‘Continents’ on Venus similar to those of early Earth?

View larger. | Topographic radar map of Venus, the world next-inward from Earth. Ishtar Terra, the 2nd-largest Venus ‘continent,’ is the large reddish-colored plateau below the image’s center. A new study shows that the ‘continents’ on Venus likely formed through processes similar to those that produced Earth’s continents, despite the lack of plate tectonics on Venus. Image via the Magellan mission to Venus in the 1990s/ NASA/ JPL/ MIT/ USGS/ Wikimedia Commons (public domain).

• Venus has large plateaus called tesserae, and a new study suggests that they formed through processes similar to those that created early continents on Earth.
• But Venus doesn’t have plate tectonics, which played a key role in continent- and mountain-building on Earth. So scientists are surprised!
• The new study focused on Ishtar Terra, the 2nd-largest tessera on Venus. It’s about the same size as Australia.

Venus doesn’t have oceans. So it doesn’t have continents in the same sense that Earth does. But it does have vast plateaus called tesserae, which are akin to continents. Now a new study suggests the tesserae might have more in common with Earth’s continents than previously thought. Researchers said on August 2, 2024, that both Venus tesserae and early earthly continents on Earth could have formed through similar processes, even though Venus does not have plate tectonics, the process that, on our world, creates both continents and mountain ranges.

The research team, led by Fabio Capitanio from the Monash University School of Earth, Atmosphere and Environment, published its peer-reviewed findings in Nature Geoscience on August 2, 2024.

‘Continents’ on Venus challenge planetary knowledge

Since Venus lacks plate tectonics, the findings were a surprise for planetary scientists. Scientists didn’t expect Venus to have such complex geological processes, like the ones that gave rise to continents on Earth.

Capitanio said:

The study challenges our understanding of how planets evolve. We did not expect Venus, with its scorching 460 degrees Celsius (860 F) surface temperature and lack of plate tectonics, to possess such complex geological features.

The study focused on one tessera in particular, called Ishtar Terra, in the northern hemisphere. It is the second largest of the major plateaus on Venus, comparable in size to Australia. The researchers used computer simulations to see what the region was like billions of years ago.

Here’s a close radar view of the 2nd-largest “continent” on Venus, Ishtar Terra, imaged during the Magellan mission. In addition, the Maxwell Montes mountains are the white region in the lower right. They are the highest area on Venus and taller than Mount Everest on Earth. Image via NASA.

Similarities to early continents on Earth

The researchers said that Venus’ tesserae may have formed through geological process quite similar to the ones that produced the earliest continents on Earth. Those continents began as ancient cratons, the oldest parts of Earth’s continental crust. Cratons are the stable interior portions of continents, typically composed of ancient crystalline basement rock. In the cratons, the rock is older, denser and stronger. Overall, there are about 35 known cratons on Earth.

Scientists say they formed first, pushing upward through Earth’s molten interior. They then hardened, becoming the cores of what are now the modern continents.

Capitanio added:

This finding provides a fascinating new perspective on Venus and its potential links to early Earth. The features we found on Venus are strikingly similar to Earth’s early continents, suggesting that the dynamics of Venus’ past may have been more similar to Earth’s than previously thought.

View larger. | Here’s a color-coded visualization of Aphrodite Terra (in yellow) the largest continent-like tessera on Venus. Image via NASA/ Scientific Visualization Studio.

Divergent evolutionary paths

Scientists say that Venus was once much more Earth-like and possibly even had oceans. But something happened, and Venus and Earth then took very different evolutionary paths. The new results can provide more clues as to how these two worlds became so different. On Venus, the findings suggest that the divergence began after the cratons formed but before plate tectonics could start.

This can help scientists better understand how rocky planets like Venus and Earth form and evolve. It also provides clues about how a rocky planet could develop and maintain habitability, like Earth, or end up becoming uninhabitable on its surface, like Venus. So, by studying Venus’ history, scientists can learn more about Earth’s as well. As Capitanio noted:

By studying similar features on Venus, we hope to unlock the secrets of Earth’s early history.

Bottom line: A new study suggests that ‘continents’ on Venus, vast plateaus known as tesserae, may have formed in a very similar way to early continents on Earth.

Source: Ishtar Terra highlands on Venus raised by craton-like formation mechanisms

Via Monash University

Via ScienceAlert

Read more: Does phosphine on Venus mean … life?

Read more: Active Venus volcanoes revealed again in Magellan data

The post ‘Continents’ on Venus similar to those of early Earth? first appeared on EarthSky.

from EarthSky https://ift.tt/H19C37k

View larger. | Topographic radar map of Venus, the world next-inward from Earth. Ishtar Terra, the 2nd-largest Venus ‘continent,’ is the large reddish-colored plateau below the image’s center. A new study shows that the ‘continents’ on Venus likely formed through processes similar to those that produced Earth’s continents, despite the lack of plate tectonics on Venus. Image via the Magellan mission to Venus in the 1990s/ NASA/ JPL/ MIT/ USGS/ Wikimedia Commons (public domain).

• Venus has large plateaus called tesserae, and a new study suggests that they formed through processes similar to those that created early continents on Earth.
• But Venus doesn’t have plate tectonics, which played a key role in continent- and mountain-building on Earth. So scientists are surprised!
• The new study focused on Ishtar Terra, the 2nd-largest tessera on Venus. It’s about the same size as Australia.

Venus doesn’t have oceans. So it doesn’t have continents in the same sense that Earth does. But it does have vast plateaus called tesserae, which are akin to continents. Now a new study suggests the tesserae might have more in common with Earth’s continents than previously thought. Researchers said on August 2, 2024, that both Venus tesserae and early earthly continents on Earth could have formed through similar processes, even though Venus does not have plate tectonics, the process that, on our world, creates both continents and mountain ranges.

The research team, led by Fabio Capitanio from the Monash University School of Earth, Atmosphere and Environment, published its peer-reviewed findings in Nature Geoscience on August 2, 2024.

‘Continents’ on Venus challenge planetary knowledge

Since Venus lacks plate tectonics, the findings were a surprise for planetary scientists. Scientists didn’t expect Venus to have such complex geological processes, like the ones that gave rise to continents on Earth.

Capitanio said:

The study challenges our understanding of how planets evolve. We did not expect Venus, with its scorching 460 degrees Celsius (860 F) surface temperature and lack of plate tectonics, to possess such complex geological features.

The study focused on one tessera in particular, called Ishtar Terra, in the northern hemisphere. It is the second largest of the major plateaus on Venus, comparable in size to Australia. The researchers used computer simulations to see what the region was like billions of years ago.

Here’s a close radar view of the 2nd-largest “continent” on Venus, Ishtar Terra, imaged during the Magellan mission. In addition, the Maxwell Montes mountains are the white region in the lower right. They are the highest area on Venus and taller than Mount Everest on Earth. Image via NASA.

Similarities to early continents on Earth

The researchers said that Venus’ tesserae may have formed through geological process quite similar to the ones that produced the earliest continents on Earth. Those continents began as ancient cratons, the oldest parts of Earth’s continental crust. Cratons are the stable interior portions of continents, typically composed of ancient crystalline basement rock. In the cratons, the rock is older, denser and stronger. Overall, there are about 35 known cratons on Earth.

Scientists say they formed first, pushing upward through Earth’s molten interior. They then hardened, becoming the cores of what are now the modern continents.

