Along with its close relative, the sapphire, the ruby is a form of the mineral corundum. This mineral is normally drab and gray in color. So a red corundum gemstone is a ruby, and all other colored corundum gemstones – orange, yellow, brown, green, blue, purple, violet, black, and colorless – are sapphires.
And that makes the July birthstone – the ruby – rare and precious. It’s among the most highly prized of gemstones. Large rubies are more difficult to find than large diamonds. And at 9 on the Mohs scale, they’re harder than emerald, topaz, zircon and garnet.
As a result, rubies’ value increases with size more than any other gemstone.
The word ruby comes from the Latin “ruber,” meaning red. This name formerly meant any red stone, including red spinel, red tourmaline, and red garnet.
An oval faceted ruby gemstone. Image via Humanfeather/ Wikipedia.
Sources of the ruby
The Mogok valley of Upper Burma is famous as the source for the finest and rarest rubies of all, known as “pigeon’s blood” for the stones’ intense red color.
Another major source of rubies is Thailand, well-known for dark, brownish-red rubies. Both Thailand and Burma regard the ruby as their national stone.
Giant 11,000-Carat #Ruby Found in #Myanmar Could Be Worth a FortuneMore info and pics: https://ift.tt/geXiL5P…
In much of Asia, people once believed that rubies contained the spark of life – “a deep drop of the heart’s blood of Mother Earth,” according to ancient Eastern legends.
Plus, ancient Asian stories say the ruby is self-luminous. They called it “glowing stone” or “lamp stone.” One story is that an emperor of China used a large ruby to light his chamber, where it glowed as bright as day. Brahmins – Hindu priests of the highest caste – believed that the homes of the gods were lit by enormous emeralds and rubies.
Later, in Greek legends, the ruby symbolized the goddess Aphrodite’s ill-fated love affair with the mortal Adonis.
Raw Tanzanian rubies embedded in a rock matrix. Image via Jarno/ Wikipedia.
Ancient Hindus, Burmese, and Ceylonese regarded sapphires as unripe rubies. Thus, they believed if they buried the sapphire in the ground, it would mature to a rich red ruby.
In the Middle Ages, rubies were thought to bring good health, as well as guard against wicked thoughts, amorous desires, and disputes. Rubies, along with other types of red stones, were said to cure bleeding. And it was believed that the ruby held the power to warn its owner of coming misfortunes, illness, or death, by turning darker in color. It is said that Catherine of Aragon, first wife of King Henry VIII, predicted her downfall when seeing the darkening of her ruby.
Famous rubies?
Because of their rarity, there are very few famous large rubies. In his 13th-century books of his travels, Marco Polo relates the tale of a magnificent gemstone – believed to be a ruby nine inches long and as thick as a man’s arm – belonging to the king of Ceylon. Kublai Khan, the emperor of China, offered an entire city in exchange for the enormous stone, to which the king of Ceylon replied that he would never part with his prize for all the treasures of the world.
Many famous rubies in history turned out not to be rubies after all. For example, the famed Timur ruby – given to Queen Victoria in 1851 – was later found to be ruby spinel.
A round faceted ruby. Image via Decym92/ Wikimedia.
Along with its close relative, the sapphire, the ruby is a form of the mineral corundum. This mineral is normally drab and gray in color. So a red corundum gemstone is a ruby, and all other colored corundum gemstones – orange, yellow, brown, green, blue, purple, violet, black, and colorless – are sapphires.
And that makes the July birthstone – the ruby – rare and precious. It’s among the most highly prized of gemstones. Large rubies are more difficult to find than large diamonds. And at 9 on the Mohs scale, they’re harder than emerald, topaz, zircon and garnet.
As a result, rubies’ value increases with size more than any other gemstone.
The word ruby comes from the Latin “ruber,” meaning red. This name formerly meant any red stone, including red spinel, red tourmaline, and red garnet.
An oval faceted ruby gemstone. Image via Humanfeather/ Wikipedia.
Sources of the ruby
The Mogok valley of Upper Burma is famous as the source for the finest and rarest rubies of all, known as “pigeon’s blood” for the stones’ intense red color.
Another major source of rubies is Thailand, well-known for dark, brownish-red rubies. Both Thailand and Burma regard the ruby as their national stone.
Giant 11,000-Carat #Ruby Found in #Myanmar Could Be Worth a FortuneMore info and pics: https://ift.tt/geXiL5P…
In much of Asia, people once believed that rubies contained the spark of life – “a deep drop of the heart’s blood of Mother Earth,” according to ancient Eastern legends.
Plus, ancient Asian stories say the ruby is self-luminous. They called it “glowing stone” or “lamp stone.” One story is that an emperor of China used a large ruby to light his chamber, where it glowed as bright as day. Brahmins – Hindu priests of the highest caste – believed that the homes of the gods were lit by enormous emeralds and rubies.
Later, in Greek legends, the ruby symbolized the goddess Aphrodite’s ill-fated love affair with the mortal Adonis.
Raw Tanzanian rubies embedded in a rock matrix. Image via Jarno/ Wikipedia.
Ancient Hindus, Burmese, and Ceylonese regarded sapphires as unripe rubies. Thus, they believed if they buried the sapphire in the ground, it would mature to a rich red ruby.
In the Middle Ages, rubies were thought to bring good health, as well as guard against wicked thoughts, amorous desires, and disputes. Rubies, along with other types of red stones, were said to cure bleeding. And it was believed that the ruby held the power to warn its owner of coming misfortunes, illness, or death, by turning darker in color. It is said that Catherine of Aragon, first wife of King Henry VIII, predicted her downfall when seeing the darkening of her ruby.
Famous rubies?
Because of their rarity, there are very few famous large rubies. In his 13th-century books of his travels, Marco Polo relates the tale of a magnificent gemstone – believed to be a ruby nine inches long and as thick as a man’s arm – belonging to the king of Ceylon. Kublai Khan, the emperor of China, offered an entire city in exchange for the enormous stone, to which the king of Ceylon replied that he would never part with his prize for all the treasures of the world.
Many famous rubies in history turned out not to be rubies after all. For example, the famed Timur ruby – given to Queen Victoria in 1851 – was later found to be ruby spinel.
A round faceted ruby. Image via Decym92/ Wikimedia.
The Vera C. Rubin Observatory took this 1.7-gigapixel image of a field of stars in the constellation Lupus the Wolf and Centaurus the Centaur. Rubin is unique in its ability to capture both a wide field of view and extremely faint objects. NOIRLab said on June 30, 2026, that the Rubin Observatory has officially begun its 10-year timelapse of the universe: the Legacy Survey of Space and Time (LSST). Image via NSF–DOE Vera C. Rubin Observatory/ NOIRLab/ SLAC/ AURA.
Rubin Observatory begins 10-year timelapse of the universe
Last June, we got our first look at what the Vera C. Rubin Observatory could do. We were wowed by images of galaxies floating in deep space and a video of thousands of never-before-seen asteroids. And now, on June 30, 2026, the Rubin Observatory has officially begun its 10-year-long survey of the night sky: the Legacy Survey of Space and Time (LSST).
Every night for the next decade, Rubin will rapidly scan the sky using the world’s largest digital camera to create an ultra-wide, ultra-high-definition timelapse of our universe. The goal of the survey is:
to create the most comprehensive, cinematic record of the universe in history.
Brian Stone, the National Science Foundation director, said:
Today, we begin filming the greatest cosmic movie ever made.
The image at top (Rubin’s Oceans of Stars Field) comes from this area of the sky in the Southern Hemisphere constellations of Lupus the Wolf and Centaurus the Centaur. Image via E. Slawik/NOIRLab/NSF/AURA/M. Zamani.
