Why clouds form near black holes

Multicolored areas against black background and a fuzzy dark ring with a bright light shining from its center.

This artist’s concept depicts a quasar, a type of active galactic nucleus, surrounded by a dusty donut shape (torus) and clumps called “clouds.” These clouds start small but can expand to be more than 1 parsec (3.3 light-years) wide. In this diagram, the clouds are at least 1 parsec from the torus. Image via Nima Abkenar/ NASA.

Via NASA

Once you leave the majestic skies of Earth, the word cloud no longer means a white fluffy-looking structure that produces rain. Instead, clouds in the greater universe are clumpy areas of greater density than their surroundings.

Space telescopes have observed these cosmic clouds in the vicinity of supermassive black holes, those mysterious dense objects from which no light can escape, with masses equivalent to more than 100,000 suns. There is a supermassive black hole in the center of nearly every galaxy, and it is called an active galactic nucleus (AGN) if it is gobbling up a lot of gas and dust from its surroundings. The brightest kind of AGN is called a quasar. While the black hole itself cannot be seen, its vicinity shines extremely brightly as matter gets torn apart close to its event horizon, its point of no return.

But black holes aren’t truly like vacuum cleaners; they don’t just suck up everything that gets too close. While some material around a black hole will fall directly in, never to be seen again, some of the nearby gas will be flung outward, creating a shell that expands over thousands of years. That’s because the area near the event horizon – the threshold around a black hole where the escape velocity surpasses the speed of light – is extremely energetic; the high-energy radiation from fast-moving particles around the black hole can eject a significant amount of gas into the vastness of space.

Scientists would expect that this outflow of gas would be smooth. Instead, it is clumpy, extending well beyond 1 parsec (3.3 light-years) from the black hole. Each cloud starts out small, but can expand to be more than 1 parsec wide – and could even cover the distance between Earth and the nearest star beyond the sun, Proxima Centauri.

Astrophysicist Daniel Proga at the University of Nevada, Las Vegas, likens these clumps to groups of cars waiting at a highway onramp with stoplights designed to regulate the influx of new traffic. He said:

Every now and then you have a bunch of cars.

What explains these clumps in deep space? Proga and colleagues have a new computer model that presents a possible solution to this mystery, published April 21, 2020, in the peer-reviewed Astrophysical Journal Letters. Science suggests that extremely intense heat near the supermassive black hole can allow the gas to flow outward really fast, but in a way that can also lead to clump formation. If the gas accelerates too quickly, it will not cool off enough to form clumps. The computer model takes these factors into account and proposes a mechanism to make the gas travel far, but also clump. Proga said:

Near the outer edge of the shell there is a perturbation that makes gas density a little bit lower than it used to be. That makes this gas heat up very efficiently. The cold gas further out is being lifted out by that.

This phenomenon is somewhat like the buoyancy that makes hot air balloons float. The heated air inside the balloon is lighter than the cooler air outside, and this density difference makes the balloon rise.

University of Nevada doctoral student Randall Dannen led the study. Dannen said:

This work is important because astronomers have always needed to place clouds at a given location and velocity to fit the observations we see from AGN. They were not often concerned with the specifics of how the clouds formed in the first place, and our work offers a potential explanation for the formation of these clouds.

This model looks only at the shell of gas, not at the disk of material swirling around the black hole that is feeding it. The researchers’ next step is to examine whether the flow of gas originates from the disk itself. They are also interested in tackling the mystery of why some clouds move extremely fast, on the order of 20 million miles per hour (10,000 kilometers per second).

Bottom line: A new study looks at how cosmic clouds form near black holes.

Source: Clumpy AGN Outflows due to Thermal Instability



from EarthSky https://ift.tt/2z2WWyV
Multicolored areas against black background and a fuzzy dark ring with a bright light shining from its center.

This artist’s concept depicts a quasar, a type of active galactic nucleus, surrounded by a dusty donut shape (torus) and clumps called “clouds.” These clouds start small but can expand to be more than 1 parsec (3.3 light-years) wide. In this diagram, the clouds are at least 1 parsec from the torus. Image via Nima Abkenar/ NASA.

Via NASA

Once you leave the majestic skies of Earth, the word cloud no longer means a white fluffy-looking structure that produces rain. Instead, clouds in the greater universe are clumpy areas of greater density than their surroundings.

Space telescopes have observed these cosmic clouds in the vicinity of supermassive black holes, those mysterious dense objects from which no light can escape, with masses equivalent to more than 100,000 suns. There is a supermassive black hole in the center of nearly every galaxy, and it is called an active galactic nucleus (AGN) if it is gobbling up a lot of gas and dust from its surroundings. The brightest kind of AGN is called a quasar. While the black hole itself cannot be seen, its vicinity shines extremely brightly as matter gets torn apart close to its event horizon, its point of no return.

But black holes aren’t truly like vacuum cleaners; they don’t just suck up everything that gets too close. While some material around a black hole will fall directly in, never to be seen again, some of the nearby gas will be flung outward, creating a shell that expands over thousands of years. That’s because the area near the event horizon – the threshold around a black hole where the escape velocity surpasses the speed of light – is extremely energetic; the high-energy radiation from fast-moving particles around the black hole can eject a significant amount of gas into the vastness of space.

Scientists would expect that this outflow of gas would be smooth. Instead, it is clumpy, extending well beyond 1 parsec (3.3 light-years) from the black hole. Each cloud starts out small, but can expand to be more than 1 parsec wide – and could even cover the distance between Earth and the nearest star beyond the sun, Proxima Centauri.

Astrophysicist Daniel Proga at the University of Nevada, Las Vegas, likens these clumps to groups of cars waiting at a highway onramp with stoplights designed to regulate the influx of new traffic. He said:

Every now and then you have a bunch of cars.

What explains these clumps in deep space? Proga and colleagues have a new computer model that presents a possible solution to this mystery, published April 21, 2020, in the peer-reviewed Astrophysical Journal Letters. Science suggests that extremely intense heat near the supermassive black hole can allow the gas to flow outward really fast, but in a way that can also lead to clump formation. If the gas accelerates too quickly, it will not cool off enough to form clumps. The computer model takes these factors into account and proposes a mechanism to make the gas travel far, but also clump. Proga said:

Near the outer edge of the shell there is a perturbation that makes gas density a little bit lower than it used to be. That makes this gas heat up very efficiently. The cold gas further out is being lifted out by that.

This phenomenon is somewhat like the buoyancy that makes hot air balloons float. The heated air inside the balloon is lighter than the cooler air outside, and this density difference makes the balloon rise.

University of Nevada doctoral student Randall Dannen led the study. Dannen said:

This work is important because astronomers have always needed to place clouds at a given location and velocity to fit the observations we see from AGN. They were not often concerned with the specifics of how the clouds formed in the first place, and our work offers a potential explanation for the formation of these clouds.