Capitanio added:

This finding provides a fascinating new perspective on Venus and its potential links to early Earth. The features we found on Venus are strikingly similar to Earth’s early continents, suggesting that the dynamics of Venus’ past may have been more similar to Earth’s than previously thought.

View larger. | Here’s a color-coded visualization of Aphrodite Terra (in yellow) the largest continent-like tessera on Venus. Image via NASA/ Scientific Visualization Studio.

Divergent evolutionary paths

Scientists say that Venus was once much more Earth-like and possibly even had oceans. But something happened, and Venus and Earth then took very different evolutionary paths. The new results can provide more clues as to how these two worlds became so different. On Venus, the findings suggest that the divergence began after the cratons formed but before plate tectonics could start.

This can help scientists better understand how rocky planets like Venus and Earth form and evolve. It also provides clues about how a rocky planet could develop and maintain habitability, like Earth, or end up becoming uninhabitable on its surface, like Venus. So, by studying Venus’ history, scientists can learn more about Earth’s as well. As Capitanio noted:

By studying similar features on Venus, we hope to unlock the secrets of Earth’s early history.

Bottom line: A new study suggests that ‘continents’ on Venus, vast plateaus known as tesserae, may have formed in a very similar way to early continents on Earth.

Source: Ishtar Terra highlands on Venus raised by craton-like formation mechanisms

Via Monash University

Via ScienceAlert

Read more: Does phosphine on Venus mean … life?

Read more: Active Venus volcanoes revealed again in Magellan data

The post ‘Continents’ on Venus similar to those of early Earth? first appeared on EarthSky.

from EarthSky https://ift.tt/H19C37k

Hobbit human ancestors smaller than thought

This is a 700,000-year-old fossil humerus excavated at Mata Menge, on the island of Flores in Indonesia. It belonged to an ancestor of Homo floresiensis, the “hobbit” human. Image via Yousuke Kaifu / Griffith University.

• Homo floresiensis, an extinct human species, once lived on the island of Flores, in Indonesia. They were short in stature, just over 3 feet (1 meter) tall.
• These ancient humans were nicknamed “hobbits” because of their diminutive size.
• Fossils indicate Homo floresiensis’ small size likely occurred when their ancestors, possibly Homo erectus, became isolated on Flores and evolved over time.

Small statured ancient humans once lived on the Indonesian island of Flores. This now-extinct species, Homo floresiensis, is nicknamed “hobbit” because of their diminutive size. Now, scientists report finding a fossil arm bone – a section of the humerus – that reveals new details about the evolution of this enigmatic human species. It turns out that H. floresiensis’ ancestors were smaller than scientists had previously thought.

The researchers published their findings in the peer-reviewed journal Nature Communications on August 6, 2024.

Adam Brumm, of Griffith University, is a paper co-author. He said, in a statement:

This very rare specimen confirms our hypothesis that the ancestors of Homo floresiensis were extremely small in body size; however, it is now apparent from the tiny proportions of this limb bone that the early progenitors of the “hobbit” were even smaller than we had previously thought.

Homo floresiensis, a real human “hobbit”

A 10-minute video introduction to the “hobbit” humans, Homo floresiensis. Via PBS Eons.

In 2003, scientists uncovered the skeleton of an adult female hominin in a cave named Liang Bua, on the island of Flores, Indonesia. (Hominin is a term often used to refer to modern and extinct human species.) She was just 3 feet 5.7 inches tall (106 cm) and they date her remains as 60,000 years old.

Subsequently, they excavated more partial skeletons from individuals of a similar diminutive stature at this cave, along with stone tools.

They named this unique human species, found only in Flores, Homo floresiensis. Because of their small size, their discoverers nicknamed them “hobbits,” after the fictional little beings created by author J. R. R. Tolkien.

H. floresiensis, scientists think, became extinct about 50,000 years ago.

A facial reconstruction of the 60,000-year-old female Homo floresiensis found at Liang Bua Cave. Image via Cicero Moraes et al. / Wikimedia Commons.

There’s been much controversy over the origins of this enigmatic species. Some scientists think that H. floresiensis descended from an ancient human species called Homo erectus that arrived at Flores about one million years ago. Others wonder if these hominins evolved from another perhaps older human species.

It’s thought their small body size is due to a phenomenon known as insular dwarfism. That’s when large animals confined to a small environment, like an island, evolve to a reduced body size over many generations.

Older fossils discovered on Flores

Since the discoveries of H. floresiensis fossils at Liang Bua Cave, scientists have uncovered even older fossils on the island. They reported, in 2016, that hominin teeth and a jaw fragment, dated 700,000 years old, were unearthed at Mata Menge, a location just 47 miles (75 km) from the Liang Bua Cave.

The researchers were intrigued by these fossils because they are like the Liang Bua Cave individuals but they are a bit smaller in size. However, they needed bones below the head to get a better sense of the size of these hominins.

Then, in August 2024, scientists announced they had recovered and reconstructed a section of a humerus or upper arm bone. It’s dated as 700,000 years old. Moreover, a microscopic study of the humerus fossil bone structure determined that it came from an adult.

It was a significant find because scientists could now calculate the size of this individual. And that individual was just 3 feet 3.4 inches (100 cm) tall. That’s 2.4 inches (6 cm) shorter than the estimated height of the 60,000-year-old skeleton from the Liang Bua Cave.

In addition to the humerus fossil, they found two additional teeth. They were also smaller in size compared to the Liang Bua Cave specimens.

The bone on the far left is the humerus (700,000 years old) found at Mata Menge. For comparison, it’s shown here to scale next to a Homo floresiensis humerus from an almost complete skeleton (60,000 years old) found at Liang Bua Cave. Image via Yousuke Kaifu / Griffith University.

Trying to understand the evolution of the “hobbit” hominins

The Mata Menge fossils pre-date the Liang Bua skeleton by about 640,000 years. They are also anatomically similar. Therefore, scientists regard the Mata Menge individuals as ancestors of H. floresiensis from the Liang Bua Cave. However, the dentition of the Mata Menge fossils appears more primitive, according to the scientists.

They also note that the small arm bone indicates that H. floresiensis‘ extreme reduction in body size happened early in the history of this species. Brumm remarked in the statement:

The evolutionary history of the Flores hominins is still largely unknown.

However, the new fossils strongly suggest that the “hobbit” story did indeed begin when a group of the early Asian hominins known as Homo erectus somehow became isolated on this remote Indonesian island, perhaps one million years ago, and underwent a dramatic body size reduction over time.

Bottom line: Ancestors of Homo floresiensis, the “hobbit” humans, were smaller than scientists had previously thought.

Source: Early evolution of small body size in Homo floresiensis

Via Griffith University

Read more: ‘Hobbits’ among us? An anthropologist says maybe

The post Hobbit human ancestors smaller than thought first appeared on EarthSky.

from EarthSky https://ift.tt/gVedmEU

This is a 700,000-year-old fossil humerus excavated at Mata Menge, on the island of Flores in Indonesia. It belonged to an ancestor of Homo floresiensis, the “hobbit” human. Image via Yousuke Kaifu / Griffith University.

• Homo floresiensis, an extinct human species, once lived on the island of Flores, in Indonesia. They were short in stature, just over 3 feet (1 meter) tall.
• These ancient humans were nicknamed “hobbits” because of their diminutive size.
• Fossils indicate Homo floresiensis’ small size likely occurred when their ancestors, possibly Homo erectus, became isolated on Flores and evolved over time.