A flood of data
The Rubin Observatory acquires about 10 terabytes of data per night. And every time it sees something change in the night sky – whether that be a supernova erupting or an asteroid sailing in front of the background stars – it sends an alert. How many alerts might it produce in one night? As many as 7 million, says NOIRLab.
After 10 years of the survey, astronomers expect a final dataset of billions of objects with trillions of measurements. It will open the gates to a flood of knowledge about the universe. And that information will be available to both scientists and the public.
Rubin Observatory will capture the dynamic nature of our cosmos and reveal unimagined insights into our universe’s biggest mysteries, from our own solar system to the very structure of the universe. By seeking to understand the enigmatic phenomena of dark energy and dark matter, we are not just observing the stars; we are striving to grasp the fundamental laws that govern our existence.
Watch: A week in the life of Rubin Observatory
The Rubin Observatory will build a multicolor map of the universe. This video shows how much of the sky Rubin can scan in a week with its various color filters.
Rubin Observatory by the numbers
Rubin Observatory’s Legacy Survey of Space and Time by the numbers. Image via NSF–DOE Vera C. Rubin Observatory/ NOIRLab/ SLAC/ AURA.Rubin’s repeated recordings of the universe will bring out a wealth of detail in the objects it sees. Combining many images allows astronomers to see more light and get a sharper, more detailed view of the universe. Image via NSF–DOE Vera C. Rubin Observatory/ NOIRLab/ SLAC/ AURA.
Bottom line: The Rubin Observatory has now begun its Legacy Survey of Space and Time. This 10-year survey will create a timelapse record of the universe, from asteroids cruising through our solar system to whirling deep-space galaxies.
The Vera C. Rubin Observatory took this 1.7-gigapixel image of a field of stars in the constellation Lupus the Wolf and Centaurus the Centaur. Rubin is unique in its ability to capture both a wide field of view and extremely faint objects. NOIRLab said on June 30, 2026, that the Rubin Observatory has officially begun its 10-year timelapse of the universe: the Legacy Survey of Space and Time (LSST). Image via NSF–DOE Vera C. Rubin Observatory/ NOIRLab/ SLAC/ AURA.
Rubin Observatory begins 10-year timelapse of the universe
Last June, we got our first look at what the Vera C. Rubin Observatory could do. We were wowed by images of galaxies floating in deep space and a video of thousands of never-before-seen asteroids. And now, on June 30, 2026, the Rubin Observatory has officially begun its 10-year-long survey of the night sky: the Legacy Survey of Space and Time (LSST).
Every night for the next decade, Rubin will rapidly scan the sky using the world’s largest digital camera to create an ultra-wide, ultra-high-definition timelapse of our universe. The goal of the survey is:
to create the most comprehensive, cinematic record of the universe in history.
Brian Stone, the National Science Foundation director, said:
Today, we begin filming the greatest cosmic movie ever made.
The image at top (Rubin’s Oceans of Stars Field) comes from this area of the sky in the Southern Hemisphere constellations of Lupus the Wolf and Centaurus the Centaur. Image via E. Slawik/NOIRLab/NSF/AURA/M. Zamani.
A flood of data
The Rubin Observatory acquires about 10 terabytes of data per night. And every time it sees something change in the night sky – whether that be a supernova erupting or an asteroid sailing in front of the background stars – it sends an alert. How many alerts might it produce in one night? As many as 7 million, says NOIRLab.
After 10 years of the survey, astronomers expect a final dataset of billions of objects with trillions of measurements. It will open the gates to a flood of knowledge about the universe. And that information will be available to both scientists and the public.
Rubin Observatory will capture the dynamic nature of our cosmos and reveal unimagined insights into our universe’s biggest mysteries, from our own solar system to the very structure of the universe. By seeking to understand the enigmatic phenomena of dark energy and dark matter, we are not just observing the stars; we are striving to grasp the fundamental laws that govern our existence.
Watch: A week in the life of Rubin Observatory
The Rubin Observatory will build a multicolor map of the universe. This video shows how much of the sky Rubin can scan in a week with its various color filters.
Rubin Observatory by the numbers
Rubin Observatory’s Legacy Survey of Space and Time by the numbers. Image via NSF–DOE Vera C. Rubin Observatory/ NOIRLab/ SLAC/ AURA.Rubin’s repeated recordings of the universe will bring out a wealth of detail in the objects it sees. Combining many images allows astronomers to see more light and get a sharper, more detailed view of the universe. Image via NSF–DOE Vera C. Rubin Observatory/ NOIRLab/ SLAC/ AURA.
Bottom line: The Rubin Observatory has now begun its Legacy Survey of Space and Time. This 10-year survey will create a timelapse record of the universe, from asteroids cruising through our solar system to whirling deep-space galaxies.
On June 30, 1908, the largest asteroid impact in recorded history occurred on a warm summer morning in a remote part of Siberia, Russia. Now, we observe Asteroid Day each year on June 30, on the anniversary of what’s now known as the Tunguska explosion.
The explosion happened over sparsely populated forestland north of the Podkamennaya Tunguska River, in what is present-day Krasnoyarsk Krai.
The blast released enough energy to kill reindeer and flatten an estimated 80 million trees over an area of 830 square miles (2,150 square km). Witnesses reported seeing a bluish light nearly as bright as the sun moving across the sky. They said a flash and a sound similar to artillery fire followed the fireball. And, according to the American Physical Society, a powerful shockwave broke windows hundreds of miles away, knocking people off their feet.
Yet, ultimately, decades passed before anyone could explain the event.
The approximate location of the Tunguska event of 1908 in Siberia, Russia. Image via Bobby D. Bryant/ Wikimedia Commons (CC BY-SA 3.0).
Tunguska explosion: One of the largest in recorded history
A mysterious aspect of the Tunguska event was that, surprisingly, no one ever found a crater. But even without a crater, scientists still categorized it as an impact event. They now believe the incoming object never struck Earth. Instead, it exploded in the atmosphere, causing what’s known as an air burst. This type of atmospheric explosion was still enough to cause massive damage to the forest in the region.
Scientists determined the object was most likely a stony asteroid approximately 165-260 feet (50-80 m) in diameter, traveling at a speed of about 33,500 miles per hour (54,000 kph) and exploded 3 to 6 miles (5 to 10 km) above Earth’s surface.
The Tunguska explosion was equal to about 4 megatons of TNT. That would make it 250 times more powerful than the atom bomb dropped on Hiroshima.
Fallen trees from the 1908 Tunguska explosion at Tunguska in Siberia. It wasn’t until 1927 that Russian scientists – led by Leonid Kulik – were finally able to get to the scene. Image via Leonid Kulik/ Wikipedia.
Understanding the Tunguska explosion
Why did it take so long for scientists to understand what caused the Tunguska event? It took almost two decades for the first scientific expedition to reach this remote site in central Siberia. The region was extremely isolated, with no roads, railways or nearby settlements, making access possible only through long and difficult expeditions across the taiga.
This delay was further extended by major historical disruptions, including World War I, the Russian Revolution and the Russian Civil War, which made large-scale scientific travel and funding nearly impossible for many years.
It was not until 1927 that the first major scientific expedition, led by Leonid Kulik, finally reached the site. By then, much of the immediate physical evidence had already degraded or disappeared due to the passage of time and natural regeneration of the forest.
As a result of the delayed investigation and the lack of typical impact evidence such as a crater or large meteorite fragments, early interpretations remained uncertain, allowing speculative explanations to emerge before the true nature of the event was eventually understood. Some concocted wild theories to explain the Tunguska event. People claimed a stricken alien spacecraft caused the destruction. Later, they pointed to a mini-black-hole or a particle of antimatter.
The truth is just as interesting, and perhaps more terrifying … because it can happen again.
Photo of an air burst, in this case from a U.S. Navy submarine-launched Tomahawk cruise missile. A similar kind of air burst from an incoming asteroid flattened the trees in Siberia in 1908. Image via Wikimedia Commons.
