Anglerfish are our mysterious, deep-sea lifeform of the week

Are you afraid of the dark? When it comes to anglerfish, you should fear the light. They live in the depths of the ocean and use a biological lantern to attract their prey. The female is the dominant fish, and there are many more unusual facts about these mysterious and fascinating creatures.

Beauty lies within

Normally, when talking about fish, one thinks of small, colorful animals. Well, this fish is the complete opposite of that. The anglerfish has a disproportionately large head with jaws full of teeth, in some cases very long and sharp. It is a medium-sized fish, about 12 inches (30 cm) long, but the largest anglerfish can measure 4 feet (1.2 m).

An anglerfish is not a pretty fish, but who cares? It is an impressive fish that adapts to the harsh conditions of the deep ocean. Not to mention the unique way it hunts; it uses the lantern on its head! Someone had a brilliant idea …

Anglerfish have a big head and jaws full of long, sharp teeth. Image via Eddie Widder/ NOAA.

Few creatures are as resilient as anglerfish

There are more that 200 species of anglerfish. They are found in two types of water. They live in the water found above the continental shelf, which is no more than 650 feet or 200 meters deep. Or in the abyssal plains, which are located at an ocean depth between 2.5 and 3.7 miles (4 and 6 km) deep.

If there’s barely any light at 650 feet, imagine the level of darkness, the cold and the high pressure encountered by these fish inhabiting the ocean floor.

Anglerfish have a lifespan of 25 years. Isn’t it impressive how some species manage to survive in such ruthless environments?

Anglerfish inhabit cold, dark areas of the deep sea. Image via Masaki Miya et al./ Wikipedia (CC BY 2.0).

Anglerfish have an anatomy built for survival

The anglerfish that inhabit the depths of the ocean do not have it easy, since they are subjected to very harsh conditions. Plus, food is scarce and difficult to find. So, to make the most of every opportunity, they have developed expandable jaws and stomach.

Their jaws can extend, allowing them to swallow large prey. In addition, the teeth of anglerfish are curved toward the inside of the oral cavity and can move. So, once the prey enters, it cannot escape.

On the other hand, their body is very flexible. They can eat prey up to twice their own size.

Anglerfish preferred prey is crustaceans, snails and small fish, but since the anglerfish can expand its size, it also eats large fish and even octopuses or squid.

Anglerfish have developed an expanding jaw and stomach. They can eat prey up to twice their own size. Image via NOAA.

A brilliant trap

No matter how many survival skills anglerfish have, nothing can be seen in the dark. Therefore, evolution had a brilliant idea for our favorite little monster fish.

Basically, there’s a lantern on the head of anglerfish, located at the end of a type of fishing rod. The part that shines is at the end, falling in front of the eyes and mouth. Naturally, the fish that inhabit these dark areas are attracted to light. And as luck would have it, anglerfish can see better than they do.

Anglerfish may swim aimlessly with their lantern shining, waiting for something to take the bait, or they may wait buried in the sand.

This bioluminescent lantern’s light is generated through a chemical reaction. It is not genetically passed on from the parents; anglerfish emit light thanks to bacteria capable of generating it. These microorganisms are acquired from the environment, in what is called symbiosis. So the bacteria receive nutrients from the fish and, in return, the fish gains an organ that lights up and allows it to attract prey … and mates.

Anglerfish use their lantern to see better, hunt and find a mate. Image via Masaki Miya et al./ Wikipedia (CC BY 2.0).

Female power

In the case of anglerfish, there is sexual dimorphism. This means that one gender is very different than the other. One obvious difference is female anglerfish are much larger than the males.

Also, only the females have a lantern. Males do not need this shiny trap, nor large bodies, nor long, sharp teeth. However, males possess an impeccable sense of smell that they use to sniff out their future partner in the pitch-black expanse of the deep sea.

If it is difficult to find food at this depth, it is even harder to find a girlfriend. Therefore, in many species, once the male finds a female, the male never separates himself from her.

The male bites the female’s belly, releasing an enzyme that dissolves the skin under the bite and fuses his mouth with her body. In this way, he will draw sustenance from her for the rest of her life. The males become parasites of the females. Some females can be parasitized by up to six males.

Only females have the lantern. They are the dominant fish. In many cases, males become parasites of the females. Image via Eddie Widder/ HBOI/ NOAA.

Baby anglerfish develop on their own

The good thing is that, in return, the female will have a supply of sperm ready whenever she is ready to mate. Fertilization is external, so the male and female release sperm and ovules at the same time. The adults do not monitor the fertilized eggs; they develop independently.

In some species, once reproduction is over, males leave the females.

Males are small, and don’t have a lantern. They are dependent on the females. Image via Masaki Miya et al./ Wikipedia (CC BY 2.0).

Bottom line: Are you afraid of the dark? Well, anglerfish are not! That’s because they have a lantern on their head that they use to attract prey in the dark deep sea. Also, they have a huge mouth full of long, sharp teeth. As you can see, it’s truly an amazing monster fish!

Ocean sunfish are odd, gentle giants: Lifeform of the week

Seahorses are tiny, ravenous creatures: Lifeform of the week

The post Anglerfish are our mysterious, deep-sea lifeform of the week first appeared on EarthSky.

from EarthSky https://ift.tt/igv7pV4

Are you afraid of the dark? When it comes to anglerfish, you should fear the light. They live in the depths of the ocean and use a biological lantern to attract their prey. The female is the dominant fish, and there are many more unusual facts about these mysterious and fascinating creatures.

Beauty lies within

Normally, when talking about fish, one thinks of small, colorful animals. Well, this fish is the complete opposite of that. The anglerfish has a disproportionately large head with jaws full of teeth, in some cases very long and sharp. It is a medium-sized fish, about 12 inches (30 cm) long, but the largest anglerfish can measure 4 feet (1.2 m).

An anglerfish is not a pretty fish, but who cares? It is an impressive fish that adapts to the harsh conditions of the deep ocean. Not to mention the unique way it hunts; it uses the lantern on its head! Someone had a brilliant idea …

Anglerfish have a big head and jaws full of long, sharp teeth. Image via Eddie Widder/ NOAA.

Few creatures are as resilient as anglerfish

There are more that 200 species of anglerfish. They are found in two types of water. They live in the water found above the continental shelf, which is no more than 650 feet or 200 meters deep. Or in the abyssal plains, which are located at an ocean depth between 2.5 and 3.7 miles (4 and 6 km) deep.

If there’s barely any light at 650 feet, imagine the level of darkness, the cold and the high pressure encountered by these fish inhabiting the ocean floor.

Anglerfish have a lifespan of 25 years. Isn’t it impressive how some species manage to survive in such ruthless environments?

Anglerfish inhabit cold, dark areas of the deep sea. Image via Masaki Miya et al./ Wikipedia (CC BY 2.0).

Anglerfish have an anatomy built for survival

The anglerfish that inhabit the depths of the ocean do not have it easy, since they are subjected to very harsh conditions. Plus, food is scarce and difficult to find. So, to make the most of every opportunity, they have developed expandable jaws and stomach.

Their jaws can extend, allowing them to swallow large prey. In addition, the teeth of anglerfish are curved toward the inside of the oral cavity and can move. So, once the prey enters, it cannot escape.

On the other hand, their body is very flexible. They can eat prey up to twice their own size.

Anglerfish preferred prey is crustaceans, snails and small fish, but since the anglerfish can expand its size, it also eats large fish and even octopuses or squid.

Anglerfish have developed an expanding jaw and stomach. They can eat prey up to twice their own size. Image via NOAA.

A brilliant trap

No matter how many survival skills anglerfish have, nothing can be seen in the dark. Therefore, evolution had a brilliant idea for our favorite little monster fish.

Basically, there’s a lantern on the head of anglerfish, located at the end of a type of fishing rod. The part that shines is at the end, falling in front of the eyes and mouth. Naturally, the fish that inhabit these dark areas are attracted to light. And as luck would have it, anglerfish can see better than they do.

Anglerfish may swim aimlessly with their lantern shining, waiting for something to take the bait, or they may wait buried in the sand.

This bioluminescent lantern’s light is generated through a chemical reaction. It is not genetically passed on from the parents; anglerfish emit light thanks to bacteria capable of generating it. These microorganisms are acquired from the environment, in what is called symbiosis. So the bacteria receive nutrients from the fish and, in return, the fish gains an organ that lights up and allows it to attract prey … and mates.

Anglerfish use their lantern to see better, hunt and find a mate. Image via Masaki Miya et al./ Wikipedia (CC BY 2.0).

Female power

In the case of anglerfish, there is sexual dimorphism. This means that one gender is very different than the other. One obvious difference is female anglerfish are much larger than the males.

Also, only the females have a lantern. Males do not need this shiny trap, nor large bodies, nor long, sharp teeth. However, males possess an impeccable sense of smell that they use to sniff out their future partner in the pitch-black expanse of the deep sea.

If it is difficult to find food at this depth, it is even harder to find a girlfriend. Therefore, in many species, once the male finds a female, the male never separates himself from her.

The male bites the female’s belly, releasing an enzyme that dissolves the skin under the bite and fuses his mouth with her body. In this way, he will draw sustenance from her for the rest of her life. The males become parasites of the females. Some females can be parasitized by up to six males.

Only females have the lantern. They are the dominant fish. In many cases, males become parasites of the females. Image via Eddie Widder/ HBOI/ NOAA.