Small statured ancient humans once lived on the Indonesian island of Flores. This now-extinct species, Homo floresiensis, is nicknamed “hobbit” because of their diminutive size. Now, scientists report finding a fossil arm bone – a section of the humerus – that reveals new details about the evolution of this enigmatic human species. It turns out that H. floresiensis’ ancestors were smaller than scientists had previously thought.

The researchers published their findings in the peer-reviewed journal Nature Communications on August 6, 2024.

Adam Brumm, of Griffith University, is a paper co-author. He said, in a statement:

This very rare specimen confirms our hypothesis that the ancestors of Homo floresiensis were extremely small in body size; however, it is now apparent from the tiny proportions of this limb bone that the early progenitors of the “hobbit” were even smaller than we had previously thought.

Homo floresiensis, a real human “hobbit”

A 10-minute video introduction to the “hobbit” humans, Homo floresiensis. Via PBS Eons.

In 2003, scientists uncovered the skeleton of an adult female hominin in a cave named Liang Bua, on the island of Flores, Indonesia. (Hominin is a term often used to refer to modern and extinct human species.) She was just 3 feet 5.7 inches tall (106 cm) and they date her remains as 60,000 years old.

Subsequently, they excavated more partial skeletons from individuals of a similar diminutive stature at this cave, along with stone tools.

They named this unique human species, found only in Flores, Homo floresiensis. Because of their small size, their discoverers nicknamed them “hobbits,” after the fictional little beings created by author J. R. R. Tolkien.

H. floresiensis, scientists think, became extinct about 50,000 years ago.

A facial reconstruction of the 60,000-year-old female Homo floresiensis found at Liang Bua Cave. Image via Cicero Moraes et al. / Wikimedia Commons.

There’s been much controversy over the origins of this enigmatic species. Some scientists think that H. floresiensis descended from an ancient human species called Homo erectus that arrived at Flores about one million years ago. Others wonder if these hominins evolved from another perhaps older human species.

It’s thought their small body size is due to a phenomenon known as insular dwarfism. That’s when large animals confined to a small environment, like an island, evolve to a reduced body size over many generations.

Older fossils discovered on Flores

Since the discoveries of H. floresiensis fossils at Liang Bua Cave, scientists have uncovered even older fossils on the island. They reported, in 2016, that hominin teeth and a jaw fragment, dated 700,000 years old, were unearthed at Mata Menge, a location just 47 miles (75 km) from the Liang Bua Cave.

The researchers were intrigued by these fossils because they are like the Liang Bua Cave individuals but they are a bit smaller in size. However, they needed bones below the head to get a better sense of the size of these hominins.

Then, in August 2024, scientists announced they had recovered and reconstructed a section of a humerus or upper arm bone. It’s dated as 700,000 years old. Moreover, a microscopic study of the humerus fossil bone structure determined that it came from an adult.

It was a significant find because scientists could now calculate the size of this individual. And that individual was just 3 feet 3.4 inches (100 cm) tall. That’s 2.4 inches (6 cm) shorter than the estimated height of the 60,000-year-old skeleton from the Liang Bua Cave.

In addition to the humerus fossil, they found two additional teeth. They were also smaller in size compared to the Liang Bua Cave specimens.

The bone on the far left is the humerus (700,000 years old) found at Mata Menge. For comparison, it’s shown here to scale next to a Homo floresiensis humerus from an almost complete skeleton (60,000 years old) found at Liang Bua Cave. Image via Yousuke Kaifu / Griffith University.

Trying to understand the evolution of the “hobbit” hominins

The Mata Menge fossils pre-date the Liang Bua skeleton by about 640,000 years. They are also anatomically similar. Therefore, scientists regard the Mata Menge individuals as ancestors of H. floresiensis from the Liang Bua Cave. However, the dentition of the Mata Menge fossils appears more primitive, according to the scientists.

They also note that the small arm bone indicates that H. floresiensis‘ extreme reduction in body size happened early in the history of this species. Brumm remarked in the statement:

The evolutionary history of the Flores hominins is still largely unknown.

However, the new fossils strongly suggest that the “hobbit” story did indeed begin when a group of the early Asian hominins known as Homo erectus somehow became isolated on this remote Indonesian island, perhaps one million years ago, and underwent a dramatic body size reduction over time.

Bottom line: Ancestors of Homo floresiensis, the “hobbit” humans, were smaller than scientists had previously thought.

Source: Early evolution of small body size in Homo floresiensis

Via Griffith University

Read more: ‘Hobbits’ among us? An anthropologist says maybe

The post Hobbit human ancestors smaller than thought first appeared on EarthSky.

from EarthSky https://ift.tt/gVedmEU

See it! This week’s auroras and Perseids!

What an amazing week it’s been! The beloved Perseid meteor shower peaked on the mornings of August 12 and 13, 2024. At the same time, Earth was hit by a CME from the sun, causing geomagnetic storming up to G4 (severe) levels … providing magnificent displays of auroras! Thanks to all who contributed to EarthSky community photos!

Perseid meteors and aurora on August 11

View at EarthSky Community Photos. | Abhijit Patil from the wonderful Yosemite National Park in California, shared this image and wrote: “Ohh what to say about yesterday night!! All the planning was for the annual Perseids but the auroras stole the show. It was a mesmerizing night. Meteors flying all across the sky and the pillars of the northern lights dancing in the north. Such a dramatic night it was. The auroras lasted as long as the Perseids did until day break.” Thank you!

View at EarthSky Community Photos. | Steve Schaum from Catskills, New York, captured both the aurora and some meteors. Thank you!

View at EarthSky Community Photos. | Jeremy Likness from Agate Beach, Newport, Oregon, shared this image and wrote: “A Perseid meteor streaks across the curtain of aurora borealis rippling beneath the Big Dipper.” Thank you!

Meteors on August 10

View at EarthSky Community Photos. | David Cox from Deep River, Ontario, Canada, shared this wonderful composite image of Perseid meteors and the aurora. David wrote: “Series of images taken August 9 and 10, facing north-east. About 35 Perseid meteors were captured. Total capture time was about 3 hours.” Thank you!

View at EarthSky Community Photos. | Muhammed Aslam from Sindh, Pakistan, shared this photo of a meteor with Jupiter, Mars and the Pleiades star cluster. Thank you!

What an amazing week it’s been! The beloved Perseid meteor shower peaked just as auroras were gracing our skies. Wow! See images from the EarthSky community here.

The post See it! This week’s auroras and Perseids! first appeared on EarthSky.

from EarthSky https://ift.tt/IoixUgO

What an amazing week it’s been! The beloved Perseid meteor shower peaked on the mornings of August 12 and 13, 2024. At the same time, Earth was hit by a CME from the sun, causing geomagnetic storming up to G4 (severe) levels … providing magnificent displays of auroras! Thanks to all who contributed to EarthSky community photos!

Perseid meteors and aurora on August 11

View at EarthSky Community Photos. | Abhijit Patil from the wonderful Yosemite National Park in California, shared this image and wrote: “Ohh what to say about yesterday night!! All the planning was for the annual Perseids but the auroras stole the show. It was a mesmerizing night. Meteors flying all across the sky and the pillars of the northern lights dancing in the north. Such a dramatic night it was. The auroras lasted as long as the Perseids did until day break.” Thank you!