This model looks only at the shell of gas, not at the disk of material swirling around the black hole that is feeding it. The researchers’ next step is to examine whether the flow of gas originates from the disk itself. They are also interested in tackling the mystery of why some clouds move extremely fast, on the order of 20 million miles per hour (10,000 kilometers per second).

Bottom line: A new study looks at how cosmic clouds form near black holes.

Source: Clumpy AGN Outflows due to Thermal Instability



from EarthSky https://ift.tt/2z2WWyV

Seen from space: Covid-19 and the environment

As the Covid-19 pandemic has disrupted lives across the globe, Earth-observing satellites take the pulse of our planet from space. While the global lockdown has had a massive impact on daily life and the economy, there have been environmental benefits that are visible from space. How can we preserve these positives when returning to “business as usual”?

Via ESA



from EarthSky https://ift.tt/2zb8UGA

As the Covid-19 pandemic has disrupted lives across the globe, Earth-observing satellites take the pulse of our planet from space. While the global lockdown has had a massive impact on daily life and the economy, there have been environmental benefits that are visible from space. How can we preserve these positives when returning to “business as usual”?

Via ESA



from EarthSky https://ift.tt/2zb8UGA

Last Antarctic sunset

A group standing in snow, waving and posing, with the sun setting behind them.

May 3, 2020, sunset – the last sunset for several months – at Concordia research station in Antarctica. Image via ESA.

At Concordia Research Station in Antarctica, scientists are studying how an extreme environment can be a risk to the human body and mind. Their ultimate goal is preparing humans for life in outer space beyond low-Earth orbit. In early May, the sun set for winter at the facility. The photo above captured the scene. The European Space Agency (ESA) wrote:

The 16th crew at Concordia Research Station in Antarctica to spend a full winter at the facility, wave goodbye to the sun as it descends below the horizon, not to return for four months. May 3, 2020, marked the start of the crew’s winter-over period. The 12-member group will spend the next few months in total darkness. This is in addition to their nine-month isolation in one of the most extreme environments on Earth.

Concordia research station is one of three stations operating year round for science in the middle of the Antarctic ice sheet. Located at Dome C on the Antarctic peninsula, the station sits about 10,500 feet (3,200 meters) above sea level.

If the altitude does not steal your breath, the cold certainly will: temperatures can drop to -80°C (-112 F) in the winter, with a yearly average temperature of -50°C (-58 F).

Isolation in a cold, dark environment on Earth makes an ideal stand-in for space to better prepare us for exploration of our solar system. Researchers come to Concordia to study not only astronomy, meteorology and glaciology but also human physiology and psychology.

Researchers are interested in how this extreme environment can be a risk to the human body and mind. Data from these studies is preparing humans for life in outer space beyond low Earth orbit.

ESA-sponsored medical doctor Stijn Thoolen coordinates this year’s biomedical research experiments at Concordia to assess the prolonged effects of isolation on the human body and mind.

He collects blood, stool and urine samples to track changes in blood volume, immune system and gut bacteria and how they impact our health. Stijn also facilitates stress and coordination tests and follows social dynamics to understand the roles stress plays in making or breaking a group in isolation.

The coming months will prove the most challenging for the group but potentially also the most rewarding.

Follow the adventures at Concordia on the blog.

Bottom line: Photo showing the last sunset – prior to several months of winter darkness – at Concordia Research Station in Antarctica. Scientists at the station are studying how living in extreme conditions affects the human body and mind.

Via ESA



from EarthSky https://ift.tt/2yk8HR6
A group standing in snow, waving and posing, with the sun setting behind them.

May 3, 2020, sunset – the last sunset for several months – at Concordia research station in Antarctica. Image via ESA.

At Concordia Research Station in Antarctica, scientists are studying how an extreme environment can be a risk to the human body and mind. Their ultimate goal is preparing humans for life in outer space beyond low-Earth orbit. In early May, the sun set for winter at the facility. The photo above captured the scene. The European Space Agency (ESA) wrote:

The 16th crew at Concordia Research Station in Antarctica to spend a full winter at the facility, wave goodbye to the sun as it descends below the horizon, not to return for four months. May 3, 2020, marked the start of the crew’s winter-over period. The 12-member group will spend the next few months in total darkness. This is in addition to their nine-month isolation in one of the most extreme environments on Earth.

Concordia research station is one of three stations operating year round for science in the middle of the Antarctic ice sheet. Located at Dome C on the Antarctic peninsula, the station sits about 10,500 feet (3,200 meters) above sea level.

If the altitude does not steal your breath, the cold certainly will: temperatures can drop to -80°C (-112 F) in the winter, with a yearly average temperature of -50°C (-58 F).

Isolation in a cold, dark environment on Earth makes an ideal stand-in for space to better prepare us for exploration of our solar system. Researchers come to Concordia to study not only astronomy, meteorology and glaciology but also human physiology and psychology.

Researchers are interested in how this extreme environment can be a risk to the human body and mind. Data from these studies is preparing humans for life in outer space beyond low Earth orbit.

ESA-sponsored medical doctor Stijn Thoolen coordinates this year’s biomedical research experiments at Concordia to assess the prolonged effects of isolation on the human body and mind.

He collects blood, stool and urine samples to track changes in blood volume, immune system and gut bacteria and how they impact our health. Stijn also facilitates stress and coordination tests and follows social dynamics to understand the roles stress plays in making or breaking a group in isolation.

The coming months will prove the most challenging for the group but potentially also the most rewarding.

Follow the adventures at Concordia on the blog.

Bottom line: Photo showing the last sunset – prior to several months of winter darkness – at Concordia Research Station in Antarctica. Scientists at the station are studying how living in extreme conditions affects the human body and mind.

Via ESA



from EarthSky https://ift.tt/2yk8HR6

Find the Keystone in Hercules

EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store

Tonight, from mid-northern latitudes, you can easily find the brilliant star Vega in the eastern sky at dusk and nightfall. Vega acts as your guide star to the Keystone – a pattern of four stars in the constellation Hercules.

Look for the Keystone asterism – star pattern – to the upper right of the brilliant blue-white star Vega. Hold your fist at arm’s length. There is easily enough room between Vega and the Keystone for your fist to fit between the two.

You can also locate the Keystone by using Vega in conjunction with the brilliant yellow-orange star Arcturus. From mid-northern latitudes, Arcturus is found quite high in the southeast sky at nightfall and evening. By late evening, Arcturus will have moved over to the southern sky. The Keystone is found about one-third the way from Vega to Arcturus, the two brightest stars to grace the Northern Hemisphere’s spring and summertime sky. The only star-like object to outshine these stars is the king planet Jupiter, rather low in the southwest sky at nightfall.

Sky chart of the Keystone in Hercules with arrow to globular cluster M13.