Baby anglerfish develop on their own

The good thing is that, in return, the female will have a supply of sperm ready whenever she is ready to mate. Fertilization is external, so the male and female release sperm and ovules at the same time. The adults do not monitor the fertilized eggs; they develop independently.

In some species, once reproduction is over, males leave the females.

Males are small, and don’t have a lantern. They are dependent on the females. Image via Masaki Miya et al./ Wikipedia (CC BY 2.0).

Bottom line: Are you afraid of the dark? Well, anglerfish are not! That’s because they have a lantern on their head that they use to attract prey in the dark deep sea. Also, they have a huge mouth full of long, sharp teeth. As you can see, it’s truly an amazing monster fish!

Ocean sunfish are odd, gentle giants: Lifeform of the week

Seahorses are tiny, ravenous creatures: Lifeform of the week

The post Anglerfish are our mysterious, deep-sea lifeform of the week first appeared on EarthSky.

from EarthSky https://ift.tt/igv7pV4

LIVE on Monday: Super Blue Moon

The Super Blue Moon is coming! Join the EarthSky team LIVE beginning at 12:15 p.m. (17:15 UTC) on Monday, August 19, 2024, for all you need to know.

The August 2024 full moon will arrive this Monday, August 19. For everyone around the globe, the bright round moon will rise in the east just after sunset Monday evening. This full moon will hang in the sky near Saturn. Plus, it’s the 1st of four full supermoons in a row. And on top of that, it’s a Blue Moon. What does it all mean? Join EarthSky’s Dave Adalian, Deborah Byrd, Marcy Curran and John Goss as we explore the Super Blue Moon! We’ll be talking LIVE beginning at 12:15 p.m. (17:15 UTC) on Monday, August 19. Join us!

You’ll learn some Blue Moon folklore, all about supermoons, and about some upcoming events for the moon … plus what to watch for on the moon with binoculars.

The August full moon happens at 18:26 UTC (1:26 p.m. CDT) on August 19. For everyone around the globe, the moon will rise – round and nearly or entirely full – in the east just after sunset that evening. Plus, the August 19 full moon will lie near Saturn. It’s the 1st of 4 full supermoons in a row. And it’s a Blue Moon. Chart via EarthSky.

Bottom line: Join EarthSky team members LIVE beginning at 12:15 p.m. (17:15 UTC) on Monday, August 19, 2024 … to talk about Monday night’s Super Blue Moon.

What’s a Blue Moon?

What’s a supermoon?

The post LIVE on Monday: Super Blue Moon first appeared on EarthSky.

from EarthSky https://ift.tt/o70BJw1

The Super Blue Moon is coming! Join the EarthSky team LIVE beginning at 12:15 p.m. (17:15 UTC) on Monday, August 19, 2024, for all you need to know.

The August 2024 full moon will arrive this Monday, August 19. For everyone around the globe, the bright round moon will rise in the east just after sunset Monday evening. This full moon will hang in the sky near Saturn. Plus, it’s the 1st of four full supermoons in a row. And on top of that, it’s a Blue Moon. What does it all mean? Join EarthSky’s Dave Adalian, Deborah Byrd, Marcy Curran and John Goss as we explore the Super Blue Moon! We’ll be talking LIVE beginning at 12:15 p.m. (17:15 UTC) on Monday, August 19. Join us!

You’ll learn some Blue Moon folklore, all about supermoons, and about some upcoming events for the moon … plus what to watch for on the moon with binoculars.

The August full moon happens at 18:26 UTC (1:26 p.m. CDT) on August 19. For everyone around the globe, the moon will rise – round and nearly or entirely full – in the east just after sunset that evening. Plus, the August 19 full moon will lie near Saturn. It’s the 1st of 4 full supermoons in a row. And it’s a Blue Moon. Chart via EarthSky.

Bottom line: Join EarthSky team members LIVE beginning at 12:15 p.m. (17:15 UTC) on Monday, August 19, 2024 … to talk about Monday night’s Super Blue Moon.

What’s a Blue Moon?

What’s a supermoon?

The post LIVE on Monday: Super Blue Moon first appeared on EarthSky.

from EarthSky https://ift.tt/o70BJw1

JUICE mission to Jupiter to sweep past moon and Earth this week

View larger. | Here’s a timeline and the path the JUICE spacecraft will take in the 2nd part of its double flyby – of the moon and Earth – for a gravity assist. JUICE will fly past the moon on August 19, 2024. This diagram shows the Earth part of the flyby on August 20. The ultimate goal of the JUICE mission is to reach Jupiter in 2031. Image via ESA.

Juice mission to make flyby of the moon and Earth

On August 19 and 20, 2024, the JUICE spacecraft will sweep near the moon and Earth system, coming as close as it can to both worlds before slingshotting out into space again with an altered speed and direction. These gravity assists will help propel the craft on its way to Jupiter’s icy moons. It’ll be the world’s first flyby gravity assist using both Earth and its moon and the first-ever double gravity assist. The craft will encounter the moon first and then Earth 36 hours later. The result will be a single flyby maneuver.

JUICE launched on its journey to Jupiter’s moons in 2023. This will be its first gravity assist, followed by one using Venus in 2025, and two more using Earth in 2026 and 2029, before arriving in Jupiter’s vicinity in 2031.

The flybys of the moon and Earth are technically braking maneuvers. They’ll line JUICE up to reach Venus, where the gravity assist will work to speed up the spacecraft, or give it the juice, if you will. The spacecraft will come within 430 miles (700 km) of the moon and about 4,200 miles (6,800 km) of Earth during the flybys. Ignacio Tanco of ESA said:

It’s like passing through a very narrow corridor, very, very quickly: pushing the accelerator to the maximum when the margin at the side of the road is just millimeters.

Science and observations

JUICE’s 10 instruments will be active as the spacecraft makes its flybys. It’s an important opportunity to test the equipment before it reaches Jupiter. In particular, the Radar for Icy Moon Exploration (RIME) instrument will get eight minutes of solo observation as it passes the moon. The instrument is sensitive to other electronic noise.

When the spacecraft passes overhead, people in Southeast Asia and the Pacific have an opportunity to see it pass. Try using binoculars or a telescope, and get more info on its path here. Plus, while you’re looking up at JUICE, it will be looking down at us. Expect to see images of Earth from JUICE soon after the flyby!

Graphics for the moon and Earth flyby

The JUICE mission will first fly by the moon on August 19, 2024. It is the first step in a world’s first flyby of both the moon and Earth. Image via ESA.

On August 20, 2024, the JUICE mission will fly by Earth. It will be coming off a flyby of the moon. These gravity assists will help JUICE eventually reach Jupiter. Image via ESA.

JUICE mission launched on April 14, 2023

ESA‘s JUICE mission launched on April 14, 2023, after a one-day delay due to lightning at ESA’s spaceport in French Guiana. The spacecraft lifted off successfully into cloudy skies, beginning a multi-year mission to Jupiter and its icy moons.

As often happens with missions to the outer solar system, the spacecraft will take a circuitous route to Jupiter, making multiple sweeps past the Earth, moon and Venus. Then, in 2031, it’ll arrive at the giant planet. At that time it’ll perform 35 flybys of the Galilean moons Ganymede, Callisto and Europa, before going into orbit around the largest moon, Ganymede.

JUICE stands for JUpiter Icy Moons Explorer.

View larger. | This is JUICE’s journey to Jupiter. It will become a reality (fingers crossed) in July 2031, when JUICE is scheduled to arrive at Jupiter. It’s impressive, especially considering the spacecraft will still be soaring around Earth in 2029! Only when it has completed its 2nd flyby of our home planet will JUICE make a quick 2-year hop to Jupiter. There, it’ll complete 35 flybys of the giant planet’s 3 largest moons: Ganymede, Callisto, and Europa (pictured 1st, 5th, and 4th from the left, respectively). Image via ESA.

Jammed antenna

The JUICE mission’s primary antenna jammed soon after launch. But after three weeks of troubleshooting, engineers finally managed to fix the antenna. As the spacecraft traveled through deep space, JUICE mission control tried using thrusters to shake the antenna. Then they tried warming the jammed components in the sun’s rays. Finally, the team fired a mechanical device called an actuator. And that’s what made the antenna break free from its stuck position on May 12, 2023. This RIME antenna, which stands for Radar for Icy Moons Exploration, will be used to study the structure of Jupiter’s icy moons down to a depth of 5.5 miles (9 km) when it finally reaches the gas giant in July 2031.

? Shocking RIME update ?

The RIME antenna on @ESA_JUICE is free!!!

This Juice Monitoring Camera GIF shows the moments after the Flight Control Team at ESA #MissionControl fired the remaining 'actuator' on the jammed bracket.

More info: https://t.co/QzZdleTdgt pic.twitter.com/T96RIg3hKA

— ESA Operations (@esaoperations) May 12, 2023

JUICE mission goals

ESA said its goals for JUICE are to:

… make detailed observations of the giant gas planet and its three large ocean-bearing moons – Ganymede, Callisto and Europa – with a suite of remote sensing, geophysical and in situ instruments.

And, ESA said, the mission will characterize these moons as both planetary objects and possible habitats.

ESA hopes that a wider study of the Jupiter system can be used as an archetype for gas giant planets and their moons across our Milky Way galaxy.

