aads

A filament of the cosmic web! Clearest image yet

Cosmic web: A starfield with purple blobs thicker at 2 ends with thinner material stretching between.
This new image from the European Southern Observatory’s Very Large Telescope in Chile provides our clearest view yet of a filament in the cosmic web. The cosmic web is a network of filaments and voids that make up the large-scale structure of the universe. It’s composed primarily of invisible dark matter. But, in this image, the purple glow traces a gas bridge between distant galaxies. This gas clumped together thanks to dark matter’s influence. Image via ESO/ D. Tornotti et al./ Hubble: M. Revalski, P. Francis et al.

A glimpse of the cosmic web

Astronomers speak of the cosmic web as the most fundamental, large-scale structure of our universe. They picture it as a network of filaments and voids – spanning untold billions of light-years – whose skeleton is formed primarily by invisible dark matter. And, although we can’t see it, astronomers estimate that some 85% of all matter in our universe is dark matter. So it seems logical, but how can we know for sure that the cosmic web is even there?

The answer is that we see dark matter’s influence on other components of our universe. In the case of this image, we see a bridge of gas stretched between two distant galaxies in the early universe. The European Southern Observatory (ESO) shared this image on January 29, 2025. They said it represents the “clearest image yet” of a filament of the cosmic web.

The researchers published their peer-reviewed study of this image on January 29, in the journal Nature Astronomy.

Bridging 2 galaxies

The starfield in the background of the image is from the Hubble Space Telescope. But look more closely. You might be able to see a fuzziness to many of these “stars,” which – except for a few bright spiky objects – aren’t stars at all, but instead distant galaxies. The purple color is an overlay of the location of gas that has clumped together, thanks to the influence of dark matter.

The two larger concentrations center on galaxies, while the thin filament between them represents a bridge of material.

This filament of the cosmic web is huge! It’s some 3 million light-years long. The researchers found this faint bridge of glowing gas by making 150 hours of observations with the MUSE instrument on ESO’s Very Large Telescope in Chile.

Lead author Davide Tornotti of the University of Milano-Bicocca in Italy led the team that conducted the high-definition imaging of the filament. The filament was located at a redshift of what astronomers call z = 3, which is equivalent to a distance from Earth of more than 11 billion light-years.

A prediction of cold dark matter theory

The discovery is a boost to the prevailing model used by scientists to understand how our universe works and fits together. That model is called the Lambda CDM model, for Lambda cold dark matter. It’s a mathematical model, integrated into the Big Bang theory. The model suggests that dark matter consists of particles moving much more slowly than the speed of light. Many (but not all) astronomers feel that this still-hypothetical type of dark matter is the best fit with what we see in the universe so far. It explains how the smooth early cosmos turned into the clumps and then structures – such as galaxies – that we see today.

One long-standing prediction of the Lambda CDM model involves the idea of filaments between the dark matter halos surrounding galaxies. And this is just what this new image is thought to show. A press release that described it said:

In the early universe, filaments of dark matter could have created a large web that entangled gas through their gravitational pull. Once gas accumulated at the intersection between filaments, it would have provided the fuel necessary to form galaxies.

The researchers said their image:

opens a new avenue to constrain the physical properties of the cosmic web and to trace the distribution of dark matter on large scales.

Bottom line: A new image from ESO’s Very Large Telescope provides what these astronomers called “our clearest view yet” of a filament in the cosmic web.

Source: High-definition imaging of a filamentary connection between a close quasar pair at z = 3

Via ESO

The post A filament of the cosmic web! Clearest image yet first appeared on EarthSky.



from EarthSky https://ift.tt/4iu8kdF
Cosmic web: A starfield with purple blobs thicker at 2 ends with thinner material stretching between.
This new image from the European Southern Observatory’s Very Large Telescope in Chile provides our clearest view yet of a filament in the cosmic web. The cosmic web is a network of filaments and voids that make up the large-scale structure of the universe. It’s composed primarily of invisible dark matter. But, in this image, the purple glow traces a gas bridge between distant galaxies. This gas clumped together thanks to dark matter’s influence. Image via ESO/ D. Tornotti et al./ Hubble: M. Revalski, P. Francis et al.

A glimpse of the cosmic web

Astronomers speak of the cosmic web as the most fundamental, large-scale structure of our universe. They picture it as a network of filaments and voids – spanning untold billions of light-years – whose skeleton is formed primarily by invisible dark matter. And, although we can’t see it, astronomers estimate that some 85% of all matter in our universe is dark matter. So it seems logical, but how can we know for sure that the cosmic web is even there?

The answer is that we see dark matter’s influence on other components of our universe. In the case of this image, we see a bridge of gas stretched between two distant galaxies in the early universe. The European Southern Observatory (ESO) shared this image on January 29, 2025. They said it represents the “clearest image yet” of a filament of the cosmic web.

The researchers published their peer-reviewed study of this image on January 29, in the journal Nature Astronomy.

Bridging 2 galaxies

The starfield in the background of the image is from the Hubble Space Telescope. But look more closely. You might be able to see a fuzziness to many of these “stars,” which – except for a few bright spiky objects – aren’t stars at all, but instead distant galaxies. The purple color is an overlay of the location of gas that has clumped together, thanks to the influence of dark matter.

The two larger concentrations center on galaxies, while the thin filament between them represents a bridge of material.

This filament of the cosmic web is huge! It’s some 3 million light-years long. The researchers found this faint bridge of glowing gas by making 150 hours of observations with the MUSE instrument on ESO’s Very Large Telescope in Chile.

Lead author Davide Tornotti of the University of Milano-Bicocca in Italy led the team that conducted the high-definition imaging of the filament. The filament was located at a redshift of what astronomers call z = 3, which is equivalent to a distance from Earth of more than 11 billion light-years.

A prediction of cold dark matter theory

The discovery is a boost to the prevailing model used by scientists to understand how our universe works and fits together. That model is called the Lambda CDM model, for Lambda cold dark matter. It’s a mathematical model, integrated into the Big Bang theory. The model suggests that dark matter consists of particles moving much more slowly than the speed of light. Many (but not all) astronomers feel that this still-hypothetical type of dark matter is the best fit with what we see in the universe so far. It explains how the smooth early cosmos turned into the clumps and then structures – such as galaxies – that we see today.

One long-standing prediction of the Lambda CDM model involves the idea of filaments between the dark matter halos surrounding galaxies. And this is just what this new image is thought to show. A press release that described it said:

In the early universe, filaments of dark matter could have created a large web that entangled gas through their gravitational pull. Once gas accumulated at the intersection between filaments, it would have provided the fuel necessary to form galaxies.

The researchers said their image:

opens a new avenue to constrain the physical properties of the cosmic web and to trace the distribution of dark matter on large scales.

Bottom line: A new image from ESO’s Very Large Telescope provides what these astronomers called “our clearest view yet” of a filament in the cosmic web.

Source: High-definition imaging of a filamentary connection between a close quasar pair at z = 3

Via ESO

The post A filament of the cosmic web! Clearest image yet first appeared on EarthSky.



from EarthSky https://ift.tt/4iu8kdF

Juno spots most extreme volcanic activity on Io to date

Gray sphere with grid lines. Patches and dots of very bright light on it, with one very bright near the pole.
This image, taken by the Jovian Infrared Auroral Mapper (JIRAM) infrared imager aboard NASA’s Juno spacecraft on December 27, 2024, highlights volcanic activity on Io, one of Jupiter’s moons. A massive hotspot – larger than Earth’s Lake Superior – can be seen just to the right of Io’s south pole. Image via NASA/ JPL-Caltech/ SwRI/ ASI/ INAF/ JIRAM.
  • Jupiter’s moon Io is highly volcanically active, with around 400 volcanoes on its surface.
  • On its most recent flyby of Io, NASA’s Juno spacecraft detected the most intense volcanic activity ever seen on the Jovian moon.
  • The eruption likely left long-term signatures on Io, which Juno will investigate during an upcoming flyby.

NASA published this original article on January 28, 2025. Edits by EarthSky.

Extreme volcanic activity on Io

During a flyby of Jupiter’s moon Io on December 27, 2024, NASA’s Juno spacecraft discovered an astonishing volcanic hotspot in the moon’s southern hemisphere. The hotspot is not only larger than Earth’s Lake Superior (the largest freshwater lake in the world by surface area), but it also belches out eruptions with six times the total energy of all the world’s power plants. Even by Io’s intense standards – as the most volcanic celestial body in the solar system – its recent activity has been extreme.

Juno’s principal investigator Scott Bolton of the Southwest Research Institute in San Antonio, Texas, said:

The data from this latest flyby really blew our minds. This is the most powerful volcanic event ever recorded on the most volcanic world in our solar system; so that’s really saying something.