Before you can find M13, you need to find the Keystone in Hercules, a pattern of four stars. As darkness falls, look for the Keystone to the upper right of the brilliant star Vega. Image via Wikimedia Commons.

The Keystone, in turn, is your ticket to finding a famous globular star cluster in Hercules, otherwise known as the Great Cluster in Hercules, aka Messier 13 or M13.

Most likely, you’ll need binoculars to see the Hercules cluster, although sharp-eyed people can see it with the unaided eye in a dark, transparent sky. Through binoculars, this cluster looks like a dim and somewhat hazy star. But a telescope begins to resolve this faint fuzzy into what it really is – a great big, globe-shaped stellar city populated with hundreds of thousands of stars!

The Keystone and the Hercules cluster swing high overhead after midnight, and are found in the western sky before dawn.

Sky chart of the constellation Hercules, black stars on white background.

View larger. | Can you find the Keystone on this chart? See the compact grouping of four stars at the center of Hercules? That’s it. Note the whereabouts of Messier 13 within the Keystone pattern.

Circular cluster of many stars fading to fewer around the edges.

The Great Cluster in Hercules – aka M13 – as captured by our friend Scott MacNeill at Frosty Drew Observatory in Charlestown, Rhode Island. Thanks, Scott!

Bottom line: Let the bright star Vega guide you to a famous star pattern in Hercules – called the Keystone – and then to the Great Cluster in Hercules, aka M13, a famous globular star cluster.

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



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EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store

Tonight, from mid-northern latitudes, you can easily find the brilliant star Vega in the eastern sky at dusk and nightfall. Vega acts as your guide star to the Keystone – a pattern of four stars in the constellation Hercules.

Look for the Keystone asterism – star pattern – to the upper right of the brilliant blue-white star Vega. Hold your fist at arm’s length. There is easily enough room between Vega and the Keystone for your fist to fit between the two.

You can also locate the Keystone by using Vega in conjunction with the brilliant yellow-orange star Arcturus. From mid-northern latitudes, Arcturus is found quite high in the southeast sky at nightfall and evening. By late evening, Arcturus will have moved over to the southern sky. The Keystone is found about one-third the way from Vega to Arcturus, the two brightest stars to grace the Northern Hemisphere’s spring and summertime sky. The only star-like object to outshine these stars is the king planet Jupiter, rather low in the southwest sky at nightfall.

Sky chart of the Keystone in Hercules with arrow to globular cluster M13.

Before you can find M13, you need to find the Keystone in Hercules, a pattern of four stars. As darkness falls, look for the Keystone to the upper right of the brilliant star Vega. Image via Wikimedia Commons.

The Keystone, in turn, is your ticket to finding a famous globular star cluster in Hercules, otherwise known as the Great Cluster in Hercules, aka Messier 13 or M13.

Most likely, you’ll need binoculars to see the Hercules cluster, although sharp-eyed people can see it with the unaided eye in a dark, transparent sky. Through binoculars, this cluster looks like a dim and somewhat hazy star. But a telescope begins to resolve this faint fuzzy into what it really is – a great big, globe-shaped stellar city populated with hundreds of thousands of stars!

The Keystone and the Hercules cluster swing high overhead after midnight, and are found in the western sky before dawn.

Sky chart of the constellation Hercules, black stars on white background.

View larger. | Can you find the Keystone on this chart? See the compact grouping of four stars at the center of Hercules? That’s it. Note the whereabouts of Messier 13 within the Keystone pattern.

Circular cluster of many stars fading to fewer around the edges.

The Great Cluster in Hercules – aka M13 – as captured by our friend Scott MacNeill at Frosty Drew Observatory in Charlestown, Rhode Island. Thanks, Scott!

Bottom line: Let the bright star Vega guide you to a famous star pattern in Hercules – called the Keystone – and then to the Great Cluster in Hercules, aka M13, a famous globular star cluster.

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



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Coronavirus reports – Part 3: “I should have known when they came back in PPE”

Charly and her daughter.

We caught up with people living with cancer across the country, to find out how the coronavirus pandemic has been affecting them and their families.

Christine: “I should have known when they came back in PPE”

Christine was diagnosed with ovarian cancer in September 2019. “I had some routine bloods done and I mentioned that I had some niggling pains in my side. Test results showed that something wasn’t right.” She was told by the doctor that the cancer was treatable, but not curable.

Christine had four rounds of chemotherapy before Christmas, followed by surgery in January. “I then had 6 weeks off before two more rounds of chemo.” It was after the second round that Christine started to feel unwell and was taken into hospital for tests.

Christine during treatment.

Christine during treatment.

It was pneumonia, sepsis and COVID-19.

“I should have known as they came in gowned up and in PPE when they came back.” Christine was isolated for 5 days at Salford Royal, and while the staff were amazing, the experience was not.

“I was so out of breath moving around the room. I was uncomfortable and it was not nice being stuck in the room. I couldn’t read or watch anything really, and I didn’t want to see any news.”

Not being able to have family also took its toll. “The doctors came in to tell me that if I needed intensive care, it would be up to the doctors in the unit whether I would be accepted for this. And I was hearing this all on my own – no family there.”

Fortunately, Christine didn’t need intensive care and was able to go home after 5 days. “I’m still not quite right and feel tired, but I am going out to walk the dog. I can’t give into this.”

Christine says that having family nearby has been so important. Her husband and son have been with her at home, while her other son lives nearby. “It’s a small family but so supportive. My husband is looking after me – we have been married 44 years.”

Charly: “COVID-19 has impacted my treatment options but has not stopped it, and for that I am grateful.”

Charly found a lump in her breast in February 2020. “It was the day before my daughter’s birthday, I had a shower and found a bit of a lump.”

She didn’t tell anyone in her family but scheduled an appointment with her GP, who referred her to the breast clinic. When she felt a lump in her armpit, she called to see if they could speed things up. “I was in a state of panic, I

Charly with her family.

Charly with her family.

was reading about everything.”

Her biopsy was in early March. “COVID-19 wasn’t really a concern at that point,” she says, but things changed rapidly over the next few weeks.

“I went back for the results on the 10th March and it was confirmed as having cancer. They said I would have chemo first, then radiotherapy and surgery.” Charly asked if the treatment plan might be affected by COVID-19, but the doctors didn’t know enough at that point.

But the situation evolved with the outbreak, with Charly’s appointment being followed by a flurry of calls. The doctors told Charly that because of COVID-19, chemo was off the table for now. “They said it was to be surgery first, and it should still be a lumpectomy. But by the time I went to meet the surgeon the week after, this changed to a full mastectomy.”

Charly says she had anticipated that changes may happen, and they quickly became a central part of her cancer experience. Her surgeon changed before the operation, which was particularly hard, especially as she was dealing with the changes by herself on the day.