Liftoff for humankind’s next bold mission to the outer Solar System – #ESAJuice onboard @Ariane5 #VA260 ? ?#DestinationJupiter #ExploreFarther https://t.co/nuYjsCR6Ar

— ESA's Juice mission (@ESA_JUICE) April 14, 2023

Why JUICE will study Europa

JUICE will arrive at Jupiter in 2031. One of the moons it will observe is perhaps the most fascinating of the Jovian moons to Earthly scientists: Europa. This moon is thought to have an ocean of liquid water under its icy crust (also made of water ice). And JUICE is designed to look for the sort of chemistry on Europa that is essential to life on Earth, for example organic molecules, or molecules containing carbon that are key to life on Earth.

JUICE also aims to understand the formation of Europa’s surface features and the composition of any non-water-ice material.

Why JUICE will study Ganymede

After a series of flybys of Jupiter and three of its large, icy moons, JUICE will eventually settle into an orbit around the largest moon, Ganymede. JUICE will orbit Ganymede down to 125 miles (200 km) for about three years. It’ll end its mission with an impact on the moon’s surface.

While at Ganymede, JUICE has many science objectives. They include:

• Characterization of the ocean layers and detection of possible subsurface water reservoirs.
• Topographical, geological and compositional mapping of the surface.
• Study of the physical properties of the icy crust.
• Characterization of the internal mass distribution, dynamics and evolution of the interior.
• Investigation of the exosphere.
• Study of Ganymede’s intrinsic magnetic field and its interactions with the Jovian magnetosphere.

Having a better understanding of this wet, cold world will also help us understand possible distant worlds around other suns, scientists say.

JUICE mocktails

Earlier this year, ESA had a little fun with the acronym JUICE, by holding a space juice contest. Check out these beautiful mocktails, and find the recipes here.

Having a little fun with the JUICE mission, these were the winners of ESA’s space juice contest. The mocktails included some made by 7 and 11-year-olds. Image via ESA.

JUICE art, from kids

ESA also invited kids from around the world to create JUICE-inspired artwork. Read more about the contest here. The winning entry – submitted by 8-year-old Yaryna from Ukraine – is going to space! It’s painted on the Ariane 5 rocket which will launch JUICE.

Did you spot the beautiful artwork on the nose of the #Ariane5 fairing? Children from all over the world were invited to create a piece of art inspired by #ESAJuice and the winning design by ten-year-old Yaryna can be seen here. https://t.co/3wj377p0md pic.twitter.com/i5c7aGbTmw

— ESA's Juice mission (@ESA_JUICE) April 12, 2023

Bottom line: The JUICE mission will perform the world’s 1st-ever double gravity assist – a flyby of the moon and Earth – on August 19 and 20, 2024.

Read more: Icy moons’ puzzling features may be due to salty ice

The post JUICE mission to Jupiter to sweep past moon and Earth this week first appeared on EarthSky.

from EarthSky https://ift.tt/OIbgu5h

View larger. | Here’s a timeline and the path the JUICE spacecraft will take in the 2nd part of its double flyby – of the moon and Earth – for a gravity assist. JUICE will fly past the moon on August 19, 2024. This diagram shows the Earth part of the flyby on August 20. The ultimate goal of the JUICE mission is to reach Jupiter in 2031. Image via ESA.

Juice mission to make flyby of the moon and Earth

On August 19 and 20, 2024, the JUICE spacecraft will sweep near the moon and Earth system, coming as close as it can to both worlds before slingshotting out into space again with an altered speed and direction. These gravity assists will help propel the craft on its way to Jupiter’s icy moons. It’ll be the world’s first flyby gravity assist using both Earth and its moon and the first-ever double gravity assist. The craft will encounter the moon first and then Earth 36 hours later. The result will be a single flyby maneuver.

JUICE launched on its journey to Jupiter’s moons in 2023. This will be its first gravity assist, followed by one using Venus in 2025, and two more using Earth in 2026 and 2029, before arriving in Jupiter’s vicinity in 2031.

The flybys of the moon and Earth are technically braking maneuvers. They’ll line JUICE up to reach Venus, where the gravity assist will work to speed up the spacecraft, or give it the juice, if you will. The spacecraft will come within 430 miles (700 km) of the moon and about 4,200 miles (6,800 km) of Earth during the flybys. Ignacio Tanco of ESA said:

It’s like passing through a very narrow corridor, very, very quickly: pushing the accelerator to the maximum when the margin at the side of the road is just millimeters.

Science and observations

JUICE’s 10 instruments will be active as the spacecraft makes its flybys. It’s an important opportunity to test the equipment before it reaches Jupiter. In particular, the Radar for Icy Moon Exploration (RIME) instrument will get eight minutes of solo observation as it passes the moon. The instrument is sensitive to other electronic noise.

When the spacecraft passes overhead, people in Southeast Asia and the Pacific have an opportunity to see it pass. Try using binoculars or a telescope, and get more info on its path here. Plus, while you’re looking up at JUICE, it will be looking down at us. Expect to see images of Earth from JUICE soon after the flyby!

Graphics for the moon and Earth flyby

The JUICE mission will first fly by the moon on August 19, 2024. It is the first step in a world’s first flyby of both the moon and Earth. Image via ESA.

On August 20, 2024, the JUICE mission will fly by Earth. It will be coming off a flyby of the moon. These gravity assists will help JUICE eventually reach Jupiter. Image via ESA.

JUICE mission launched on April 14, 2023

ESA‘s JUICE mission launched on April 14, 2023, after a one-day delay due to lightning at ESA’s spaceport in French Guiana. The spacecraft lifted off successfully into cloudy skies, beginning a multi-year mission to Jupiter and its icy moons.

As often happens with missions to the outer solar system, the spacecraft will take a circuitous route to Jupiter, making multiple sweeps past the Earth, moon and Venus. Then, in 2031, it’ll arrive at the giant planet. At that time it’ll perform 35 flybys of the Galilean moons Ganymede, Callisto and Europa, before going into orbit around the largest moon, Ganymede.

JUICE stands for JUpiter Icy Moons Explorer.

View larger. | This is JUICE’s journey to Jupiter. It will become a reality (fingers crossed) in July 2031, when JUICE is scheduled to arrive at Jupiter. It’s impressive, especially considering the spacecraft will still be soaring around Earth in 2029! Only when it has completed its 2nd flyby of our home planet will JUICE make a quick 2-year hop to Jupiter. There, it’ll complete 35 flybys of the giant planet’s 3 largest moons: Ganymede, Callisto, and Europa (pictured 1st, 5th, and 4th from the left, respectively). Image via ESA.

Jammed antenna

The JUICE mission’s primary antenna jammed soon after launch. But after three weeks of troubleshooting, engineers finally managed to fix the antenna. As the spacecraft traveled through deep space, JUICE mission control tried using thrusters to shake the antenna. Then they tried warming the jammed components in the sun’s rays. Finally, the team fired a mechanical device called an actuator. And that’s what made the antenna break free from its stuck position on May 12, 2023. This RIME antenna, which stands for Radar for Icy Moons Exploration, will be used to study the structure of Jupiter’s icy moons down to a depth of 5.5 miles (9 km) when it finally reaches the gas giant in July 2031.

? Shocking RIME update ?

The RIME antenna on @ESA_JUICE is free!!!

This Juice Monitoring Camera GIF shows the moments after the Flight Control Team at ESA #MissionControl fired the remaining 'actuator' on the jammed bracket.

More info: https://t.co/QzZdleTdgt pic.twitter.com/T96RIg3hKA

— ESA Operations (@esaoperations) May 12, 2023

JUICE mission goals

ESA said its goals for JUICE are to:

… make detailed observations of the giant gas planet and its three large ocean-bearing moons – Ganymede, Callisto and Europa – with a suite of remote sensing, geophysical and in situ instruments.

And, ESA said, the mission will characterize these moons as both planetary objects and possible habitats.

ESA hopes that a wider study of the Jupiter system can be used as an archetype for gas giant planets and their moons across our Milky Way galaxy.

Liftoff for humankind’s next bold mission to the outer Solar System – #ESAJuice onboard @Ariane5 #VA260 ? ?#DestinationJupiter #ExploreFarther https://t.co/nuYjsCR6Ar

— ESA's Juice mission (@ESA_JUICE) April 14, 2023

Why JUICE will study Europa

JUICE will arrive at Jupiter in 2031. One of the moons it will observe is perhaps the most fascinating of the Jovian moons to Earthly scientists: Europa. This moon is thought to have an ocean of liquid water under its icy crust (also made of water ice). And JUICE is designed to look for the sort of chemistry on Europa that is essential to life on Earth, for example organic molecules, or molecules containing carbon that are key to life on Earth.

JUICE also aims to understand the formation of Europa’s surface features and the composition of any non-water-ice material.

Why JUICE will study Ganymede

After a series of flybys of Jupiter and three of its large, icy moons, JUICE will eventually settle into an orbit around the largest moon, Ganymede. JUICE will orbit Ganymede down to 125 miles (200 km) for about three years. It’ll end its mission with an impact on the moon’s surface.

While at Ganymede, JUICE has many science objectives. They include:

• Characterization of the ocean layers and detection of possible subsurface water reservoirs.
• Topographical, geological and compositional mapping of the surface.
• Study of the physical properties of the icy crust.
• Characterization of the internal mass distribution, dynamics and evolution of the interior.
• Investigation of the exosphere.
• Study of Ganymede’s intrinsic magnetic field and its interactions with the Jovian magnetosphere.

