across a forest, turning the darkness into a living wave of light. Image via P. Driessche/ National Park Service.
It’s synchronous firefly season! Every year between mid-May and mid-June, locations such as the Great Smoky Mountains National Park in North Carolina and Tennessee, and Congaree in South Carolina, see fireflies flicker in harmony as night falls. The phenomenon happens as male fireflies seek mates. These fireflies – aka lightning bugs – flash with a distinct rhythm: a few quick bursts of light followed by a several-second pause, then more bursts. In person, the display looks like a wave of light passing over a hillside.
And you don’t need to join a guided group to see synchronous fireflies. You don’t even have to be in these exact regions of the parks. In fact, people who live in the Smokies have been known to see synchronous fireflies in their backyard.
Just know that these insects prefer northern hardwood forest habitats such as the kind you find in Tennessee, North Carolina and South Carolina.
Fireflies are bioluminescent
Fireflies are bioluminescent. That means that – through a chemical reaction in the insects’ bodies – they’re able to emit light.
Luciferin is the key for creatures that emit this living light. Luciferin is a molecule that reacts in the presence of the enzyme luciferase to produce light. A chemical reaction between the two splits off a molecular fragment. That, in turn, produces an excited state that emits light.
Both words – luciferin and luciferase – come from the same root as lucifer. That word originates from Latin, combining lux (light) and ferre (to bring). It translates to “light-bringer” or “morning star.” It was the Roman name for Venus, when that brightest of planets is visible in the morning. It only later gained a darker association.
A team of researchers from University of Colorado Boulder has been trying to understand how relatively simple insects manage to coordinate such feats of synchronization.
They published an important study about them on September 23, 2020, in the peer-reviewedJournal of the Royal Society Interface. This study suggests that – rather than flash according to some innate rhythm – the fireflies observe what their neighbors are doing. Then they adjust their behavior to match.
The researchers discovered that the fireflies don’t behave the same way when they’re alone as when they’re in a big group. For example, the team found that a single male firefly alone in the tent would flash without a good sense of rhythm, a few bursts here, a few bursts there. But with more fireflies in the tent, things began to change. Raphaël Sarfati, lead author of the study and a postdoctoral researcher at CU Boulder at the time, said:
When you start putting 20 fireflies together, that’s when you start observing what you see in the wild. You’ve got regular bursts of flashes, and they’re all synchronized.
That suggested to the researchers that the fireflies likely aren’t hardwired to flash with a particular pattern. Instead, their light displays seem to be more social. Bugs watch what their neighbors are doing and try to follow along.
A video of fireflies from the research team in the 2020 study.
More synchronous fireflies studies
Since that early study, these researchers have been busy:
In 2021, they expanded their 3D stereoscopic camera tracking to study large, natural swarms of fireflies in the Great Smoky Mountains. They found that synchronization isn’t just a simultaneous group flash; instead, it propagates through the swarm as “information waves.” See Self-organization in natural swarms of synchronous fireflies in Science Advances (July 2021).
In 2023, the researchers reported they’d solved a massive puzzle regarding the fireflies’ “dark phase” (the several-second pause between flash bursts). They said that, when completely isolated, an individual firefly has no internal clock or regular rhythm; it just flashes completely at random. See Emergent periodicity in the collective synchronous flashing of fireflies (March 2023).
Fireflies are found across South America, southern Africa, Australia and New Zealand. But large-scale synchronized swarming displays aren’t typically a characteristic feature. Instead, fireflies are typically seen in lower-density populations, appearing as individual or small-group flashes.
Even so, their behavior remains fundamentally tied to night, with males flashing in low light to locate mates and relying on darkness to make their signals visible. Across both hemispheres, these phenomena reinforce a broader theme closely tied to night sky preservation: protecting dark skies also protects the natural behaviors of nocturnal species that depend on darkness to communicate, hunt and survive.
Meanwhile, in the Southern Hemisphere, a closer visual parallel to synchronous fireflies might be found in glowworms, particularly in New Zealand’s cave systems such as Waitomo. There, too, you can take guided tours.
In the caves, darkness becomes the essential stage for Arachnocampa luminosa, commonly known as New Zealand glowworm, whose larvae emit a soft blue-green light to attract prey.
Glowworm lights aren’t synchronized either, though. Here’s what they do instead. Thousands of individual points of glowworm light combine to form a still, star-like canopy, often described as stepping into a terrestrial night sky.
A glowworm cave – Waitmo – in New Zealand. Image via New Zealand.com.
Bottom line: The synchronous fireflies are back! These lightning bugs flash in harmony in the Great Smoky Mountains and other nearby parks from mid-May to mid-June. Read more about them here.
Have you heard of synchronous fireflies? It’s an amazing night spectacle where thousands of these glowing insects pulse in perfect rhythm across a forest, turning the darkness into a living wave of light. Image via P. Driessche/ National Park Service.
It’s synchronous firefly season! Every year between mid-May and mid-June, locations such as the Great Smoky Mountains National Park in North Carolina and Tennessee, and Congaree in South Carolina, see fireflies flicker in harmony as night falls. The phenomenon happens as male fireflies seek mates. These fireflies – aka lightning bugs – flash with a distinct rhythm: a few quick bursts of light followed by a several-second pause, then more bursts. In person, the display looks like a wave of light passing over a hillside.
And you don’t need to join a guided group to see synchronous fireflies. You don’t even have to be in these exact regions of the parks. In fact, people who live in the Smokies have been known to see synchronous fireflies in their backyard.
Just know that these insects prefer northern hardwood forest habitats such as the kind you find in Tennessee, North Carolina and South Carolina.
