LIGO and Virgo find a mystery object in the “mass gap”

In August of 2019, the LIGO-Virgo gravitational-wave network witnessed the merger of a black hole with 23 times the mass of our sun and a mystery object 2.6 times the mass of the sun. Scientists do not know if the mystery object was a neutron star or black hole, but either way it set a record as being either the heaviest-known neutron star … or the lightest-known black hole. Image via LIGO/ Caltech/ MIT/ R. Hurt (IPAC).

Originally published June 23, 2020 by the international LIGO-Virgo collaboration.

When the most massive stars die, they collapse under their own gravity and leave behind black holes; when stars that are a bit less massive die, they explode in supernovas and leave behind dense, dead remnants of stars called neutron stars. For decades, astronomers have been puzzled by a gap that lies between neutron stars and black holes: the heaviest known neutron star is no more than 2.5 times the mass of our Sun, or 2.5 solar masses, and the lightest known black hole is about 5 solar masses. The question remained: does anything lie in this so-called mass gap?

Now, in a new study from the National Science Foundation’s Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo detector in Europe, scientists have announced the discovery of an object of 2.6 solar masses, placing it firmly in the mass gap. The object was found on August 14, 2019, as it merged with a black hole of 23 solar masses, generating a splash of gravitational waves detected back on Earth by LIGO and Virgo. A paper about the detection is being published today, June 23, in The Astrophysical Journal Letters.

“We’ve been waiting decades to solve this mystery” says Vicky Kalogera, a professor at Northwestern University. “We don’t know if this object is the heaviest known neutron star, or the lightest known black hole, but either way it breaks a record.”

“This is going to change how scientists talk about neutron stars and black holes,” says co-author Patrick Brady, a professor at the University of Wisconsin, Milwaukee, and the LIGO Scientific Collaboration spokesperson. “The mass gap may in fact not exist at all but may have been due to limitations in observational capabilities. Time and more observations will tell.”

The cosmic merger described in the study, an event dubbed GW190814, resulted in a final black hole about 25 times the mass of the Sun (some of the merged mass was converted to a blast of energy in the form of gravitational waves). The newly formed black hole lies about 800 million light-years away from Earth.

Before the two objects merged, their masses differed by a factor of 9, making this the most extreme mass ratio known for a gravitational-wave event. Another recently reported LIGO-Virgo event, called GW190412, occurred between two black holes with a mass ratio of about 4:1.

“It’s a challenge for current theoretical models to form merging pairs of compact objects with such a large mass ratio in which the low-mass partner resides in the mass gap. This discovery implies these events occur much more often than we predicted, making this a really intriguing low-mass object,” explains Kalogera. “The mystery object may be a neutron star merging with a black hole, an exciting possibility expected theoretically but not yet confirmed observationally. However, at 2.6 times the mass of our Sun, it exceeds modern predictions for the maximum mass of neutron stars, and may instead be the lightest black hole ever detected.”

When the LIGO and Virgo scientists spotted this merger, they immediately sent out an alert to the astronomical community. Dozens of ground- and space-based telescopes followed up in search of light waves generated in the event, but none picked up any signals. So far, such light counterparts to gravitational-wave signals have been seen only once, in an event called GW170817. That event, discovered by the LIGO-Virgo network in August of 2017, involved a fiery collision between two neutron stars that was subsequently witnessed by dozens of telescopes on Earth and in space. Neutron star collisions are messy affairs with matter flung outward in all directions and are thus expected to shine with light. Conversely, black hole mergers, in most circumstances, are thought not to produce light.

According to the LIGO and Virgo scientists, the August 2019 event was not seen by light-based telescopes for a few possible reasons. First, this event was six times farther away than the merger observed in 2017, making it harder to pick up any light signals. Secondly, if the collision involved two black holes, it likely would have not shone with any light. Thirdly, if the object was in fact a neutron star, its 9-fold more massive black-hole partner might have swallowed it whole; a neutron star consumed whole by a black hole would not give off any light.