View at EarthSky Community Photos. | Steve Schaum from Catskills, New York, captured both the aurora and some meteors. Thank you!

View at EarthSky Community Photos. | Jeremy Likness from Agate Beach, Newport, Oregon, shared this image and wrote: “A Perseid meteor streaks across the curtain of aurora borealis rippling beneath the Big Dipper.” Thank you!

Meteors on August 10

View at EarthSky Community Photos. | David Cox from Deep River, Ontario, Canada, shared this wonderful composite image of Perseid meteors and the aurora. David wrote: “Series of images taken August 9 and 10, facing north-east. About 35 Perseid meteors were captured. Total capture time was about 3 hours.” Thank you!

View at EarthSky Community Photos. | Muhammed Aslam from Sindh, Pakistan, shared this photo of a meteor with Jupiter, Mars and the Pleiades star cluster. Thank you!

What an amazing week it’s been! The beloved Perseid meteor shower peaked just as auroras were gracing our skies. Wow! See images from the EarthSky community here.

The post See it! This week’s auroras and Perseids! first appeared on EarthSky.

from EarthSky https://ift.tt/IoixUgO

Do you love twilight? The 3 stages explained

Twilight is that magical time of day when a glow pervades the air, even though the sun is below the horizon. Earth’s atmosphere scatters the sun’s rays to create the colors of twilight. On worlds with no atmospheres, such as the moon, the sky falls instantly dark after the sun sets.

And, if you could see twilight from outer space, you’d find that it isn’t marked by a sharp boundary on Earth’s surface. Instead, the shadow line on Earth – sometimes called the terminator line – is spread over a fairly wide area on the surface and shows the gradual transition to darkness we all experience as night falls.

Astronomers – those experts on nighttime – recognize three stages of twilight. Keep reading to hear about the intricacies of civil, nautical and astronomical, below.

The 3 types of twilight. Image via TWCarlson/ Wikimedia Commons (CC BY-SA 4.0).

Stage 1: Civil twilight

Let’s consider the stages of twilight as occurring after sunset. Keep in mind that they would reverse their order at sunrise. Civil twilight begins the moment the sun slips below the horizon. The official definition of civil twilight is the time from when the sun disappears until the sun’s center is 6 degrees below the horizon. A measurement of 6 degrees of sky is a bit more than three fingers held at arm’s length.

During civil twilight, there’s enough light to see, but people turn on their lights to drive a car, and the streetlights are starting to come on. The brightest planets appear during civil twilight.

For mid latitudes, civil twilight lasts a bit longer in summer and winter and is a bit shorter in spring and fall. In spring and fall, the sun rises and sets more directly in the east and west. Therefore, it makes a straighter path downward (or upward), reaching the 6 degree mark in a shorter period of time. In summer and winter, the sun arcs across the sky, cutting across the horizon at an angle. This angle is more pronounced in summer, which is why civil twilight lasts the longest in summer. Civil twilight in mid latitudes can last, on average, 1/2 hour.

Compare this to tropical regions. At the equator, the length of civil twilight hardly varies. The sun around the equator makes a path across the sky that cuts cleanly down toward the horizon at sunset in a nearly perpendicular fashion. Therefore, the sun and its rays disappear faster, giving equatorial regions a shorter twilight than higher latitudes. Near the poles, twilight times last much longer.

Stage 2: Nautical twilight

In the evening, nautical twilight takes over where civil twilight ends. The definition of nautical twilight is the time period when the center of the sun is 6 degrees below the horizon to 12 degrees below the horizon. You can remember the name “nautical” because it ends when the distant line between sea and sky is no longer distinguishable. Also, more bright stars appear during this time, which was important in the early days of navigation. When nautical twilight began, sailors could use the stars as directional cues.

During nautical twilight, terrestrial objects are visible, but you need artificial lights to carry on outdoor activities.

For polar regions, the summer sun does not get more than 12 degrees below the horizon. Therefore, these regions have nautical twilight all night long, never reaching astronomical twilight or total darkness. For mid latitudes, nautical twilight can last from about 1/2 hour in spring, winter and fall, to about 45 minutes in summer.

Stage 3: Astronomical twilight

The darkest twilight stage is astronomical twilight. The definition of astronomical twilight is the period of time when the center of the sun is 12 degrees below the horizon to 18 degrees below the horizon. You probably don’t even notice any illumination left in the sky at this time.

For stargazers, this is the time when fainter stars, clusters and other sky objects appear and become good observing targets.

In mid latitudes, astronomical twilight can last about 1/2 hour from fall through spring but up to an hour in summer. Astronomical twilight begins about an hour to 1 1/2 hours after sunset for mid latitudes. So, as a rule of thumb, if you’d like to observe something in the night sky that isn’t particularly bright, you should wait about 90 minutes after sunset before you start observing.

Twilight photo gallery

Twilight on Earth, viewed from space. Astronauts aboard the International Space Station captured this photo – a single digital frame – in June 2001. On the right, you see Earth illuminated by the sun. On the left, it’s nighttime. Between, washed in subtle colors, is the realm of twilight. Image via ISS Expedition 2 Crew/ Gateway to Astronaut Photography of Earth/ NASA.

View at EarthSky Community Photos. | John Ashley of Amado, Arizona, caputured this image on July 6, 2024, and wrote: “A 1% crescent moon sets through twilight haze beyond the large telescopes (left horizon) at Kitt Peak National Observatory (43 miles from the camera) just after sunset on Saturday, July 7, 2024.” Thank you, John!

View at EarthSky Community Photos. | Pat Fogg in Claresholm, Alberta, Canada, captured this image of early twilight on June 23, 2023. Pat wrote: “Sunset looking west to the Porcupine Hills.” Thank you, Pat!

Bottom line: Twilight is that magical time between sunlight and darkness. Astronomers, the experts on nighttime, recognize three stages of twilight.

The post Do you love twilight? The 3 stages explained first appeared on EarthSky.

from EarthSky https://ift.tt/ZgtHl0d

Twilight is that magical time of day when a glow pervades the air, even though the sun is below the horizon. Earth’s atmosphere scatters the sun’s rays to create the colors of twilight. On worlds with no atmospheres, such as the moon, the sky falls instantly dark after the sun sets.

And, if you could see twilight from outer space, you’d find that it isn’t marked by a sharp boundary on Earth’s surface. Instead, the shadow line on Earth – sometimes called the terminator line – is spread over a fairly wide area on the surface and shows the gradual transition to darkness we all experience as night falls.

Astronomers – those experts on nighttime – recognize three stages of twilight. Keep reading to hear about the intricacies of civil, nautical and astronomical, below.

The 3 types of twilight. Image via TWCarlson/ Wikimedia Commons (CC BY-SA 4.0).

Stage 1: Civil twilight

Let’s consider the stages of twilight as occurring after sunset. Keep in mind that they would reverse their order at sunrise. Civil twilight begins the moment the sun slips below the horizon. The official definition of civil twilight is the time from when the sun disappears until the sun’s center is 6 degrees below the horizon. A measurement of 6 degrees of sky is a bit more than three fingers held at arm’s length.

During civil twilight, there’s enough light to see, but people turn on their lights to drive a car, and the streetlights are starting to come on. The brightest planets appear during civil twilight.