Fireflies are bioluminescent
Fireflies are bioluminescent. That means that – through a chemical reaction in the insects’ bodies – they’re able to emit light.
Luciferin is the key for creatures that emit this living light. Luciferin is a molecule that reacts in the presence of the enzyme luciferase to produce light. A chemical reaction between the two splits off a molecular fragment. That, in turn, produces an excited state that emits light.
Both words – luciferin and luciferase – come from the same root as lucifer. That word originates from Latin, combining lux (light) and ferre (to bring). It translates to “light-bringer” or “morning star.” It was the Roman name for Venus, when that brightest of planets is visible in the morning. It only later gained a darker association.
A team of researchers from University of Colorado Boulder has been trying to understand how relatively simple insects manage to coordinate such feats of synchronization.
They published an important study about them on September 23, 2020, in the peer-reviewedJournal of the Royal Society Interface. This study suggests that – rather than flash according to some innate rhythm – the fireflies observe what their neighbors are doing. Then they adjust their behavior to match.
The researchers discovered that the fireflies don’t behave the same way when they’re alone as when they’re in a big group. For example, the team found that a single male firefly alone in the tent would flash without a good sense of rhythm, a few bursts here, a few bursts there. But with more fireflies in the tent, things began to change. Raphaël Sarfati, lead author of the study and a postdoctoral researcher at CU Boulder at the time, said:
When you start putting 20 fireflies together, that’s when you start observing what you see in the wild. You’ve got regular bursts of flashes, and they’re all synchronized.
That suggested to the researchers that the fireflies likely aren’t hardwired to flash with a particular pattern. Instead, their light displays seem to be more social. Bugs watch what their neighbors are doing and try to follow along.
A video of fireflies from the research team in the 2020 study.
More synchronous fireflies studies
Since that early study, these researchers have been busy:
In 2021, they expanded their 3D stereoscopic camera tracking to study large, natural swarms of fireflies in the Great Smoky Mountains. They found that synchronization isn’t just a simultaneous group flash; instead, it propagates through the swarm as “information waves.” See Self-organization in natural swarms of synchronous fireflies in Science Advances (July 2021).
In 2023, the researchers reported they’d solved a massive puzzle regarding the fireflies’ “dark phase” (the several-second pause between flash bursts). They said that, when completely isolated, an individual firefly has no internal clock or regular rhythm; it just flashes completely at random. See Emergent periodicity in the collective synchronous flashing of fireflies (March 2023).
Fireflies are found across South America, southern Africa, Australia and New Zealand. But large-scale synchronized swarming displays aren’t typically a characteristic feature. Instead, fireflies are typically seen in lower-density populations, appearing as individual or small-group flashes.
Even so, their behavior remains fundamentally tied to night, with males flashing in low light to locate mates and relying on darkness to make their signals visible. Across both hemispheres, these phenomena reinforce a broader theme closely tied to night sky preservation: protecting dark skies also protects the natural behaviors of nocturnal species that depend on darkness to communicate, hunt and survive.
Meanwhile, in the Southern Hemisphere, a closer visual parallel to synchronous fireflies might be found in glowworms, particularly in New Zealand’s cave systems such as Waitomo. There, too, you can take guided tours.
In the caves, darkness becomes the essential stage for Arachnocampa luminosa, commonly known as New Zealand glowworm, whose larvae emit a soft blue-green light to attract prey.
Glowworm lights aren’t synchronized either, though. Here’s what they do instead. Thousands of individual points of glowworm light combine to form a still, star-like canopy, often described as stepping into a terrestrial night sky.
A glowworm cave – Waitmo – in New Zealand. Image via New Zealand.com.
Bottom line: The synchronous fireflies are back! These lightning bugs flash in harmony in the Great Smoky Mountains and other nearby parks from mid-May to mid-June. Read more about them here.
At 1 UTC on May 21, 2026, the sun will enter the astrological sign of Gemini. But – in the real sky – the sun doesn’t cross the official IAU constellation boundary into Gemini until a month later, around the June solstice (June 21).
Why is there a difference between signs as defined by astrologers, and constellations as defined by an international organization of astronomers?
The signs of Aries, Taurus, etc. – still used in astrology – are 30 degree-wide bands along the ecliptic, starting at longitude 0 degrees. This is also known as the First Point of Aries. The constellations are areas of the starry sky, defined since 1930 by specific lines and boundaries. The two coincided, somewhat over 2,000 years ago, when the system of astrological signs was defined. But precession – the wobbling of Earth’s spin axis over a cycle of 25,800 years – has made them increasingly divergent.
Chart showing the sun’s movement through the constellations as defined by astronomers. You can see that the sun won’t enter Gemini until around June 21. Chart via Guy Ottewell’s 2026 Astronomical Calendar
The sun’s path through the sky
The chart above shows the sun’s travel from around March 20, 2026, (the spring or vernal equinox) to September 21, 2026. You can see that the sun does indeed enter Taurus around May 21. But this brings it to the beginning (roughly) of constellation Taurus, not Gemini. It will have to travel another 30 degrees – one month – to enter Gemini.
The stars and constellations stay fixed. What shifts over time is the celestial equator – the “belt,” you could say, of the spinning Earth – and the mapping system based on it.
Picturing constellations and signs
Mentally move them. Imagine the sun’s March-to-May track, and the celestial equator – the blue line on the chart above – slid 30 degrees to the left (east), while everything else stays in place. The crossing-point of equator and ecliptic – which is the zero point for longitude – is 30 degrees to the left: it is at what is now longitude 30 degrees, the beginning of Aries. So it really is then the First Point of Aries. In this mental projection, the sun is at the First Point of Aries in March, and arrives at the gates of Gemini at this time in May.