The 2025 EarthSky lunar calendar makes a great gift. Get yours today!

Half a tan-colored sphere with dozens of small, round dark spots on it.
The Juno spacecraft acquired this closeup image of Io on December 30, 2023. It was its 57th perijove, or close flyby to Jupiter, since entering orbit around the giant planet on July 4, 2016. Some of the pockmarks are active volcanos. Image via NASA.

Io: A tormented, volcanic world

The source of Io’s torment is Jupiter. Io is about the size of Earth’s moon, and orbits extremely close to the mammoth gas giant. And it whips around Jupiter once every 42.5 hours in an elliptical (oval-shaped) orbit. As the distance to Jupiter varies, so does the planet’s gravitational pull, which leads to the moon being relentlessly squeezed.

The result: immense energy from frictional heating. This melts portions of Io’s interior, resulting in a seemingly endless series of lava plumes and ash venting into its atmosphere from the estimated 400 volcanoes that riddle its surface.

Juno’s close flybys reveal volcanic activity on Io

The discovery of this recent activity comes courtesy of Juno’s Jovian Infrared Auroral Mapper (JIRAM) instrument, contributed by the Italian Space Agency. Designed to capture the infrared light (which isn’t visible to the human eye) emerging from deep inside Jupiter, JIRAM has probed the gas giant’s weather layer, peering 30 to 45 miles (48 to 72 kilometers) below its cloud tops. But since NASA extended Juno’s mission, the team has also used the instrument to study the moons Io, Europa, Ganymede, and Callisto.

During its extended mission, Juno’s trajectory passes by Io every other orbit, flying over the same part of the moon each time. Previously, the spacecraft made close flybys of Io in December 2023 and February 2024, getting within about 930 miles (1,500 kilometers) of its surface. The latest flyby took place on December 27, 2024, bringing the spacecraft within about 46,200 miles (74,400 kilometers) of the moon, with the infrared instrument trained on Io’s southern hemisphere.

Red sphere, partly in shadow, on black background. There are many small, very bright spots on its surface.
View larger. | Juno captured this stunning infrared view of Io and its many volcanoes on July 5, 2022. Image via NASA/ JPL-Caltech/ SwRI/ ASI/ INAF/ JIRAM.

Io brings the heat

Alessandro Mura, a Juno co-investigator from the National Institute for Astrophysics in Rome, said:

JIRAM detected an event of extreme infrared radiance — a massive hotspot — in Io’s southern hemisphere, so strong that it saturated our detector. However, we have evidence what we detected is actually a few closely spaced hotspots that emitted at the same time, suggestive of a subsurface vast magma chamber system. The data support that this is the most intense volcanic eruption ever recorded on Io.

The JIRAM science team estimates the as-yet-unnamed feature spans 40,000 square miles (100,000 square kilometers). The previous record holder was Io’s Loki Patera, a lava lake of about 7,700 square miles (20,000 square kilometers). The total power value of the new hotspot’s radiance measured well above 80 trillion watts.

Three images of a rusty brown and white moon. Purple arrows point to the same spot on each.
Images of Io captured in 2024 by the JunoCam imager aboard NASA’s Juno show significant and visible surface changes (indicated by the arrows) near the Jovian moon’s south pole. These changes occurred between the 66th and 68th perijove (the point during Juno’s orbit when it is closest to Jupiter). Image via NASA/ JPL-Caltech/ SwRI/ MSSS/ Jason Perry.

Volcanic activity on Io leaves a mark

The feature was also captured by the mission’s JunoCam visible light camera. The team compared JunoCam images from the two previous Io flybys with those the instrument collected on December 27. And while these most recent images are of lower resolution since Juno was farther away, the relative changes in surface coloring around the newly discovered hotspot are clear. Such changes in Io’s surface are known to be associated with hotspots and volcanic activity.

An eruption of this magnitude is likely to leave long-lived signatures. Other large eruptions on Io have created varied features, such as pyroclastic deposits (composed of rock fragments spewed out by a volcano), small lava flows that may be fed by fissures, and volcanic-plume deposits rich in sulfur and sulfur dioxide.

Juno will use an upcoming, more distant flyby of Io on March 3 to look at the hotspot again and search for changes in the landscape. Earth-based observations of this region of the moon may also be possible.

Bolton said:

While it is always great to witness events that rewrite the record books, this new hotspot can potentially do much more. The intriguing feature could improve our understanding of volcanism not only on Io but on other worlds as well.

Bottom line: On its most recent flyby, the Juno spacecraft spotted intense volcanic activity on Io, one of Jupiter’s moons. It was the most extreme volcanism ever seen on Io.

Via NASA

Read more: Io’s raging volcanoes are self-powered

Read more: Lava lakes on Io: Juno zooms in on Io’s volcanoes

The post Juno spots most extreme volcanic activity on Io to date first appeared on EarthSky.



from EarthSky https://ift.tt/OSvIwsc
Gray sphere with grid lines. Patches and dots of very bright light on it, with one very bright near the pole.
This image, taken by the Jovian Infrared Auroral Mapper (JIRAM) infrared imager aboard NASA’s Juno spacecraft on December 27, 2024, highlights volcanic activity on Io, one of Jupiter’s moons. A massive hotspot – larger than Earth’s Lake Superior – can be seen just to the right of Io’s south pole. Image via NASA/ JPL-Caltech/ SwRI/ ASI/ INAF/ JIRAM.
  • Jupiter’s moon Io is highly volcanically active, with around 400 volcanoes on its surface.
  • On its most recent flyby of Io, NASA’s Juno spacecraft detected the most intense volcanic activity ever seen on the Jovian moon.
  • The eruption likely left long-term signatures on Io, which Juno will investigate during an upcoming flyby.

NASA published this original article on January 28, 2025. Edits by EarthSky.

Extreme volcanic activity on Io

During a flyby of Jupiter’s moon Io on December 27, 2024, NASA’s Juno spacecraft discovered an astonishing volcanic hotspot in the moon’s southern hemisphere. The hotspot is not only larger than Earth’s Lake Superior (the largest freshwater lake in the world by surface area), but it also belches out eruptions with six times the total energy of all the world’s power plants. Even by Io’s intense standards – as the most volcanic celestial body in the solar system – its recent activity has been extreme.

Juno’s principal investigator Scott Bolton of the Southwest Research Institute in San Antonio, Texas, said:

The data from this latest flyby really blew our minds. This is the most powerful volcanic event ever recorded on the most volcanic world in our solar system; so that’s really saying something.

The 2025 EarthSky lunar calendar makes a great gift. Get yours today!

Half a tan-colored sphere with dozens of small, round dark spots on it.
The Juno spacecraft acquired this closeup image of Io on December 30, 2023. It was its 57th perijove, or close flyby to Jupiter, since entering orbit around the giant planet on July 4, 2016. Some of the pockmarks are active volcanos. Image via NASA.

Io: A tormented, volcanic world

The source of Io’s torment is Jupiter. Io is about the size of Earth’s moon, and orbits extremely close to the mammoth gas giant. And it whips around Jupiter once every 42.5 hours in an elliptical (oval-shaped) orbit. As the distance to Jupiter varies, so does the planet’s gravitational pull, which leads to the moon being relentlessly squeezed.

The result: immense energy from frictional heating. This melts portions of Io’s interior, resulting in a seemingly endless series of lava plumes and ash venting into its atmosphere from the estimated 400 volcanoes that riddle its surface.

Juno’s close flybys reveal volcanic activity on Io

The discovery of this recent activity comes courtesy of Juno’s Jovian Infrared Auroral Mapper (JIRAM) instrument, contributed by the Italian Space Agency. Designed to capture the infrared light (which isn’t visible to the human eye) emerging from deep inside Jupiter, JIRAM has probed the gas giant’s weather layer, peering 30 to 45 miles (48 to 72 kilometers) below its cloud tops. But since NASA extended Juno’s mission, the team has also used the instrument to study the moons Io, Europa, Ganymede, and Callisto.

During its extended mission, Juno’s trajectory passes by Io every other orbit, flying over the same part of the moon each time. Previously, the spacecraft made close flybys of Io in December 2023 and February 2024, getting within about 930 miles (1,500 kilometers) of its surface. The latest flyby took place on December 27, 2024, bringing the spacecraft within about 46,200 miles (74,400 kilometers) of the moon, with the infrared instrument trained on Io’s southern hemisphere.

Red sphere, partly in shadow, on black background. There are many small, very bright spots on its surface.
View larger. | Juno captured this stunning infrared view of Io and its many volcanoes on July 5, 2022. Image via NASA/ JPL-Caltech/ SwRI/ ASI/ INAF/ JIRAM.