“I think of Pac-Man eating a little dot,” says Kalogera. “When the masses are highly asymmetric, the smaller neutron star can be eaten in one bite.”

How will researchers ever know if the mystery object was a neutron star or a black hole? Future observations with LIGO, Virgo, and possibly other telescopes may catch similar events that would help reveal whether additional objects exist in the mass gap.

“This is the first glimpse of what could be a whole new population of compact binary objects,” says Charlie Hoy, a member of the LIGO Scientific Collaboration and a graduate student at Cardiff University. “What is really exciting is that this is just the start. As the detectors get more and more sensitive, we will observe even more of these signals, and we will be able to pinpoint the populations of neutron stars and black holes in the universe.”

“The mass gap has been an interesting puzzle for decades, and now we’ve detected an object that fits just inside it,” says Pedro Marronetti, program director for gravitational physics at the National Science Foundation (NSF). “That cannot be explained without defying our understanding of extremely dense matter or what we know about the evolution of stars. This observation is yet another example of the transformative potential of the field of gravitational-wave astronomy, which brings novel insights with every new detection.”

Bottom line:

Source: GW190814: Gravitational Waves from the Coalescence of a 23 Solar Mass Black Hole with a 2.6 Solar Mass Compact Object

Via LIGO/ Caltech

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

In August of 2019, the LIGO-Virgo gravitational-wave network witnessed the merger of a black hole with 23 times the mass of our sun and a mystery object 2.6 times the mass of the sun. Scientists do not know if the mystery object was a neutron star or black hole, but either way it set a record as being either the heaviest-known neutron star … or the lightest-known black hole. Image via LIGO/ Caltech/ MIT/ R. Hurt (IPAC).

Originally published June 23, 2020 by the international LIGO-Virgo collaboration.

When the most massive stars die, they collapse under their own gravity and leave behind black holes; when stars that are a bit less massive die, they explode in supernovas and leave behind dense, dead remnants of stars called neutron stars. For decades, astronomers have been puzzled by a gap that lies between neutron stars and black holes: the heaviest known neutron star is no more than 2.5 times the mass of our Sun, or 2.5 solar masses, and the lightest known black hole is about 5 solar masses. The question remained: does anything lie in this so-called mass gap?

Now, in a new study from the National Science Foundation’s Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo detector in Europe, scientists have announced the discovery of an object of 2.6 solar masses, placing it firmly in the mass gap. The object was found on August 14, 2019, as it merged with a black hole of 23 solar masses, generating a splash of gravitational waves detected back on Earth by LIGO and Virgo. A paper about the detection is being published today, June 23, in The Astrophysical Journal Letters.

“We’ve been waiting decades to solve this mystery” says Vicky Kalogera, a professor at Northwestern University. “We don’t know if this object is the heaviest known neutron star, or the lightest known black hole, but either way it breaks a record.”

“This is going to change how scientists talk about neutron stars and black holes,” says co-author Patrick Brady, a professor at the University of Wisconsin, Milwaukee, and the LIGO Scientific Collaboration spokesperson. “The mass gap may in fact not exist at all but may have been due to limitations in observational capabilities. Time and more observations will tell.”

The cosmic merger described in the study, an event dubbed GW190814, resulted in a final black hole about 25 times the mass of the Sun (some of the merged mass was converted to a blast of energy in the form of gravitational waves). The newly formed black hole lies about 800 million light-years away from Earth.

Before the two objects merged, their masses differed by a factor of 9, making this the most extreme mass ratio known for a gravitational-wave event. Another recently reported LIGO-Virgo event, called GW190412, occurred between two black holes with a mass ratio of about 4:1.