This was how things stood when the system of signs was agreed upon, around 2,000 years ago.
You can, with some imagination, see it in your sky, or on the chart above.
There is the sun (below the horizon) at its May 21, 2026, position where it enters the astrological sign of Gemini. If this were 150 BCE it would be 30 degrees on – at what is now longitude 90 degrees – the solstice point of our time, by the feet of Gemini.
Bottom line: What is the difference between the signs of the zodiac and the constellations of the zodiac? Astronomer Guy Ottewell illustrates and discusses this difference.
At 1 UTC on May 21, 2026, the sun will enter the astrological sign of Gemini. But – in the real sky – the sun doesn’t cross the official IAU constellation boundary into Gemini until a month later, around the June solstice (June 21).
Why is there a difference between signs as defined by astrologers, and constellations as defined by an international organization of astronomers?
The signs of Aries, Taurus, etc. – still used in astrology – are 30 degree-wide bands along the ecliptic, starting at longitude 0 degrees. This is also known as the First Point of Aries. The constellations are areas of the starry sky, defined since 1930 by specific lines and boundaries. The two coincided, somewhat over 2,000 years ago, when the system of astrological signs was defined. But precession – the wobbling of Earth’s spin axis over a cycle of 25,800 years – has made them increasingly divergent.
Chart showing the sun’s movement through the constellations as defined by astronomers. You can see that the sun won’t enter Gemini until around June 21. Chart via Guy Ottewell’s 2026 Astronomical Calendar
The sun’s path through the sky
The chart above shows the sun’s travel from around March 20, 2026, (the spring or vernal equinox) to September 21, 2026. You can see that the sun does indeed enter Taurus around May 21. But this brings it to the beginning (roughly) of constellation Taurus, not Gemini. It will have to travel another 30 degrees – one month – to enter Gemini.
The stars and constellations stay fixed. What shifts over time is the celestial equator – the “belt,” you could say, of the spinning Earth – and the mapping system based on it.
Picturing constellations and signs
Mentally move them. Imagine the sun’s March-to-May track, and the celestial equator – the blue line on the chart above – slid 30 degrees to the left (east), while everything else stays in place. The crossing-point of equator and ecliptic – which is the zero point for longitude – is 30 degrees to the left: it is at what is now longitude 30 degrees, the beginning of Aries. So it really is then the First Point of Aries. In this mental projection, the sun is at the First Point of Aries in March, and arrives at the gates of Gemini at this time in May.
This was how things stood when the system of signs was agreed upon, around 2,000 years ago.
You can, with some imagination, see it in your sky, or on the chart above.
There is the sun (below the horizon) at its May 21, 2026, position where it enters the astrological sign of Gemini. If this were 150 BCE it would be 30 degrees on – at what is now longitude 90 degrees – the solstice point of our time, by the feet of Gemini.
Bottom line: What is the difference between the signs of the zodiac and the constellations of the zodiac? Astronomer Guy Ottewell illustrates and discusses this difference.
Radio light from quasar TXS 2005+403 travels roughly 10 billion light-years to reach Earth. It passes through the Cygnus region, one of the most turbulent environments in our Milky Way Galaxy. On the left, this artist’s illustration shows the quasar as it truly appears. On the right, we see how turbulent gas distorts scientists’ view of the quasar in much the same way heat haze from a fire warps our view of the objects behind it. A new study has, for the 1st time, directly detected how this interstellar turbulence distorts light from distant objects. Image via Center for Astrophysics/ Melissa Weiss.
For the first time, astronomers have directly detected how turbulent gas between stars distorts light.
These turbulent structures occur at scales roughly the size of our solar system.
Understanding this distortion could help scientists “de-blur” images of the supermassive black hole at the center of our galaxy, Sagittarius A*.
The space between stars in our galaxy, known as the interstellar medium, is churning with clouds of ionized gas and electrons. When waves of light from distant objects pass through this turbulent material, they are bent and distorted in the same way heat haze rising above a fire distorts our view of everything behind it. That distortion has long allowed astronomers to infer that the turbulence exists, but understanding its structure has remained out of reach … until now.
Now, astronomers say they have made the first direct detection of interstellar turbulence distorting light. And they say the findings will help us produce clearer images of the supermassive black hole at the center of the Milky Way Galaxy.
The researchers, led by the Harvard and Smithsonian’s Center for Astrophysics, published their peer-reviewed research in The Astrophysical Journal Letters on May 13, 2026.
An insightful quasar
To measure the interstellar turbulence, astronomers set their sights on quasar TXS 2005+403, a bright radio source powered by a supermassive black hole that is located roughly 10 billion light-years away from Earth, in the constellation Cygnus the Swan.
As radio light from the quasar travels toward Earth, it passes through the Cygnus region of the galaxy. That’s one of the most turbulent and strongly scattering environments in the Milky Way. The turbulence deflects and distorts the radio waves.
Alexander Plavin, an astronomer at the CfA’s Black Hole Initiative and lead author of the new paper, said:
Most of what we see in the radio data isn’t coming from the quasar itself, it’s coming from the scattering caused by the turbulence in this region of the Milky Way. That scattering and the distortions that come with it are what allows us to study the turbulence and better understand and infer its structure.