The Chelyabinsk meteor impact
Interestingly, the Tunguska event basically did happen again with the Chelyabinsk meteor, 105 years later. On February 15, 2013, a similar – although smaller – airburst occurred over the city of Chelyabinsk, Russia, 1,500 miles (2,400 km) to the west of Tunguska.
Deborah Byrd :
Vapor trail left by the Chelyabinsk meteor, as captured by Flickr user Alex Alishevskikh.
The Chelyabinsk event provided vital clues as to what happened during the Tunguska event. As NASA explained, new evidence arrived to help solve the mystery of Tunguska:
This highly documented fireball created an opportunity for researchers to apply modern computer modeling techniques to explain what was seen, heard and felt.
The models were used with video observations of the fireball and maps of the damage on the ground to reconstruct the original size, motion and speed of the Chelyabinsk object. The resulting interpretation is that Chelyabinsk was most likely a stony asteroid the size of a five-story building [50–70 feet or 15–21 meters] that broke apart 15 miles (24 kilometers) above the ground. This generated a shock wave equivalent to a 550-kiloton explosion. The explosion’s shockwave blew out roughly a million windows and injured more than a thousand people. Fortunately, the force of the explosion was not enough to knock down trees or structures.
Per current understanding of the asteroid population, an object like the Chelyabinsk meteor can impact Earth every 10 to 100 years on average.
Chelyabinsk and Tunguska, in relation to the Empire State Building and the Eiffel Tower. Image via Phoenix CZE/ Wikimedia Commons (CC BY-SA 4.0).
Studying the Tunguska explosion to prepare for future events
In 2019, scientists published new research about the Tunguska event in a series of papers in a special issue of the journal Icarus. A workshop held at NASA’s Ames Research Center in Silicon Valley and sponsored by the NASA Planetary Defense Coordination Office inspired the research.
The theme of the workshop was Reexamining the astronomical cold case of the 1908 Tunguska impact event.
In recent decades – due to the Tunguska event and other smaller impacts – astronomers have come to take the possibility of catastrophic comet and asteroid impacts seriously. They now have observing programs to watch for near-Earth objects (NEOs). At regular meetings they discuss what might happen if we do find a large object on a collision course with Earth.
DART’s successful asteroid mission
DART – the Double Asteroid Redirection Test – was a huge hit, quite literally. The spacecraft smashed into an asteroid moon – called Didymos B, or Dimorphos – on September 26, 2022. The goal was to prove that we can send a spacecraft to push an asteroid slightly in its orbit. It was practice for a possible future scenario in which we find a hazardous asteroid barreling toward Earth. NASA said on October 11, 2022, that analysis of data obtained from the DART mission shows the spacecraft did, indeed, successfully alter the orbit of Dimorphos.
ESA’s Hera mission launched on October 7, 2024. The Hera mission will journey to Didymos to study DART’s impact. It’s expected to reach Didymos in late December 2026.
Because there are so few observed cases, a lot of uncertainty remains about how large asteroids break up in the atmosphere and how much damage they could cause on the ground. However, recent advancements in computational models, along with analyses of the Chelyabinsk and other meteor events, are helping to improve our understanding of these factors so that we can better evaluate potential asteroid threats in the future.
Tunguska is the largest cosmic impact witnessed by modern humans. It also is characteristic of the sort of impact we are likely to have to protect against in the future.
Bottom line: The Tunguska explosion on June 30, 1908, was the largest asteroid impact in recorded history. It flattened 830 square miles (2,150 square km) of Siberian forest. Researchers are preparing for future Tunguska-sized events.
On June 30, 1908, the largest asteroid impact in recorded history occurred on a warm summer morning in a remote part of Siberia, Russia. Now, we observe Asteroid Day each year on June 30, on the anniversary of what’s now known as the Tunguska explosion.
The explosion happened over sparsely populated forestland north of the Podkamennaya Tunguska River, in what is present-day Krasnoyarsk Krai.
The blast released enough energy to kill reindeer and flatten an estimated 80 million trees over an area of 830 square miles (2,150 square km). Witnesses reported seeing a bluish light nearly as bright as the sun moving across the sky. They said a flash and a sound similar to artillery fire followed the fireball. And, according to the American Physical Society, a powerful shockwave broke windows hundreds of miles away, knocking people off their feet.
Yet, ultimately, decades passed before anyone could explain the event.
The approximate location of the Tunguska event of 1908 in Siberia, Russia. Image via Bobby D. Bryant/ Wikimedia Commons (CC BY-SA 3.0).
Tunguska explosion: One of the largest in recorded history
A mysterious aspect of the Tunguska event was that, surprisingly, no one ever found a crater. But even without a crater, scientists still categorized it as an impact event. They now believe the incoming object never struck Earth. Instead, it exploded in the atmosphere, causing what’s known as an air burst. This type of atmospheric explosion was still enough to cause massive damage to the forest in the region.
Scientists determined the object was most likely a stony asteroid approximately 165-260 feet (50-80 m) in diameter, traveling at a speed of about 33,500 miles per hour (54,000 kph) and exploded 3 to 6 miles (5 to 10 km) above Earth’s surface.
The Tunguska explosion was equal to about 4 megatons of TNT. That would make it 250 times more powerful than the atom bomb dropped on Hiroshima.
Fallen trees from the 1908 Tunguska explosion at Tunguska in Siberia. It wasn’t until 1927 that Russian scientists – led by Leonid Kulik – were finally able to get to the scene. Image via Leonid Kulik/ Wikipedia.
Understanding the Tunguska explosion
Why did it take so long for scientists to understand what caused the Tunguska event? It took almost two decades for the first scientific expedition to reach this remote site in central Siberia. The region was extremely isolated, with no roads, railways or nearby settlements, making access possible only through long and difficult expeditions across the taiga.
This delay was further extended by major historical disruptions, including World War I, the Russian Revolution and the Russian Civil War, which made large-scale scientific travel and funding nearly impossible for many years.
It was not until 1927 that the first major scientific expedition, led by Leonid Kulik, finally reached the site. By then, much of the immediate physical evidence had already degraded or disappeared due to the passage of time and natural regeneration of the forest.
As a result of the delayed investigation and the lack of typical impact evidence such as a crater or large meteorite fragments, early interpretations remained uncertain, allowing speculative explanations to emerge before the true nature of the event was eventually understood. Some concocted wild theories to explain the Tunguska event. People claimed a stricken alien spacecraft caused the destruction. Later, they pointed to a mini-black-hole or a particle of antimatter.
The truth is just as interesting, and perhaps more terrifying … because it can happen again.
Photo of an air burst, in this case from a U.S. Navy submarine-launched Tomahawk cruise missile. A similar kind of air burst from an incoming asteroid flattened the trees in Siberia in 1908. Image via Wikimedia Commons.
The Chelyabinsk meteor impact
Interestingly, the Tunguska event basically did happen again with the Chelyabinsk meteor, 105 years later. On February 15, 2013, a similar – although smaller – airburst occurred over the city of Chelyabinsk, Russia, 1,500 miles (2,400 km) to the west of Tunguska.
Deborah Byrd :
Vapor trail left by the Chelyabinsk meteor, as captured by Flickr user Alex Alishevskikh.
The Chelyabinsk event provided vital clues as to what happened during the Tunguska event. As NASA explained, new evidence arrived to help solve the mystery of Tunguska:
This highly documented fireball created an opportunity for researchers to apply modern computer modeling techniques to explain what was seen, heard and felt.