Io brings the heat

Alessandro Mura, a Juno co-investigator from the National Institute for Astrophysics in Rome, said:

JIRAM detected an event of extreme infrared radiance — a massive hotspot — in Io’s southern hemisphere, so strong that it saturated our detector. However, we have evidence what we detected is actually a few closely spaced hotspots that emitted at the same time, suggestive of a subsurface vast magma chamber system. The data support that this is the most intense volcanic eruption ever recorded on Io.

The JIRAM science team estimates the as-yet-unnamed feature spans 40,000 square miles (100,000 square kilometers). The previous record holder was Io’s Loki Patera, a lava lake of about 7,700 square miles (20,000 square kilometers). The total power value of the new hotspot’s radiance measured well above 80 trillion watts.

Three images of a rusty brown and white moon. Purple arrows point to the same spot on each.
Images of Io captured in 2024 by the JunoCam imager aboard NASA’s Juno show significant and visible surface changes (indicated by the arrows) near the Jovian moon’s south pole. These changes occurred between the 66th and 68th perijove (the point during Juno’s orbit when it is closest to Jupiter). Image via NASA/ JPL-Caltech/ SwRI/ MSSS/ Jason Perry.

Volcanic activity on Io leaves a mark

The feature was also captured by the mission’s JunoCam visible light camera. The team compared JunoCam images from the two previous Io flybys with those the instrument collected on December 27. And while these most recent images are of lower resolution since Juno was farther away, the relative changes in surface coloring around the newly discovered hotspot are clear. Such changes in Io’s surface are known to be associated with hotspots and volcanic activity.

An eruption of this magnitude is likely to leave long-lived signatures. Other large eruptions on Io have created varied features, such as pyroclastic deposits (composed of rock fragments spewed out by a volcano), small lava flows that may be fed by fissures, and volcanic-plume deposits rich in sulfur and sulfur dioxide.

Juno will use an upcoming, more distant flyby of Io on March 3 to look at the hotspot again and search for changes in the landscape. Earth-based observations of this region of the moon may also be possible.

Bolton said:

While it is always great to witness events that rewrite the record books, this new hotspot can potentially do much more. The intriguing feature could improve our understanding of volcanism not only on Io but on other worlds as well.

Bottom line: On its most recent flyby, the Juno spacecraft spotted intense volcanic activity on Io, one of Jupiter’s moons. It was the most extreme volcanism ever seen on Io.

Via NASA

Read more: Io’s raging volcanoes are self-powered

Read more: Lava lakes on Io: Juno zooms in on Io’s volcanoes

The post Juno spots most extreme volcanic activity on Io to date first appeared on EarthSky.



from EarthSky https://ift.tt/OSvIwsc

Lunar New Year 2025: The Year of the Snake

White circle on black background with symbol in Chinese and the image of a curled up snake.
The snake is the 6th of 12 animals in the Chinese zodiac that are use in the Chinese Lunar Calendar. The Lunar New Year 2025 is the Year of the Snake. Image via Wikipedia. Used with permission.

Over a billion people in China and millions around the world will celebrate the Lunar New Year starting today. The start of the holiday coincides with the time of the new moon, which will fall at 12:36 UTC on Wednesday, January 29, 2025. That’s equivalent to 8:36 p.m. Wednesday evening in Beijing. The Lunar New Year is a time to honor deities and ancestors and to be with family. This year, it’s the Year of the Snake.

The Year of the Dragon will end on January 28, 2025. And then the Year of the Snake will start on January 29, 2025. Next comes the year of the Horse, starting on February 17, 2026.

Available now! 2025 EarthSky lunar calendar. A unique and beautiful poster-sized calendar showing phases of the moon every night of the year! And it makes a great gift.

Lunar New Year: People in red and yellow carry a dragon float over their heads through a street lined with festive onlookers.
The largest Lunar New Year parade outside of Asia typically occurs in Chinatown, Manhattan, New York. In 2025, the parade is on February 16. Image via Patrick Kwan/ Wikimedia Commons (CC BY 2.0).

The calendar and Lunar New Year

In China, the familiar Gregorian calendar is used for day-to-day life. But Chinese calendar dates continue to be used to mark traditional holidays such as the new year and the fall moon festival. And then Chinese astrology uses the lunar calendar to determine favorable dates for weddings and other special events.

In other words, the Chinese calendar is a lunisolar calendar, a combination of solar and lunar calendars. Plus, it has a long history spanning several Chinese dynastic periods from as far back as the Shang Dynasty around the 14th century BCE. Also, there are several different symbolic cycles within the calendar, used in Chinese astrology.

So the Chinese calendar is an intricate and complex measure of time.

The Chinese calendar is based on a lunar cycle

A month in the Chinese calendar spans a single lunar cycle. In fact, the first day of the month begins during the new moon, when no sunlight falls on the lunar hemisphere that faces Earth. So, a lunar cycle, on average, lasts 29.5 days.

And a lunar month can last 29 or 30 days. As a result, there are usually 12 lunar months in a Chinese calendar year. In order to catch up with the solar calendar, which averages 365.25 days in a year, an extra month is added to the Chinese calendar every two or three years. As a result, Lunar New Year falls on different dates each year (in the Gregorian calendar) between January 21 and February 21.

Two large blue Chinese characters on a red background.
Our friend Matthew Chin in Hong Kong created this graphic and wrote: “The 2 Chinese characters are the same. It means blessing, a hope that other people will get good luck. Blessings like these are commonly used during Lunar New Year. The red background is also a kind of good as Chinese people use red to represent good luck.” Thank you, Matthew!

2025 is the Year of the Snake

One of 12 animal symbols of the Chinese zodiac (Rat, Ox, Tiger, Rabbit, Dragon, Snake, Horse, Sheep/Goat, Monkey, Rooster, Dog and Boar/Pig) represent each year of the Chinese lunar calendar. For 2025, it’s the Year of the Snake. TravelChinaGuide.com says:

Snake carries the meanings of malevolence, cattiness, mystery, as well as acumen and divination. In most cases, this animal is considered evil and the elongated legless body always scares people. However, in ancient Chinese traditions, the snake once presented a venerated image and it is one of the earliest totems of Chinese nations. Chinese mother goddess Nüwa who said to have created humanity has the body of a snake and the head of a human. The Chinese dragon also has a snake body. Today, in some places in China, people still believe that a snake found in their courtyard can bring good luck.

People born in the Year of the Snake are considered rational, calm, thoughtful, and loyal to the loved ones.

How to celebrate Lunar New Year

Lunar New Year: Fireworks over a glittering nighttime city skyline with water in the foreground.
Fireworks display celebrating the Lunar New Year over Victoria Harbor in Hong Kong. Image via Michael Elleray/ Wikimedia Commons (CC BY 2.0).

From the first day of the Lunar New Year (the day of the new moon) to the 15th day (next full moon), Lunar New Year celebrations abound. What’s more, each day holds a special significance that varies according to local traditions. But first, before the arrival of the new year, homes are thoroughly cleaned to sweep away ill fortune and to welcome good luck. Then on New Year’s Eve, families traditionally gather to celebrate and enjoy sumptuous traditional feasts. Finally, at midnight, they greet the new year with fireworks.

In the days that follow, celebrations include a variety of festivities. For example, there are dance parades featuring colorful dragons or lions. Or there are ceremonies to pay homage to deities and ancestors. Plus, children receive money in red envelopes and gifts are exchanged. Extended family members travel long distances to visit each other.

The Lunar New Year celebration traditionally culminates on the 15th day with the Lantern Festival. On this night of the full moon, families mingle in the streets carrying lighted lanterns, often creating a beautiful light display.

Many glowing lanterns hung above a street at night.
Lantern festival in Shanghai, China. Image via North sea deamer/ Wikimedia Commons (CC BY-SA 3.0).

Folklore and Lunar New Year

There are several variations on the mythology behind Lunar New Year celebrations. Most concern the story of an ugly, bloodthirsty monster named Nian. The monster would emerge on the last night of each year to destroy villages and eat people. A wise elder advised villagers to scare the monster away with loud noises. That night, they set fire to bamboo, lit fireworks, and banged their drums. So the monster, afraid of the loud noises and lights, ran away to hide in its cave.

In another version of the myth, an old man persuaded Nian to turn its wrath on other monsters, not the villagers. Before he was seen riding away on Nian, the old man, actually a god, advised the people to hang red paper decorations in their homes and set off firecrackers on the last night of the year to keep Nian away.