Imagery revealed light patterns consistent with turbulence
To get a better look at the effects of interstellar turbulence on light from the quasar, scientists analyzed nearly a decade of archival observations from the U.S. National Science Foundation’s Very Long Baseline Array (NSF VLBA). Operated by NSF’s National Radio Astronomy Observatory (NSF NRAO), the NSF VLBA is a network of ten radio telescopes spread across the country.
Scientists expected that when radio light from TXS 2005+403 passed though the Milky Way, it would spread out into a smooth blur and fade away. Instead, they found persistent, distinct patterns, producing structured, patchy distortions in the light that could only have come from turbulence. Pavin said:
The most distant pairs of telescopes should not have seen the quasar image, but to our surprise, they clearly detected its signal, or faint glow.
It can’t be explained by simple blurring or by the quasar itself, and it behaves the way turbulence is expected to, which is how we know we’re seeing the effects of interstellar turbulence.
Plavin added that the scattering properties along this line of sight through the galaxy remain persistent over time.
Understanding how gas behaves in our galaxy
The findings have significant implications for future astronomical research. The turbulence the researchers detected exists at scales roughly the size of our solar system. Understanding it helps explain how energy moves through the galaxy and how gas behaves before collapsing to form new stars.
The findings may also directly inform efforts to sharpen images of black holes. The Event Horizon Telescope’s images of Sagittarius A*, the supermassive black hole at the center of the Milky Way, are degraded by this same interstellar scattering. Studying how turbulence scatters radio light over time and different frequencies provides a path toward removing its effects from those images.
The team has begun a follow-up observing campaign with the NSF VLBA running through 2026. They aim to measure the specific properties of the screen created by this turbulence and track how it changes as the gas moves relative to Earth.
Radio light from quasar TXS 2005+403 travels roughly 10 billion light-years to reach Earth. It passes through the Cygnus region, one of the most turbulent environments in our Milky Way Galaxy. On the left, this artist’s illustration shows the quasar as it truly appears. On the right, we see how turbulent gas distorts scientists’ view of the quasar in much the same way heat haze from a fire warps our view of the objects behind it. A new study has, for the 1st time, directly detected how this interstellar turbulence distorts light from distant objects. Image via Center for Astrophysics/ Melissa Weiss.
For the first time, astronomers have directly detected how turbulent gas between stars distorts light.
These turbulent structures occur at scales roughly the size of our solar system.
Understanding this distortion could help scientists “de-blur” images of the supermassive black hole at the center of our galaxy, Sagittarius A*.
The space between stars in our galaxy, known as the interstellar medium, is churning with clouds of ionized gas and electrons. When waves of light from distant objects pass through this turbulent material, they are bent and distorted in the same way heat haze rising above a fire distorts our view of everything behind it. That distortion has long allowed astronomers to infer that the turbulence exists, but understanding its structure has remained out of reach … until now.
Now, astronomers say they have made the first direct detection of interstellar turbulence distorting light. And they say the findings will help us produce clearer images of the supermassive black hole at the center of the Milky Way Galaxy.
The researchers, led by the Harvard and Smithsonian’s Center for Astrophysics, published their peer-reviewed research in The Astrophysical Journal Letters on May 13, 2026.
An insightful quasar
To measure the interstellar turbulence, astronomers set their sights on quasar TXS 2005+403, a bright radio source powered by a supermassive black hole that is located roughly 10 billion light-years away from Earth, in the constellation Cygnus the Swan.
As radio light from the quasar travels toward Earth, it passes through the Cygnus region of the galaxy. That’s one of the most turbulent and strongly scattering environments in the Milky Way. The turbulence deflects and distorts the radio waves.
Alexander Plavin, an astronomer at the CfA’s Black Hole Initiative and lead author of the new paper, said:
Most of what we see in the radio data isn’t coming from the quasar itself, it’s coming from the scattering caused by the turbulence in this region of the Milky Way. That scattering and the distortions that come with it are what allows us to study the turbulence and better understand and infer its structure.
Imagery revealed light patterns consistent with turbulence
To get a better look at the effects of interstellar turbulence on light from the quasar, scientists analyzed nearly a decade of archival observations from the U.S. National Science Foundation’s Very Long Baseline Array (NSF VLBA). Operated by NSF’s National Radio Astronomy Observatory (NSF NRAO), the NSF VLBA is a network of ten radio telescopes spread across the country.
Scientists expected that when radio light from TXS 2005+403 passed though the Milky Way, it would spread out into a smooth blur and fade away. Instead, they found persistent, distinct patterns, producing structured, patchy distortions in the light that could only have come from turbulence. Pavin said:
The most distant pairs of telescopes should not have seen the quasar image, but to our surprise, they clearly detected its signal, or faint glow.
It can’t be explained by simple blurring or by the quasar itself, and it behaves the way turbulence is expected to, which is how we know we’re seeing the effects of interstellar turbulence.
Plavin added that the scattering properties along this line of sight through the galaxy remain persistent over time.
Understanding how gas behaves in our galaxy
The findings have significant implications for future astronomical research. The turbulence the researchers detected exists at scales roughly the size of our solar system. Understanding it helps explain how energy moves through the galaxy and how gas behaves before collapsing to form new stars.
The findings may also directly inform efforts to sharpen images of black holes. The Event Horizon Telescope’s images of Sagittarius A*, the supermassive black hole at the center of the Milky Way, are degraded by this same interstellar scattering. Studying how turbulence scatters radio light over time and different frequencies provides a path toward removing its effects from those images.
The team has begun a follow-up observing campaign with the NSF VLBA running through 2026. They aim to measure the specific properties of the screen created by this turbulence and track how it changes as the gas moves relative to Earth.