For mid latitudes, civil twilight lasts a bit longer in summer and winter and is a bit shorter in spring and fall. In spring and fall, the sun rises and sets more directly in the east and west. Therefore, it makes a straighter path downward (or upward), reaching the 6 degree mark in a shorter period of time. In summer and winter, the sun arcs across the sky, cutting across the horizon at an angle. This angle is more pronounced in summer, which is why civil twilight lasts the longest in summer. Civil twilight in mid latitudes can last, on average, 1/2 hour.

Compare this to tropical regions. At the equator, the length of civil twilight hardly varies. The sun around the equator makes a path across the sky that cuts cleanly down toward the horizon at sunset in a nearly perpendicular fashion. Therefore, the sun and its rays disappear faster, giving equatorial regions a shorter twilight than higher latitudes. Near the poles, twilight times last much longer.

Stage 2: Nautical twilight

In the evening, nautical twilight takes over where civil twilight ends. The definition of nautical twilight is the time period when the center of the sun is 6 degrees below the horizon to 12 degrees below the horizon. You can remember the name “nautical” because it ends when the distant line between sea and sky is no longer distinguishable. Also, more bright stars appear during this time, which was important in the early days of navigation. When nautical twilight began, sailors could use the stars as directional cues.

During nautical twilight, terrestrial objects are visible, but you need artificial lights to carry on outdoor activities.

For polar regions, the summer sun does not get more than 12 degrees below the horizon. Therefore, these regions have nautical twilight all night long, never reaching astronomical twilight or total darkness. For mid latitudes, nautical twilight can last from about 1/2 hour in spring, winter and fall, to about 45 minutes in summer.

Stage 3: Astronomical twilight

The darkest twilight stage is astronomical twilight. The definition of astronomical twilight is the period of time when the center of the sun is 12 degrees below the horizon to 18 degrees below the horizon. You probably don’t even notice any illumination left in the sky at this time.

For stargazers, this is the time when fainter stars, clusters and other sky objects appear and become good observing targets.

In mid latitudes, astronomical twilight can last about 1/2 hour from fall through spring but up to an hour in summer. Astronomical twilight begins about an hour to 1 1/2 hours after sunset for mid latitudes. So, as a rule of thumb, if you’d like to observe something in the night sky that isn’t particularly bright, you should wait about 90 minutes after sunset before you start observing.

Twilight photo gallery

Twilight on Earth, viewed from space. Astronauts aboard the International Space Station captured this photo – a single digital frame – in June 2001. On the right, you see Earth illuminated by the sun. On the left, it’s nighttime. Between, washed in subtle colors, is the realm of twilight. Image via ISS Expedition 2 Crew/ Gateway to Astronaut Photography of Earth/ NASA.

View at EarthSky Community Photos. | John Ashley of Amado, Arizona, caputured this image on July 6, 2024, and wrote: “A 1% crescent moon sets through twilight haze beyond the large telescopes (left horizon) at Kitt Peak National Observatory (43 miles from the camera) just after sunset on Saturday, July 7, 2024.” Thank you, John!

View at EarthSky Community Photos. | Pat Fogg in Claresholm, Alberta, Canada, captured this image of early twilight on June 23, 2023. Pat wrote: “Sunset looking west to the Porcupine Hills.” Thank you, Pat!

Bottom line: Twilight is that magical time between sunlight and darkness. Astronomers, the experts on nighttime, recognize three stages of twilight.

The post Do you love twilight? The 3 stages explained first appeared on EarthSky.

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Flamingos are beautiful and peculiar: Lifeform of the week

Flamingos … What beautiful and peculiar creatures! Have you ever wondered why they are pink? This is not a very common color in nature. They also produce milk and sleep standing on just one leg. What a balance! Keep reading to answer this question and learn more interesting facts.

Why are flamingos pink?

There are six species of flamingos, and although each one has its peculiarities, all of them have some amount of pink color. But the color of their plumage is not a product of genetic constitution. It depends on their diet.

They need water to survive. Their natural habitat is areas of abundant water and mud, which is why they are found in wetlands, marshes, lagoons, lakes and swampy areas.

Depending on the area they live in, there are different resources at their disposal. They feed on almost anything, such as small crustaceans, mollusks, annelids, larvae, insects, fish, bacteria, microorganisms and algae.

However, their diet is high in carotenoids, a pigment that plants and algae produce. Flamingos metabolize them and that gives rise to their color. In fact, flamingo chicks are white or gray. Only when they begin to consume food rich in carotenoids do they start to acquire a pink color.

Carotenoids also give the characteristic color to many vegetables, crutaceans and shrimp. Artemia salina is a small crustacean that flamingos eat in large amounts, along with algae and shrimp, and that produces the most color. The more pink or red food a flamingo eats for a long period of time, the more pink or reddish they become. Thus, they are what they eat.

Other animals, including humans, could change their skin or plumage color, but they would need to consume plenty of carotenoids as a constant routine. Can you imagine eating carrots for days to get an orange color?

Flamingos get their color from their diet high in carotenoids. Image via Edrick Krozendijk/ Pexels.

They have a very different beak from other birds

Flamingos are filter-feeding birds using the best tool possible for feeding: their beak. They use their long legs to stir up the bottom of shallow waters. Then, they take in some water with their beak and use their tongue to retain the food and expel the water and mud.

Additionally, flamingos eat with their head upside down. That’s because of the curved shape of their beak. Flamingos bend down, submerge their head and take in water with their beak and filter it. Even though they are facing down, they can freely move their jaws, which helps with feeding.

Flamingos eat with their head upside down. Their beak functions as a filter. Image via Son Ngoc/ Pexels.

They are marvelous parents

Flamingos are very sociable. They live in large groups and mate with members of their own flock. Mating starts with a courtship that the largest males usually initiate. They begin to move their head and wings and strut. As with peacocks, male flamingos proudly display their beautiful plumage to attract the attention of females.

The selection of partners is very important, since flamingos are monogamous, that is, male and female will spend their entire lives together. All flamingos are caring fathers and mothers who are very involved in taking care of their offspring.

Flamingos build their nests with their legs, forming a cone-shaped mound with mud, wider at the base and narrower at the top. It measures between 12 and 15 inches (30 and 40 cm) in height.

They then make a hole in the center, where the female lays her eggs, usually just one, sometimes two. Incubation lasts about 30 days. At birth, the chicks have white or gray feathers. Flamingos can live 20 to 30 years in the wild or about 50 years in captivity.

Flamingos mate for life. They are amazing parents. Both of them participate in the construction of the nests, incubation and subsequent care of the chicks. Image via Kalidasan Gopi/ Pexels.

Flamingos produce milk

Both parents participate in building the nests, incubation and subsequent care of the chicks. And did you know that flamingos produce milk? Actually, it is not milk as we know it, but a substance that both females and males produce to feed the chicks.

It is called crop milk and, since they do not have nipples or mammary glands, flamingos produce it from a specialized part of their digestive tract, and give it to the chicks through their beak.

Their milk is rich in fat, protein and other nutrients. In addition, it has a pink color due to the high carotenoids content from the parents’ food. This allows the little flamingos to start getting the pink tone in their feathers. Watch a video of adult flamingos eating and feeding their chicks.