Having a better understanding of this wet, cold world will also help us understand possible distant worlds around other suns, scientists say.

JUICE mocktails

Earlier this year, ESA had a little fun with the acronym JUICE, by holding a space juice contest. Check out these beautiful mocktails, and find the recipes here.

Having a little fun with the JUICE mission, these were the winners of ESA’s space juice contest. The mocktails included some made by 7 and 11-year-olds. Image via ESA.

JUICE art, from kids

ESA also invited kids from around the world to create JUICE-inspired artwork. Read more about the contest here. The winning entry – submitted by 8-year-old Yaryna from Ukraine – is going to space! It’s painted on the Ariane 5 rocket which will launch JUICE.

Did you spot the beautiful artwork on the nose of the #Ariane5 fairing? Children from all over the world were invited to create a piece of art inspired by #ESAJuice and the winning design by ten-year-old Yaryna can be seen here. https://t.co/3wj377p0md pic.twitter.com/i5c7aGbTmw

— ESA's Juice mission (@ESA_JUICE) April 12, 2023

Bottom line: The JUICE mission will perform the world’s 1st-ever double gravity assist – a flyby of the moon and Earth – on August 19 and 20, 2024.

Read more: Icy moons’ puzzling features may be due to salty ice

The post JUICE mission to Jupiter to sweep past moon and Earth this week first appeared on EarthSky.

from EarthSky https://ift.tt/OIbgu5h

A solitary star speeding across the Milky Way

The short video shows a hypothetical white dwarf star, exploding as a supernova and pushing a 2nd star out of this binary system at a speed of some 1 million miles per hour. This scenario is one explanation for the discovery of a solitary star speeding across our Milky Way galaxy. The fast star is called a hypervelocity star, in this case labeled CWISE J1249. Image via Adam Makarenko/ video via Keck Observatory.

• Citizen scientists discovered a super-speedy star. It’s moving so fast that it’ll leave our galaxy, the Milky Way. Its speed is about 1 million miles per hour, in contrast to about 450 thousand miles per hour for our sun and solar system (!).
• Scientists call such stars hypervelocity stars. This one is labeled CWISE J1249, and it’s the smallest-mass hypervelocity star found so far. It’s also the closest one to our sun.
• Could this star be a brown dwarf? Maybe. It’s small and might be either a low-mass star or a brown dwarf, which is like a mix between a big planet and a star.

NASA originally published this article on August 15, 2024. Edits by EarthSky.

A solitary star speeding across our galaxy

Most familiar stars peacefully orbit the center of the Milky Way. But citizen scientists working on NASA’s Backyard Worlds: Planet 9 project have helped discover an object moving so fast that it will escape the Milky Way’s gravity and shoot into intergalactic space.

This hypervelocity object is the first such object found with the mass of a small star. It’s also the closest hypervelocity star to our sun.

The Backyard Worlds project uses images from NASA’s WISE (Wide-field Infrared Explorer) mission, which mapped the sky in infrared light from 2009 to 2011. It was reactivated as NEOWISE (Near-Earth Object Wide-field Infrared Survey Explorer) in 2013, and retired on August 8, 2024.

A few years ago, longtime Backyard Worlds citizen scientists Martin Kabatnik, Thomas P. Bickle, and Dan Caselden spotted a faint, fast-moving object called CWISE J124909.08+362116.0 marching across their screens in the WISE images. Follow-up observations with several ground-based telescopes helped scientists confirm the discovery and characterize the object. These citizen scientists are now co-authors on the team’s study about this discovery, to be published in the Astrophysical Journal Letters (a pre-print version is available here). Kabatnik, a citizen scientist from Nuremberg, Germany, said:

I can’t describe the level of excitement. When I first saw how fast it was moving, I was convinced it must have been reported already.

Low-mass star or brown dwarf?

CWISE J1249 is zooming out of the Milky Way at about 1 million miles per hour (1.6 million kph). But it also stands out for its low mass, which makes it difficult to classify as a celestial object. It could be a low-mass star. But if it doesn’t steadily fuse hydrogen in its core, it would be considered a brown dwarf, somewhere between a gas giant planet and a star.

Ordinary brown dwarfs are not that rare. Backyard Worlds: Planet 9 volunteers have discovered more than 4,000 of them! But none of the others are known to be on their way out of the galaxy.

This new object has yet another unique property. Data obtained with the W. M. Keck Observatory in Maunakea, Hawaii, show that it has much less iron and other metals than other stars and brown dwarfs. This unusual composition suggests that CWISE J1249 is quite old, likely from one of the first generations of stars in our galaxy.

Why is the star so fast?

Why does this object move at such high speed? One theory is that CWISE J1249 originally came from a binary system with a white dwarf, which exploded as a supernova when it pulled off too much material from its companion. Another possibility is that it came from a tightly bound cluster of stars called a globular cluster, and a chance meeting with a pair of black holes sent it soaring away.

Kyle Kremer, incoming assistant professor in UC San Diego’s Department of Astronomy and Astrophysics, said:

When a star encounters a black hole binary, the complex dynamics of this three-body interaction can toss that star right out of the globular cluster.

Scientists will look more closely at the elemental composition of CWISE J1249 for clues about which of these scenarios is more likely.

A success for citizen science

This discovery has been a team effort on multiple levels: a collaboration involving volunteers, professionals, and students. Kabatnik credits other citizen scientists with helping him search, including Melina Thévenot. He said that Melina:

… blew my mind with her personal blog about doing searches using Astronomical Data Query Language.

Software written by citizen scientist Frank Kiwy was also instrumental in this finding, Kabatnik said.

The study is led by Backyard Worlds: Planet 9 science team member Adam Burgasser, a professor at the University of California, San Diego, and includes co-authors Hunter Brooks and Austin Rothermich, astronomy students who both began their astronomy careers as citizen scientists.

Want to help discover the next extraordinary space object? Join Backyard Worlds: Planet 9 here. Participation is open to anyone in any country worldwide.

Bottom line: Citizen scientists have discovered a solitary star moving so fast that it will eventually escape the Milky Way’s gravity and shoot into intergalactic space.

Via NASA

Via Keck Observatory

The post A solitary star speeding across the Milky Way first appeared on EarthSky.

from EarthSky https://ift.tt/XAbNv3r

The short video shows a hypothetical white dwarf star, exploding as a supernova and pushing a 2nd star out of this binary system at a speed of some 1 million miles per hour. This scenario is one explanation for the discovery of a solitary star speeding across our Milky Way galaxy. The fast star is called a hypervelocity star, in this case labeled CWISE J1249. Image via Adam Makarenko/ video via Keck Observatory.

• Citizen scientists discovered a super-speedy star. It’s moving so fast that it’ll leave our galaxy, the Milky Way. Its speed is about 1 million miles per hour, in contrast to about 450 thousand miles per hour for our sun and solar system (!).
• Scientists call such stars hypervelocity stars. This one is labeled CWISE J1249, and it’s the smallest-mass hypervelocity star found so far. It’s also the closest one to our sun.
• Could this star be a brown dwarf? Maybe. It’s small and might be either a low-mass star or a brown dwarf, which is like a mix between a big planet and a star.

NASA originally published this article on August 15, 2024. Edits by EarthSky.

A solitary star speeding across our galaxy

Most familiar stars peacefully orbit the center of the Milky Way. But citizen scientists working on NASA’s Backyard Worlds: Planet 9 project have helped discover an object moving so fast that it will escape the Milky Way’s gravity and shoot into intergalactic space.

This hypervelocity object is the first such object found with the mass of a small star. It’s also the closest hypervelocity star to our sun.

The Backyard Worlds project uses images from NASA’s WISE (Wide-field Infrared Explorer) mission, which mapped the sky in infrared light from 2009 to 2011. It was reactivated as NEOWISE (Near-Earth Object Wide-field Infrared Survey Explorer) in 2013, and retired on August 8, 2024.

A few years ago, longtime Backyard Worlds citizen scientists Martin Kabatnik, Thomas P. Bickle, and Dan Caselden spotted a faint, fast-moving object called CWISE J124909.08+362116.0 marching across their screens in the WISE images. Follow-up observations with several ground-based telescopes helped scientists confirm the discovery and characterize the object. These citizen scientists are now co-authors on the team’s study about this discovery, to be published in the Astrophysical Journal Letters (a pre-print version is available here). Kabatnik, a citizen scientist from Nuremberg, Germany, said:

I can’t describe the level of excitement. When I first saw how fast it was moving, I was convinced it must have been reported already.

Low-mass star or brown dwarf?

CWISE J1249 is zooming out of the Milky Way at about 1 million miles per hour (1.6 million kph). But it also stands out for its low mass, which makes it difficult to classify as a celestial object. It could be a low-mass star. But if it doesn’t steadily fuse hydrogen in its core, it would be considered a brown dwarf, somewhere between a gas giant planet and a star.

Ordinary brown dwarfs are not that rare. Backyard Worlds: Planet 9 volunteers have discovered more than 4,000 of them! But none of the others are known to be on their way out of the galaxy.

This new object has yet another unique property. Data obtained with the W. M. Keck Observatory in Maunakea, Hawaii, show that it has much less iron and other metals than other stars and brown dwarfs. This unusual composition suggests that CWISE J1249 is quite old, likely from one of the first generations of stars in our galaxy.

Why is the star so fast?