“I had to go into surgery alone and that was one of the toughest things, but I just had to do it.”

And after 6 weeks recovering from surgery, which Charly describes as “an emotional and frustrating time”, it was time for chemo.

Because of COVID-19, Charly’s doctors changed the chemotherapy drugs to minimise infection risk. She started chemotherapy at the beginning of May, which will last 18 weeks in total. Charly says that being a personal trainer and an active person, the next stage could be the hardest for her. “I have always needed exercise for headspace, it is part of me.” It’s particularly hard not being able to run around with her kids.

The other big challenge for Charly has been the phone calls with her cancer team. “I am often on my own and there is so much information to take in. It’s hard to have a serious talk and build trust on the phone.”

“It’s such an emotionally charged time and it’s draining – COVID-19 has been a huge factor.”

But while her treatment has been complicated and challenging so far, Charly is positive. “I am lucky in many ways, my cancer is treatable and being ex-Army and a personal trainer I am relatively fit and healthy.”

Charly says that while lockdown with two young daughters – aged 4 and 5 – has been a challenge, there were some benefits during recovery. “Because of lockdown there were people around who were keen to help, with provisions or dog walking, so I felt less of a burden.”

Stephen: “Our dream family trip was cancelled due to COVID-19”

Stephen was diagnosed with stage 4 bowel cancer just before Christmas in 2019, after an accident brought him to the hospital.

Stephen with his daughter, Isabelle.

Stephen with his daughter, Isabelle.

The initial prognosis was that without chemotherapy, Stephen was expected to live for 6 to 9 months, and 12 to 18 months with it. “It’s incredibly daunting to be told those words, especially with a 10-month old baby. We had been looking forward to Isabelle’s first Christmas and then all this began.”

Stephen started a 6 month course of chemotherapy in January, and is responding well to the treatment so far. “If I continue to respond well, they may do a few operations on my liver and then re-assess everything else.”

A big thing that’s kept Stephen going through chemo was a family trip to Florida, which friends raised money for. “We would have liked to wait until Isabelle was older, but we thought we should go now, until that was cancelled due to COVID-19.” On the day the family was due to fly, Stephen was having chemo on his own instead.

Stephen says it’s been tough not being able to see loved ones, but they’ve celebrated Isabelle’s first birthday and his 30th in lockdown. “Having a positive mental attitude is vital, we’ve kept up the spirits.”

Katie

 

Thanks to Christine, Charly and Stephen for sharing their experiences. If you would like to share your story with us, please visit our website. And you can tell us how COVID-19 is impacting your life with cancer through our survey.

If you have questions about cancer, you can talk to our nurses Monday to Friday, 9-5pm, on freephone 0808 800 4040.



from Cancer Research UK – Science blog https://ift.tt/3fT9ZDo
Charly and her daughter.

We caught up with people living with cancer across the country, to find out how the coronavirus pandemic has been affecting them and their families.

Christine: “I should have known when they came back in PPE”

Christine was diagnosed with ovarian cancer in September 2019. “I had some routine bloods done and I mentioned that I had some niggling pains in my side. Test results showed that something wasn’t right.” She was told by the doctor that the cancer was treatable, but not curable.

Christine had four rounds of chemotherapy before Christmas, followed by surgery in January. “I then had 6 weeks off before two more rounds of chemo.” It was after the second round that Christine started to feel unwell and was taken into hospital for tests.

Christine during treatment.

Christine during treatment.

It was pneumonia, sepsis and COVID-19.

“I should have known as they came in gowned up and in PPE when they came back.” Christine was isolated for 5 days at Salford Royal, and while the staff were amazing, the experience was not.

“I was so out of breath moving around the room. I was uncomfortable and it was not nice being stuck in the room. I couldn’t read or watch anything really, and I didn’t want to see any news.”

Not being able to have family also took its toll. “The doctors came in to tell me that if I needed intensive care, it would be up to the doctors in the unit whether I would be accepted for this. And I was hearing this all on my own – no family there.”

Fortunately, Christine didn’t need intensive care and was able to go home after 5 days. “I’m still not quite right and feel tired, but I am going out to walk the dog. I can’t give into this.”

Christine says that having family nearby has been so important. Her husband and son have been with her at home, while her other son lives nearby. “It’s a small family but so supportive. My husband is looking after me – we have been married 44 years.”

Charly: “COVID-19 has impacted my treatment options but has not stopped it, and for that I am grateful.”

Charly found a lump in her breast in February 2020. “It was the day before my daughter’s birthday, I had a shower and found a bit of a lump.”

She didn’t tell anyone in her family but scheduled an appointment with her GP, who referred her to the breast clinic. When she felt a lump in her armpit, she called to see if they could speed things up. “I was in a state of panic, I

Charly with her family.

Charly with her family.

was reading about everything.”

Her biopsy was in early March. “COVID-19 wasn’t really a concern at that point,” she says, but things changed rapidly over the next few weeks.

“I went back for the results on the 10th March and it was confirmed as having cancer. They said I would have chemo first, then radiotherapy and surgery.” Charly asked if the treatment plan might be affected by COVID-19, but the doctors didn’t know enough at that point.

But the situation evolved with the outbreak, with Charly’s appointment being followed by a flurry of calls. The doctors told Charly that because of COVID-19, chemo was off the table for now. “They said it was to be surgery first, and it should still be a lumpectomy. But by the time I went to meet the surgeon the week after, this changed to a full mastectomy.”

Charly says she had anticipated that changes may happen, and they quickly became a central part of her cancer experience. Her surgeon changed before the operation, which was particularly hard, especially as she was dealing with the changes by herself on the day.

“I had to go into surgery alone and that was one of the toughest things, but I just had to do it.”

And after 6 weeks recovering from surgery, which Charly describes as “an emotional and frustrating time”, it was time for chemo.

Because of COVID-19, Charly’s doctors changed the chemotherapy drugs to minimise infection risk. She started chemotherapy at the beginning of May, which will last 18 weeks in total. Charly says that being a personal trainer and an active person, the next stage could be the hardest for her. “I have always needed exercise for headspace, it is part of me.” It’s particularly hard not being able to run around with her kids.

The other big challenge for Charly has been the phone calls with her cancer team. “I am often on my own and there is so much information to take in. It’s hard to have a serious talk and build trust on the phone.”

“It’s such an emotionally charged time and it’s draining – COVID-19 has been a huge factor.”

But while her treatment has been complicated and challenging so far, Charly is positive. “I am lucky in many ways, my cancer is treatable and being ex-Army and a personal trainer I am relatively fit and healthy.”

Charly says that while lockdown with two young daughters – aged 4 and 5 – has been a challenge, there were some benefits during recovery. “Because of lockdown there were people around who were keen to help, with provisions or dog walking, so I felt less of a burden.”