Then on the first day of the new year, the villagers celebrated, greeting each other with the words Guo Nian, which mean “survive the Nian.” That tradition has continued to this day, with Guo Nian now meaning “celebrate the new year.”

The world’s biggest New Year celebration

Historically, the Lunar New Year signals the arrival of the world’s largest annual human migration.

Bottom line: The Lunar New Year falls on January 29, 2025. It coincides with the date of new moon and signals the start of the Year of the Snake.

The post Lunar New Year 2025: The Year of the Snake first appeared on EarthSky.



from EarthSky https://ift.tt/i6ORstG
White circle on black background with symbol in Chinese and the image of a curled up snake.
The snake is the 6th of 12 animals in the Chinese zodiac that are use in the Chinese Lunar Calendar. The Lunar New Year 2025 is the Year of the Snake. Image via Wikipedia. Used with permission.

Over a billion people in China and millions around the world will celebrate the Lunar New Year starting today. The start of the holiday coincides with the time of the new moon, which will fall at 12:36 UTC on Wednesday, January 29, 2025. That’s equivalent to 8:36 p.m. Wednesday evening in Beijing. The Lunar New Year is a time to honor deities and ancestors and to be with family. This year, it’s the Year of the Snake.

The Year of the Dragon will end on January 28, 2025. And then the Year of the Snake will start on January 29, 2025. Next comes the year of the Horse, starting on February 17, 2026.

Available now! 2025 EarthSky lunar calendar. A unique and beautiful poster-sized calendar showing phases of the moon every night of the year! And it makes a great gift.

Lunar New Year: People in red and yellow carry a dragon float over their heads through a street lined with festive onlookers.
The largest Lunar New Year parade outside of Asia typically occurs in Chinatown, Manhattan, New York. In 2025, the parade is on February 16. Image via Patrick Kwan/ Wikimedia Commons (CC BY 2.0).

The calendar and Lunar New Year

In China, the familiar Gregorian calendar is used for day-to-day life. But Chinese calendar dates continue to be used to mark traditional holidays such as the new year and the fall moon festival. And then Chinese astrology uses the lunar calendar to determine favorable dates for weddings and other special events.

In other words, the Chinese calendar is a lunisolar calendar, a combination of solar and lunar calendars. Plus, it has a long history spanning several Chinese dynastic periods from as far back as the Shang Dynasty around the 14th century BCE. Also, there are several different symbolic cycles within the calendar, used in Chinese astrology.

So the Chinese calendar is an intricate and complex measure of time.

The Chinese calendar is based on a lunar cycle

A month in the Chinese calendar spans a single lunar cycle. In fact, the first day of the month begins during the new moon, when no sunlight falls on the lunar hemisphere that faces Earth. So, a lunar cycle, on average, lasts 29.5 days.

And a lunar month can last 29 or 30 days. As a result, there are usually 12 lunar months in a Chinese calendar year. In order to catch up with the solar calendar, which averages 365.25 days in a year, an extra month is added to the Chinese calendar every two or three years. As a result, Lunar New Year falls on different dates each year (in the Gregorian calendar) between January 21 and February 21.

Two large blue Chinese characters on a red background.
Our friend Matthew Chin in Hong Kong created this graphic and wrote: “The 2 Chinese characters are the same. It means blessing, a hope that other people will get good luck. Blessings like these are commonly used during Lunar New Year. The red background is also a kind of good as Chinese people use red to represent good luck.” Thank you, Matthew!

2025 is the Year of the Snake

One of 12 animal symbols of the Chinese zodiac (Rat, Ox, Tiger, Rabbit, Dragon, Snake, Horse, Sheep/Goat, Monkey, Rooster, Dog and Boar/Pig) represent each year of the Chinese lunar calendar. For 2025, it’s the Year of the Snake. TravelChinaGuide.com says:

Snake carries the meanings of malevolence, cattiness, mystery, as well as acumen and divination. In most cases, this animal is considered evil and the elongated legless body always scares people. However, in ancient Chinese traditions, the snake once presented a venerated image and it is one of the earliest totems of Chinese nations. Chinese mother goddess Nüwa who said to have created humanity has the body of a snake and the head of a human. The Chinese dragon also has a snake body. Today, in some places in China, people still believe that a snake found in their courtyard can bring good luck.

People born in the Year of the Snake are considered rational, calm, thoughtful, and loyal to the loved ones.

How to celebrate Lunar New Year

Lunar New Year: Fireworks over a glittering nighttime city skyline with water in the foreground.
Fireworks display celebrating the Lunar New Year over Victoria Harbor in Hong Kong. Image via Michael Elleray/ Wikimedia Commons (CC BY 2.0).

From the first day of the Lunar New Year (the day of the new moon) to the 15th day (next full moon), Lunar New Year celebrations abound. What’s more, each day holds a special significance that varies according to local traditions. But first, before the arrival of the new year, homes are thoroughly cleaned to sweep away ill fortune and to welcome good luck. Then on New Year’s Eve, families traditionally gather to celebrate and enjoy sumptuous traditional feasts. Finally, at midnight, they greet the new year with fireworks.

In the days that follow, celebrations include a variety of festivities. For example, there are dance parades featuring colorful dragons or lions. Or there are ceremonies to pay homage to deities and ancestors. Plus, children receive money in red envelopes and gifts are exchanged. Extended family members travel long distances to visit each other.

The Lunar New Year celebration traditionally culminates on the 15th day with the Lantern Festival. On this night of the full moon, families mingle in the streets carrying lighted lanterns, often creating a beautiful light display.

Many glowing lanterns hung above a street at night.
Lantern festival in Shanghai, China. Image via North sea deamer/ Wikimedia Commons (CC BY-SA 3.0).

Folklore and Lunar New Year

There are several variations on the mythology behind Lunar New Year celebrations. Most concern the story of an ugly, bloodthirsty monster named Nian. The monster would emerge on the last night of each year to destroy villages and eat people. A wise elder advised villagers to scare the monster away with loud noises. That night, they set fire to bamboo, lit fireworks, and banged their drums. So the monster, afraid of the loud noises and lights, ran away to hide in its cave.

In another version of the myth, an old man persuaded Nian to turn its wrath on other monsters, not the villagers. Before he was seen riding away on Nian, the old man, actually a god, advised the people to hang red paper decorations in their homes and set off firecrackers on the last night of the year to keep Nian away.

Then on the first day of the new year, the villagers celebrated, greeting each other with the words Guo Nian, which mean “survive the Nian.” That tradition has continued to this day, with Guo Nian now meaning “celebrate the new year.”

The world’s biggest New Year celebration

Historically, the Lunar New Year signals the arrival of the world’s largest annual human migration.

Bottom line: The Lunar New Year falls on January 29, 2025. It coincides with the date of new moon and signals the start of the Year of the Snake.

The post Lunar New Year 2025: The Year of the Snake first appeared on EarthSky.



from EarthSky https://ift.tt/i6ORstG

New Blue Marble image from Blue Ghost spacecraft

The Earth, all blue and white, hanging in black space like a blue marble.
Firefly Aerospace’s Blue Ghost spacecraft captures the Blue Marble while in Earth orbit approximately 4,200 miles (6,700 km) above the planet on January 23, 2025. Via Firefly Aerospace. Used with permission.

Firefly Aerospace’s Blue Ghost spacecraft captured its own version of the iconic Blue Marble image on January 23, 2025. And doesn’t our planet look as beautiful as ever? The craft captured the shot from 4,200 miles (6,700 km) above Earth, while orbiting Earth ahead of its journey to the moon early next month. Blue Ghost launched on January 15, 2025, and is expected to reach the lunar surface on March 2, 2025.

When it reaches the moon, Blue Ghost’s will perform an array of science tasks. It will take soil samples, investigate heat flow beneath the lunar crust, test a radiation-resistant computer and much more. And it will also gaze back at Earth again, taking X-ray images of our planet’s magnetosphere.


This video was captured during one of Blue Ghost’s engine burns, when the spacecraft fired its thrusters to adjust its orbit around our planet.

The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Get yours today!

On its way to the moon

Blue Ghost is currently in high orbit around Earth. It’s spending the first 25 days after its January 15 launch in Earth orbit, gradually changing its trajectory until it can swing out from our planet’s gravitational pull and make a four-day journey to lunar orbit. After 16 days orbiting the moon, it should finally be able to land on its surface on March 2, 2025. It will then finally begin 14 days of science operations.

Firefly Aeronautics wrote:

Blue Ghost captured the beauty of our home planet during another Earth orbit burn. This second engine burn (and first critical burn) adjusted Blue Ghost’s apogee (the farthest point from Earth) using just our Spectre RCS thrusters. With just over two weeks left in Earth orbit before our trans-lunar injection [the maneuver that takes a spacecraft from Earth orbit to moon orbit], our team will continue operating our NASA payloads onboard and capturing science data along the way!