The models were used with video observations of the fireball and maps of the damage on the ground to reconstruct the original size, motion and speed of the Chelyabinsk object. The resulting interpretation is that Chelyabinsk was most likely a stony asteroid the size of a five-story building [50–70 feet or 15–21 meters] that broke apart 15 miles (24 kilometers) above the ground. This generated a shock wave equivalent to a 550-kiloton explosion. The explosion’s shockwave blew out roughly a million windows and injured more than a thousand people. Fortunately, the force of the explosion was not enough to knock down trees or structures.
Per current understanding of the asteroid population, an object like the Chelyabinsk meteor can impact Earth every 10 to 100 years on average.
Chelyabinsk and Tunguska, in relation to the Empire State Building and the Eiffel Tower. Image via Phoenix CZE/ Wikimedia Commons (CC BY-SA 4.0).
Studying the Tunguska explosion to prepare for future events
In 2019, scientists published new research about the Tunguska event in a series of papers in a special issue of the journal Icarus. A workshop held at NASA’s Ames Research Center in Silicon Valley and sponsored by the NASA Planetary Defense Coordination Office inspired the research.
The theme of the workshop was Reexamining the astronomical cold case of the 1908 Tunguska impact event.
In recent decades – due to the Tunguska event and other smaller impacts – astronomers have come to take the possibility of catastrophic comet and asteroid impacts seriously. They now have observing programs to watch for near-Earth objects (NEOs). At regular meetings they discuss what might happen if we do find a large object on a collision course with Earth.
DART’s successful asteroid mission
DART – the Double Asteroid Redirection Test – was a huge hit, quite literally. The spacecraft smashed into an asteroid moon – called Didymos B, or Dimorphos – on September 26, 2022. The goal was to prove that we can send a spacecraft to push an asteroid slightly in its orbit. It was practice for a possible future scenario in which we find a hazardous asteroid barreling toward Earth. NASA said on October 11, 2022, that analysis of data obtained from the DART mission shows the spacecraft did, indeed, successfully alter the orbit of Dimorphos.
ESA’s Hera mission launched on October 7, 2024. The Hera mission will journey to Didymos to study DART’s impact. It’s expected to reach Didymos in late December 2026.
Because there are so few observed cases, a lot of uncertainty remains about how large asteroids break up in the atmosphere and how much damage they could cause on the ground. However, recent advancements in computational models, along with analyses of the Chelyabinsk and other meteor events, are helping to improve our understanding of these factors so that we can better evaluate potential asteroid threats in the future.
Tunguska is the largest cosmic impact witnessed by modern humans. It also is characteristic of the sort of impact we are likely to have to protect against in the future.
Bottom line: The Tunguska explosion on June 30, 1908, was the largest asteroid impact in recorded history. It flattened 830 square miles (2,150 square km) of Siberian forest. Researchers are preparing for future Tunguska-sized events.
The boat-billed heron is a startling creature! And behind its looks lie some powerful adaptations. Image via StockMediaSeller/ Shutterstock.
The boat-billed heron is one of those creatures that makes you look twice. The first time, to make sure you’re not seeing things. The second, to figure out what exactly you’re looking at.
This bird’s enormous bill seems far too large for its head. Its eyes are strikingly oversized. And its crest gives it the appearance of a rock star who has spent a little too much time in the mangroves. Yet none of this is accidental. Every one of these features serves a specific purpose and forms part of one of the most remarkable adaptations among water birds.
Heron, what a big mouth you have!
The boat-billed heron’s most distinctive feature is the enormous bill that gives the species its name. It is so broad and deep that it resembles a small boat turned upside down over its face. This wide-mouthed creature could easily have replaced the wolf in Little Red Riding Hood!
Compared with other herons, the size difference is so striking that it’s hard to believe they belong to the same group of birds.
And this bill is far more than a decorative feature. It’s actually an extraordinarily effective hunting tool. Its large surface area helps the bird to catch fish, crustaceans, frogs and other aquatic animals.
What is even more fascinating is that much of its anatomy appears to have evolved around this structure. The skull, neck and muscles all work together to support and control one of the most specialized hunting tools found in the wetlands of the Americas.
Seen head-on, the bill occupies such a large portion of the head that it’s hard to imagine how the rest of the bird managed to fit around it.
These birds have oversized bills, which are highly specialized hunting tools. They are perfectly adapted for catching aquatic prey. Image via Daniel Lloyd Blunk-Fernández/ Unsplash.
A head built to support an impressive tool
Having one of the most oversized bills in the heron world comes with certain anatomical challenges. Evolution has invested a lot of this bird’s resources into this feature.
The boat-billed heron’s skull is sturdier than you might expect for a bird of its size, and its neck muscles are especially well developed to support the weight of the head. In a sense, much of its anatomy is organized around a single mission: handling that extraordinary bill efficiently.
A bill this large needs a strong neck and a sturdy skull to support it. Image via Katharina Kammermann/ Pixabay.
The eyes of a nocturnal hunter
While many herons are mainly active during the day, the boat-billed heron prefers to emerge after dark.
To do so, it relies on exceptionally large eyes capable of making the most of the limited available light. Thanks to this adaptation, it can detect movement on the water’s surface when most other birds are already at rest.
These huge eyes give it such an unusual expression that many people compare it to an owl, despite the fact that the two are not closely related.
Unlike most herons, the boat-billed heron hunts at night. Its huge eyes help it spot prey in the dark. Image via Goszton/ Pexels.
A hairstyle worthy of a rock star
And if the bill and eyes are not enough to attract attention, the boat-billed heron also sports an elegant crest made up of long, dark feathers that grow from the back of the head. More than a few people would envy such impressive “hair”!
These feathers can lie smoothly backward or become more prominent when the bird is alert. The result is a slightly tousled appearance that adds to its eccentric look. Both males and females possess this striking crest, and during courtship it may play an important role in their visual displays.
Few birds manage to look dignified, comical and powerful all at once, but this species pulls it off effortlessly.
Its long, dark crest adds even more personality, making this already unusual bird look both elegant and rebellious. Image via Christian Musat/ Shutterstock.
The art of disappearing into the mangroves
Despite its eye-catching appearance, the boat-billed heron is surprisingly difficult to spot.
It inhabits tropical wetlands, particularly mangroves, estuaries, coastal lagoons and the banks of slow-moving rivers. Its range extends across much of tropical America, from southern Mexico through Central America and into large areas of South America.
These habitats are not only its home but also one of its greatest advantages. Submerged roots, deep shadows and tangled vegetation create the perfect setting for both hunting and hiding.
Its plumage – a blend of grays, blacks and browns – blends seamlessly into this environment. During the day, it remains motionless among branches and roots, letting its camouflage do the work as it observes from a hidden vantage point.
It’s likely that many have passed within just a few feet of a boat-billed heron without ever noticing it.
Despite its unusual appearance, the boat-billed heron is remarkably hard to spot. Its camouflage allows it to disappear among mangroves and riverside vegetation. Image via Goszton/ Pexels.
A patient and methodical hunter
The hunting strategy of this species relies more on patience than speed.
Rather than constantly patrolling the shoreline in search of food, it often stands still for long periods, waiting for the right opportunity. When prey comes close enough, it strikes with remarkable speed and precision.
Most of its activity takes place at dusk and during the night. While other water birds become less active, the boat-billed heron uses its enormous eyes to detect even the slightest movement in shallow water.
It will often remain motionless for minutes at a time, carefully watching the surface. Once it detects potential prey, it reacts with impressive speed. It uses its huge bill like a trap, snapping it shut around fish, amphibians or crustaceans before they have a chance to react.
Its diet includes small fish, frogs, aquatic insects, crabs, shrimp and other wetland creatures. It is an opportunistic hunter, capable of taking advantage of almost any food source it encounters in shallow waters.
Patience is its greatest hunting skill. It stands perfectly still until prey comes close, then strikes with lightning-fast precision. Image via Goszton/ Pexels.