Both female and male flamingos can produce a sort of milk to feed their chicks. This milk is rich in fat, protein and other nutrients. Image via Mohamed Raseem/ Pexels.

Flamingos have a curious anatomy

Flamingos have knees on each leg, but they are only visible if you look at them from a close distance, because they are half-hidden under feathers. And the joints seen in the middle of the legs are their ankles and heels.

They all have three toes facing forward and joined by a membrane that helps them swim and keeps them from sinking in the mud. Their curved neck has 19 cervical vertebrae.

Their beak is strong and each jaw has two rows of lamellae (thin plates) that filter food; they do not chew their food. Although their habitat is usually salty, they drink fresh water.

Amazingly, in flight they can reach speeds up to 37 miles per hour (60 kph).

Flamingos have knees, ankles and heels. Plus they have 3 toes on each leg joined by a membrane. Also their long neck has 19 cervical vertebrae. Image via Cesar Aguilar/ Pexels.

They stand on one leg while resting

Have you noticed that flamingos stand on one leg? Scientists are considering some hypotheses.

One theory that’s common in other birds, is that it reduces heat loss (this is called thermoregulation). By exposing only one leg while the other is warm under the plumage, they lose less heat. Also, they place their head close to the body or under the feathers while sleeping to keep the warmth.

Another theory is that this prevents both legs from being rigid, allowing them to escape from a predator.

Others say they perch on one leg to save energy, since this position does not require active muscular effort.

Flamingos may rest on just one leg to avoid losing heat. Image via Thomas Griggs/ Unsplash.

Greater and lesser flamingos

The six types of flamingos are:

The greater flamingo. It’s the largest species of all and it’s 4 to 5 feet (120 to 150 cm) tall and weighs approximately 9 pounds (4 kg). It’s located in Asia, Africa and Europe.

A greater flamingo. Image via Chris Down/ Wikipedia (CC BY 4.0).

Then the lesser flamingo is the smallest. It’s 31 inches (80 cm) tall and weighs 5 pounds (2.5 kg). It’s native to Africa, although it is also found in some areas of Asia such as India, Pakistan and other regions such as Spain.

A lesser flamingo. Image via Lip Kee/ Wikipedia (CC BY-SA 2.0).

The American and Chilean flamingos

The American flamingo. It’s distributed from the south of the United States to the Galapagos Islands, and in Ecuador, Colombia, Brazil, Venezuela and all the Caribbean islands.

An American flamingo flying. Image via Brandon Trentler/ Wikipedia (CC BY 2.0).

The Chilean flamingo. It’s native to Argentina, Bolivia, Chile, Paraguay and Peru. It’s also found in Brazil, Ecuador and Uruguay.

A Chilean flamingo and its egg. Image via Tragopan/ Wikipedia (CC BY-SA 3.0).

The Andean and James’s flamingos

The Andean flamingo. It’s native to Argentina, Bolivia, Chile and Peru, and sometimes Brazil.

An Andean flamingo. Image via Mauricio Sandoval Reyes/ Wikipedia (CC BY-SA 3.0).

The James’s flamingo. It’s native to Argentina, Chile, Bolivia and Peru.

James’s flamingos. Image via Christian Mehlführer/ Wikipedia (CC BY-SA 3.0).

Unfortunately, flamingos have a number of predators such as lions, leopards, cheetahs, jaguars, foxes, crocodiles, badgers … Even so, you can find the largest community of flamingos in Africa. It has more than a million members.

Bottom line: Flamingos are exotic birds that eat upside down, can produce milk, are amazing parents to their chicks and sleep on one leg. How cool are they?

Hummingbirds, tiny and colorful: Lifeform of the week

Vultures are the best clean-up crew: Lifeform of the week

The post Flamingos are beautiful and peculiar: Lifeform of the week first appeared on EarthSky.

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Flamingos … What beautiful and peculiar creatures! Have you ever wondered why they are pink? This is not a very common color in nature. They also produce milk and sleep standing on just one leg. What a balance! Keep reading to answer this question and learn more interesting facts.

Why are flamingos pink?

There are six species of flamingos, and although each one has its peculiarities, all of them have some amount of pink color. But the color of their plumage is not a product of genetic constitution. It depends on their diet.

They need water to survive. Their natural habitat is areas of abundant water and mud, which is why they are found in wetlands, marshes, lagoons, lakes and swampy areas.

Depending on the area they live in, there are different resources at their disposal. They feed on almost anything, such as small crustaceans, mollusks, annelids, larvae, insects, fish, bacteria, microorganisms and algae.

However, their diet is high in carotenoids, a pigment that plants and algae produce. Flamingos metabolize them and that gives rise to their color. In fact, flamingo chicks are white or gray. Only when they begin to consume food rich in carotenoids do they start to acquire a pink color.

Carotenoids also give the characteristic color to many vegetables, crutaceans and shrimp. Artemia salina is a small crustacean that flamingos eat in large amounts, along with algae and shrimp, and that produces the most color. The more pink or red food a flamingo eats for a long period of time, the more pink or reddish they become. Thus, they are what they eat.

Other animals, including humans, could change their skin or plumage color, but they would need to consume plenty of carotenoids as a constant routine. Can you imagine eating carrots for days to get an orange color?

Flamingos get their color from their diet high in carotenoids. Image via Edrick Krozendijk/ Pexels.

They have a very different beak from other birds

Flamingos are filter-feeding birds using the best tool possible for feeding: their beak. They use their long legs to stir up the bottom of shallow waters. Then, they take in some water with their beak and use their tongue to retain the food and expel the water and mud.

Additionally, flamingos eat with their head upside down. That’s because of the curved shape of their beak. Flamingos bend down, submerge their head and take in water with their beak and filter it. Even though they are facing down, they can freely move their jaws, which helps with feeding.

Flamingos eat with their head upside down. Their beak functions as a filter. Image via Son Ngoc/ Pexels.

They are marvelous parents

Flamingos are very sociable. They live in large groups and mate with members of their own flock. Mating starts with a courtship that the largest males usually initiate. They begin to move their head and wings and strut. As with peacocks, male flamingos proudly display their beautiful plumage to attract the attention of females.

The selection of partners is very important, since flamingos are monogamous, that is, male and female will spend their entire lives together. All flamingos are caring fathers and mothers who are very involved in taking care of their offspring.

Flamingos build their nests with their legs, forming a cone-shaped mound with mud, wider at the base and narrower at the top. It measures between 12 and 15 inches (30 and 40 cm) in height.

They then make a hole in the center, where the female lays her eggs, usually just one, sometimes two. Incubation lasts about 30 days. At birth, the chicks have white or gray feathers. Flamingos can live 20 to 30 years in the wild or about 50 years in captivity.

Flamingos mate for life. They are amazing parents. Both of them participate in the construction of the nests, incubation and subsequent care of the chicks. Image via Kalidasan Gopi/ Pexels.

Flamingos produce milk

Both parents participate in building the nests, incubation and subsequent care of the chicks. And did you know that flamingos produce milk? Actually, it is not milk as we know it, but a substance that both females and males produce to feed the chicks.

It is called crop milk and, since they do not have nipples or mammary glands, flamingos produce it from a specialized part of their digestive tract, and give it to the chicks through their beak.

Their milk is rich in fat, protein and other nutrients. In addition, it has a pink color due to the high carotenoids content from the parents’ food. This allows the little flamingos to start getting the pink tone in their feathers. Watch a video of adult flamingos eating and feeding their chicks.