Hercules is a faint constellation. But its mid-section contains the easy-to-see Keystone star pattern. You can find Hercules between the bright stars Vega in Lyra the Harp, and Arcturus in Boötes the Herdsman. And once you find its Keystone, you can easily locate M13, the Hercules cluster. Chart via EarthSky.
Use Vega to locate the Keystone in Hercules
In late spring from mid-northern latitudes, you can easily find the brilliant blue-white star Vega in the eastern sky at dusk and nightfall. And this star, which lies in the constellation Lyra the Harp, acts as your guide star to the Keystone, a wedge-shaped pattern of four stars in neighboring constellation Hercules.
Look for the Keystone asterism – star pattern – to the upper right of Vega. If you hold your fist at arm’s length, it’ll easily fit between Vega and the Keystone.
Also, you can locate the Keystone by using Vega in conjunction with the brilliant yellow-orange star Arcturus, in Boötes the Herdsman. From mid-northern latitudes this time of year, Arcturus is found quite high in the eastern sky at nightfall. Then, by late evening, Arcturus moves high overhead. The Keystone is found about 1/3 of the way from Vega to Arcturus.
As darkness falls, look for the Keystone in Hercules to the upper right of the brilliant star Vega. Chart via EarthSky.
Most likely, you’ll need binoculars to see the Hercules cluster. Sharp-eyed people can see it with the unaided eye in a dark, transparent sky. Through binoculars, this cluster looks like a dim smudge or a somewhat fuzzy star. However, a telescope begins to resolve this faint fuzzy object into what it really is: a huge globe-shaped stellar city populated with hundreds of thousands of stars!
The Keystone and the Hercules cluster will swing high overhead after midnight, and are found in the western sky before dawn.
Can you find the Keystone on this chart? See the compact grouping of 4 stars at the center of Hercules? That’s it. Note the whereabouts of Messier 13 within the Keystone pattern. Also, above the Keystone is another globular cluster, M92. It’s a bit smaller and dimmer than M13, but also easy to pick up in binoculars or a telescope. Image via International Astronomical Union/ Sky & Telescope/ Wikimedia Commons (CC BY 3.0).
Photos of M13 from EarthSky Community Photos
View at EarthSky Community Photos. | Steven Bellavia in Surry, Virginia, made this comparison of 2 famous globular star clusters on April 17, 2026. Steven wrote: “A large and a giant globular cluster: M13 and Omega Centauri (NGC 5139), imaged with the same gear on the same night.” Steven told us that M13 – the cluster on the left, about 22,000 light-years away – contains approximately 400,000 stars and takes up about 0.36 degrees of sky. Omega Centauri, aka NGC 5139, is a giant globular cluster. It’s on the right in this composite. It contains 10 million stars and takes up about 0.6 degrees of sky, larger than a full moon seen from Earth. It is 17,000 light years away. Thank you, Steven!View at EarthSky Community Photos. | Tameem Altameemi in the United Arab Emirates (UAE), captured this telescopic view of the great Hercules Cluster on April 26, 2025. Tameem wrote: “This image features the beautiful globular cluster Messier 13, also historically known as the Al-Jathi Cluster. Located in the constellation Hercules, M13 lies about 22,200 light-years away from Earth and has an estimated age of 11.65 billion years. It contains several hundred thousand ancient stars, densely packed into a region about 213 light-years across. In the same field of view, the spiral galaxy NGC 6207 and the faint active galaxy IC 4617 are visible.” Thank you, Tameem!View at EarthSky Community Photos. | Tom Cofer in Lakewood Ranch, Florida, captured this telescopic view of Messier 13, the Great Globular Cluster in Hercules, on March 14, 2025. Tom wrote: “A snow globe of stars!” Thank you, Tom!
Finding the Hercules Cluster from Southern Latitudes
The great globular cluster M13 is also visible for Southern Hemisphere viewers, although it never climbs especially high above the horizon and never becomes as prominent as it does for observers farther north. Like Northern Hemisphere observers, southern observers require dark skies to glimpse a very faint M13 with the unaided eye. Through binoculars it appears as a faint hazy patch, while telescopes begin to resolve its densely packed population of ancient stars.
M13’s home constellation Hercules becomes visible during late autumn and is best placed during winter nights. You can still find Hercules’ Keystone by using the bright star Vega, low in the northeastern sky, to guide the way west. Because Hercules remains low above the northern horizon from southern latitudes, a clear northern horizon and dark skies greatly improve the view. Even so, the Keystone can still be recognised as a compact quadrilateral pattern west (or left) of Vega.
M13 competes with the Southern Hemisphere’s own spectacular globular clusters, particularly Omega Centauri and 47 Tucanae. Both appear much larger and brighter from southern latitudes, often climbing high overhead, and provide a striking comparison to the Hercules Cluster. Nonetheless, M13 is a worthwhile target for Southern Hemisphere observers to seek out.
Bottom line: Let the bright star Vega guide you to a famous star pattern in Hercules – called the Keystone – and then to the Hercules cluster, aka M13, a famous globular star cluster.
Hercules is a faint constellation. But its mid-section contains the easy-to-see Keystone star pattern. You can find Hercules between the bright stars Vega in Lyra the Harp, and Arcturus in Boötes the Herdsman. And once you find its Keystone, you can easily locate M13, the Hercules cluster. Chart via EarthSky.
Use Vega to locate the Keystone in Hercules
In late spring from mid-northern latitudes, you can easily find the brilliant blue-white star Vega in the eastern sky at dusk and nightfall. And this star, which lies in the constellation Lyra the Harp, acts as your guide star to the Keystone, a wedge-shaped pattern of four stars in neighboring constellation Hercules.