“It’s a challenge for current theoretical models to form merging pairs of compact objects with such a large mass ratio in which the low-mass partner resides in the mass gap. This discovery implies these events occur much more often than we predicted, making this a really intriguing low-mass object,” explains Kalogera. “The mystery object may be a neutron star merging with a black hole, an exciting possibility expected theoretically but not yet confirmed observationally. However, at 2.6 times the mass of our Sun, it exceeds modern predictions for the maximum mass of neutron stars, and may instead be the lightest black hole ever detected.”

When the LIGO and Virgo scientists spotted this merger, they immediately sent out an alert to the astronomical community. Dozens of ground- and space-based telescopes followed up in search of light waves generated in the event, but none picked up any signals. So far, such light counterparts to gravitational-wave signals have been seen only once, in an event called GW170817. That event, discovered by the LIGO-Virgo network in August of 2017, involved a fiery collision between two neutron stars that was subsequently witnessed by dozens of telescopes on Earth and in space. Neutron star collisions are messy affairs with matter flung outward in all directions and are thus expected to shine with light. Conversely, black hole mergers, in most circumstances, are thought not to produce light.

According to the LIGO and Virgo scientists, the August 2019 event was not seen by light-based telescopes for a few possible reasons. First, this event was six times farther away than the merger observed in 2017, making it harder to pick up any light signals. Secondly, if the collision involved two black holes, it likely would have not shone with any light. Thirdly, if the object was in fact a neutron star, its 9-fold more massive black-hole partner might have swallowed it whole; a neutron star consumed whole by a black hole would not give off any light.

“I think of Pac-Man eating a little dot,” says Kalogera. “When the masses are highly asymmetric, the smaller neutron star can be eaten in one bite.”

How will researchers ever know if the mystery object was a neutron star or a black hole? Future observations with LIGO, Virgo, and possibly other telescopes may catch similar events that would help reveal whether additional objects exist in the mass gap.

“This is the first glimpse of what could be a whole new population of compact binary objects,” says Charlie Hoy, a member of the LIGO Scientific Collaboration and a graduate student at Cardiff University. “What is really exciting is that this is just the start. As the detectors get more and more sensitive, we will observe even more of these signals, and we will be able to pinpoint the populations of neutron stars and black holes in the universe.”

“The mass gap has been an interesting puzzle for decades, and now we’ve detected an object that fits just inside it,” says Pedro Marronetti, program director for gravitational physics at the National Science Foundation (NSF). “That cannot be explained without defying our understanding of extremely dense matter or what we know about the evolution of stars. This observation is yet another example of the transformative potential of the field of gravitational-wave astronomy, which brings novel insights with every new detection.”

Bottom line:

Source: GW190814: Gravitational Waves from the Coalescence of a 23 Solar Mass Black Hole with a 2.6 Solar Mass Compact Object

Via LIGO/ Caltech

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

A tribute to Professor Anne Charlton

Professor Anne Charlton was a much-loved colleague who blazed a research trail in cancer education and smoking prevention in schools.

Anne, who died in April aged 84 after contracting COVID-19, was a passionate advocate of the importance of public knowledge about cancer. She combined academic rigour with a down-to-earth and empathetic approach and her contribution to where we are today – in speaking in an open and informed manner about cancer and in driving down youth smoking rates – cannot be overstated.

Anne was a naturally inquisitive child, a trait that followed her throughout her life – from her early interest in botany research to her training and career as a biology teacher in schools in Barrow-in-Furness and Manchester.

It’s a testament to Anne’s energy and enthusiasm that she began her career in cancer research at the age of 39, focusing on cancer education, smoking prevention and the impact of cancer on children.

Cancer education

In the 1970s, cancer was still a taboo subject for many and the fear and misunderstanding it evoked often led to delays in seeking treatment. In 1974, Anne left teaching to take up a research post with the Manchester Regional Committee for Cancer Education.

With the first of many grants from Cancer Research Campaign, a forerunner of Cancer Research UK, Anne began to survey children and teachers’ opinions about cancer. The work led to a master’s degree and a lectureship at Manchester University and set Anne’s course for the next few decades.