Why does this object move at such high speed? One theory is that CWISE J1249 originally came from a binary system with a white dwarf, which exploded as a supernova when it pulled off too much material from its companion. Another possibility is that it came from a tightly bound cluster of stars called a globular cluster, and a chance meeting with a pair of black holes sent it soaring away.

Kyle Kremer, incoming assistant professor in UC San Diego’s Department of Astronomy and Astrophysics, said:

When a star encounters a black hole binary, the complex dynamics of this three-body interaction can toss that star right out of the globular cluster.

Scientists will look more closely at the elemental composition of CWISE J1249 for clues about which of these scenarios is more likely.

A success for citizen science

This discovery has been a team effort on multiple levels: a collaboration involving volunteers, professionals, and students. Kabatnik credits other citizen scientists with helping him search, including Melina Thévenot. He said that Melina:

… blew my mind with her personal blog about doing searches using Astronomical Data Query Language.

Software written by citizen scientist Frank Kiwy was also instrumental in this finding, Kabatnik said.

The study is led by Backyard Worlds: Planet 9 science team member Adam Burgasser, a professor at the University of California, San Diego, and includes co-authors Hunter Brooks and Austin Rothermich, astronomy students who both began their astronomy careers as citizen scientists.

Want to help discover the next extraordinary space object? Join Backyard Worlds: Planet 9 here. Participation is open to anyone in any country worldwide.

Bottom line: Citizen scientists have discovered a solitary star moving so fast that it will eventually escape the Milky Way’s gravity and shoot into intergalactic space.

Via NASA

Via Keck Observatory

The post A solitary star speeding across the Milky Way first appeared on EarthSky.

from EarthSky https://ift.tt/XAbNv3r

Does a supermoon have a super effect on us?

View at EarthSky Community Photos. | Jean-Baptiste Feldmann in Gleizé, France, captured this image on August 30, 2023. Jean-Baptiste wrote: “The full supermoon appeared all red above the houses on the horizon, about 10 kilometers away. Her color was truly spectacular. I think I much prefer a red moon to a blue moon!” We love red moons, too! Thank you, Jean-Baptiste!

Next supermoon is August 19, 2024

The term supermoon denotes a new or full moon that occurs at roughly the same time the moon is nearest the Earth in its monthly orbit. In fact, there are four full supermoons in a row in 2024. We’re coming up on the first one, a seasonal blue moon supermoon. It’ll fall on August 19, lighting up the nighttime sky from dusk to dawn.

But sometimes people ask:

Does a supermoon have a super effect on us?

Does a supermoon’s gravity pull us harder?

Here’s the important question for this discussion.

Does the moon’s gravitational pull vary with its distance? The answer is, sure, it does. The moon pulls least on Earth when farthest away in its orbit (apogee, or farthest point from the planet). And it pulls most on Earth when closest to us (perigee).

But does that increased gravity matter to us as human beings? The answer is … no, it doesn’t.

And here’s why. Gravity depends on two things. It depends directly on the masses of the two objects being gravitationally attracted. And it depends inversely on the distance between the two objects.

So … “inversely on the distance between.” That just means what we said at the top of this section. The moon pulls most strongly on Earth when closest to us. And it pulls least strongly when farthest away.

But … “directly on the masses of the two objects being gravitationally attracted.” The more massive the object, the greater the pull of gravity. The Earth and moon are both very massive. So they exert a large gravitational pull on each other.

And that’s why a closer moon can cause especially large ocean tides. Earth’s oceans are very massive, too.

But are you very massive? No. Not compared to Earth’s oceans. Consider an average 176-pound (80-kilogram) human being. The maximum difference on a person between a close moon and a distant moon is about 73 milligrams. And that is about 1/14 the mass of an ordinary paper clip.

If you factor in the solar gravity effect for a supermoon, or full moon closest to Earth, this effect may rise to about 110 milligrams. And that is roughly equivalent to about 1/9 the mass of a paperclip.

In either case, the effects are imperceptible, and far smaller than those encountered in other everyday situations, for example, being near a mountain or even near a large building.

You can expect high tides near one

But, you might observe – like I said earlier – that an extra-close full moon causes higher-than-usual perigean tides. The tides are a very different situation from human beings. Tides work through what is called a differential gravitational effect. Specifically, the force of gravity exerted on the part of the Earth opposite the moon (the far side of Earth, as seen from the moon) is slightly less than the force of gravity exerted on the part of the Earth directly beneath the moon (the Earth’s near side, as seen from the moon) at any given time.

Why? It’s because there’s an additional distance – about 8,000 miles – from one side of Earth to the other. The force of gravity weakens rapidly with increasing distance, producing the differential.

View at EarthSky Community Photos. | Kamala Venkatesh of San Diego, California, captured this image of the August 1, 2023, full moon, sometimes called a Sturgeon Moon. It was also a supermoon. Kamala wrote: “If you didn’t see the Sturgeon supermoon, there’s one coming up at the end of August.” Thank you, Kamala!

The Earth is more rigid than the oceans

The result of this differential gravitational effect of the moon is that our planet is stretched slightly along a line between the Earth and moon. The body of the Earth is fairly rigid, so it does not stretch much. However, the oceans are much more easily moved. Thus, the effect piles up water on either side of Earth. And these piles of water – created by the differential gravitational effect – are the tides. Note that, on average, the tidal effect is quite small. It raises tides only a few feet across an 8,000-mile-wide planet Earth.

Technically, the same effect acts on your body as well, since one side is farther from the moon than the other. However, the difference in distance is on the order of one foot, rather than thousands of miles. Therefore, the differential is millions of times less, and the effect on a human body infinitesimally small and irrelevant.

About 3 or 4 times a year, a new or full moon coincides with the moon’s closest point to Earth, or perigee. There’s usually only a small difference – typically a couple of inches (or centimeters) – between these “perigean spring tides” and normal tidal ranges. But, at these times, if a storm strikes along a coastline, flooding can occur. Image via NOAA.

Supermoons do get a lot of attention

Supermoons are important because they focus attention on the moon and the sky in general. But the bottom line is that any physical effects of supermoons are not exactly super. There is no reasonable evidence that they cause super disasters. The effects that people may attribute to them are psychological rather than physical.

There are several supermoons this year and every year. To learn about supermoons in general try this EarthSky post: What is a supermoon?

Enjoying EarthSky? Sign up for our free daily newsletter today!

View at EarthSky Community Photos. | Mickey Walters of Jamestown, Rhode Island, captured this image on August 1, 2023. Mickey wrote: “Sturgeon Full Moon from Narragansett Bay, overlooking Newport, Rhode Island.” Thank you, Mickey!

Can you notice a difference in the size of supermoons?

So, does the change in distance between the moon’s farthest and closest points make it appear smaller and bigger? In fact, the full supermoon can appear as much as 14% larger in the sky and 30% brighter to our eyes than at minimum size and brightness.

However, these changes do not come all of a sudden from month to month. But, without anything with to compare them with, the changes in the moon’s size or brightness are hard to quantify by simple observation. To notice the difference, you would need to see the apogean (smallest) full moon and the perigean (largest) full moon side by side.

For most of us, it’s only possible through photography or through some form of direct measurement. Although, careful observers have claimed to be able to discern a supermoon’s extra large size with the eye.

View at EarthSky Community Photos. | Tameem Altameemi of Dubai, United Arab Emirates, made this composite image and wrote: “I photographed the moon today, August 1, 2023, in perihelion, at a distance of 357,550 km. And I photographed the moon on February 5, 2023, when it was at aphelion 401,751 km. I took them with the same telescope and camera, showing the difference between them.” Thank you, Tameem!

Where did the term supermoon originate?

An astrologer, not an astronomer, coined the term supermoon, and it has come into wide usage recently. It’s an example of modern folklore, largely accepted and spread by a now-global community, via word of mouth and the internet.

In astronomy and other sciences, a related term – perigean tides – refers to the higher tides that can occur when a new or full moon and the month’s perigee coincide, as they frequently do. Simply put, an extra-close new or full moon causes higher-than-usual perigean tides.

View at EarthSky Community Photos. | Lorraine Boyd of Delmar, New York, captured this image on August 1, 2023. Lorraine wrote: “The Full Sturgeon Moon, also the first of 2 supermoons in August 2023. The official term for a supermoon is a ‘perigean full moon’. It was such a beautiful, finally very cool, clear night.” Thank you, Lorraine!

Bottom line: Sure, the moon (and sun) creates the tides. And an extra-close moon can create higher-than-usual tides. But this doesn’t mean that an extra-close new or full moon – a supermoon – has an effect on human beings. In fact, the effects of a supermoon are imperceptible, and far smaller than those encountered in other everyday situations, such as being near a mountain or even a large building. Of course, that beautiful bright full supermoon will draw your eyes to the sky.

The post Does a supermoon have a super effect on us? first appeared on EarthSky.

from EarthSky https://ift.tt/QYi1PSo

View at EarthSky Community Photos. | Jean-Baptiste Feldmann in Gleizé, France, captured this image on August 30, 2023. Jean-Baptiste wrote: “The full supermoon appeared all red above the houses on the horizon, about 10 kilometers away. Her color was truly spectacular. I think I much prefer a red moon to a blue moon!” We love red moons, too! Thank you, Jean-Baptiste!