Look for the Keystone asterism – star pattern – to the upper right of Vega. If you hold your fist at arm’s length, it’ll easily fit between Vega and the Keystone.
Also, you can locate the Keystone by using Vega in conjunction with the brilliant yellow-orange star Arcturus, in Boötes the Herdsman. From mid-northern latitudes this time of year, Arcturus is found quite high in the eastern sky at nightfall. Then, by late evening, Arcturus moves high overhead. The Keystone is found about 1/3 of the way from Vega to Arcturus.
As darkness falls, look for the Keystone in Hercules to the upper right of the brilliant star Vega. Chart via EarthSky.
Most likely, you’ll need binoculars to see the Hercules cluster. Sharp-eyed people can see it with the unaided eye in a dark, transparent sky. Through binoculars, this cluster looks like a dim smudge or a somewhat fuzzy star. However, a telescope begins to resolve this faint fuzzy object into what it really is: a huge globe-shaped stellar city populated with hundreds of thousands of stars!
The Keystone and the Hercules cluster will swing high overhead after midnight, and are found in the western sky before dawn.
Can you find the Keystone on this chart? See the compact grouping of 4 stars at the center of Hercules? That’s it. Note the whereabouts of Messier 13 within the Keystone pattern. Also, above the Keystone is another globular cluster, M92. It’s a bit smaller and dimmer than M13, but also easy to pick up in binoculars or a telescope. Image via International Astronomical Union/ Sky & Telescope/ Wikimedia Commons (CC BY 3.0).
Photos of M13 from EarthSky Community Photos
View at EarthSky Community Photos. | Steven Bellavia in Surry, Virginia, made this comparison of 2 famous globular star clusters on April 17, 2026. Steven wrote: “A large and a giant globular cluster: M13 and Omega Centauri (NGC 5139), imaged with the same gear on the same night.” Steven told us that M13 – the cluster on the left, about 22,000 light-years away – contains approximately 400,000 stars and takes up about 0.36 degrees of sky. Omega Centauri, aka NGC 5139, is a giant globular cluster. It’s on the right in this composite. It contains 10 million stars and takes up about 0.6 degrees of sky, larger than a full moon seen from Earth. It is 17,000 light years away. Thank you, Steven!View at EarthSky Community Photos. | Tameem Altameemi in the United Arab Emirates (UAE), captured this telescopic view of the great Hercules Cluster on April 26, 2025. Tameem wrote: “This image features the beautiful globular cluster Messier 13, also historically known as the Al-Jathi Cluster. Located in the constellation Hercules, M13 lies about 22,200 light-years away from Earth and has an estimated age of 11.65 billion years. It contains several hundred thousand ancient stars, densely packed into a region about 213 light-years across. In the same field of view, the spiral galaxy NGC 6207 and the faint active galaxy IC 4617 are visible.” Thank you, Tameem!View at EarthSky Community Photos. | Tom Cofer in Lakewood Ranch, Florida, captured this telescopic view of Messier 13, the Great Globular Cluster in Hercules, on March 14, 2025. Tom wrote: “A snow globe of stars!” Thank you, Tom!
Finding the Hercules Cluster from Southern Latitudes
The great globular cluster M13 is also visible for Southern Hemisphere viewers, although it never climbs especially high above the horizon and never becomes as prominent as it does for observers farther north. Like Northern Hemisphere observers, southern observers require dark skies to glimpse a very faint M13 with the unaided eye. Through binoculars it appears as a faint hazy patch, while telescopes begin to resolve its densely packed population of ancient stars.
M13’s home constellation Hercules becomes visible during late autumn and is best placed during winter nights. You can still find Hercules’ Keystone by using the bright star Vega, low in the northeastern sky, to guide the way west. Because Hercules remains low above the northern horizon from southern latitudes, a clear northern horizon and dark skies greatly improve the view. Even so, the Keystone can still be recognised as a compact quadrilateral pattern west (or left) of Vega.
M13 competes with the Southern Hemisphere’s own spectacular globular clusters, particularly Omega Centauri and 47 Tucanae. Both appear much larger and brighter from southern latitudes, often climbing high overhead, and provide a striking comparison to the Hercules Cluster. Nonetheless, M13 is a worthwhile target for Southern Hemisphere observers to seek out.
Bottom line: Let the bright star Vega guide you to a famous star pattern in Hercules – called the Keystone – and then to the Hercules cluster, aka M13, a famous globular star cluster.
Meet the mammal that smells like popcorn: the binturong. Image via GabruPawPixels/ Pixabay.
Imagine walking through a Southeast Asian rainforest and catching the unmistakable scent of warm buttered popcorn drifting through the trees. Hmm … is there a popcorn stand in the middle of the forest? The source is likely something far stranger: a shaggy, whiskered mammal with a curling tail and the face of an animal you can’t quite identify.
Meet the binturong, sometimes called the “bearcat”, though it is neither a bear nor a cat. It has dark fur, bright eyes and travels high through the forest canopy with slow, deliberate movements. There is only one species of binturong in the world. And the deeper scientists look into this creature, the more surprising it becomes.
What does a binturong look like?
At first glance, a binturong looks like several animals stitched together.
It has the stocky body of a small bear, long whiskers like a cat and shaggy black fur that often appears slightly frosted at the tips. An adult can grow up to 3 feet (about 90 centimeters) in body length, with an equally impressive bushy tail.