A flight silhouette like no other
In flight, it adopts the typical heron posture, with its neck tucked back into a characteristic curve.
There is, however, one detail that sets it apart immediately: its enormous head. Even from a distance, its silhouette looks unusual because the front part of the body appears disproportionately large compared with the rest.
Chicks are born looking outlandish
Boat-billed heron chicks look like unfinished miniature versions of the adults.
From a very young age, they already possess a surprisingly large bill for their size, giving them a disproportionate and somewhat comical appearance. As they grow, this feature becomes increasingly pronounced until it reaches the mighty dimensions of adult birds.
Both parents build the nest, incubate the eggs and later feed the chicks through regurgitation, a common practice among many water birds.
The bird that puzzled scientists
For a long time, ornithologists struggled to determine exactly where this species belonged on the avian evolutionary tree.
Its appearance was so different from that of other herons that some specialists even suggested it deserved its own classification. Although modern studies have clarified its evolutionary relationships, it remains one of the most distinctive species in the entire group.
And perhaps that is the best way to describe it: a heron that looks startlingly unlike a heron.
Scientists once questioned whether this was really a heron. We can see why! Image via Goszton/ Pexels.
Bottom line: The boat-billed heron is a striking example of evolution going big. This creature has an oversized bill, large eyes, and an anatomy shaped around a specialized hunting tool.
The boat-billed heron is a startling creature! And behind its looks lie some powerful adaptations. Image via StockMediaSeller/ Shutterstock.
The boat-billed heron is one of those creatures that makes you look twice. The first time, to make sure you’re not seeing things. The second, to figure out what exactly you’re looking at.
This bird’s enormous bill seems far too large for its head. Its eyes are strikingly oversized. And its crest gives it the appearance of a rock star who has spent a little too much time in the mangroves. Yet none of this is accidental. Every one of these features serves a specific purpose and forms part of one of the most remarkable adaptations among water birds.
Heron, what a big mouth you have!
The boat-billed heron’s most distinctive feature is the enormous bill that gives the species its name. It is so broad and deep that it resembles a small boat turned upside down over its face. This wide-mouthed creature could easily have replaced the wolf in Little Red Riding Hood!
Compared with other herons, the size difference is so striking that it’s hard to believe they belong to the same group of birds.
And this bill is far more than a decorative feature. It’s actually an extraordinarily effective hunting tool. Its large surface area helps the bird to catch fish, crustaceans, frogs and other aquatic animals.
What is even more fascinating is that much of its anatomy appears to have evolved around this structure. The skull, neck and muscles all work together to support and control one of the most specialized hunting tools found in the wetlands of the Americas.
Seen head-on, the bill occupies such a large portion of the head that it’s hard to imagine how the rest of the bird managed to fit around it.
These birds have oversized bills, which are highly specialized hunting tools. They are perfectly adapted for catching aquatic prey. Image via Daniel Lloyd Blunk-Fernández/ Unsplash.
A head built to support an impressive tool
Having one of the most oversized bills in the heron world comes with certain anatomical challenges. Evolution has invested a lot of this bird’s resources into this feature.
The boat-billed heron’s skull is sturdier than you might expect for a bird of its size, and its neck muscles are especially well developed to support the weight of the head. In a sense, much of its anatomy is organized around a single mission: handling that extraordinary bill efficiently.
A bill this large needs a strong neck and a sturdy skull to support it. Image via Katharina Kammermann/ Pixabay.
The eyes of a nocturnal hunter
While many herons are mainly active during the day, the boat-billed heron prefers to emerge after dark.
To do so, it relies on exceptionally large eyes capable of making the most of the limited available light. Thanks to this adaptation, it can detect movement on the water’s surface when most other birds are already at rest.
These huge eyes give it such an unusual expression that many people compare it to an owl, despite the fact that the two are not closely related.
Unlike most herons, the boat-billed heron hunts at night. Its huge eyes help it spot prey in the dark. Image via Goszton/ Pexels.
A hairstyle worthy of a rock star
And if the bill and eyes are not enough to attract attention, the boat-billed heron also sports an elegant crest made up of long, dark feathers that grow from the back of the head. More than a few people would envy such impressive “hair”!
These feathers can lie smoothly backward or become more prominent when the bird is alert. The result is a slightly tousled appearance that adds to its eccentric look. Both males and females possess this striking crest, and during courtship it may play an important role in their visual displays.
Few birds manage to look dignified, comical and powerful all at once, but this species pulls it off effortlessly.
Its long, dark crest adds even more personality, making this already unusual bird look both elegant and rebellious. Image via Christian Musat/ Shutterstock.
The art of disappearing into the mangroves
Despite its eye-catching appearance, the boat-billed heron is surprisingly difficult to spot.
It inhabits tropical wetlands, particularly mangroves, estuaries, coastal lagoons and the banks of slow-moving rivers. Its range extends across much of tropical America, from southern Mexico through Central America and into large areas of South America.
These habitats are not only its home but also one of its greatest advantages. Submerged roots, deep shadows and tangled vegetation create the perfect setting for both hunting and hiding.
Its plumage – a blend of grays, blacks and browns – blends seamlessly into this environment. During the day, it remains motionless among branches and roots, letting its camouflage do the work as it observes from a hidden vantage point.
It’s likely that many have passed within just a few feet of a boat-billed heron without ever noticing it.
Despite its unusual appearance, the boat-billed heron is remarkably hard to spot. Its camouflage allows it to disappear among mangroves and riverside vegetation. Image via Goszton/ Pexels.
A patient and methodical hunter
The hunting strategy of this species relies more on patience than speed.
Rather than constantly patrolling the shoreline in search of food, it often stands still for long periods, waiting for the right opportunity. When prey comes close enough, it strikes with remarkable speed and precision.
Most of its activity takes place at dusk and during the night. While other water birds become less active, the boat-billed heron uses its enormous eyes to detect even the slightest movement in shallow water.
It will often remain motionless for minutes at a time, carefully watching the surface. Once it detects potential prey, it reacts with impressive speed. It uses its huge bill like a trap, snapping it shut around fish, amphibians or crustaceans before they have a chance to react.
Its diet includes small fish, frogs, aquatic insects, crabs, shrimp and other wetland creatures. It is an opportunistic hunter, capable of taking advantage of almost any food source it encounters in shallow waters.
Patience is its greatest hunting skill. It stands perfectly still until prey comes close, then strikes with lightning-fast precision. Image via Goszton/ Pexels.
A flight silhouette like no other
In flight, it adopts the typical heron posture, with its neck tucked back into a characteristic curve.
There is, however, one detail that sets it apart immediately: its enormous head. Even from a distance, its silhouette looks unusual because the front part of the body appears disproportionately large compared with the rest.
Chicks are born looking outlandish
Boat-billed heron chicks look like unfinished miniature versions of the adults.
From a very young age, they already possess a surprisingly large bill for their size, giving them a disproportionate and somewhat comical appearance. As they grow, this feature becomes increasingly pronounced until it reaches the mighty dimensions of adult birds.
Both parents build the nest, incubate the eggs and later feed the chicks through regurgitation, a common practice among many water birds.
The bird that puzzled scientists
For a long time, ornithologists struggled to determine exactly where this species belonged on the avian evolutionary tree.
Its appearance was so different from that of other herons that some specialists even suggested it deserved its own classification. Although modern studies have clarified its evolutionary relationships, it remains one of the most distinctive species in the entire group.
And perhaps that is the best way to describe it: a heron that looks startlingly unlike a heron.
Scientists once questioned whether this was really a heron. We can see why! Image via Goszton/ Pexels.
Bottom line: The boat-billed heron is a striking example of evolution going big. This creature has an oversized bill, large eyes, and an anatomy shaped around a specialized hunting tool.