Next supermoon is August 19, 2024

The term supermoon denotes a new or full moon that occurs at roughly the same time the moon is nearest the Earth in its monthly orbit. In fact, there are four full supermoons in a row in 2024. We’re coming up on the first one, a seasonal blue moon supermoon. It’ll fall on August 19, lighting up the nighttime sky from dusk to dawn.

But sometimes people ask:

Does a supermoon have a super effect on us?

Does a supermoon’s gravity pull us harder?

Here’s the important question for this discussion.

Does the moon’s gravitational pull vary with its distance? The answer is, sure, it does. The moon pulls least on Earth when farthest away in its orbit (apogee, or farthest point from the planet). And it pulls most on Earth when closest to us (perigee).

But does that increased gravity matter to us as human beings? The answer is … no, it doesn’t.

And here’s why. Gravity depends on two things. It depends directly on the masses of the two objects being gravitationally attracted. And it depends inversely on the distance between the two objects.

So … “inversely on the distance between.” That just means what we said at the top of this section. The moon pulls most strongly on Earth when closest to us. And it pulls least strongly when farthest away.

But … “directly on the masses of the two objects being gravitationally attracted.” The more massive the object, the greater the pull of gravity. The Earth and moon are both very massive. So they exert a large gravitational pull on each other.

And that’s why a closer moon can cause especially large ocean tides. Earth’s oceans are very massive, too.

But are you very massive? No. Not compared to Earth’s oceans. Consider an average 176-pound (80-kilogram) human being. The maximum difference on a person between a close moon and a distant moon is about 73 milligrams. And that is about 1/14 the mass of an ordinary paper clip.

If you factor in the solar gravity effect for a supermoon, or full moon closest to Earth, this effect may rise to about 110 milligrams. And that is roughly equivalent to about 1/9 the mass of a paperclip.

In either case, the effects are imperceptible, and far smaller than those encountered in other everyday situations, for example, being near a mountain or even near a large building.

You can expect high tides near one

But, you might observe – like I said earlier – that an extra-close full moon causes higher-than-usual perigean tides. The tides are a very different situation from human beings. Tides work through what is called a differential gravitational effect. Specifically, the force of gravity exerted on the part of the Earth opposite the moon (the far side of Earth, as seen from the moon) is slightly less than the force of gravity exerted on the part of the Earth directly beneath the moon (the Earth’s near side, as seen from the moon) at any given time.

Why? It’s because there’s an additional distance – about 8,000 miles – from one side of Earth to the other. The force of gravity weakens rapidly with increasing distance, producing the differential.

View at EarthSky Community Photos. | Kamala Venkatesh of San Diego, California, captured this image of the August 1, 2023, full moon, sometimes called a Sturgeon Moon. It was also a supermoon. Kamala wrote: “If you didn’t see the Sturgeon supermoon, there’s one coming up at the end of August.” Thank you, Kamala!

The Earth is more rigid than the oceans

The result of this differential gravitational effect of the moon is that our planet is stretched slightly along a line between the Earth and moon. The body of the Earth is fairly rigid, so it does not stretch much. However, the oceans are much more easily moved. Thus, the effect piles up water on either side of Earth. And these piles of water – created by the differential gravitational effect – are the tides. Note that, on average, the tidal effect is quite small. It raises tides only a few feet across an 8,000-mile-wide planet Earth.

Technically, the same effect acts on your body as well, since one side is farther from the moon than the other. However, the difference in distance is on the order of one foot, rather than thousands of miles. Therefore, the differential is millions of times less, and the effect on a human body infinitesimally small and irrelevant.

About 3 or 4 times a year, a new or full moon coincides with the moon’s closest point to Earth, or perigee. There’s usually only a small difference – typically a couple of inches (or centimeters) – between these “perigean spring tides” and normal tidal ranges. But, at these times, if a storm strikes along a coastline, flooding can occur. Image via NOAA.

Supermoons do get a lot of attention

Supermoons are important because they focus attention on the moon and the sky in general. But the bottom line is that any physical effects of supermoons are not exactly super. There is no reasonable evidence that they cause super disasters. The effects that people may attribute to them are psychological rather than physical.

There are several supermoons this year and every year. To learn about supermoons in general try this EarthSky post: What is a supermoon?

Enjoying EarthSky? Sign up for our free daily newsletter today!

View at EarthSky Community Photos. | Mickey Walters of Jamestown, Rhode Island, captured this image on August 1, 2023. Mickey wrote: “Sturgeon Full Moon from Narragansett Bay, overlooking Newport, Rhode Island.” Thank you, Mickey!

Can you notice a difference in the size of supermoons?

So, does the change in distance between the moon’s farthest and closest points make it appear smaller and bigger? In fact, the full supermoon can appear as much as 14% larger in the sky and 30% brighter to our eyes than at minimum size and brightness.

However, these changes do not come all of a sudden from month to month. But, without anything with to compare them with, the changes in the moon’s size or brightness are hard to quantify by simple observation. To notice the difference, you would need to see the apogean (smallest) full moon and the perigean (largest) full moon side by side.

For most of us, it’s only possible through photography or through some form of direct measurement. Although, careful observers have claimed to be able to discern a supermoon’s extra large size with the eye.

View at EarthSky Community Photos. | Tameem Altameemi of Dubai, United Arab Emirates, made this composite image and wrote: “I photographed the moon today, August 1, 2023, in perihelion, at a distance of 357,550 km. And I photographed the moon on February 5, 2023, when it was at aphelion 401,751 km. I took them with the same telescope and camera, showing the difference between them.” Thank you, Tameem!

Where did the term supermoon originate?

An astrologer, not an astronomer, coined the term supermoon, and it has come into wide usage recently. It’s an example of modern folklore, largely accepted and spread by a now-global community, via word of mouth and the internet.

In astronomy and other sciences, a related term – perigean tides – refers to the higher tides that can occur when a new or full moon and the month’s perigee coincide, as they frequently do. Simply put, an extra-close new or full moon causes higher-than-usual perigean tides.

View at EarthSky Community Photos. | Lorraine Boyd of Delmar, New York, captured this image on August 1, 2023. Lorraine wrote: “The Full Sturgeon Moon, also the first of 2 supermoons in August 2023. The official term for a supermoon is a ‘perigean full moon’. It was such a beautiful, finally very cool, clear night.” Thank you, Lorraine!

Bottom line: Sure, the moon (and sun) creates the tides. And an extra-close moon can create higher-than-usual tides. But this doesn’t mean that an extra-close new or full moon – a supermoon – has an effect on human beings. In fact, the effects of a supermoon are imperceptible, and far smaller than those encountered in other everyday situations, such as being near a mountain or even a large building. Of course, that beautiful bright full supermoon will draw your eyes to the sky.

The post Does a supermoon have a super effect on us? first appeared on EarthSky.

from EarthSky https://ift.tt/QYi1PSo

Asaph Hall finds Mars moon Phobos 147 years ago

Asaph Hall discovered Phobos on August 17, 1877. This image of the large crater Stickney on the Martian moon Phobos is color-enhanced. The crater is 5.6 miles (9 km) in diameter, so it covers a substantial proportion of Phobos’ surface. The impact almost destroyed the small moon! Notice the smaller crater within Stickney, about 1.2 miles (2 km) in diameter, resulting from a later impact. Image via HiRISE/ MRO/ LPL (U. Arizona)/ NASA.

August 17, 1877: Asaph Hall discovers Phobos

On August 17, 147 years ago, American astronomer Asaph Hall discovered the first known moon for our neighboring planet, Mars. Later that year, he found a second Martian moon. Today, we call the first and larger moon Phobos. And we call the second and smaller one Deimos.

To date, Phobos and Deimos remain the only known moons of Mars.

Both Phobos and Deimos are potato-shaped. They look more like asteroids than like Earth’s much-larger companion moon. In fact, it’s likely that Mars captured these little worlds that now orbit the red planet. Studies have indicated that – millions of years from now – Phobos will shatter and form a ring around Mars. Some astronomers think Phobos alternates between being a planetary ring, then clumping up again to form a moon. More about ring theories of Phobos below.

Phobos and Deimos, fear and terror

The names Phobos and Deimos mean fear and terror, respectively. Their names refer to the mythological horses that pulled the chariot of the Greek war god Ares. He was the Greek counterpart to the Roman war god Mars.

So, although it’s the larger of Mars’ two moons, Phobos is tiny. It has a mean diameter of only about 14 miles (22.2 km). But it’s seven times more massive than Deimos, which has a mean diameter of about 7.7 miles (12.4 km). For these moons, we’re speaking in terms of a mean diameter because both moons are oblong in shape and not spherical. In contrast, Earth’s moon is nearly round, since it’s large enough for its gravity to have pulled it into a spherical shape.

Earth’s moon is also much larger (2,159 miles or 3,475 km in diameter). Since both Phobos and Deimos are so tiny, they have very weak gravity. And that means they don’t have enough gravity to make them round.

Mariner 9 was 1st to see them close

During Mariner 9’s mission to Mars in 1971 and 1972, scientists got their first close-up look at Phobos. Just like asteroids, its oblong surface shows many small craters. But one large crater stood out as much bigger than the rest. Astronomers named it Stickney Crater, for Angeline Stickney: an American academic, suffragist and mathematician, and Asaph Hall’s wife.

Stickney looks like a giant hole on one end of Phobos. Whatever rocky body created it was almost big enough to have shattered the moon. It’s thought that, whenever the impact occurred, Phobos barely survived.