Diagram of Earth and moon with lines for orbits around each and path from Earth to moon.
View larger. | Firefly Aerospace published this diagram showing the Blue Ghost spacecraft’s trajectory to the moon after its January 15, 2025, launch. The lunar lander is scheduled to land on the moon on March 2.
The Earth, mostly blue with swirling white cloud and some brownish land showing.
Apollo 17 astronauts took this original Blue Marble image in 1972. Image via NASA.

Bottom line: Firefly Aeronautics’ Blue Ghost lunar spacecraft took this “Blue Marble” image of Earth from orbit around our planet.

The post New Blue Marble image from Blue Ghost spacecraft first appeared on EarthSky.



from EarthSky https://ift.tt/5ZUK03u
The Earth, all blue and white, hanging in black space like a blue marble.
Firefly Aerospace’s Blue Ghost spacecraft captures the Blue Marble while in Earth orbit approximately 4,200 miles (6,700 km) above the planet on January 23, 2025. Via Firefly Aerospace. Used with permission.

Firefly Aerospace’s Blue Ghost spacecraft captured its own version of the iconic Blue Marble image on January 23, 2025. And doesn’t our planet look as beautiful as ever? The craft captured the shot from 4,200 miles (6,700 km) above Earth, while orbiting Earth ahead of its journey to the moon early next month. Blue Ghost launched on January 15, 2025, and is expected to reach the lunar surface on March 2, 2025.

When it reaches the moon, Blue Ghost’s will perform an array of science tasks. It will take soil samples, investigate heat flow beneath the lunar crust, test a radiation-resistant computer and much more. And it will also gaze back at Earth again, taking X-ray images of our planet’s magnetosphere.


This video was captured during one of Blue Ghost’s engine burns, when the spacecraft fired its thrusters to adjust its orbit around our planet.

The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Get yours today!

On its way to the moon

Blue Ghost is currently in high orbit around Earth. It’s spending the first 25 days after its January 15 launch in Earth orbit, gradually changing its trajectory until it can swing out from our planet’s gravitational pull and make a four-day journey to lunar orbit. After 16 days orbiting the moon, it should finally be able to land on its surface on March 2, 2025. It will then finally begin 14 days of science operations.

Firefly Aeronautics wrote:

Blue Ghost captured the beauty of our home planet during another Earth orbit burn. This second engine burn (and first critical burn) adjusted Blue Ghost’s apogee (the farthest point from Earth) using just our Spectre RCS thrusters. With just over two weeks left in Earth orbit before our trans-lunar injection [the maneuver that takes a spacecraft from Earth orbit to moon orbit], our team will continue operating our NASA payloads onboard and capturing science data along the way!

Diagram of Earth and moon with lines for orbits around each and path from Earth to moon.
View larger. | Firefly Aerospace published this diagram showing the Blue Ghost spacecraft’s trajectory to the moon after its January 15, 2025, launch. The lunar lander is scheduled to land on the moon on March 2.
The Earth, mostly blue with swirling white cloud and some brownish land showing.
Apollo 17 astronauts took this original Blue Marble image in 1972. Image via NASA.

Bottom line: Firefly Aeronautics’ Blue Ghost lunar spacecraft took this “Blue Marble” image of Earth from orbit around our planet.

The post New Blue Marble image from Blue Ghost spacecraft first appeared on EarthSky.



from EarthSky https://ift.tt/5ZUK03u

Asteroid 2024 YR4 has non-zero odds of hitting Earth

Asteroid 2024 YR4: Distant Earth in space with a gray, irregular, cratered rocky object in foreground.
Artist’s illustration of an asteroid approaching Earth. The Catalina Sky Survey discovered an asteroid on December 25, 2024, that – as of January 27, 2025 – has 1-in-83 odds of hitting Earth in 2032. Read more about asteroid 2024 YR4 below. Image via urikyo33/ Pixabay.

Asteroid 2024 YR4 has a chance of hitting Earth

The Catalina Sky Survey first discovered asteroid 2024 YR4 on December 25, 2024. As of January 27, 2025, the current estimates were that the space rock has a 1 in 83 odds of hitting Earth in 2032. The asteroid is about 150 feet or 50 meters wide. The International Astronomical Union (IAU) keeps what it calls the Torino Impact Hazard Scale to rate the risk of asteroids making close encounters with Earth. Asteroid 2024 YR4 has a current value of 3 on the Torino scale. At this time, it is the only asteroid with a value above zero.

The only asteroid ever to have a higher score on the Torino scale was 99942 Apophis. Apophis briefly had a rating of four in late 2004.

The asteroid isn’t large enough to end life on Earth as we know it, but it could be locally destructive, depending on where it hit. (Watch a video of size comparisons in asteroids.) The asteroid is similar in size to the one that felled a forest near Tunguska, Siberia, in 1908.

Star chart showing stars with labels and location of asteroid at center.
This was the location of asteroid 2024 YR4 as on January 27, 2025. Currently it’s in the direction of the star Procyon in Canis Minor. However it’s incredibly dim at magnitude 23. Image via TheSkyLive.

What is the Torino scale?

The IAU has been using the Torino Impact Hazard Scale since 1999 to categorize asteroids that could potentially hit Earth. An object – such as 2024 YR4 – with a score of 3 puts in the yellow zone. This means the object merits attention by astronomers:

A close encounter, meriting attention by astronomers. Current calculations give a 1% or greater chance of collision capable of localized destruction. Most likely, new telescopic observations will lead to re-assignment to Level 0. Attention by public and by public officials is merited if the encounter is less than a decade away.

In fact, most new asteroids that get listed on the Torino scale have their likelihood of hitting Earth go up with more observations … until it drops to zero. That’s because the uncertain path of the asteroid is wide and more observations shrinks the path, making it look more likely, until the path shrinks enough to show that it will not cross Earth’s. It’s likely that’s what will happen with asteroid 2024 YR4 also.

In 2023, EarthSky spoke with the inventor of the Torino scale, Richard Binzel of the Massachusetts Institute of Technology. He said that we should expect more objects to make the Torino scale as our technology improves, allowing us to see smaller objects we otherwise would have missed. So, we had better get used to seeing objects on the Torino scale, at least temporarily.

How is asteroid 2024 different?

Asteroid 2024 YR4 presents a challenge to observations, however. The potential for an impact is still seven years away, but the asteroid is moving into a position where astronomers will not be able to observe it for about three years. At the moment the asteroid is magnitude 23 and will continue to dim through February until it leaves our view. So we may not get enough observations to remove the asteroid from where it currently sits on the Torino scale for a few years.

With the current data astronomers have on the asteroid, they estimate not just one possibility for impact in 2032, but seven possibilities between 2032 and 2079. The first possible impact date is December 22, 2032. Again, as more observations come in, this information will change.

Future observations

So, what if further observations of asteroid 2024 YR4 determine that it is on a collision course with Earth on December 22, 2032? To start with, the first potential impact is still years away. And we’ve already sent a mission to hit and move an asteroid as a test of our planetary defense system. That mission was the Double Asteroid Redirection Test (DART), which impacted with an asteroid’s moon named Dimorphos in 2022. And Dimorphos was much larger than asteroid 2024 YR4, at 525 feet (160 meters) across.

Bottom line: Astronomers discovered an asteroid in December that has a 1-in-83 chance of hitting Earth in 2032. The asteroid 2024 YR4 is about 150 feet (50 m) wide.

Via IAU Minor Planet Center

Via ESA

The post Asteroid 2024 YR4 has non-zero odds of hitting Earth first appeared on EarthSky.



from EarthSky https://ift.tt/VmR9yex
Asteroid 2024 YR4: Distant Earth in space with a gray, irregular, cratered rocky object in foreground.
Artist’s illustration of an asteroid approaching Earth. The Catalina Sky Survey discovered an asteroid on December 25, 2024, that – as of January 27, 2025 – has 1-in-83 odds of hitting Earth in 2032. Read more about asteroid 2024 YR4 below. Image via urikyo33/ Pixabay.

Asteroid 2024 YR4 has a chance of hitting Earth

The Catalina Sky Survey first discovered asteroid 2024 YR4 on December 25, 2024. As of January 27, 2025, the current estimates were that the space rock has a 1 in 83 odds of hitting Earth in 2032. The asteroid is about 150 feet or 50 meters wide. The International Astronomical Union (IAU) keeps what it calls the Torino Impact Hazard Scale to rate the risk of asteroids making close encounters with Earth. Asteroid 2024 YR4 has a current value of 3 on the Torino scale. At this time, it is the only asteroid with a value above zero.