Why is June’s full moon the lowest full moon of 2026 for viewers in the Northern Hemisphere? And why does the same moon ride high in Southern Hemisphere skies? Join EarthSky’s Deborah Byrd as she explores the geometry behind this month’s full moon. Watch in the player above or on YouTube.
When to watch in 2026: The full moon comes on June 29 for the Americas, Europe, and Africa, and on June 30 for Australia, New Zealand, and much of Asia. Same full moon for all of Earth … but different timezones. The crest of this month’s full moon will fall at 23:57 UTC on June 29, 2026. That’s 6:57 p.m. Central Daylight Time in the Americas on June 29. It’s 11:57 a.m. New Zealand Standard Time on June 30. Where to look:Full moons are always opposite the sun. They must be, in order to look full. So every full moon rises in the east just after the sun has set in the west. And full moons reach their highest points in the sky in the middle of the night, when the sun is below your feet. This June 2026 full moon is a micromoon – or particularly distant full moon – in a far part of its orbit from Earth. It’s the last full micromoon of 2026. The June 2026 full moon is noteworthy for its path across our sky. It’s one of the lowest moon paths in decades for the Northern Hemisphere, one of the highest in decades for the Southern Hemisphere. The June full moon can help you locate yourself within the Milky Way galaxy. That’s because it points (more or less) toward the galaxy’s heart.
In 2026, the June full moon is passing through Sagittarius
The center of our Milky Way galaxy lies near the famous Teapot asterism in the constellation Sagittarius the Archer.
The 2026 full Strawberry Moon will lie (more or less) in this direction. So when you are looking toward the June full moon, you’re looking toward the heart of our home galaxy, the Milky Way. Cool, right?
For us in the Northern Hemisphere, this particularly low June full moon might illustrate to you that – as always – the Teapot rides low in our southern sky.
But for the Southern Hemisphere the Teapot – and June’s full moon – ride high! The Southern Hemisphere has a much better view of the direction toward the Milky Way’s center than we do, north of the equator.
By the way, there’s nothing unusual about the full moon pointing toward the galaxy’s heart. The June full moon can lie in front of one of three constellations of the zodiac: Sagittarius, Scorpius the Scorpion or Ophiuchus the Serpent Bearer.
On June 29, June’s full moon – the Strawberry moon – will float among the faint stars of the Teapot asterism in Sagittarius. The moon’s brightness easily overpowers the stars of the Teapot. When you look in this direction, you’re looking, more or less, toward the center of our home galaxy, the Milky Way. Chart via EarthSky.The 2026 June full moon falls on the overnight of June 29 and lies in the constellation Sagittarius. Chart via EarthSky.
The June full moon rides low
As seen from the Northern Hemisphere, the June full moon always rides low. And, as seen from the Southern Hemisphere, the June full moon always rides high. It’s because every full moon must be opposite the sun. It’s only when the moon is opposite the sun that we can see its fully lighted “day” hemisphere.
It’s opposite the sun. So its nighttime path mimics the sun’s daytime arc from six months ago, and six months hence.
This June 29 full moon will occur just eight days after the June solstice, which fell on June 21. So the moon’s trek across the sky, throughout the night around the June 29 full moon, will resemble the path of the December sun: low from the Northern Hemisphere, high from the Southern Hemisphere.
For observers in the Southern Hemisphere, the high arc across the sky of the June full moon closely matches that of the December sun. The arc of the June sun is always much lower than the arc of the June full moon, and matches that of the December full moon. Chart via EarthSky.
The June full moon is the Strawberry Moon
All full moons have names, which come mostly from native American, colonial American or European traditions. Many full moon names correspond to seasons of the year. And, interestingly, the Southern Hemisphere tends to use the Northern Hemisphere’s full moon names, too. That’s probably especially true since the advent of an internet!
We most commonly hear Strawberry Moon for the June full moon. The name is supposed to highlight the time of year when many species of berries ripen, particularly sweet strawberries. In reality, strawberries in the Northern Hemisphere ripen anywhere from April through June, depending on local climate and the variety of berry. That’s a clue to the name’s origin, because berries in northern North America do ripen around June.
Meanwhile, Europe has used the names Honey Moon and Mead Moon for the June full moon. That makes sense because the June full moon always rides so low. And when we look at sky objects nearer to the horizon, we’re looking at them through an extra thickness of Earth’s atmosphere. The extra air creates the golden color of the June full moon. It’s truly honey-colored (and mead is made from honey, too).
Despite its name, the Strawberry Moon isn’t usually pink. In fact, it’s likely to appear more golden in color. The name comes from the strawberry harvest season. And this image was made by ChatGPT.
This June’s full moon is a micromoon
Some moons are supermoons. That is, they’re both full and in a close part of their orbit around Earth. So they’re particularly large, as seen by cameras or measured by special instruments. And they’re extra bright, as seen to the eye and also in the light they cast on the ground.
But the June 2026 full moon is the faint counterpart of a supermoon. It’s a micromoon, or a particularly small full moon, in a far part of its orbit from Earth. It’s the last of three full micromoons in a row in 2026. Apogee – the moon’s most distant point for the month – happens the day before this month’s full moon.
A micromoon can appear up to 14% smaller and 30% fainter than a supermoon. You definitely won’t notice with your eye that it’s any smaller. But will it appear less bright to your eye than a supermoon? Probably not. Supermoons do look noticeably brighter. But part of a supermoon’s brightness is due to the extra light it casts on earthly landscapes. Around the time of a supermoon, you can see moon shadows. A fainter landscape is just harder to notice.
And, like all full moons – micro or super – this June 2026 full moon will shine so brightly that its light will obscure many twinkling stars.
A supermoon appears 14% wider and 30% brighter than a micromoon. Chart via EarthSky.At full moon, the sun, Earth, and moon are aligned with Earth in the middle. The moon’s day side – its fully lighted hemisphere – directly faces us. Chart via EarthSky.
Bottom line: The June full moon – the Strawberry Moon – will occur on the overnight of June 29, 2026, and will lie in front of the Teapot asterism in the constellation Sagittarius.
Why is June’s full moon the lowest full moon of 2026 for viewers in the Northern Hemisphere? And why does the same moon ride high in Southern Hemisphere skies? Join EarthSky’s Deborah Byrd as she explores the geometry behind this month’s full moon. Watch in the player above or on YouTube.
When to watch in 2026: The full moon comes on June 29 for the Americas, Europe, and Africa, and on June 30 for Australia, New Zealand, and much of Asia. Same full moon for all of Earth … but different timezones. The crest of this month’s full moon will fall at 23:57 UTC on June 29, 2026. That’s 6:57 p.m. Central Daylight Time in the Americas on June 29. It’s 11:57 a.m. New Zealand Standard Time on June 30. Where to look:Full moons are always opposite the sun. They must be, in order to look full. So every full moon rises in the east just after the sun has set in the west. And full moons reach their highest points in the sky in the middle of the night, when the sun is below your feet. This June 2026 full moon is a micromoon – or particularly distant full moon – in a far part of its orbit from Earth. It’s the last full micromoon of 2026. The June 2026 full moon is noteworthy for its path across our sky. It’s one of the lowest moon paths in decades for the Northern Hemisphere, one of the highest in decades for the Southern Hemisphere. The June full moon can help you locate yourself within the Milky Way galaxy. That’s because it points (more or less) toward the galaxy’s heart.
In 2026, the June full moon is passing through Sagittarius
The center of our Milky Way galaxy lies near the famous Teapot asterism in the constellation Sagittarius the Archer.
The 2026 full Strawberry Moon will lie (more or less) in this direction. So when you are looking toward the June full moon, you’re looking toward the heart of our home galaxy, the Milky Way. Cool, right?
For us in the Northern Hemisphere, this particularly low June full moon might illustrate to you that – as always – the Teapot rides low in our southern sky.