Viking I image of Phobos and its large crater Stickney. The spacecraft captured this image in June 1977, 100 years after the discovery of Phobos. Image via NASA/ ESA.

A closer view of the grooves on Phobos. Image via NASA/ JPL-Caltech/ University of Arizona.

The Viking orbiter obtained this global map of Phobos. Image via Astrogeology Science Center/ Planetary Data System/ Phil Stooke.

Was Phobos once a ring? Will it be again?

Phobos has long, shallow grooves running across its surface, radiating away from Stickney. Many planetary scientists believe these grooves are early signs of eventual structural failure in the moon. They say it’s possible that – some 50 million years from now – Phobos will break apart, forming a ring around Mars.

A study in 2018 suggested that rolling boulders created the grooves, spraying across the surface during impact. As Ken Ramsley, a planetary science researcher at Brown University who led the work, explained:

These grooves are a distinctive feature of Phobos, and planetary scientists have been debating how they formed for 40 years. We think this study is another step toward zeroing in on an explanation.

More ring theories

In 2017, a new theory by Purdue University scientists suggested Phobos might not only break apart and form a ring around the planet but also suggests this ring formation happened before.

David Minton, a professor, and Andrew Hesselbrock, a doctoral student, both at Purdue, developed a computer model showing debris ejected into space from an asteroid or other body slamming into Mars. This event – some 4.3 billion years ago – would cause the material to now alternate between becoming a planetary ring and clumping up again to form the moon Phobos.

Size and visual comparison of Phobos (left) and Deimos (right). Image via NASA.

Daily Owl #Fact

One day #Mars will have a ring around it?

In the next 20-40 million years Mars’ largest moon Phobos will be torn apart by gravitational forces leading to the creation of a ring that could last up to 100 million years#NFTs #Moon #Space pic.twitter.com/IIYHCkgDhf

— MarsBirds? (@mars_birds) July 12, 2022

Deimos played a role

Another study, from scientists at Purdue and the SETI Institute in June 2020, also concluded that Mars used to have a ring or series of rings. The scientists based that study on an analysis of the orbit of the other Martian moon, Deimos.

Deimos is smaller than Phobos. And it has an orbit that’s tilted with respect to Mars’ equator by about 2 degrees. Meanwhile, Phobos’ orbit isn’t inclined as much. The larger moon is inclined to Mars’ equator by only about 1 degree. The scientists said in a statement:

These orbital resonances are picky but predictable … We can tell that only an outward-moving moon could have strongly affected Deimos, which means that Mars must have had a ring pushing the inner moon outward … This moon may have been 20 times as massive as Phobos, and may have been its ‘grandparent’ existing just over 3 billion years ago … [It] was followed by two more ring-moon cycles, with the latest moon being Phobos.

So, basically, there may have been a moon about 20 times more massive than Phobos, and Mars’ rings pushed it outward. And at least two times since then, that moon broke apart and then formed a new ring, before the material coalesced together again to form a new moon. Phobos is now that current moon. The scientists say it will eventually break apart to form a new ring, thus continuing the cycle.

Scientists also now know Phobos is much younger than Deimos – perhaps only 200 million years old – which would fit the moon/ring scenario. The Phobos we see today is simply a newer and smaller version of its original self.

Eclipsing moons

Asaph Hall probably never imagined the idea of Phobos breaking apart and forming a ring around Mars. And he couldn’t possibly have imagined the video below, which was acquired by NASA’s Mars rover Curiosity on August 1, 2013. This video shows both moons, Phobos and Deimos, as you might see them while standing on the surface of Mars. You can clearly see some of the large craters on Phobos in these images.

This was the first time that images taken from Mars’ surface caught one moon eclipsing the other … but probably not the last.

Bottom line: On this date in 1877, American astronomer Asaph Hall discovered Phobos, the larger of Mars’ 2 moons. He discovered the other moon, Deimos, later that year.

The post Asaph Hall finds Mars moon Phobos 147 years ago first appeared on EarthSky.

from EarthSky https://ift.tt/SHuXiBv

Asaph Hall discovered Phobos on August 17, 1877. This image of the large crater Stickney on the Martian moon Phobos is color-enhanced. The crater is 5.6 miles (9 km) in diameter, so it covers a substantial proportion of Phobos’ surface. The impact almost destroyed the small moon! Notice the smaller crater within Stickney, about 1.2 miles (2 km) in diameter, resulting from a later impact. Image via HiRISE/ MRO/ LPL (U. Arizona)/ NASA.

August 17, 1877: Asaph Hall discovers Phobos

On August 17, 147 years ago, American astronomer Asaph Hall discovered the first known moon for our neighboring planet, Mars. Later that year, he found a second Martian moon. Today, we call the first and larger moon Phobos. And we call the second and smaller one Deimos.

To date, Phobos and Deimos remain the only known moons of Mars.

Both Phobos and Deimos are potato-shaped. They look more like asteroids than like Earth’s much-larger companion moon. In fact, it’s likely that Mars captured these little worlds that now orbit the red planet. Studies have indicated that – millions of years from now – Phobos will shatter and form a ring around Mars. Some astronomers think Phobos alternates between being a planetary ring, then clumping up again to form a moon. More about ring theories of Phobos below.

Phobos and Deimos, fear and terror

The names Phobos and Deimos mean fear and terror, respectively. Their names refer to the mythological horses that pulled the chariot of the Greek war god Ares. He was the Greek counterpart to the Roman war god Mars.

So, although it’s the larger of Mars’ two moons, Phobos is tiny. It has a mean diameter of only about 14 miles (22.2 km). But it’s seven times more massive than Deimos, which has a mean diameter of about 7.7 miles (12.4 km). For these moons, we’re speaking in terms of a mean diameter because both moons are oblong in shape and not spherical. In contrast, Earth’s moon is nearly round, since it’s large enough for its gravity to have pulled it into a spherical shape.

Earth’s moon is also much larger (2,159 miles or 3,475 km in diameter). Since both Phobos and Deimos are so tiny, they have very weak gravity. And that means they don’t have enough gravity to make them round.

Mariner 9 was 1st to see them close

During Mariner 9’s mission to Mars in 1971 and 1972, scientists got their first close-up look at Phobos. Just like asteroids, its oblong surface shows many small craters. But one large crater stood out as much bigger than the rest. Astronomers named it Stickney Crater, for Angeline Stickney: an American academic, suffragist and mathematician, and Asaph Hall’s wife.

Stickney looks like a giant hole on one end of Phobos. Whatever rocky body created it was almost big enough to have shattered the moon. It’s thought that, whenever the impact occurred, Phobos barely survived.

Viking I image of Phobos and its large crater Stickney. The spacecraft captured this image in June 1977, 100 years after the discovery of Phobos. Image via NASA/ ESA.

A closer view of the grooves on Phobos. Image via NASA/ JPL-Caltech/ University of Arizona.

The Viking orbiter obtained this global map of Phobos. Image via Astrogeology Science Center/ Planetary Data System/ Phil Stooke.

Was Phobos once a ring? Will it be again?

Phobos has long, shallow grooves running across its surface, radiating away from Stickney. Many planetary scientists believe these grooves are early signs of eventual structural failure in the moon. They say it’s possible that – some 50 million years from now – Phobos will break apart, forming a ring around Mars.

A study in 2018 suggested that rolling boulders created the grooves, spraying across the surface during impact. As Ken Ramsley, a planetary science researcher at Brown University who led the work, explained:

These grooves are a distinctive feature of Phobos, and planetary scientists have been debating how they formed for 40 years. We think this study is another step toward zeroing in on an explanation.

More ring theories

In 2017, a new theory by Purdue University scientists suggested Phobos might not only break apart and form a ring around the planet but also suggests this ring formation happened before.

David Minton, a professor, and Andrew Hesselbrock, a doctoral student, both at Purdue, developed a computer model showing debris ejected into space from an asteroid or other body slamming into Mars. This event – some 4.3 billion years ago – would cause the material to now alternate between becoming a planetary ring and clumping up again to form the moon Phobos.

Size and visual comparison of Phobos (left) and Deimos (right). Image via NASA.

Daily Owl #Fact

One day #Mars will have a ring around it?

In the next 20-40 million years Mars’ largest moon Phobos will be torn apart by gravitational forces leading to the creation of a ring that could last up to 100 million years#NFTs #Moon #Space pic.twitter.com/IIYHCkgDhf

— MarsBirds? (@mars_birds) July 12, 2022

Deimos played a role

Another study, from scientists at Purdue and the SETI Institute in June 2020, also concluded that Mars used to have a ring or series of rings. The scientists based that study on an analysis of the orbit of the other Martian moon, Deimos.

Deimos is smaller than Phobos. And it has an orbit that’s tilted with respect to Mars’ equator by about 2 degrees. Meanwhile, Phobos’ orbit isn’t inclined as much. The larger moon is inclined to Mars’ equator by only about 1 degree. The scientists said in a statement:

These orbital resonances are picky but predictable … We can tell that only an outward-moving moon could have strongly affected Deimos, which means that Mars must have had a ring pushing the inner moon outward … This moon may have been 20 times as massive as Phobos, and may have been its ‘grandparent’ existing just over 3 billion years ago … [It] was followed by two more ring-moon cycles, with the latest moon being Phobos.