But perhaps the binturong’s most remarkable feature is that its tail is prehensile, meaning it can grip branches like an extra limb. This is something only a handful of carnivorous mammals can do. As the binturong climbs through the treetops, its tail acts almost like a built-in safety rope, helping the animal balance and move among branches.
Its long whiskers might be just as important. Since binturongs are mostly active at night, these highly sensitive whiskers help them sense nearby branches and move through the canopy in the dark.
Its ears are small and rounded, often decorated with tufts of fur, giving the animal a permanently curious expression.
Shaggy, whiskered and perfectly at ease in the treetops, the binturong is one of the few carnivorous mammals with a tail strong enough to grip branches. Image via Kristin Faye/ Pexels.
A life above the forest floor
Binturongs live in the tropical forests of South and Southeast Asia, from India and Nepal to Indonesia and the Philippines. But spotting one in the wild is not easy.
These animals spend much of their lives high in the forest canopy and are mostly active at night. Rather than leaping dramatically through the trees, binturongs tend to move slowly and carefully, climbing branch by branch with surprising confidence.
That relaxed attitude becomes especially clear during the day, when binturongs have occasionally been spotted lounging on branches and quietly basking in the sun — as if rainforest life comes with no particular sense of hurry.
Although classified as carnivores, they have an unexpectedly fruit-heavy diet. Their favorite food is figs, which can make up a large part of what they eat. But they are not picky diners. Binturongs may also snack on birds, fish, insects, eggs and small mammals when the opportunity arises.
Their appetite for fruit makes them important forest helpers. After eating, they spread seeds across the rainforest through their droppings, helping new plants grow. In some forests, scientists consider them key seed dispersers.
These animals move slowly in the rainforest canopy of South and Southeast Asia, but they do so with confidence, as they are amazing climbers. Image via Marjonhorn/ Pixabay.
Why does a binturong smell like popcorn?
Perhaps the binturong’s strangest claim to fame is not what it looks like, but what it smells like.
Many people describe its scent as freshly popped popcorn, warm corn chips or even buttered bread drifting through the forest canopy. It is an unexpectedly pleasant aroma for such an elusive rainforest animal. But the source is far less appetizing.
The smell comes from a chemical compound found in its urine called 2-acetyl-1-pyrroline. It’s the same molecule responsible for the scent of popcorn and freshly baked bread.
This surprising “snack aroma” is actually part of how this animal communicates. Binturongs use scent-marking as they move through the trees, leaving invisible messages along branches that may signal territory, announce their presence or even help attract a mate. In a dense rainforest where visibility is limited, smell can work almost like a calling card.
So if you think you smell popcorn in a rainforest, it might be worth wondering who has just passed through …
Can you smell it? Is it popcorn? Or … a binturong? Image via Jakafp/ Pixabay.
Curious facts about the binturong
The more you learn about binturongs, the stranger they seem.
Despite being called “bearcats,” they belong to neither group. They are unique members of the civet family (Viverridae). There is only one species of binturong in the world.
They can also be surprisingly vocal. Binturongs may chuckle, purr, snort or even make sounds resembling soft giggles, depending on their mood.
And while they often appear calm and slightly clumsy, they are skilled climbers. Their strong claws and grasping tail allow them to descend trees headfirst – no easy task for such a heavy-bodied mammal.
Binturongs know how to relax. Here they are, sunbathing and enjoying themselves after a long night of climbing. Image via Kevinsphotos/ Pixabay.
Baby binturongs are tiny tree-dwellers
Life begins in the dark for a newborn binturong, which is born blind and relies entirely on its mother before it’s strong enough to climb.
Binturongs usually arrive in small litters of one to three, nestled in a hidden nest high above the forest floor. For the first weeks, their world is limited to warmth, scent and sound, as their bodies slowly develop the coordination needed for life in the canopy.
As they grow, their movements become more deliberate. What begins as cautious exploration soon turns into practice climbs through branches, guided by a mother who stays close and attentive.
Unlike some solitary mammals, young binturongs may remain with their mother for an extended period, gradually learning the slow, careful way of moving that defines their species. Their grasping tail, which will one day help them move with confidence through the treetops, starts out as just another untrained limb.
By the time they are fully independent, they already carry the habits of the canopy: steady, deliberate and always a little unhurried.
Look at these cubs at Perth Zoo.
Are binturongs endangered?
The binturong is currently considered vulnerable by the International Union for Conservation of Nature.
Its biggest threats are habitat loss from deforestation, the illegal wildlife trade and hunting in some regions. As tropical forests disappear, the quiet pathways binturongs use through the canopy become fragmented.
And that would be a loss not only for the rainforest, but for the rest of us too.
After all, few animals remind us quite so vividly that nature still holds surprises: creatures that smell like popcorn, climb using their tails and quietly help forests grow, all while remaining hidden among the leaves.
Though carnivores, they delight in fruit and, in their quiet way, help the forest bloom — and we would feel their absence just as much as the forest would. Image via Magda-Ehlers/ Pexels.
Bottom line: The binturong is a strange mammal that smells like popcorn, lives high in the trees and quietly helps tropical forests grow.
Meet the mammal that smells like popcorn: the binturong. Image via GabruPawPixels/ Pixabay.
Imagine walking through a Southeast Asian rainforest and catching the unmistakable scent of warm buttered popcorn drifting through the trees. Hmm … is there a popcorn stand in the middle of the forest? The source is likely something far stranger: a shaggy, whiskered mammal with a curling tail and the face of an animal you can’t quite identify.