But for the Southern Hemisphere the Teapot – and June’s full moon – ride high! The Southern Hemisphere has a much better view of the direction toward the Milky Way’s center than we do, north of the equator.
By the way, there’s nothing unusual about the full moon pointing toward the galaxy’s heart. The June full moon can lie in front of one of three constellations of the zodiac: Sagittarius, Scorpius the Scorpion or Ophiuchus the Serpent Bearer.
On June 29, June’s full moon – the Strawberry moon – will float among the faint stars of the Teapot asterism in Sagittarius. The moon’s brightness easily overpowers the stars of the Teapot. When you look in this direction, you’re looking, more or less, toward the center of our home galaxy, the Milky Way. Chart via EarthSky.The 2026 June full moon falls on the overnight of June 29 and lies in the constellation Sagittarius. Chart via EarthSky.
The June full moon rides low
As seen from the Northern Hemisphere, the June full moon always rides low. And, as seen from the Southern Hemisphere, the June full moon always rides high. It’s because every full moon must be opposite the sun. It’s only when the moon is opposite the sun that we can see its fully lighted “day” hemisphere.
It’s opposite the sun. So its nighttime path mimics the sun’s daytime arc from six months ago, and six months hence.
This June 29 full moon will occur just eight days after the June solstice, which fell on June 21. So the moon’s trek across the sky, throughout the night around the June 29 full moon, will resemble the path of the December sun: low from the Northern Hemisphere, high from the Southern Hemisphere.
For observers in the Southern Hemisphere, the high arc across the sky of the June full moon closely matches that of the December sun. The arc of the June sun is always much lower than the arc of the June full moon, and matches that of the December full moon. Chart via EarthSky.
The June full moon is the Strawberry Moon
All full moons have names, which come mostly from native American, colonial American or European traditions. Many full moon names correspond to seasons of the year. And, interestingly, the Southern Hemisphere tends to use the Northern Hemisphere’s full moon names, too. That’s probably especially true since the advent of an internet!
We most commonly hear Strawberry Moon for the June full moon. The name is supposed to highlight the time of year when many species of berries ripen, particularly sweet strawberries. In reality, strawberries in the Northern Hemisphere ripen anywhere from April through June, depending on local climate and the variety of berry. That’s a clue to the name’s origin, because berries in northern North America do ripen around June.
Meanwhile, Europe has used the names Honey Moon and Mead Moon for the June full moon. That makes sense because the June full moon always rides so low. And when we look at sky objects nearer to the horizon, we’re looking at them through an extra thickness of Earth’s atmosphere. The extra air creates the golden color of the June full moon. It’s truly honey-colored (and mead is made from honey, too).
Despite its name, the Strawberry Moon isn’t usually pink. In fact, it’s likely to appear more golden in color. The name comes from the strawberry harvest season. And this image was made by ChatGPT.
This June’s full moon is a micromoon
Some moons are supermoons. That is, they’re both full and in a close part of their orbit around Earth. So they’re particularly large, as seen by cameras or measured by special instruments. And they’re extra bright, as seen to the eye and also in the light they cast on the ground.
But the June 2026 full moon is the faint counterpart of a supermoon. It’s a micromoon, or a particularly small full moon, in a far part of its orbit from Earth. It’s the last of three full micromoons in a row in 2026. Apogee – the moon’s most distant point for the month – happens the day before this month’s full moon.
A micromoon can appear up to 14% smaller and 30% fainter than a supermoon. You definitely won’t notice with your eye that it’s any smaller. But will it appear less bright to your eye than a supermoon? Probably not. Supermoons do look noticeably brighter. But part of a supermoon’s brightness is due to the extra light it casts on earthly landscapes. Around the time of a supermoon, you can see moon shadows. A fainter landscape is just harder to notice.
And, like all full moons – micro or super – this June 2026 full moon will shine so brightly that its light will obscure many twinkling stars.
A supermoon appears 14% wider and 30% brighter than a micromoon. Chart via EarthSky.At full moon, the sun, Earth, and moon are aligned with Earth in the middle. The moon’s day side – its fully lighted hemisphere – directly faces us. Chart via EarthSky.
Bottom line: The June full moon – the Strawberry Moon – will occur on the overnight of June 29, 2026, and will lie in front of the Teapot asterism in the constellation Sagittarius.
The more atmosphere you are peering through, the more stars (or sometimes planets) appear to twinkle. Read below why stars twinkle, but planets do not. Chart by AstroBob. Used with permission.
Stars twinkle, while planets (usually) shine steadily
Stars twinkle because they’re so far away from Earth that, even through large telescopes, they appear only as pinpoints. And it’s easy for Earth’s atmosphere to disturb the pinpoint light of a star. As a star’s light pierces our atmosphere, it’s refracted – causing it to change direction slightly – by the various temperature and density layers in Earth’s atmosphere. You might think of it as the light traveling a zig-zag path to our eyes, instead of the straight path the light would travel if Earth didn’t have an atmosphere.
Astronomers use the term “scintillation” to describe the twinkling of stars.
The twinkling of the stars is called scintillation. Stars are so far away, that they are actually just points of light pic.twitter.com/xcnIKKhYZE
Planets shine more steadily because they’re closer to Earth and so appear not as pinpoints, but as tiny disks in our sky. You can see planets as disks if you look through a telescope, while stars remain pinpoints. Earth’s atmosphere refracts the light from these little disks as it travels toward our eyes. But – while the light from one edge of a planet’s disk might “zig” one way – light from the opposite edge of the disk might be “zagging” in an opposite way. The zigs and zags of light from a planetary disk cancel each other out, and that’s why planets appear to shine steadily.
You might see planets twinkling if you spot them low in the sky. That’s because, in the direction of any horizon, you’re looking through more atmosphere than when you look overhead.
If you could see stars and planets from outer space, both would shine steadily. There would be no atmosphere to disturb the steady streaming of their light.
Can you figure out which objects are stars and which are planets just by looking for the twinklers vs the non-twinklers? Experienced observers often can, but, at first, if you can recognize a planet in some other way, you might notice the steadiness of its light by contrasting it to a nearby star.
Bottom line: Stars appear as pinpoints of light, making them vulnerable to atmospheric disturbance, which is why they twinkle. Planets appear as tiny disks, producing a steadier beam of light that is less visibly affected by the atmosphere.
The more atmosphere you are peering through, the more stars (or sometimes planets) appear to twinkle. Read below why stars twinkle, but planets do not. Chart by AstroBob. Used with permission.
Stars twinkle, while planets (usually) shine steadily
Stars twinkle because they’re so far away from Earth that, even through large telescopes, they appear only as pinpoints. And it’s easy for Earth’s atmosphere to disturb the pinpoint light of a star. As a star’s light pierces our atmosphere, it’s refracted – causing it to change direction slightly – by the various temperature and density layers in Earth’s atmosphere. You might think of it as the light traveling a zig-zag path to our eyes, instead of the straight path the light would travel if Earth didn’t have an atmosphere.
Astronomers use the term “scintillation” to describe the twinkling of stars.
The twinkling of the stars is called scintillation. Stars are so far away, that they are actually just points of light pic.twitter.com/xcnIKKhYZE
Planets shine more steadily because they’re closer to Earth and so appear not as pinpoints, but as tiny disks in our sky. You can see planets as disks if you look through a telescope, while stars remain pinpoints. Earth’s atmosphere refracts the light from these little disks as it travels toward our eyes. But – while the light from one edge of a planet’s disk might “zig” one way – light from the opposite edge of the disk might be “zagging” in an opposite way. The zigs and zags of light from a planetary disk cancel each other out, and that’s why planets appear to shine steadily.
You might see planets twinkling if you spot them low in the sky. That’s because, in the direction of any horizon, you’re looking through more atmosphere than when you look overhead.