So, basically, there may have been a moon about 20 times more massive than Phobos, and Mars’ rings pushed it outward. And at least two times since then, that moon broke apart and then formed a new ring, before the material coalesced together again to form a new moon. Phobos is now that current moon. The scientists say it will eventually break apart to form a new ring, thus continuing the cycle.

Scientists also now know Phobos is much younger than Deimos – perhaps only 200 million years old – which would fit the moon/ring scenario. The Phobos we see today is simply a newer and smaller version of its original self.

Eclipsing moons

Asaph Hall probably never imagined the idea of Phobos breaking apart and forming a ring around Mars. And he couldn’t possibly have imagined the video below, which was acquired by NASA’s Mars rover Curiosity on August 1, 2013. This video shows both moons, Phobos and Deimos, as you might see them while standing on the surface of Mars. You can clearly see some of the large craters on Phobos in these images.

This was the first time that images taken from Mars’ surface caught one moon eclipsing the other … but probably not the last.

Bottom line: On this date in 1877, American astronomer Asaph Hall discovered Phobos, the larger of Mars’ 2 moons. He discovered the other moon, Deimos, later that year.

The post Asaph Hall finds Mars moon Phobos 147 years ago first appeared on EarthSky.

from EarthSky https://ift.tt/SHuXiBv

The August full moon is also a Blue supermoon

The August full moon happens at 18:26 UTC (1:26 p.m. CDT) on August 19. For everyone around the globe, the moon will rise – round and nearly or entirely full – in the east just after sunset that evening. Plus, the August 19 full moon will lie near Saturn. It’s the 1st of 4 full supermoons in a row. And it’s a Blue Moon. Chart via EarthSky.

When to watch in 2024: Overnight of August 19-20.
Where to look: Look for the bright round moon in the east on the evening of August 19, highest in the sky around midnight, and in the west before sunrise on the morning of August 20.
Crest of the full moon falls at 18:26 UTC (1:26 p.m. CDT) on August 19.
It’s a supermoon, the first of four in a row.
It’s a Blue Moon, the third of four full moons in a single season.

All full moons rise along the eastern horizon near sunset, and set along the western horizon near sunrise. So, they are visible all night. At full moon, the sun, Earth and moon are aligned in space, with Earth in the middle. The moon’s day side – its fully lighted hemisphere – directly faces us. That’s why the moon appears full. Also, note that the moon will look full and round the day before and the day after it reaches its fullest.

At full moon, the sun, Earth and moon are aligned with Earth in the middle. The moon’s day side – its fully lighted hemisphere – directly faces us.

The August full moon is a supermoon

August 2024 sees lunar perigee – the point in the moon’s orbit where it comes closest to Earth – occur about 36 hours after the crest of the August 19 full moon. Perigee happens at 5 UTC (or 12 a.m. CDT) on August 21.

The time of full moon – and the time of perigee – are so close that Fred Espenak and others list this full moon on their supermoon tables. However, a supermoon doesn’t look bigger to the eye alone. But it does look brighter. And sometimes particularly high tides will follow supermoons by a day or so.

Furthermore, the August 19 supermoon is the first of four supermoons in a row.

The 2024 August full moon falls 36 hours before it reaches its closet point to Earth, called perigee. Because the full moon is closer than it is along most other places in its orbit around Earth, it appears brighter in the sky. This makes it a supermoon. Chart via EarthSky.

It’s also a Blue Moon

What is a Blue Moon? First, it can be the second of two full moons in a calendar month. Or it can be the third of four full moons in a single season.

Our last Blue Moon came on August 30-31, 2023. That night, the Blue Moon was near the planet Saturn. And that full moon – like most Blue Moons – was a monthly blue moon.

The Blue Moon on August 19, 2024, is a seasonal blue moon, that’s because it’s the third of four full moons in a season (the time between a solstice and an equinox). By the way – just like last year – the August full supermoon is near Saturn.

Read more about Blue Moons

It’s the Sturgeon Moon

All the full moons have names. For example, popular names for the August full moon include the Flying Up Moon, Corn Moon and Sturgeon Moon. The name Sturgeon Moon recognizes the August peak of the sturgeon fish catch in the waters of the Great Lakes.

Read more: Full moon names by month and by seasonRead more: Traditional full moon names and their meanings

Full Moon near Saturn

In addition, a point of light – Saturn – shines near the full moon this August. The following night, the moon will lie close to Saturn, making Saturn difficult to spot because of the bright moonlight.

The 2024 August full moon falls in the early afternoon on August 19 (at 1:26 p.m. CDT) and lies in the constellation Capricornus. Chart via EarthSky.

On the evening of August 20, the waning gibbous moon will lie close to Saturn. They’ll rise in the east a little after sunset. Chart via EarthSky.

August full moon falls in Capricornus in 2024

The August full moon can lie in front of one of two constellations of the zodiac. The one most often is Capricornus, the Sea-goat, while the other is Aquarius, the Water carrier. As seen from the Americas, the full moon on the night of August 19, 2024, will be located in the direction of central Capricornus. Because of the bright moonlight, the stars in the vicinity of the moon will be difficult to see with the unaided eye.

Bottom line: The full Corn Moon or Sturgeon Moon happens overnight on August 19, 2024. It’s also a full supermoon and will lie near Saturn. Plus, it’s a seasonal Blue Moon. Check it out!

The post The August full moon is also a Blue supermoon first appeared on EarthSky.

from EarthSky https://ift.tt/yqoC6wg

The August full moon happens at 18:26 UTC (1:26 p.m. CDT) on August 19. For everyone around the globe, the moon will rise – round and nearly or entirely full – in the east just after sunset that evening. Plus, the August 19 full moon will lie near Saturn. It’s the 1st of 4 full supermoons in a row. And it’s a Blue Moon. Chart via EarthSky.

When to watch in 2024: Overnight of August 19-20.
Where to look: Look for the bright round moon in the east on the evening of August 19, highest in the sky around midnight, and in the west before sunrise on the morning of August 20.
Crest of the full moon falls at 18:26 UTC (1:26 p.m. CDT) on August 19.
It’s a supermoon, the first of four in a row.
It’s a Blue Moon, the third of four full moons in a single season.

All full moons rise along the eastern horizon near sunset, and set along the western horizon near sunrise. So, they are visible all night. At full moon, the sun, Earth and moon are aligned in space, with Earth in the middle. The moon’s day side – its fully lighted hemisphere – directly faces us. That’s why the moon appears full. Also, note that the moon will look full and round the day before and the day after it reaches its fullest.

At full moon, the sun, Earth and moon are aligned with Earth in the middle. The moon’s day side – its fully lighted hemisphere – directly faces us.

The August full moon is a supermoon

August 2024 sees lunar perigee – the point in the moon’s orbit where it comes closest to Earth – occur about 36 hours after the crest of the August 19 full moon. Perigee happens at 5 UTC (or 12 a.m. CDT) on August 21.

The time of full moon – and the time of perigee – are so close that Fred Espenak and others list this full moon on their supermoon tables. However, a supermoon doesn’t look bigger to the eye alone. But it does look brighter. And sometimes particularly high tides will follow supermoons by a day or so.

Furthermore, the August 19 supermoon is the first of four supermoons in a row.

The 2024 August full moon falls 36 hours before it reaches its closet point to Earth, called perigee. Because the full moon is closer than it is along most other places in its orbit around Earth, it appears brighter in the sky. This makes it a supermoon. Chart via EarthSky.

It’s also a Blue Moon

What is a Blue Moon? First, it can be the second of two full moons in a calendar month. Or it can be the third of four full moons in a single season.

Our last Blue Moon came on August 30-31, 2023. That night, the Blue Moon was near the planet Saturn. And that full moon – like most Blue Moons – was a monthly blue moon.

The Blue Moon on August 19, 2024, is a seasonal blue moon, that’s because it’s the third of four full moons in a season (the time between a solstice and an equinox). By the way – just like last year – the August full supermoon is near Saturn.

Read more about Blue Moons

It’s the Sturgeon Moon

All the full moons have names. For example, popular names for the August full moon include the Flying Up Moon, Corn Moon and Sturgeon Moon. The name Sturgeon Moon recognizes the August peak of the sturgeon fish catch in the waters of the Great Lakes.

Read more: Full moon names by month and by seasonRead more: Traditional full moon names and their meanings

Full Moon near Saturn

In addition, a point of light – Saturn – shines near the full moon this August. The following night, the moon will lie close to Saturn, making Saturn difficult to spot because of the bright moonlight.

The 2024 August full moon falls in the early afternoon on August 19 (at 1:26 p.m. CDT) and lies in the constellation Capricornus. Chart via EarthSky.

On the evening of August 20, the waning gibbous moon will lie close to Saturn. They’ll rise in the east a little after sunset. Chart via EarthSky.

August full moon falls in Capricornus in 2024

The August full moon can lie in front of one of two constellations of the zodiac. The one most often is Capricornus, the Sea-goat, while the other is Aquarius, the Water carrier. As seen from the Americas, the full moon on the night of August 19, 2024, will be located in the direction of central Capricornus. Because of the bright moonlight, the stars in the vicinity of the moon will be difficult to see with the unaided eye.

Bottom line: The full Corn Moon or Sturgeon Moon happens overnight on August 19, 2024. It’s also a full supermoon and will lie near Saturn. Plus, it’s a seasonal Blue Moon. Check it out!

The post The August full moon is also a Blue supermoon first appeared on EarthSky.

from EarthSky https://ift.tt/yqoC6wg