Anne went on to explore the possibility of introducing cancer into the curriculum of secondary schools. This project opened up a whole new area of work and led to the development and rigorous evaluation of resources for schools, colleges and teachers – including teaching guides like ‘Cells, Cancers and Communities’ and the ‘Topic of Cancer’.

Through this work, hundreds if not thousands of teachers and education systems around the world were inspired to teach science to children in new ways that made both teaching and learning easier.

This work not only changed the conversation about cancer in schools, it also opened up conversations about smoking.

Children and smoking

By the early 1980s, Cancer Research Campaign (CRC) was beginning to fund research into young people and smoking, Anne conducted a major survey of children and young people in northern England. The research provided a wealth of information about the factors that influence children to take up smoking and revealed that a quarter of 15-16 year-old girls were already regular smokers.

With further funding from the CRC, Anne began to develop new approaches to teaching about cancer, health and tobacco to help delay uptake of smoking and support young smokers to quit.

Anne’s group developed and evaluated many resources for schools and teachers, including a smoking prevention programme for 9-10 year-old children that was also targeted at parents and teachers and a stop-smoking course for young people aged 15-19 years, which was based on the identification of 9 different types of smoker.

Her studies also highlighted external influences that reinforced children’s smoking, including tobacco industry sponsorship of Formula 1 racing and snooker, and contributed to the big push to transform UK government policy to de-normalise smoking.

Impact of cancer on children

With the rapid progress in treatment of many children’s cancers, increasing numbers of children were starting school for the first time or returning to the classroom after a cancer diagnosis and treatment.

Working closely with children’s cancer specialists at the Christie Hospital in Manchester, Anne initiated a detailed study of the experiences of a small group of children and their parents and teachers. This research revealed a number of physical, psychological and academic issues that could impact a child’s return to the classroom.

The success of this pilot led to a much larger study, which showed that teachers needed specific information about a child’s cancer, their treatment and the type of problems that might arise to fully support their pupil in the classroom. Following on from the research, a resource for teachers, ‘Welcome back’, was developed by colleagues in Bristol and Exeter and widely distributed.

Anne’s contribution to cancer education cannot be overstated, but her impact extended far beyond her research projects. She was not a world-renowned expert in her field, she was also a mentor to many researchers, thanks to her undeniable strengths in communication and networking.

Her zest for living was irrepressible. She never retired, continuing to travel, publish and present her research, and to enjoy Shakespeare plays and flower shows to the end of her life.

A good friend and colleague to many, Anne was always ready to offer encouragement and support. She will be greatly missed.

Jean King, Cancer Research UK’s former director of tobacco control and Lesley Walker, Cancer Research UK’s former director of cancer information

from Cancer Research UK – Science blog https://ift.tt/2NnKltw

Professor Anne Charlton was a much-loved colleague who blazed a research trail in cancer education and smoking prevention in schools.

Anne, who died in April aged 84 after contracting COVID-19, was a passionate advocate of the importance of public knowledge about cancer. She combined academic rigour with a down-to-earth and empathetic approach and her contribution to where we are today – in speaking in an open and informed manner about cancer and in driving down youth smoking rates – cannot be overstated.

Anne was a naturally inquisitive child, a trait that followed her throughout her life – from her early interest in botany research to her training and career as a biology teacher in schools in Barrow-in-Furness and Manchester.

It’s a testament to Anne’s energy and enthusiasm that she began her career in cancer research at the age of 39, focusing on cancer education, smoking prevention and the impact of cancer on children.

Cancer education

In the 1970s, cancer was still a taboo subject for many and the fear and misunderstanding it evoked often led to delays in seeking treatment. In 1974, Anne left teaching to take up a research post with the Manchester Regional Committee for Cancer Education.

With the first of many grants from Cancer Research Campaign, a forerunner of Cancer Research UK, Anne began to survey children and teachers’ opinions about cancer. The work led to a master’s degree and a lectureship at Manchester University and set Anne’s course for the next few decades.