Meet the binturong, sometimes called the “bearcat”, though it is neither a bear nor a cat. It has dark fur, bright eyes and travels high through the forest canopy with slow, deliberate movements. There is only one species of binturong in the world. And the deeper scientists look into this creature, the more surprising it becomes.
What does a binturong look like?
At first glance, a binturong looks like several animals stitched together.
It has the stocky body of a small bear, long whiskers like a cat and shaggy black fur that often appears slightly frosted at the tips. An adult can grow up to 3 feet (about 90 centimeters) in body length, with an equally impressive bushy tail.
But perhaps the binturong’s most remarkable feature is that its tail is prehensile, meaning it can grip branches like an extra limb. This is something only a handful of carnivorous mammals can do. As the binturong climbs through the treetops, its tail acts almost like a built-in safety rope, helping the animal balance and move among branches.
Its long whiskers might be just as important. Since binturongs are mostly active at night, these highly sensitive whiskers help them sense nearby branches and move through the canopy in the dark.
Its ears are small and rounded, often decorated with tufts of fur, giving the animal a permanently curious expression.
Shaggy, whiskered and perfectly at ease in the treetops, the binturong is one of the few carnivorous mammals with a tail strong enough to grip branches. Image via Kristin Faye/ Pexels.
A life above the forest floor
Binturongs live in the tropical forests of South and Southeast Asia, from India and Nepal to Indonesia and the Philippines. But spotting one in the wild is not easy.
These animals spend much of their lives high in the forest canopy and are mostly active at night. Rather than leaping dramatically through the trees, binturongs tend to move slowly and carefully, climbing branch by branch with surprising confidence.
That relaxed attitude becomes especially clear during the day, when binturongs have occasionally been spotted lounging on branches and quietly basking in the sun — as if rainforest life comes with no particular sense of hurry.
Although classified as carnivores, they have an unexpectedly fruit-heavy diet. Their favorite food is figs, which can make up a large part of what they eat. But they are not picky diners. Binturongs may also snack on birds, fish, insects, eggs and small mammals when the opportunity arises.
Their appetite for fruit makes them important forest helpers. After eating, they spread seeds across the rainforest through their droppings, helping new plants grow. In some forests, scientists consider them key seed dispersers.
These animals move slowly in the rainforest canopy of South and Southeast Asia, but they do so with confidence, as they are amazing climbers. Image via Marjonhorn/ Pixabay.
Why does a binturong smell like popcorn?
Perhaps the binturong’s strangest claim to fame is not what it looks like, but what it smells like.
Many people describe its scent as freshly popped popcorn, warm corn chips or even buttered bread drifting through the forest canopy. It is an unexpectedly pleasant aroma for such an elusive rainforest animal. But the source is far less appetizing.
The smell comes from a chemical compound found in its urine called 2-acetyl-1-pyrroline. It’s the same molecule responsible for the scent of popcorn and freshly baked bread.
This surprising “snack aroma” is actually part of how this animal communicates. Binturongs use scent-marking as they move through the trees, leaving invisible messages along branches that may signal territory, announce their presence or even help attract a mate. In a dense rainforest where visibility is limited, smell can work almost like a calling card.
So if you think you smell popcorn in a rainforest, it might be worth wondering who has just passed through …
Can you smell it? Is it popcorn? Or … a binturong? Image via Jakafp/ Pixabay.
Curious facts about the binturong
The more you learn about binturongs, the stranger they seem.
Despite being called “bearcats,” they belong to neither group. They are unique members of the civet family (Viverridae). There is only one species of binturong in the world.
They can also be surprisingly vocal. Binturongs may chuckle, purr, snort or even make sounds resembling soft giggles, depending on their mood.
And while they often appear calm and slightly clumsy, they are skilled climbers. Their strong claws and grasping tail allow them to descend trees headfirst – no easy task for such a heavy-bodied mammal.
Binturongs know how to relax. Here they are, sunbathing and enjoying themselves after a long night of climbing. Image via Kevinsphotos/ Pixabay.
Baby binturongs are tiny tree-dwellers
Life begins in the dark for a newborn binturong, which is born blind and relies entirely on its mother before it’s strong enough to climb.
Binturongs usually arrive in small litters of one to three, nestled in a hidden nest high above the forest floor. For the first weeks, their world is limited to warmth, scent and sound, as their bodies slowly develop the coordination needed for life in the canopy.
As they grow, their movements become more deliberate. What begins as cautious exploration soon turns into practice climbs through branches, guided by a mother who stays close and attentive.
Unlike some solitary mammals, young binturongs may remain with their mother for an extended period, gradually learning the slow, careful way of moving that defines their species. Their grasping tail, which will one day help them move with confidence through the treetops, starts out as just another untrained limb.
By the time they are fully independent, they already carry the habits of the canopy: steady, deliberate and always a little unhurried.
Look at these cubs at Perth Zoo.
Are binturongs endangered?
The binturong is currently considered vulnerable by the International Union for Conservation of Nature.
Its biggest threats are habitat loss from deforestation, the illegal wildlife trade and hunting in some regions. As tropical forests disappear, the quiet pathways binturongs use through the canopy become fragmented.
And that would be a loss not only for the rainforest, but for the rest of us too.
After all, few animals remind us quite so vividly that nature still holds surprises: creatures that smell like popcorn, climb using their tails and quietly help forests grow, all while remaining hidden among the leaves.
Though carnivores, they delight in fruit and, in their quiet way, help the forest bloom — and we would feel their absence just as much as the forest would. Image via Magda-Ehlers/ Pexels.
Bottom line: The binturong is a strange mammal that smells like popcorn, lives high in the trees and quietly helps tropical forests grow.