Stephen: “Our dream family trip was cancelled due to COVID-19”

Stephen was diagnosed with stage 4 bowel cancer just before Christmas in 2019, after an accident brought him to the hospital.

Stephen with his daughter, Isabelle.

Stephen with his daughter, Isabelle.

The initial prognosis was that without chemotherapy, Stephen was expected to live for 6 to 9 months, and 12 to 18 months with it. “It’s incredibly daunting to be told those words, especially with a 10-month old baby. We had been looking forward to Isabelle’s first Christmas and then all this began.”

Stephen started a 6 month course of chemotherapy in January, and is responding well to the treatment so far. “If I continue to respond well, they may do a few operations on my liver and then re-assess everything else.”

A big thing that’s kept Stephen going through chemo was a family trip to Florida, which friends raised money for. “We would have liked to wait until Isabelle was older, but we thought we should go now, until that was cancelled due to COVID-19.” On the day the family was due to fly, Stephen was having chemo on his own instead.

Stephen says it’s been tough not being able to see loved ones, but they’ve celebrated Isabelle’s first birthday and his 30th in lockdown. “Having a positive mental attitude is vital, we’ve kept up the spirits.”

Katie

 

Thanks to Christine, Charly and Stephen for sharing their experiences. If you would like to share your story with us, please visit our website. And you can tell us how COVID-19 is impacting your life with cancer through our survey.

If you have questions about cancer, you can talk to our nurses Monday to Friday, 9-5pm, on freephone 0808 800 4040.



from Cancer Research UK – Science blog https://ift.tt/3fT9ZDo

More evidence for watery plumes on Europa

Bright geyser-like vertical spray of water with planet and stars in background.

Artist’s concept of water vapor plumes on Europa, the smallest of Jupiter’s 4 large Galilean moons. Image via ASA/ ESA/ K. Retherford/ SwRI/ Science.

The huge plumes of water vapor erupting through enormous cracks in the surface of Saturn’s moon Enceladus were quickly found by the Cassini spacecraft after it began orbiting Saturn in 2004. They’re thought to arise from a salty global ocean below the moon’s ice crust. Over the past few years, evidence has been accumulating for watery plumes on Jupiter’s large ocean moon Europa, too. It’s taking longer to put the pieces of the puzzle together, but – although still not definitive – the data for plumes on Europa are beginning to look compelling. They indicate that geyser-like plumes erupt from Europa’s surface, at least occasionally. On May 12, 2020, researchers at the Max Planck Institute for Solar System Research (MPS) in Germany and the European Space Agency (ESA) reported yet more evidence for water plumes on Europa.

The new work supports previous studies that suggested that – although it wasn’t recognized at the time – NASA’s Galileo spacecraft glimpsed one of these plumes during a flyby of Europa in 2000. The researchers published their work in Geophysical Research Letters in late April.

Making the case for plumes on Europa has been a long process, since, from the evidence gathered so far, they are seemingly intermittent. In contrast, the plumes on Enceladus were large and easy to see and, at least at the time, were erupting continuously. MPS scientist Elias Roussos said in a statement:

 However, various theories, models, and sporadic observations suggest that Europa, too, can exhibit plumes.

Smooth whitish globe covered in brown cracks, on black background.

Jupiter’s ocean moon Europa, as seen by Galileo. This image is a combination of images from 1995 and 1998. Scientists have found yet more evidence for water vapor plumes erupting from its icy surface, most likely originating in the ocean below. Image via NASA/ JPL-Caltech/ SETI Institute.

How did the researchers find further evidence for Europa’s plumes?

They used computer simulations to replicate the data from the Energetic Particles Detector (EPD) onboard Galileo during a flyby of Europa in 2000. EPD recorded the distribution of high-energy protons trapped in Jupiter’s powerful magnetic field, which is 20 times stronger than Earth’s. Europa orbits within that magnetic field. Back in 2000, the detector recorded fewer protons during the flyby than had been expected. At the time, it was thought that Europa itself was blocking the view of the detector.

But now the new study suggests something else. The researchers modeled the movements of protons during the flyby, in an attempt to reproduce the original results from Galileo. But – surprise – they found that the only model that matched the results was one where a water vapor plume was between Europa and the detector.

Two globes on dark blue mottled background each with a tiny white bulge on the edge labeled Plume.

Composite photos from the Hubble Space Telescope and the Galileo spacecraft, showing a suspected plume erupting in the same place on Europa in 2014 and 2016. Image via NASA/ ESA/ W. Sparks (STScI)/ USGS Astrogeology Science Center/ JPL-Caltech.

The plume would have disrupted both Europa’s extremely thin atmosphere and the magnetic field. This also would have changed the amount and behavior of the energetic protons. When the protons collided with uncharged particles from Europa’s atmosphere or plume, they took electrons from them, becoming uncharged particles themselves. As Hans Huybrighs from ESA, lead author of the new study, said:

This means they are no longer trapped in Jupiter’s magnetic field and can leave the system at high speed.

Therefore, the decreased number of protons detected during the flyby could be explained by a water vapor plume.

Last year, it was reported that water vapor itself had been directly detected above Europa’s surface by researchers using the W. M. Keck Observatory on Mauna Kea in Hawaii. According to NASA scientist Lucas Paganini:

Essential chemical elements (carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur) and sources of energy, two of three requirements for life, are found all over the solar system. But the third – liquid water – is somewhat hard to find beyond Earth. While scientists have not yet detected liquid water directly, we’ve found the next best thing: water in vapor form.

The water vapor signal was faint, however, and only seen once in 17 nights of observations in 2016 and 2017. The Hubble Space Telescope (HST) also took images in 2014 and 2016 that appear to show a plume in the same location. But even that wasn’t considered quite conclusive enough.

Partial view of globe with bright streaks coming out of it, on black background.

Saturn’s moon Enceladus was confirmed to have water vapor plumes by the Cassini spacecraft. This stunning photo shows then erupting through cracks in the ice crust at the moon’s south pole. Evidence suggests they are more active than those on Europa. Image via NASA Science.

Based on this and previous studies, the Europan plumes are probably less frequent and maybe smaller than those on Enceladus. But that doesn’t make them any less exciting. If they occur in a manner similar to the ones on Enceladus, then they probably originate from the subsurface ocean. Both Europa and Enceladus are now known to have global oceans below their outer ice crusts.

Cassini was able to sample the plumes at Enceladus, and found water vapor, methane, salts and organic molecules. It also found evidence for current active hydrothermal vents – just like in Earth’s oceans – on the ocean floor of Enceladus. The organics by themselves don’t prove yet there is life there, but combined with the hydrothermal clues, they point to a likely habitable environment in Enceladus’ ocean. Is the same true for Europa?