Anne went on to explore the possibility of introducing cancer into the curriculum of secondary schools. This project opened up a whole new area of work and led to the development and rigorous evaluation of resources for schools, colleges and teachers – including teaching guides like ‘Cells, Cancers and Communities’ and the ‘Topic of Cancer’.

Through this work, hundreds if not thousands of teachers and education systems around the world were inspired to teach science to children in new ways that made both teaching and learning easier.

This work not only changed the conversation about cancer in schools, it also opened up conversations about smoking.

Children and smoking

By the early 1980s, Cancer Research Campaign (CRC) was beginning to fund research into young people and smoking, Anne conducted a major survey of children and young people in northern England. The research provided a wealth of information about the factors that influence children to take up smoking and revealed that a quarter of 15-16 year-old girls were already regular smokers.

With further funding from the CRC, Anne began to develop new approaches to teaching about cancer, health and tobacco to help delay uptake of smoking and support young smokers to quit.

Anne’s group developed and evaluated many resources for schools and teachers, including a smoking prevention programme for 9-10 year-old children that was also targeted at parents and teachers and a stop-smoking course for young people aged 15-19 years, which was based on the identification of 9 different types of smoker.

Her studies also highlighted external influences that reinforced children’s smoking, including tobacco industry sponsorship of Formula 1 racing and snooker, and contributed to the big push to transform UK government policy to de-normalise smoking.

Impact of cancer on children

With the rapid progress in treatment of many children’s cancers, increasing numbers of children were starting school for the first time or returning to the classroom after a cancer diagnosis and treatment.

Working closely with children’s cancer specialists at the Christie Hospital in Manchester, Anne initiated a detailed study of the experiences of a small group of children and their parents and teachers. This research revealed a number of physical, psychological and academic issues that could impact a child’s return to the classroom.

The success of this pilot led to a much larger study, which showed that teachers needed specific information about a child’s cancer, their treatment and the type of problems that might arise to fully support their pupil in the classroom. Following on from the research, a resource for teachers, ‘Welcome back’, was developed by colleagues in Bristol and Exeter and widely distributed.

Anne’s contribution to cancer education cannot be overstated, but her impact extended far beyond her research projects. She was not a world-renowned expert in her field, she was also a mentor to many researchers, thanks to her undeniable strengths in communication and networking.

Her zest for living was irrepressible. She never retired, continuing to travel, publish and present her research, and to enjoy Shakespeare plays and flower shows to the end of her life.

A good friend and colleague to many, Anne was always ready to offer encouragement and support. She will be greatly missed.

Jean King, Cancer Research UK’s former director of tobacco control and Lesley Walker, Cancer Research UK’s former director of cancer information

from Cancer Research UK – Science blog https://ift.tt/2NnKltw

Hummingbirds see colors we can only imagine

Male broad-tailed hummingbird. Researchers trained birds like these to perform experiments that revealed that the birds see colors invisible to human eyes. Image via Noah Whiteman (UC-Berkeley)/ Princeton University.

You know the old idea that dogs see only in shades of gray? Studies have shown that’s not true. Dogs do see some colors, though their color vision doesn’t reveal a world as richly or intensely colored as the world we see. Now a new study by scientists, published this month in the peer-reviewed journal Proceedings of the National Academy of Sciences, shows that our human color vision can’t compete with that of wild hummingbirds. These fleet little birds perceive a world far more richly hued than ours, full of visual cues humans never notice, via colors we can’t imagine. In fact, said evolutionary biologist Mary (Cassie) Stoddard at Princeton:

Humans are color-blind compared to birds and many other animals.

To other hummingbirds, this male’s magenta throat feathers likely appear as an ultraviolet+purple combination color. Image via David Inouye (U. of Maryland-College Park)/ Princeton University.