The only asteroid ever to have a higher score on the Torino scale was 99942 Apophis. Apophis briefly had a rating of four in late 2004.

The asteroid isn’t large enough to end life on Earth as we know it, but it could be locally destructive, depending on where it hit. (Watch a video of size comparisons in asteroids.) The asteroid is similar in size to the one that felled a forest near Tunguska, Siberia, in 1908.

Star chart showing stars with labels and location of asteroid at center.
This was the location of asteroid 2024 YR4 as on January 27, 2025. Currently it’s in the direction of the star Procyon in Canis Minor. However it’s incredibly dim at magnitude 23. Image via TheSkyLive.

What is the Torino scale?

The IAU has been using the Torino Impact Hazard Scale since 1999 to categorize asteroids that could potentially hit Earth. An object – such as 2024 YR4 – with a score of 3 puts in the yellow zone. This means the object merits attention by astronomers:

A close encounter, meriting attention by astronomers. Current calculations give a 1% or greater chance of collision capable of localized destruction. Most likely, new telescopic observations will lead to re-assignment to Level 0. Attention by public and by public officials is merited if the encounter is less than a decade away.

In fact, most new asteroids that get listed on the Torino scale have their likelihood of hitting Earth go up with more observations … until it drops to zero. That’s because the uncertain path of the asteroid is wide and more observations shrinks the path, making it look more likely, until the path shrinks enough to show that it will not cross Earth’s. It’s likely that’s what will happen with asteroid 2024 YR4 also.

In 2023, EarthSky spoke with the inventor of the Torino scale, Richard Binzel of the Massachusetts Institute of Technology. He said that we should expect more objects to make the Torino scale as our technology improves, allowing us to see smaller objects we otherwise would have missed. So, we had better get used to seeing objects on the Torino scale, at least temporarily.

How is asteroid 2024 different?

Asteroid 2024 YR4 presents a challenge to observations, however. The potential for an impact is still seven years away, but the asteroid is moving into a position where astronomers will not be able to observe it for about three years. At the moment the asteroid is magnitude 23 and will continue to dim through February until it leaves our view. So we may not get enough observations to remove the asteroid from where it currently sits on the Torino scale for a few years.

With the current data astronomers have on the asteroid, they estimate not just one possibility for impact in 2032, but seven possibilities between 2032 and 2079. The first possible impact date is December 22, 2032. Again, as more observations come in, this information will change.

Future observations

So, what if further observations of asteroid 2024 YR4 determine that it is on a collision course with Earth on December 22, 2032? To start with, the first potential impact is still years away. And we’ve already sent a mission to hit and move an asteroid as a test of our planetary defense system. That mission was the Double Asteroid Redirection Test (DART), which impacted with an asteroid’s moon named Dimorphos in 2022. And Dimorphos was much larger than asteroid 2024 YR4, at 525 feet (160 meters) across.

Bottom line: Astronomers discovered an asteroid in December that has a 1-in-83 chance of hitting Earth in 2032. The asteroid 2024 YR4 is about 150 feet (50 m) wide.

Via IAU Minor Planet Center

Via ESA

The post Asteroid 2024 YR4 has non-zero odds of hitting Earth first appeared on EarthSky.



from EarthSky https://ift.tt/VmR9yex

A super-Venus exoplanet (with a watery name)

Super-Venus exoplanet: Dark planet near its bright reddish star, with many more stars in the background.
View larger. | Artist’s concept of the exoplanet – a world orbiting a distant star – called GJ 1214 b. Previously thought to be a watery “super-Earth,” or a mini-Neptune with a hydrogen atmosphere, astronomers now say this world is more like a super-Venus, with an atmosphere rich in carbon dioxide. Image via NAOJ.
  • GJ 1214 b is a distant planet, about 48 light-years from Earth. Astronomers thought it was probably a watery and rocky world larger than Earth, or a smaller version of our solar system’s ice giant Neptune. They gave it a name meaning “large body of water.”
  • But now it seems this world might be an oversized Venus, researchers in Japan and the U.S. said this month. New results from NASA’s Webb Space Telescope suggest its atmosphere is like that of Venus, mostly carbon dioxide.
  • If so, it’s a new class of planet, unlike any seen before.

In 2009, when astronomers discovered the exoplanet known as GJ 1214 b, they thought it was likely either a super-Earth water world or a mini-Neptune. Those are two of the different kinds of exoplanets discovered so far in our home galaxy, the Milky Way. But a blanket of haze in the atmosphere of GJ 1214 b made classification difficult. And now, it appears, they were wrong.

Now, a new study suggests, GJ 1214 b is entirely new to astronomers’ understanding of the worlds inhabiting our Milky Way. Using NASA’s Webb space telescope, researchers at the National Astronomical Observatory of Japan and the University of Arizona in the U.S., said in two press releases (January 15, 2025, and January 24) that the planet is probably more like an oversized Venus, with a thick atmosphere of carbon dioxide. So it’s a super-Venus.

2025 EarthSky lunar calendar is available now. A unique and beautiful poster-sized calendar with phases of the moon for every night of the year. Get yours today!

The research teams published their peer-reviewed findings in two new papers in The Astrophysical Journal Letters, on October 16, 2024 and January 14, 2025.

GJ 1214 b, aka Enaiposha

Astronomers first found GJ 1214 b in 2009, orbiting a star 48 light-years away in the direction to our constellation Ophiuchus. Scientists thought it was most likely a super-Earth – larger and more massive than Earth – with a water-rich atmosphere and possible global ocean. It’s an interesting place, which is why, in 2023, the International Astronomical Union (IAU) included this world in a public exoplanet-naming process. That process resulted in the official name Enaiposha for GJ 1214 b. The name means “large body of water” in the Maasai language.

The IAU also acknowledged that GJ 1214 b might instead be a mini-Neptune, an ice giant with a deep hydrogen atmosphere. Or it might be a rocky planet like Earth, but with a hydrogen atmosphere. They weren’t sure!

What did we know for sure as recently as 2023? We knew that the planet orbits its star about 70 times closer than Earth orbits our sun. But, beyond that, GJ 1214 b or Enaiposha was mysterious. As Matthew Murphy, a graduate student at the University of Arizona and co-author of both papers said:

It has been the prevailing puzzle in the field for a decade.

Super-Venus exoplanet

The new work that GJ 1214 b or Enaiposha has an atmosphere dominated by carbon dioxide (CO2). So it’s something not seen before, a super-sized Venus. Lead author of the University of Arizona paper, Everett Schlawin, called it:

… a new class of planet.

Are the researchers now certain? No. They caution their findings are still tentative. Kazumasa Ohno at the National Astronomical Observatory of Japan explained:

The detected CO2 signal from the first study is tiny, and so it required careful statistical analysis to ensure that it is real. At the same time, we needed the physical and chemical insights to extract the true nature of GJ 1214 b’s atmosphere from Schlawin’s study.

Schlawin added:

It’s equivalent to Leo Tolstoy’s ‘War and Peace.’ If I gave you two copies and changed one sentence in one of the books, could you find that sentence?

Ohno’s team then used theoretical models to evaluate the most likely composition of the atmosphere. The Venus model – a carbon dioxide atmosphere – came out on top, bolstering the other findings.

Blue planet with thin wispy clouds and another tiny, distant planet and distant bright red sun.
Artist’s concept of exoplanet K2-18 b, which might have a global ocean of water beneath its deep atmosphere. Scientists thought that GJ 1214 b might be similar, but now say it’s probably more like a larger version of Venus. Image via NASA/ CSA/ ESA/ J. Olmsted (STScI); Science: N. Madhusudhan (Cambridge University).

More studies needed

So the researchers will need further study to conform the super-Venus scenario. But the results so far suggest even more diversity among exoplanets than we knew. Indeed, some, or many, are unlike any planets in our own solar system. Super-Venuses would be a fascinating addition to the exoplanet family. And this might be our first glimpse of one. Murphy said:

Although we’re not setting foot on another planet and walking around, we’re really pioneers. We’re the first humans to see what’s happening on this other planet. It’s amazing what you can do when you have a team from all over the globe.

Bottom line: Astronomers thought that exoplanet GJ 1214 b was either a watery super-Earth or a mini-Neptune. But a new study says it is more like a super-Venus exoplanet.

Source: Possible Carbon Dioxide above the Thick Aerosols of GJ 1214 b

Source: A Possible Metal-dominated Atmosphere below the Thick Aerosols of GJ 1214 b Suggested by Its JWST Panchromatic Transmission Spectrum

Via National Astronomical Observatory of Japan

Via The University of Arizona

Read more: Super-Earth may have water as steam or high clouds

Read more: Super-Earth, mini-Neptune or sub-Neptune?