Both female and male flamingos can produce a sort of milk to feed their chicks. This milk is rich in fat, protein and other nutrients. Image via Mohamed Raseem/ Pexels.

Flamingos have a curious anatomy

Flamingos have knees on each leg, but they are only visible if you look at them from a close distance, because they are half-hidden under feathers. And the joints seen in the middle of the legs are their ankles and heels.

They all have three toes facing forward and joined by a membrane that helps them swim and keeps them from sinking in the mud. Their curved neck has 19 cervical vertebrae.

Their beak is strong and each jaw has two rows of lamellae (thin plates) that filter food; they do not chew their food. Although their habitat is usually salty, they drink fresh water.

Amazingly, in flight they can reach speeds up to 37 miles per hour (60 kph).

Flamingos have knees, ankles and heels. Plus they have 3 toes on each leg joined by a membrane. Also their long neck has 19 cervical vertebrae. Image via Cesar Aguilar/ Pexels.

They stand on one leg while resting

Have you noticed that flamingos stand on one leg? Scientists are considering some hypotheses.

One theory that’s common in other birds, is that it reduces heat loss (this is called thermoregulation). By exposing only one leg while the other is warm under the plumage, they lose less heat. Also, they place their head close to the body or under the feathers while sleeping to keep the warmth.

Another theory is that this prevents both legs from being rigid, allowing them to escape from a predator.

Others say they perch on one leg to save energy, since this position does not require active muscular effort.

Flamingos may rest on just one leg to avoid losing heat. Image via Thomas Griggs/ Unsplash.

Greater and lesser flamingos

The six types of flamingos are:

The greater flamingo. It’s the largest species of all and it’s 4 to 5 feet (120 to 150 cm) tall and weighs approximately 9 pounds (4 kg). It’s located in Asia, Africa and Europe.

A greater flamingo. Image via Chris Down/ Wikipedia (CC BY 4.0).

Then the lesser flamingo is the smallest. It’s 31 inches (80 cm) tall and weighs 5 pounds (2.5 kg). It’s native to Africa, although it is also found in some areas of Asia such as India, Pakistan and other regions such as Spain.

A lesser flamingo. Image via Lip Kee/ Wikipedia (CC BY-SA 2.0).

The American and Chilean flamingos

The American flamingo. It’s distributed from the south of the United States to the Galapagos Islands, and in Ecuador, Colombia, Brazil, Venezuela and all the Caribbean islands.

An American flamingo flying. Image via Brandon Trentler/ Wikipedia (CC BY 2.0).

The Chilean flamingo. It’s native to Argentina, Bolivia, Chile, Paraguay and Peru. It’s also found in Brazil, Ecuador and Uruguay.

A Chilean flamingo and its egg. Image via Tragopan/ Wikipedia (CC BY-SA 3.0).

The Andean and James’s flamingos

The Andean flamingo. It’s native to Argentina, Bolivia, Chile and Peru, and sometimes Brazil.

An Andean flamingo. Image via Mauricio Sandoval Reyes/ Wikipedia (CC BY-SA 3.0).

The James’s flamingo. It’s native to Argentina, Chile, Bolivia and Peru.

James’s flamingos. Image via Christian Mehlführer/ Wikipedia (CC BY-SA 3.0).

Unfortunately, flamingos have a number of predators such as lions, leopards, cheetahs, jaguars, foxes, crocodiles, badgers … Even so, you can find the largest community of flamingos in Africa. It has more than a million members.

Bottom line: Flamingos are exotic birds that eat upside down, can produce milk, are amazing parents to their chicks and sleep on one leg. How cool are they?

Hummingbirds, tiny and colorful: Lifeform of the week

Vultures are the best clean-up crew: Lifeform of the week

The post Flamingos are beautiful and peculiar: Lifeform of the week first appeared on EarthSky.

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LIVE: What’s Phil thinking of NOW? GAIA

What’s Phil thinking? He’s thinking about the wealth of knowledge about our home galaxy, the Milky Way, provided by ESA’s GAIA space observatory.

Phil Plait – the Bad Astronomer, science blogger, dork and Crash Course Astronomy guy – will join EarthSky’s Deborah Byrd LIVE beginning at 12:15 p.m. central (17:15 UTC) on Monday, August 12. He’ll be talking about the mighty GAIA space observatory.

Launched in 2013 by the European Space Agency, GAIA’s mission is to scan the sky repeatedly. It has observed each of its targeted BILLION objects in our Milky Way galaxy, over and over again. It has gathered phenomenal data on the motions – and precise distances – of stars and other objects in our Milky Way. So, for example, we knew that our sun and all the stars in the Milky Way are moving continuously in great orderly masses around the center of our galaxy. But, now, thanks to GAIA, we have precise data on exactly HOW they are moving. For astronomers, the insights made possible by this data are nothing short of revolutionary. Phil said:

I want to talk about distances to stars, their motions, and how that’s been used to find stellar streams (cannibalized galaxies!), black holes in binary systems, black holes in globular clusters, and one of my favorite topics, whether the star Albireo is a binary or not).

There’s other stuff too, like showing that M73 is not an actual cluster, and how GAIA has detected planets. GAIA can even tell us which stars have come close to the sun over time.

Tons of stuff to say about GAIA! :)

Phil has written three books: Bad Astronomy (2002), Death from the Skies!, and Under Alien Skies: A Sightseer’s Guide to the Universe (2023).

Join us! And hear Phil tell us about some of GAIA’s most amazing discoveries.

Phil Plait, aka the Bad Astronomer.

Bottom line: What’s Phil thinking? Join Phil Plait, aka The Bad Astronomer, beginning at 12:15 p.m. central (17:15 UTC) on Monday, August 12 … to hear Phil talk about the mighty GAIA space observatory.

The post LIVE: What’s Phil thinking of NOW? GAIA first appeared on EarthSky.

from EarthSky https://ift.tt/3XKeFiu

What’s Phil thinking? He’s thinking about the wealth of knowledge about our home galaxy, the Milky Way, provided by ESA’s GAIA space observatory.

Phil Plait – the Bad Astronomer, science blogger, dork and Crash Course Astronomy guy – will join EarthSky’s Deborah Byrd LIVE beginning at 12:15 p.m. central (17:15 UTC) on Monday, August 12. He’ll be talking about the mighty GAIA space observatory.

Launched in 2013 by the European Space Agency, GAIA’s mission is to scan the sky repeatedly. It has observed each of its targeted BILLION objects in our Milky Way galaxy, over and over again. It has gathered phenomenal data on the motions – and precise distances – of stars and other objects in our Milky Way. So, for example, we knew that our sun and all the stars in the Milky Way are moving continuously in great orderly masses around the center of our galaxy. But, now, thanks to GAIA, we have precise data on exactly HOW they are moving. For astronomers, the insights made possible by this data are nothing short of revolutionary. Phil said:

I want to talk about distances to stars, their motions, and how that’s been used to find stellar streams (cannibalized galaxies!), black holes in binary systems, black holes in globular clusters, and one of my favorite topics, whether the star Albireo is a binary or not).

There’s other stuff too, like showing that M73 is not an actual cluster, and how GAIA has detected planets. GAIA can even tell us which stars have come close to the sun over time.