When it comes to color vision, you can thank the cone cells in the retina of your eye. Humans have three types of color cones, making us sensitive to red, green and blue light. Birds have a fourth color cone that can detect ultraviolet light. The tiny hummingbirds also see combination colors like ultraviolet+green and ultraviolet+red, according to the new research. The hummingbirds rely on their heightened color sense to find food, dazzle mates, escape predators and navigate diverse terrain, these scientists said.

To investigate how birds perceive color, Stoddard and her research team explored bird color vision in a natural setting. They worked at the Rocky Mountain Biological Laboratory in Gothic, Colorado, training wild broad-tailed hummingbirds (Selasphorus platycercus) to participate in color vision experiments. In the scientists’ statement, Stoddard explained:

Most detailed perceptual experiments on birds are performed in the lab, but we risk missing the bigger picture of how birds really use color vision in their daily lives.

Hummingbirds are perfect for studying color vision in the wild. These sugar fiends have evolved to respond to flower colors that advertise a nectar reward, so they can learn color associations rapidly and with little training.

The team said it was particularly interested in nonspectral color combinations, which involve hues from widely separated parts of the color spectrum. That’s as opposed, they said:

… to blends of neighboring colors like teal (blue-green) or yellow (green-red). For humans, purple is the clearest example of a nonspectral color. Technically, purple is not in the rainbow: it arises when our blue (short-wave) and red (long-wave) cones are stimulated, but not green (medium-wave) cones.

While humans have just one nonspectral color – purple – birds can theoretically see up to five: purple, ultraviolet+red, ultraviolet+green, ultraviolet+yellow and ultraviolet+purple.

View larger. | Infographic by the Stoddard Lab/ Princeton University.

Stoddard and her colleagues designed a series of experiments to test whether hummingbirds can see these nonspectral colors. They performed outdoor experiments each summer for three years, starting with a pair of custom “bird vision” LED tubes programmed to display a broad range of colors, including nonspectral colors like ultraviolet+green. Next, they performed experiments in an alpine meadow frequently visited by local broad-tailed hummingbirds. Their statement said:

Each morning, the researchers rose before dawn and set up two feeders: one containing sugar water and the other plain water. Beside each feeder, they placed an LED tube. The tube beside the sugar water emitted one color, while the one next to the plain water emitted a different color. The researchers periodically swapped the positions of the rewarding and unrewarding tubes, so the birds could not simply use location to pinpoint a sweet treat. They also performed control experiments to ensure that the tiny birds were not using smell or another inadvertent cue to find the reward. Over the course of several hours, wild hummingbirds learned to visit the rewarding color. Using this setup, the researchers recorded over 6,000 feeder visits in a series of 19 experiments.

The experiments revealed that hummingbirds can see a variety of nonspectral colors, including purple, ultraviolet+green, ultraviolet+red and ultraviolet+yellow. For example, hummingbirds readily distinguished ultraviolet+green from pure ultraviolet or pure green, and they discriminated between two different mixtures of ultraviolet+red light – one redder, one less so.

Harold Eyster, a UBC Ph.D. student and a co-author of the study, commented:

It was amazing to watch. The ultraviolet+green light and green light looked identical to us, but the hummingbirds kept correctly choosing the ultraviolet+green light associated with sugar water. Our experiments enabled us to get a sneak peek into what the world looks like to a hummingbird.

Even though hummingbirds can perceive nonspectral colors, appreciating how these colors appear to birds can be difficult, the scientists said. Ben Hogan, a postdoctoral research associate at Princeton and a co-author of the study, commented:

It’s impossible to really know how the birds perceive these colors. Is ultraviolet+red a mix of those colors, or an entirely new color? We can only speculate.

Stoddard added:

To imagine an extra dimension of color vision – that is the thrill and challenge of studying how avian perception works. Fortunately, the hummingbirds reveal that they can see things we cannot.