The post A super-Venus exoplanet (with a watery name) first appeared on EarthSky.



from EarthSky https://ift.tt/Bas7oOE
Super-Venus exoplanet: Dark planet near its bright reddish star, with many more stars in the background.
View larger. | Artist’s concept of the exoplanet – a world orbiting a distant star – called GJ 1214 b. Previously thought to be a watery “super-Earth,” or a mini-Neptune with a hydrogen atmosphere, astronomers now say this world is more like a super-Venus, with an atmosphere rich in carbon dioxide. Image via NAOJ.
  • GJ 1214 b is a distant planet, about 48 light-years from Earth. Astronomers thought it was probably a watery and rocky world larger than Earth, or a smaller version of our solar system’s ice giant Neptune. They gave it a name meaning “large body of water.”
  • But now it seems this world might be an oversized Venus, researchers in Japan and the U.S. said this month. New results from NASA’s Webb Space Telescope suggest its atmosphere is like that of Venus, mostly carbon dioxide.
  • If so, it’s a new class of planet, unlike any seen before.

In 2009, when astronomers discovered the exoplanet known as GJ 1214 b, they thought it was likely either a super-Earth water world or a mini-Neptune. Those are two of the different kinds of exoplanets discovered so far in our home galaxy, the Milky Way. But a blanket of haze in the atmosphere of GJ 1214 b made classification difficult. And now, it appears, they were wrong.

Now, a new study suggests, GJ 1214 b is entirely new to astronomers’ understanding of the worlds inhabiting our Milky Way. Using NASA’s Webb space telescope, researchers at the National Astronomical Observatory of Japan and the University of Arizona in the U.S., said in two press releases (January 15, 2025, and January 24) that the planet is probably more like an oversized Venus, with a thick atmosphere of carbon dioxide. So it’s a super-Venus.

2025 EarthSky lunar calendar is available now. A unique and beautiful poster-sized calendar with phases of the moon for every night of the year. Get yours today!

The research teams published their peer-reviewed findings in two new papers in The Astrophysical Journal Letters, on October 16, 2024 and January 14, 2025.

GJ 1214 b, aka Enaiposha

Astronomers first found GJ 1214 b in 2009, orbiting a star 48 light-years away in the direction to our constellation Ophiuchus. Scientists thought it was most likely a super-Earth – larger and more massive than Earth – with a water-rich atmosphere and possible global ocean. It’s an interesting place, which is why, in 2023, the International Astronomical Union (IAU) included this world in a public exoplanet-naming process. That process resulted in the official name Enaiposha for GJ 1214 b. The name means “large body of water” in the Maasai language.

The IAU also acknowledged that GJ 1214 b might instead be a mini-Neptune, an ice giant with a deep hydrogen atmosphere. Or it might be a rocky planet like Earth, but with a hydrogen atmosphere. They weren’t sure!

What did we know for sure as recently as 2023? We knew that the planet orbits its star about 70 times closer than Earth orbits our sun. But, beyond that, GJ 1214 b or Enaiposha was mysterious. As Matthew Murphy, a graduate student at the University of Arizona and co-author of both papers said:

It has been the prevailing puzzle in the field for a decade.

Super-Venus exoplanet

The new work that GJ 1214 b or Enaiposha has an atmosphere dominated by carbon dioxide (CO2). So it’s something not seen before, a super-sized Venus. Lead author of the University of Arizona paper, Everett Schlawin, called it:

… a new class of planet.

Are the researchers now certain? No. They caution their findings are still tentative. Kazumasa Ohno at the National Astronomical Observatory of Japan explained:

The detected CO2 signal from the first study is tiny, and so it required careful statistical analysis to ensure that it is real. At the same time, we needed the physical and chemical insights to extract the true nature of GJ 1214 b’s atmosphere from Schlawin’s study.

Schlawin added:

It’s equivalent to Leo Tolstoy’s ‘War and Peace.’ If I gave you two copies and changed one sentence in one of the books, could you find that sentence?

Ohno’s team then used theoretical models to evaluate the most likely composition of the atmosphere. The Venus model – a carbon dioxide atmosphere – came out on top, bolstering the other findings.

Blue planet with thin wispy clouds and another tiny, distant planet and distant bright red sun.
Artist’s concept of exoplanet K2-18 b, which might have a global ocean of water beneath its deep atmosphere. Scientists thought that GJ 1214 b might be similar, but now say it’s probably more like a larger version of Venus. Image via NASA/ CSA/ ESA/ J. Olmsted (STScI); Science: N. Madhusudhan (Cambridge University).

More studies needed

So the researchers will need further study to conform the super-Venus scenario. But the results so far suggest even more diversity among exoplanets than we knew. Indeed, some, or many, are unlike any planets in our own solar system. Super-Venuses would be a fascinating addition to the exoplanet family. And this might be our first glimpse of one. Murphy said:

Although we’re not setting foot on another planet and walking around, we’re really pioneers. We’re the first humans to see what’s happening on this other planet. It’s amazing what you can do when you have a team from all over the globe.

Bottom line: Astronomers thought that exoplanet GJ 1214 b was either a watery super-Earth or a mini-Neptune. But a new study says it is more like a super-Venus exoplanet.

Source: Possible Carbon Dioxide above the Thick Aerosols of GJ 1214 b

Source: A Possible Metal-dominated Atmosphere below the Thick Aerosols of GJ 1214 b Suggested by Its JWST Panchromatic Transmission Spectrum

Via National Astronomical Observatory of Japan

Via The University of Arizona

Read more: Super-Earth may have water as steam or high clouds

Read more: Super-Earth, mini-Neptune or sub-Neptune?

The post A super-Venus exoplanet (with a watery name) first appeared on EarthSky.



from EarthSky https://ift.tt/Bas7oOE

Hummingbirds snooze when energy is low

Hummingbirds are tiny birds. Yet – powered by the nectar of flowers – some species can migrate more than 5,600 miles (9,000 km) a year. But as climate and land use are changing, so the locations of wildflowers are changing. And a new study of hummingbirds in New Mexico shows how some hummingbirds are going into short hibernation periods overnight to conserve energy for the next day’s journey. It’s not ordinary sleeping. It’s a deeper form of sleeping, which the scientists call torpor. The scientists announced their results on January 15, 2025. They said said they’ve found specific fat levels and fat reserves that some migratory hummingbirds need to go into hibernation and then resume their journeys in the morning. And they said:

Hummingbirds apparently adjust their use of torpor to wake up in the morning with a minimum fat reserve that allows for survival on a day-to-day basis in an uncertain environment.

The scientists, from the University of New Mexico, published their study in the peer-reviewed journal Proceedings of the Royal Society B on January 15, 2025.

The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Get yours today!

What are hummingbirds’ migrations like?

Hummingbirds are fascinating creatures. They might be small but they’re also resilient. Not only do they make long migrations, but also these tiny birds use a lot of energy when they move. Their wings can beat at speeds of 70 to 200 times per second. So they need an almost constant source of food.

During their travels, hummingbirds feed largely on nectar, which they drink from flowers and convert into fat. However, sometimes these birds encounter changes in land use. For example, one year the land may be fallow and unplanted. Or there may be fewer plants that produce nectar. Climate change is also making the land drier; thus, there are fewer wildflowers. So the distribution of wildflowers along migratory routes is often unpredictable.

Hummingbirds: Tiny bird with its wings open. It has green, white and black feathers for the body and wings, and blue feathers for the head.
Some species of hummingbirds undertake long migrations. Sometimes, they enter a torpor state to save energy and survive in uncertain environments. Image via Zdenek Machácek/ Unsplash.

What is torpor?

In any case, the migratory routes of these animals are becoming more and more unpredictable. To protect themselves from these challenges, hummingbirds resort to a kind of nocturnal hibernation called torpor. But instead of lasting days or months as in other animals, it lasts only a few hours.

During torpor, body temperature drops and metabolic rate slows to conserve as much energy as possible. These little creatures resort to torpor at night and wake up in the morning with a minimal reserve of fat.

In his research, Shayne R. Halter, a Ph.D. candidate in the Department of Biology at the University of New Mexico, observed two species of hummingbirds during their annual migratory journeys as they headed south in the fall, crossing through New Mexico. One is the calliope hummingbird (Selasphorus calliope) and the other is the rufous hummingbird (Selasphorus rufus).

Halter, along with Blair Wolf, a professor of biology at the University of New Mexico, and co-author Carlos Martinez del Rio, professor emeritus in the Department of Zoology and Physiology at the University of Wyoming, investigated how hummingbirds make use of torpor and maintain their fat levels.