If you could see stars and planets from outer space, both would shine steadily. There would be no atmosphere to disturb the steady streaming of their light.
Can you figure out which objects are stars and which are planets just by looking for the twinklers vs the non-twinklers? Experienced observers often can, but, at first, if you can recognize a planet in some other way, you might notice the steadiness of its light by contrasting it to a nearby star.
Bottom line: Stars appear as pinpoints of light, making them vulnerable to atmospheric disturbance, which is why they twinkle. Planets appear as tiny disks, producing a steadier beam of light that is less visibly affected by the atmosphere.
Artist’s concept shows Voyager 1 against a starry background. The spacecraft, launched in 1977, is currently the most distant human-made object from Earth. It left our solar system when it exited the heliopause (the sphere of the sun’s influence) in 2012. NASA said last week that at 12:16:07 a.m. CST on November 18, 2026, Voyager 1 will reach a distance of 1 light-day from Earth. Image via Caltech/ NASA-JPL.
Voyager 1 to reach 1 light-day from Earth in November
Voyager 1 is the most distant human-made object from Earth. It launched into space on September 5, 1977, and visited Jupiter and Saturn before heading out of the solar system. It officially crossed out of our solar system, passing the heliopause – the sphere of the sun’s influence – back in 2012. And now, NASA said on June 17, 2026, that Voyager 1 will reach 1 light-day from Earth – or the distance it takes light to travel in 24 hours – at 12:16:07 a.m. CST on November 18, 2026. That’s just before midnight Eastern Time on November 17.
This historic milestone of 1 light-day is equal to about 16.1 billion miles (25.9 billion kilometers), or 173.14 astronomical units (AU). As of right now, mid-June 2026, the Voyager 1 spacecraft is about 15.82 billion miles (25.45 billion km) away from Earth. So the spacecraft is traveling at a scorching pace: 79.96 thousand miles per hour, or 128.7 thousand km per hour.
We’ve long known this milestone would come around the middle of November, 2026. But now, NASA has performed the complex calculations and announced an official time and date. Put it in the calendar!
Voyager 1 is now outside our solar system. On November 18, 2026, it will reach 1 light-day distant from Earth. Image via NASA/ JPL-Caltech.
What about Voyager 2?
And where is Voyager 2? You might know that Voyager 2 actually launched a few weeks before its sister craft. But while Voyager 1 only visited Jupiter and Saturn, Voyager 2 took a Grand Tour, visiting all the gas giant planets: Jupiter, Saturn, Uranus and Neptune. So it’s not as far from Earth as Voyager 1.
But it’s not too far behind, relatively speaking. Voyager 2 is about 2 billion miles closer to Earth than Voyager 1. It’s also moving a bit slower, at 65.33 thousand miles per hour (105.1 thousand km/h), so it can never catch up. Besides, Voyager 1 and 2 are not headed in the same direction anyway. Voyager 1 is headed “up” out of the solar plane, while Voyager 2 is headed “down.” Voyager 1 is moving toward the direction of the constellation Ophiuchus. And Voyager 2 is headed in the direction of the constellation Andromeda.
Are the Voyager spacecraft still functioning?
Both Voyager spacecraft are still in communication with Earth, even though that process takes approximately a day for one-way messages. But most of the instruments on the Voyagers are no longer working. Over the years, NASA has turned off one system after another in order to save power. Just a couple months ago, in April 2026, NASA turned off the Low-Energy Charged Particle (LECP) instrument to save energy. This instrument was detecting electrons, ions and cosmic rays in the interstellar medium. But NASA could still turn it on at some point in the future for new measurements.
Both Voyager spacecraft carry golden records that are etched with images and sounds to represent life on Earth. The golden records were a largely symbolic gesture meant to represent Earth in the wider universe and with the off-chance that an alien civilization would one day find them and learn something of their origins. As Carl Sagan said:
The spacecraft will be encountered and the record played only if there are advanced space-faring civilizations in interstellar space, but the launching of this ‘bottle’ into the cosmic ‘ocean’ says something very hopeful about life on this planet.
Bottom line: NASA said on June 17, 2026, that Voyager 1 will reach 1 light-day from Earth soon. It estimates the spacecraft will reach that mark on November 18, 2026.
Artist’s concept shows Voyager 1 against a starry background. The spacecraft, launched in 1977, is currently the most distant human-made object from Earth. It left our solar system when it exited the heliopause (the sphere of the sun’s influence) in 2012. NASA said last week that at 12:16:07 a.m. CST on November 18, 2026, Voyager 1 will reach a distance of 1 light-day from Earth. Image via Caltech/ NASA-JPL.
Voyager 1 to reach 1 light-day from Earth in November
Voyager 1 is the most distant human-made object from Earth. It launched into space on September 5, 1977, and visited Jupiter and Saturn before heading out of the solar system. It officially crossed out of our solar system, passing the heliopause – the sphere of the sun’s influence – back in 2012. And now, NASA said on June 17, 2026, that Voyager 1 will reach 1 light-day from Earth – or the distance it takes light to travel in 24 hours – at 12:16:07 a.m. CST on November 18, 2026. That’s just before midnight Eastern Time on November 17.
This historic milestone of 1 light-day is equal to about 16.1 billion miles (25.9 billion kilometers), or 173.14 astronomical units (AU). As of right now, mid-June 2026, the Voyager 1 spacecraft is about 15.82 billion miles (25.45 billion km) away from Earth. So the spacecraft is traveling at a scorching pace: 79.96 thousand miles per hour, or 128.7 thousand km per hour.
We’ve long known this milestone would come around the middle of November, 2026. But now, NASA has performed the complex calculations and announced an official time and date. Put it in the calendar!
Voyager 1 is now outside our solar system. On November 18, 2026, it will reach 1 light-day distant from Earth. Image via NASA/ JPL-Caltech.
What about Voyager 2?
And where is Voyager 2? You might know that Voyager 2 actually launched a few weeks before its sister craft. But while Voyager 1 only visited Jupiter and Saturn, Voyager 2 took a Grand Tour, visiting all the gas giant planets: Jupiter, Saturn, Uranus and Neptune. So it’s not as far from Earth as Voyager 1.
But it’s not too far behind, relatively speaking. Voyager 2 is about 2 billion miles closer to Earth than Voyager 1. It’s also moving a bit slower, at 65.33 thousand miles per hour (105.1 thousand km/h), so it can never catch up. Besides, Voyager 1 and 2 are not headed in the same direction anyway. Voyager 1 is headed “up” out of the solar plane, while Voyager 2 is headed “down.” Voyager 1 is moving toward the direction of the constellation Ophiuchus. And Voyager 2 is headed in the direction of the constellation Andromeda.
Are the Voyager spacecraft still functioning?
Both Voyager spacecraft are still in communication with Earth, even though that process takes approximately a day for one-way messages. But most of the instruments on the Voyagers are no longer working. Over the years, NASA has turned off one system after another in order to save power. Just a couple months ago, in April 2026, NASA turned off the Low-Energy Charged Particle (LECP) instrument to save energy. This instrument was detecting electrons, ions and cosmic rays in the interstellar medium. But NASA could still turn it on at some point in the future for new measurements.
Both Voyager spacecraft carry golden records that are etched with images and sounds to represent life on Earth. The golden records were a largely symbolic gesture meant to represent Earth in the wider universe and with the off-chance that an alien civilization would one day find them and learn something of their origins. As Carl Sagan said:
The spacecraft will be encountered and the record played only if there are advanced space-faring civilizations in interstellar space, but the launching of this ‘bottle’ into the cosmic ‘ocean’ says something very hopeful about life on this planet.
Bottom line: NASA said on June 17, 2026, that Voyager 1 will reach 1 light-day from Earth soon. It estimates the spacecraft will reach that mark on November 18, 2026.