David Inouye, who is affiliated with the University of Maryland and the center where the study took place, added:

The colors that we see in the fields of wildflowers at our study site, the wildflower capital of Colorado, are stunning to us, but just imagine what those flowers look like to birds with that extra sensory dimension.

The scientists said the wide variety of nonspectral colors available to birds is the result of their ancient four color-cone visual system. Stoddard explained:

Tetrachromacy – having four color cone types – evolved in early vertebrates. This color vision system is the norm for birds, many fish and reptiles, and it almost certainly existed in dinosaurs. We think the ability to perceive many nonspectral colors is not just a feat of hummingbirds but a widespread feature of animal color vision.

The research team studied hummingbirds at the Rocky Mountain Biological Laboratory in Gothic, Colorado. The high-altitude site, at an elevation of nearly 10,000 feet (3,000 meters), is home to many broad-tailed hummingbirds. The research team included (from left): Prof. Mary “Cassie” Stoddard; Cole Morokhovich of the Class of 2020; Harold Eyster, a Ph.D. student at the University of British Columbia; and postdoctoral research associate Ben Hogan. Stoddard, Eyster and Hogan are authors on the paper appearing this week in PNAS. Photo via Princeton University.

Bottom line: A new series of experiments shows that wild hummingbirds perceive a world far more richly colored than ours, full of visual cues humans can never perceive via colors we can’t imagine.

Source: Wild hummingbirds discriminate non-spectral colors

Via Princeton University

from EarthSky https://ift.tt/37QDvGq

Male broad-tailed hummingbird. Researchers trained birds like these to perform experiments that revealed that the birds see colors invisible to human eyes. Image via Noah Whiteman (UC-Berkeley)/ Princeton University.

You know the old idea that dogs see only in shades of gray? Studies have shown that’s not true. Dogs do see some colors, though their color vision doesn’t reveal a world as richly or intensely colored as the world we see. Now a new study by scientists, published this month in the peer-reviewed journal Proceedings of the National Academy of Sciences, shows that our human color vision can’t compete with that of wild hummingbirds. These fleet little birds perceive a world far more richly hued than ours, full of visual cues humans never notice, via colors we can’t imagine. In fact, said evolutionary biologist Mary (Cassie) Stoddard at Princeton:

Humans are color-blind compared to birds and many other animals.

To other hummingbirds, this male’s magenta throat feathers likely appear as an ultraviolet+purple combination color. Image via David Inouye (U. of Maryland-College Park)/ Princeton University.

When it comes to color vision, you can thank the cone cells in the retina of your eye. Humans have three types of color cones, making us sensitive to red, green and blue light. Birds have a fourth color cone that can detect ultraviolet light. The tiny hummingbirds also see combination colors like ultraviolet+green and ultraviolet+red, according to the new research. The hummingbirds rely on their heightened color sense to find food, dazzle mates, escape predators and navigate diverse terrain, these scientists said.

To investigate how birds perceive color, Stoddard and her research team explored bird color vision in a natural setting. They worked at the Rocky Mountain Biological Laboratory in Gothic, Colorado, training wild broad-tailed hummingbirds (Selasphorus platycercus) to participate in color vision experiments. In the scientists’ statement, Stoddard explained:

Most detailed perceptual experiments on birds are performed in the lab, but we risk missing the bigger picture of how birds really use color vision in their daily lives.

Hummingbirds are perfect for studying color vision in the wild. These sugar fiends have evolved to respond to flower colors that advertise a nectar reward, so they can learn color associations rapidly and with little training.

The team said it was particularly interested in nonspectral color combinations, which involve hues from widely separated parts of the color spectrum. That’s as opposed, they said:

… to blends of neighboring colors like teal (blue-green) or yellow (green-red). For humans, purple is the clearest example of a nonspectral color. Technically, purple is not in the rainbow: it arises when our blue (short-wave) and red (long-wave) cones are stimulated, but not green (medium-wave) cones.