Little bird with short green feathers for its body. It has longer feathers for the tail. These feathers look black and orange. It has a long beak and its eyes are closed.
Torpor is a sort of hibernation that lasts only hours instead of days or months. Image via Bernal Fallas/ Unsplash.

How does torpor work?

Halter found that hummingbirds enter torpor if their evening body fat falls below a specific threshold, where maintaining a high body temperature would cause their minimum morning fat reserves to fall below a critical value. In other words, hummingbirds need a minimum fat reserve in the morning to get going until they can find their next food source. Halter said:

In my research, I use a combination of body fat and overnight metabolic measurements to determine whether hummingbirds are low on energy and how they compensate with torpor. The data I collected allows me to predict if and for how long these birds will enter torpor and how much energy reserve they require in the morning to sustain them until they can find their next meal.

He also explained what the specific limits of fat are for the two species of migratory hummingbirds he studied:

In our research on rufous and calliope hummingbirds, we found that torpor occurred when fat levels fell below 500 milligrams, and we found minimum morning fat reserves to be approximately 180 milligrams. Birds will only use torpor if needed and will adjust its duration to meet the minimum morning fat reserve.

Green bird sitting on a green stem. It has a long beak and its eyes are closing.
These little creatures enter a torpor state to save energy when they reach a low level of fat in the evening. Image via Caterina Sanders/ Unsplash.

Torpor can make hummingbirds vulnerable

Halter noted that yearly migrations are challenging for hummingbirds and often result in high mortality. The increasingly hot and dry conditions in the arid Southwest are already affecting when and where nectar is available. Furthermore, changes in land use are replacing native plants with invasive and cultivated species that do not provide nectar. According to Halter:

During torpor, hummingbirds are unaware of their surroundings, making them more vulnerable to predation and other risks. For this reason, torpor should only be used when needed.

This research, by offering a model that predicts torpor frequencies, durations and fat reserves in migratory hummingbirds, will help assess ecological health, establish their energy thresholds and limits, and guide the development of conservation strategies.

Green, black and white bird sitting on a red feeder.
Hummingbirds face many challenges. Sometimes, there are not flowers they can feed on while migrating. By undestanding when and why they enter the torpor state, we can implement strategies to help them undertake safe travels. Image via Joshua J. Cotten/ Unsplash.

Bottom line: Some species of hummingbirds undertake long migrations and face uncertain situations. To save energy, they enter a state of hibernation called torpor. Read more about it here.

Source: The hummingbird’s adipostat: can a simple rule explain torpor frequency and duration in hummingbirds?

Via The University of New Mexico

Read more: Hummingbirds, tiny and colorful: Lifeform of the week

Read more: Giant hummingbirds with backpacks help discover a species

The post Hummingbirds snooze when energy is low first appeared on EarthSky.



from EarthSky https://ift.tt/AnmTfQb

Hummingbirds are tiny birds. Yet – powered by the nectar of flowers – some species can migrate more than 5,600 miles (9,000 km) a year. But as climate and land use are changing, so the locations of wildflowers are changing. And a new study of hummingbirds in New Mexico shows how some hummingbirds are going into short hibernation periods overnight to conserve energy for the next day’s journey. It’s not ordinary sleeping. It’s a deeper form of sleeping, which the scientists call torpor. The scientists announced their results on January 15, 2025. They said said they’ve found specific fat levels and fat reserves that some migratory hummingbirds need to go into hibernation and then resume their journeys in the morning. And they said:

Hummingbirds apparently adjust their use of torpor to wake up in the morning with a minimum fat reserve that allows for survival on a day-to-day basis in an uncertain environment.

The scientists, from the University of New Mexico, published their study in the peer-reviewed journal Proceedings of the Royal Society B on January 15, 2025.

The 2025 EarthSky Lunar Calendar is now available! A unique and beautiful poster-sized calendar. Get yours today!

What are hummingbirds’ migrations like?

Hummingbirds are fascinating creatures. They might be small but they’re also resilient. Not only do they make long migrations, but also these tiny birds use a lot of energy when they move. Their wings can beat at speeds of 70 to 200 times per second. So they need an almost constant source of food.

During their travels, hummingbirds feed largely on nectar, which they drink from flowers and convert into fat. However, sometimes these birds encounter changes in land use. For example, one year the land may be fallow and unplanted. Or there may be fewer plants that produce nectar. Climate change is also making the land drier; thus, there are fewer wildflowers. So the distribution of wildflowers along migratory routes is often unpredictable.

Hummingbirds: Tiny bird with its wings open. It has green, white and black feathers for the body and wings, and blue feathers for the head.
Some species of hummingbirds undertake long migrations. Sometimes, they enter a torpor state to save energy and survive in uncertain environments. Image via Zdenek Machácek/ Unsplash.

What is torpor?

In any case, the migratory routes of these animals are becoming more and more unpredictable. To protect themselves from these challenges, hummingbirds resort to a kind of nocturnal hibernation called torpor. But instead of lasting days or months as in other animals, it lasts only a few hours.

During torpor, body temperature drops and metabolic rate slows to conserve as much energy as possible. These little creatures resort to torpor at night and wake up in the morning with a minimal reserve of fat.

In his research, Shayne R. Halter, a Ph.D. candidate in the Department of Biology at the University of New Mexico, observed two species of hummingbirds during their annual migratory journeys as they headed south in the fall, crossing through New Mexico. One is the calliope hummingbird (Selasphorus calliope) and the other is the rufous hummingbird (Selasphorus rufus).

Halter, along with Blair Wolf, a professor of biology at the University of New Mexico, and co-author Carlos Martinez del Rio, professor emeritus in the Department of Zoology and Physiology at the University of Wyoming, investigated how hummingbirds make use of torpor and maintain their fat levels.

Little bird with short green feathers for its body. It has longer feathers for the tail. These feathers look black and orange. It has a long beak and its eyes are closed.
Torpor is a sort of hibernation that lasts only hours instead of days or months. Image via Bernal Fallas/ Unsplash.

How does torpor work?

Halter found that hummingbirds enter torpor if their evening body fat falls below a specific threshold, where maintaining a high body temperature would cause their minimum morning fat reserves to fall below a critical value. In other words, hummingbirds need a minimum fat reserve in the morning to get going until they can find their next food source. Halter said:

In my research, I use a combination of body fat and overnight metabolic measurements to determine whether hummingbirds are low on energy and how they compensate with torpor. The data I collected allows me to predict if and for how long these birds will enter torpor and how much energy reserve they require in the morning to sustain them until they can find their next meal.

He also explained what the specific limits of fat are for the two species of migratory hummingbirds he studied:

In our research on rufous and calliope hummingbirds, we found that torpor occurred when fat levels fell below 500 milligrams, and we found minimum morning fat reserves to be approximately 180 milligrams. Birds will only use torpor if needed and will adjust its duration to meet the minimum morning fat reserve.

Green bird sitting on a green stem. It has a long beak and its eyes are closing.
These little creatures enter a torpor state to save energy when they reach a low level of fat in the evening. Image via Caterina Sanders/ Unsplash.

Torpor can make hummingbirds vulnerable

Halter noted that yearly migrations are challenging for hummingbirds and often result in high mortality. The increasingly hot and dry conditions in the arid Southwest are already affecting when and where nectar is available. Furthermore, changes in land use are replacing native plants with invasive and cultivated species that do not provide nectar. According to Halter:

During torpor, hummingbirds are unaware of their surroundings, making them more vulnerable to predation and other risks. For this reason, torpor should only be used when needed.

This research, by offering a model that predicts torpor frequencies, durations and fat reserves in migratory hummingbirds, will help assess ecological health, establish their energy thresholds and limits, and guide the development of conservation strategies.

Green, black and white bird sitting on a red feeder.
Hummingbirds face many challenges. Sometimes, there are not flowers they can feed on while migrating. By undestanding when and why they enter the torpor state, we can implement strategies to help them undertake safe travels. Image via Joshua J. Cotten/ Unsplash.

Bottom line: Some species of hummingbirds undertake long migrations and face uncertain situations. To save energy, they enter a state of hibernation called torpor. Read more about it here.

Source: The hummingbird’s adipostat: can a simple rule explain torpor frequency and duration in hummingbirds?

Via The University of New Mexico

Read more: Hummingbirds, tiny and colorful: Lifeform of the week

Read more: Giant hummingbirds with backpacks help discover a species

The post Hummingbirds snooze when energy is low first appeared on EarthSky.



from EarthSky https://ift.tt/AnmTfQb

adds 2