The Juno probe currently orbiting Jupiter isn’t able to conduct flybys of Europa, but NASA’s upcoming Europa Clipper mission, scheduled to launch in 2023, will make many such flybys. If the exact locations of any plumes can be determined beforehand, then Europa Clipper should be able to fly right through them, just like Cassini did at Enceladus. The composition could then be determined, and thus scientists could learn more about conditions in the ocean itself. ESA’s Jupiter Icy Moon Explorer (JUICE) mission to Jupiter, launching in 2022, will also be able to study Europa in more detail.

Although Europa is slightly smaller than our moon, its global subsurface ocean is estimated to contain more water than all the oceans on Earth combined. If there is any hydrothermal activity on the ocean bottom, as on Earth and Enceladus, that would increase the chances of the ocean being habitable, despite being completely hidden from sunlight by the ice crust. Even in deep oceans on Earth, a wide variety of life thrives around hot hydrothermal vents, with no sunlight needed.

Smiling man in blue shirt standing in front of glass windows.

Hans Huybrighs at ESA, lead author of the new study. Image via ESA.

The evidence for plumes on Europa seems stronger than ever, but absolute certainty may have to wait for either the Europa Clipper or JUICE mission. Confirmation would be exciting, allowing scientists a way to sample and analyze water coming from the ocean without having to drill through the ice (still a long way off), just like at Enceladus. And then, just maybe, we will be much closer to to answering the biggest question of all: is there life on Europa?

Bottom line: Scientists in Europe have found more evidence for water vapor plumes on Europa.

Source: An Active Plume Eruption on Europa During Galileo Flyby E26 as Indicated by Energetic Proton Depletions

Via MPS

Via ESA



from EarthSky https://ift.tt/2WHqkn3
Bright geyser-like vertical spray of water with planet and stars in background.

Artist’s concept of water vapor plumes on Europa, the smallest of Jupiter’s 4 large Galilean moons. Image via ASA/ ESA/ K. Retherford/ SwRI/ Science.

The huge plumes of water vapor erupting through enormous cracks in the surface of Saturn’s moon Enceladus were quickly found by the Cassini spacecraft after it began orbiting Saturn in 2004. They’re thought to arise from a salty global ocean below the moon’s ice crust. Over the past few years, evidence has been accumulating for watery plumes on Jupiter’s large ocean moon Europa, too. It’s taking longer to put the pieces of the puzzle together, but – although still not definitive – the data for plumes on Europa are beginning to look compelling. They indicate that geyser-like plumes erupt from Europa’s surface, at least occasionally. On May 12, 2020, researchers at the Max Planck Institute for Solar System Research (MPS) in Germany and the European Space Agency (ESA) reported yet more evidence for water plumes on Europa.

The new work supports previous studies that suggested that – although it wasn’t recognized at the time – NASA’s Galileo spacecraft glimpsed one of these plumes during a flyby of Europa in 2000. The researchers published their work in Geophysical Research Letters in late April.

Making the case for plumes on Europa has been a long process, since, from the evidence gathered so far, they are seemingly intermittent. In contrast, the plumes on Enceladus were large and easy to see and, at least at the time, were erupting continuously. MPS scientist Elias Roussos said in a statement:

 However, various theories, models, and sporadic observations suggest that Europa, too, can exhibit plumes.

Smooth whitish globe covered in brown cracks, on black background.

Jupiter’s ocean moon Europa, as seen by Galileo. This image is a combination of images from 1995 and 1998. Scientists have found yet more evidence for water vapor plumes erupting from its icy surface, most likely originating in the ocean below. Image via NASA/ JPL-Caltech/ SETI Institute.

How did the researchers find further evidence for Europa’s plumes?

They used computer simulations to replicate the data from the Energetic Particles Detector (EPD) onboard Galileo during a flyby of Europa in 2000. EPD recorded the distribution of high-energy protons trapped in Jupiter’s powerful magnetic field, which is 20 times stronger than Earth’s. Europa orbits within that magnetic field. Back in 2000, the detector recorded fewer protons during the flyby than had been expected. At the time, it was thought that Europa itself was blocking the view of the detector.

But now the new study suggests something else. The researchers modeled the movements of protons during the flyby, in an attempt to reproduce the original results from Galileo. But – surprise – they found that the only model that matched the results was one where a water vapor plume was between Europa and the detector.

Two globes on dark blue mottled background each with a tiny white bulge on the edge labeled Plume.

Composite photos from the Hubble Space Telescope and the Galileo spacecraft, showing a suspected plume erupting in the same place on Europa in 2014 and 2016. Image via NASA/ ESA/ W. Sparks (STScI)/ USGS Astrogeology Science Center/ JPL-Caltech.

The plume would have disrupted both Europa’s extremely thin atmosphere and the magnetic field. This also would have changed the amount and behavior of the energetic protons. When the protons collided with uncharged particles from Europa’s atmosphere or plume, they took electrons from them, becoming uncharged particles themselves. As Hans Huybrighs from ESA, lead author of the new study, said:

This means they are no longer trapped in Jupiter’s magnetic field and can leave the system at high speed.

Therefore, the decreased number of protons detected during the flyby could be explained by a water vapor plume.

Last year, it was reported that water vapor itself had been directly detected above Europa’s surface by researchers using the W. M. Keck Observatory on Mauna Kea in Hawaii. According to NASA scientist Lucas Paganini:

Essential chemical elements (carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur) and sources of energy, two of three requirements for life, are found all over the solar system. But the third – liquid water – is somewhat hard to find beyond Earth. While scientists have not yet detected liquid water directly, we’ve found the next best thing: water in vapor form.

The water vapor signal was faint, however, and only seen once in 17 nights of observations in 2016 and 2017. The Hubble Space Telescope (HST) also took images in 2014 and 2016 that appear to show a plume in the same location. But even that wasn’t considered quite conclusive enough.

Partial view of globe with bright streaks coming out of it, on black background.

Saturn’s moon Enceladus was confirmed to have water vapor plumes by the Cassini spacecraft. This stunning photo shows then erupting through cracks in the ice crust at the moon’s south pole. Evidence suggests they are more active than those on Europa. Image via NASA Science.

Based on this and previous studies, the Europan plumes are probably less frequent and maybe smaller than those on Enceladus. But that doesn’t make them any less exciting. If they occur in a manner similar to the ones on Enceladus, then they probably originate from the subsurface ocean. Both Europa and Enceladus are now known to have global oceans below their outer ice crusts.

Cassini was able to sample the plumes at Enceladus, and found water vapor, methane, salts and organic molecules. It also found evidence for current active hydrothermal vents – just like in Earth’s oceans – on the ocean floor of Enceladus. The organics by themselves don’t prove yet there is life there, but combined with the hydrothermal clues, they point to a likely habitable environment in Enceladus’ ocean. Is the same true for Europa?