Tons of stuff to say about GAIA! :)

Phil has written three books: Bad Astronomy (2002), Death from the Skies!, and Under Alien Skies: A Sightseer’s Guide to the Universe (2023).

Join us! And hear Phil tell us about some of GAIA’s most amazing discoveries.

Phil Plait, aka the Bad Astronomer.

Bottom line: What’s Phil thinking? Join Phil Plait, aka The Bad Astronomer, beginning at 12:15 p.m. central (17:15 UTC) on Monday, August 12 … to hear Phil talk about the mighty GAIA space observatory.

The post LIVE: What’s Phil thinking of NOW? GAIA first appeared on EarthSky.

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Don’t miss! Jupiter and Mars conjunction this week

Jupiter and Mars are found in the east before sunrise throughout August 2024. Jupiter is brighter than Mars. At the beginning of August, Mars lies higher in the sky than Jupiter. By the morning of August 14, they’re in conjunction, shining next to each other as dawn breaks. At this point, Jupiter passes Mars. It continues ascending high in the eastern, predawn sky so that, by the end of August, Mars will shine from below Jupiter. Chart via EarthSky.

Jupiter and Mars to pair up August 14

Bright Jupiter and red Mars have been near each other in the east before sunup all month. And – if you watch in the coming week – you’ll get to see Jupiter sideswipe Mars in a conjunction. They’ll be closest on August 14. Afterwards, Mars will be creeping higher in the predawn sky, brightening slowly. Jupiter will ascend faster, pulling rapidly away from Mars, steadily moving toward the evening sky and its early December, 2024, opposition.

Jupiter and Mars are in front of the constellation boundary into Taurus the Bull. There are many splendid things to see in Taurus. This conjunction will be fun!

The two are not far from the misty Pleiades star cluster.

And they’re near bright Aldebaran – Eye of the Bull in Taurus – and a rival in brightness and color to Mars.

Read: Why is Mars sometimes bright and sometimes faint?

Here’s a 1-minute video preview of Jupiter and Mars conjunction around August 14.

The big event: Jupiter and Mars conjunction

The closest pairing of this planetary duo will come on the morning of August 14. That’s when bright gas giant Jupiter will get a visit from rocky red Mars on our sky’s dome. Then, the little planet will appear less than the width of a full moon from Jupiter. They’ll look close on our sky’s dome. In reality, the two will remain more than 300 million miles (500 million km) apart, even though they are next-door neighbors in our solar system.

Using just the unaided eye, the bright white light of Jupiter will contrast nicely with the dimmer and distinctly redder shine of Mars. In binoculars, Jupiter’s moons will enhance your enjoyment of the view. And this conjunction will be a great event for telescope owners and astrophotographers. You’ll be able to capture both planets in one view and thoroughly examine these remarkably different worlds. If you catch a great pic, please submit it to EarthSky’s community page!

You don’t need binoculars to see red Mars near bright Jupiter from August 10 through August 18. But binoculars will enhance the view. Watch for Jupiter and Mars at their closest in the early morning hours of August 14. Chart by John Jardine Goss/ EarthSky.

Charts from UK astronomer Guy Ottewell

The following charts are from beloved U.K. astronomer Guy Ottewell. He’s perhaps the world’s greatest living night sky illustrator! You’ll find more charts like these for 2024 in his Astronomical Calendar.

On the morning of August 9, 2024, Jupiter and Mars will be nearing their closest approach to each other. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

On August 12, 2024, look for the Jupiter and Mars conjunction in the morning sky. The planets will be in the constellation Taurus. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

Heliocentric solar system view of the planets in August 2024

Here’s more from Guy Ottewell … a heliocentric view of the solar system from above for August when Jupiter and Mars will appear close together in the morning sky. Guy Ottewell explains his heliocentric charts here .

Heliocentric view of solar system, August 2024. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

Bottom line: The Jupiter and Mars conjunction in the morning sky is this week! They’ll be closest on August 14. Look east!

The post Don’t miss! Jupiter and Mars conjunction this week first appeared on EarthSky.

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Jupiter and Mars are found in the east before sunrise throughout August 2024. Jupiter is brighter than Mars. At the beginning of August, Mars lies higher in the sky than Jupiter. By the morning of August 14, they’re in conjunction, shining next to each other as dawn breaks. At this point, Jupiter passes Mars. It continues ascending high in the eastern, predawn sky so that, by the end of August, Mars will shine from below Jupiter. Chart via EarthSky.

Jupiter and Mars to pair up August 14

Bright Jupiter and red Mars have been near each other in the east before sunup all month. And – if you watch in the coming week – you’ll get to see Jupiter sideswipe Mars in a conjunction. They’ll be closest on August 14. Afterwards, Mars will be creeping higher in the predawn sky, brightening slowly. Jupiter will ascend faster, pulling rapidly away from Mars, steadily moving toward the evening sky and its early December, 2024, opposition.

Jupiter and Mars are in front of the constellation boundary into Taurus the Bull. There are many splendid things to see in Taurus. This conjunction will be fun!

The two are not far from the misty Pleiades star cluster.

And they’re near bright Aldebaran – Eye of the Bull in Taurus – and a rival in brightness and color to Mars.

Read: Why is Mars sometimes bright and sometimes faint?

Here’s a 1-minute video preview of Jupiter and Mars conjunction around August 14.

The big event: Jupiter and Mars conjunction

The closest pairing of this planetary duo will come on the morning of August 14. That’s when bright gas giant Jupiter will get a visit from rocky red Mars on our sky’s dome. Then, the little planet will appear less than the width of a full moon from Jupiter. They’ll look close on our sky’s dome. In reality, the two will remain more than 300 million miles (500 million km) apart, even though they are next-door neighbors in our solar system.

Using just the unaided eye, the bright white light of Jupiter will contrast nicely with the dimmer and distinctly redder shine of Mars. In binoculars, Jupiter’s moons will enhance your enjoyment of the view. And this conjunction will be a great event for telescope owners and astrophotographers. You’ll be able to capture both planets in one view and thoroughly examine these remarkably different worlds. If you catch a great pic, please submit it to EarthSky’s community page!

You don’t need binoculars to see red Mars near bright Jupiter from August 10 through August 18. But binoculars will enhance the view. Watch for Jupiter and Mars at their closest in the early morning hours of August 14. Chart by John Jardine Goss/ EarthSky.

Charts from UK astronomer Guy Ottewell

The following charts are from beloved U.K. astronomer Guy Ottewell. He’s perhaps the world’s greatest living night sky illustrator! You’ll find more charts like these for 2024 in his Astronomical Calendar.

On the morning of August 9, 2024, Jupiter and Mars will be nearing their closest approach to each other. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

On August 12, 2024, look for the Jupiter and Mars conjunction in the morning sky. The planets will be in the constellation Taurus. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

Heliocentric solar system view of the planets in August 2024

Here’s more from Guy Ottewell … a heliocentric view of the solar system from above for August when Jupiter and Mars will appear close together in the morning sky. Guy Ottewell explains his heliocentric charts here .

Heliocentric view of solar system, August 2024. Chart via Guy Ottewell’s 2024 Astronomical Calendar. Used with permission.

Bottom line: The Jupiter and Mars conjunction in the morning sky is this week! They’ll be closest on August 14. Look east!

The post Don’t miss! Jupiter and Mars conjunction this week first appeared on EarthSky.

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