The Juno probe currently orbiting Jupiter isn’t able to conduct flybys of Europa, but NASA’s upcoming Europa Clipper mission, scheduled to launch in 2023, will make many such flybys. If the exact locations of any plumes can be determined beforehand, then Europa Clipper should be able to fly right through them, just like Cassini did at Enceladus. The composition could then be determined, and thus scientists could learn more about conditions in the ocean itself. ESA’s Jupiter Icy Moon Explorer (JUICE) mission to Jupiter, launching in 2022, will also be able to study Europa in more detail.

Although Europa is slightly smaller than our moon, its global subsurface ocean is estimated to contain more water than all the oceans on Earth combined. If there is any hydrothermal activity on the ocean bottom, as on Earth and Enceladus, that would increase the chances of the ocean being habitable, despite being completely hidden from sunlight by the ice crust. Even in deep oceans on Earth, a wide variety of life thrives around hot hydrothermal vents, with no sunlight needed.

Smiling man in blue shirt standing in front of glass windows.

Hans Huybrighs at ESA, lead author of the new study. Image via ESA.

The evidence for plumes on Europa seems stronger than ever, but absolute certainty may have to wait for either the Europa Clipper or JUICE mission. Confirmation would be exciting, allowing scientists a way to sample and analyze water coming from the ocean without having to drill through the ice (still a long way off), just like at Enceladus. And then, just maybe, we will be much closer to to answering the biggest question of all: is there life on Europa?

Bottom line: Scientists in Europe have found more evidence for water vapor plumes on Europa.

Source: An Active Plume Eruption on Europa During Galileo Flyby E26 as Indicated by Energetic Proton Depletions

Via MPS

Via ESA



from EarthSky https://ift.tt/2WHqkn3

Learn to recognize the wildlife out your window

A small, furry, bushy-tailed squirrel standing in short grass

Is it a single busy squirrel you’re watching every day? Or is it a cast of characters? Image via Julian Avery/ The Conversation.

By Julian Avery, Pennsylvania State University

Watching the wildlife outside your window can boost your mental well-being, and it’s something lots of people have been doing a lot more of lately.

Maybe you’ve been wondering if you’re seeing one persistent gray squirrel or a rotating cast of furry characters. Maybe you’ve been thinking about which birds are passing through for the season and which are townies who stick around all year.

As a wildlife ecologist, I’ve learned to pay attention to patterns that show me what the animals outside my window are up to, and I usually know which individuals are my regulars.

Whether you’re spying on animals in a city, town or rural area, with a little background knowledge, you too can keep tabs on the private lives of your neighborhood critters.

Seasonal shifts change the players

For many species, winter is a time when individuals compete less with one another and gather in large groups.

For example, eastern cottontail rabbits congregate around areas with plenty of food and places to escape to. Birds form large mixed-species flocks, which helps them better find food and avoid being hunted. They even form temporary allegiances as they forage together, following specific individuals who help determine where the flock goes.

Animated map of U.S. and Canada showing areas where birds are across a years time.

Seasonal migration means the abundance of particular species in one location can change over the course of the year. Image courtesy eBird.org

As the season changes to spring, migratory species start arriving. A steady parade of individuals moves through the neighborhood. As animals transition to their breeding season, plumage and appearances may change as they work to attract mates. For many species, defense of a piece of land becomes an overriding concern.

During the summer months, adult animal numbers stabilize, and the drive to establish a territory means you’re likely to have the same individuals active outside your windows for the majority of summer.

Bird on the grass, brown and gray with black, white, and yellow markings.

This white-throated sparrow is molting into breeding plumage before heading on to summer grounds. Image via Julian Avery/ The Conversation.

Splitting up the neighborhood

A territory is a chunk of habitat. Its size will vary depending on the amount of food and breeding resources it holds. A territory with few trees, for example, may need to be bigger to hold enough forage for the animal that owns the turf.

Territory sizes for different species can range from the size of a large kitchen table (common lizards like green anoles and skinks) to an area greater than 120 football fields (a raptor such as the Cooper’s hawk). The cool thing is that animal home ranges are governed by their own needs and often do not follow the lines of human fences and alleyways.

Overlapping transparent blobs of color.

A territory map for anoles shows how these lizards each have their own home turf that can overlap with neighbors. Habitat in this case included individual trees and a fallen log toward the bottom of the map which offered basking and display space Image via Jordan Bush.

I like to think of animal territories as quilts that drape over your neighborhood. For some species, like anoles, the squares in that quilt will have many small and intricate pieces, and you could fit many quilt pieces within each individual human property boundary. Some of those pieces will even overlap other patches.

Small songbirds will have quilt patches that span several human properties, though they may use specific parts more than others. Larger species will have quilt patches that cover entire neighborhoods with one territory.

Frequently spotted

If you’ve become familiar with the animals in your neighborhood, chances are you’ll see some of the same individuals again year after year. Eastern cottontails are likely to live up to three years in the wild, and they stay in the same general territory throughout their lives. Even the young have a tendency to stay close to their birth place.

Researchers have recaptured gray squirrels year after year in their original territories. On average, these critters survive about six years and can live longer than 20.

Birds also have long lives and will often stay in the same territory year after year. However, when eggs don’t hatch or young die in the nest, some birds may choose a new territory the following year. This means there can be high turnover in your local bird network if the local habitat is unpredictable or full of urban predators.

Birds that don’t migrate and stay in residence year-round, like chickadees, often have a tendency to stay in the same area, which means you’ll be seeing the same individual birds outside your window across seasons.

Some species will have territories that don’t overlap much at all. For others, the overlap can be extensive.

This means that generally during the breeding season, you could be watching many gray squirrels visiting outside your window.

There may also be a couple of male cottontails, but probably a single female because they tend to not overlap with other females.

Maybe you’ll spy the same pair of cardinals along with a reliable pair of chickadees. If you’re watching closely like I was the other day, you may get lucky and catch another male cardinal from the territory next door trying to flirt with your female, at least until her mate realizes what’s about to happen. That is a clue to the invisible lines birds have drawn between their own domains.

Green anole head peeking from edge of photo on orange backgtound.

Plenty of anole territories can fit into one human-scaled backyard. Image via Julian Avery

When it comes to smaller animals, like lizards and insects, all bets are off for how many unique individuals are present outside your window. But you can expect more of everything as the number of native plants increases.

Tips for watching

If you’re interested in trying to keep track of particular wildlife friends through the window, try to watch for identifying marks.

Squirrel with notched ear eating something.

Natural markings like a torn ear can help you keep track of individuals. Image via Julian Avery.

In my research, I attach colored bands to bird legs or mark the scales of turtles and snakes so we can figure out how many exist in an area. Many animals have enough individual variation that you can keep track of them using their natural unique marks and scars. Squirrels can have torn ears or injured tails, lizards can have unique scars or healed injuries, and birds can have subtle differences in color or pattern.

Also try paying attention to the maximum number you see at any one point. Where do they go after eating or basking? You may get lucky and spy a nest or resting place. See if you can spot other individuals coming from different directions and territories.

Baby rabbit crouching in short grass.

Maybe you’ll notice animal families expanding. Image via Julian Avery.

At my house, we had a nest of rabbit kits born under our deck. I thought there was only one surviving newborn because we never saw more than one offspring. Two weeks later, there were three babies foraging simultaneously in the yard, and it became clear that they’d previously been taking turns coming out of hiding.

If you start watching closely, I think you’ll find so much drama happening in your neighborhood that you may get hooked on the action.

Julian Avery, Assistant Research Professor of Wildlife Ecology and Conservation, Pennsylvania State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Bottom line: Tips to recognizing individual birds, squirrels, and other wildlife out your window.

The Conversation



from EarthSky https://ift.tt/3bAQgVO
A small, furry, bushy-tailed squirrel standing in short grass

Is it a single busy squirrel you’re watching every day? Or is it a cast of characters? Image via Julian Avery/ The Conversation.

By Julian Avery, Pennsylvania State University

Watching the wildlife outside your window can boost your mental well-being, and it’s something lots of people have been doing a lot more of lately.

Maybe you’ve been wondering if you’re seeing one persistent gray squirrel or a rotating cast of furry characters. Maybe you’ve been thinking about which birds are passing through for the season and which are townies who stick around all year.

As a wildlife ecologist, I’ve learned to pay attention to patterns that show me what the animals outside my window are up to, and I usually know which individuals are my regulars.

Whether you’re spying on animals in a city, town or rural area, with a little background knowledge, you too can keep tabs on the private lives of your neighborhood critters.

Seasonal shifts change the players

For many species, winter is a time when individuals compete less with one another and gather in large groups.

For example, eastern cottontail rabbits congregate around areas with plenty of food and places to escape to. Birds form large mixed-species flocks, which helps them better find food and avoid being hunted. They even form temporary allegiances as they forage together, following specific individuals who help determine where the flock goes.

Animated map of U.S. and Canada showing areas where birds are across a years time.

Seasonal migration means the abundance of particular species in one location can change over the course of the year. Image courtesy eBird.org

As the season changes to spring, migratory species start arriving. A steady parade of individuals moves through the neighborhood. As animals transition to their breeding season, plumage and appearances may change as they work to attract mates. For many species, defense of a piece of land becomes an overriding concern.

During the summer months, adult animal numbers stabilize, and the drive to establish a territory means you’re likely to have the same individuals active outside your windows for the majority of summer.

Bird on the grass, brown and gray with black, white, and yellow markings.

This white-throated sparrow is molting into breeding plumage before heading on to summer grounds. Image via Julian Avery/ The Conversation.

Splitting up the neighborhood

A territory is a chunk of habitat. Its size will vary depending on the amount of food and breeding resources it holds. A territory with few trees, for example, may need to be bigger to hold enough forage for the animal that owns the turf.

Territory sizes for different species can range from the size of a large kitchen table (common lizards like green anoles and skinks) to an area greater than 120 football fields (a raptor such as the Cooper’s hawk). The cool thing is that animal home ranges are governed by their own needs and often do not follow the lines of human fences and alleyways.

Overlapping transparent blobs of color.

A territory map for anoles shows how these lizards each have their own home turf that can overlap with neighbors. Habitat in this case included individual trees and a fallen log toward the bottom of the map which offered basking and display space Image via Jordan Bush.

I like to think of animal territories as quilts that drape over your neighborhood. For some species, like anoles, the squares in that quilt will have many small and intricate pieces, and you could fit many quilt pieces within each individual human property boundary. Some of those pieces will even overlap other patches.

Small songbirds will have quilt patches that span several human properties, though they may use specific parts more than others. Larger species will have quilt patches that cover entire neighborhoods with one territory.

Frequently spotted

If you’ve become familiar with the animals in your neighborhood, chances are you’ll see some of the same individuals again year after year. Eastern cottontails are likely to live up to three years in the wild, and they stay in the same general territory throughout their lives. Even the young have a tendency to stay close to their birth place.

Researchers have recaptured gray squirrels year after year in their original territories. On average, these critters survive about six years and can live longer than 20.

Birds also have long lives and will often stay in the same territory year after year. However, when eggs don’t hatch or young die in the nest, some birds may choose a new territory the following year. This means there can be high turnover in your local bird network if the local habitat is unpredictable or full of urban predators.

Birds that don’t migrate and stay in residence year-round, like chickadees, often have a tendency to stay in the same area, which means you’ll be seeing the same individual birds outside your window across seasons.

Some species will have territories that don’t overlap much at all. For others, the overlap can be extensive.

This means that generally during the breeding season, you could be watching many gray squirrels visiting outside your window.

There may also be a couple of male cottontails, but probably a single female because they tend to not overlap with other females.

Maybe you’ll spy the same pair of cardinals along with a reliable pair of chickadees. If you’re watching closely like I was the other day, you may get lucky and catch another male cardinal from the territory next door trying to flirt with your female, at least until her mate realizes what’s about to happen. That is a clue to the invisible lines birds have drawn between their own domains.

Green anole head peeking from edge of photo on orange backgtound.

Plenty of anole territories can fit into one human-scaled backyard. Image via Julian Avery

When it comes to smaller animals, like lizards and insects, all bets are off for how many unique individuals are present outside your window. But you can expect more of everything as the number of native plants increases.

Tips for watching

If you’re interested in trying to keep track of particular wildlife friends through the window, try to watch for identifying marks.

Squirrel with notched ear eating something.

Natural markings like a torn ear can help you keep track of individuals. Image via Julian Avery.

In my research, I attach colored bands to bird legs or mark the scales of turtles and snakes so we can figure out how many exist in an area. Many animals have enough individual variation that you can keep track of them using their natural unique marks and scars. Squirrels can have torn ears or injured tails, lizards can have unique scars or healed injuries, and birds can have subtle differences in color or pattern.

Also try paying attention to the maximum number you see at any one point. Where do they go after eating or basking? You may get lucky and spy a nest or resting place. See if you can spot other individuals coming from different directions and territories.

Baby rabbit crouching in short grass.

Maybe you’ll notice animal families expanding. Image via Julian Avery.

At my house, we had a nest of rabbit kits born under our deck. I thought there was only one surviving newborn because we never saw more than one offspring. Two weeks later, there were three babies foraging simultaneously in the yard, and it became clear that they’d previously been taking turns coming out of hiding.

If you start watching closely, I think you’ll find so much drama happening in your neighborhood that you may get hooked on the action.

Julian Avery, Assistant Research Professor of Wildlife Ecology and Conservation, Pennsylvania State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Bottom line: Tips to recognizing individual birds, squirrels, and other wildlife out your window.

The Conversation



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