While humans have just one nonspectral color – purple – birds can theoretically see up to five: purple, ultraviolet+red, ultraviolet+green, ultraviolet+yellow and ultraviolet+purple.

View larger. | Infographic by the Stoddard Lab/ Princeton University.

Stoddard and her colleagues designed a series of experiments to test whether hummingbirds can see these nonspectral colors. They performed outdoor experiments each summer for three years, starting with a pair of custom “bird vision” LED tubes programmed to display a broad range of colors, including nonspectral colors like ultraviolet+green. Next, they performed experiments in an alpine meadow frequently visited by local broad-tailed hummingbirds. Their statement said:

Each morning, the researchers rose before dawn and set up two feeders: one containing sugar water and the other plain water. Beside each feeder, they placed an LED tube. The tube beside the sugar water emitted one color, while the one next to the plain water emitted a different color. The researchers periodically swapped the positions of the rewarding and unrewarding tubes, so the birds could not simply use location to pinpoint a sweet treat. They also performed control experiments to ensure that the tiny birds were not using smell or another inadvertent cue to find the reward. Over the course of several hours, wild hummingbirds learned to visit the rewarding color. Using this setup, the researchers recorded over 6,000 feeder visits in a series of 19 experiments.

The experiments revealed that hummingbirds can see a variety of nonspectral colors, including purple, ultraviolet+green, ultraviolet+red and ultraviolet+yellow. For example, hummingbirds readily distinguished ultraviolet+green from pure ultraviolet or pure green, and they discriminated between two different mixtures of ultraviolet+red light – one redder, one less so.

Harold Eyster, a UBC Ph.D. student and a co-author of the study, commented:

It was amazing to watch. The ultraviolet+green light and green light looked identical to us, but the hummingbirds kept correctly choosing the ultraviolet+green light associated with sugar water. Our experiments enabled us to get a sneak peek into what the world looks like to a hummingbird.

Even though hummingbirds can perceive nonspectral colors, appreciating how these colors appear to birds can be difficult, the scientists said. Ben Hogan, a postdoctoral research associate at Princeton and a co-author of the study, commented:

It’s impossible to really know how the birds perceive these colors. Is ultraviolet+red a mix of those colors, or an entirely new color? We can only speculate.

Stoddard added:

To imagine an extra dimension of color vision – that is the thrill and challenge of studying how avian perception works. Fortunately, the hummingbirds reveal that they can see things we cannot.

David Inouye, who is affiliated with the University of Maryland and the center where the study took place, added:

The colors that we see in the fields of wildflowers at our study site, the wildflower capital of Colorado, are stunning to us, but just imagine what those flowers look like to birds with that extra sensory dimension.

The scientists said the wide variety of nonspectral colors available to birds is the result of their ancient four color-cone visual system. Stoddard explained:

Tetrachromacy – having four color cone types – evolved in early vertebrates. This color vision system is the norm for birds, many fish and reptiles, and it almost certainly existed in dinosaurs. We think the ability to perceive many nonspectral colors is not just a feat of hummingbirds but a widespread feature of animal color vision.

The research team studied hummingbirds at the Rocky Mountain Biological Laboratory in Gothic, Colorado. The high-altitude site, at an elevation of nearly 10,000 feet (3,000 meters), is home to many broad-tailed hummingbirds. The research team included (from left): Prof. Mary “Cassie” Stoddard; Cole Morokhovich of the Class of 2020; Harold Eyster, a Ph.D. student at the University of British Columbia; and postdoctoral research associate Ben Hogan. Stoddard, Eyster and Hogan are authors on the paper appearing this week in PNAS. Photo via Princeton University.

Bottom line: A new series of experiments shows that wild hummingbirds perceive a world far more richly colored than ours, full of visual cues humans can never perceive via colors we can’t imagine.

Source: Wild hummingbirds discriminate non-spectral colors

Via Princeton University

from EarthSky https://ift.tt/37QDvGq

What is a derecho? An atmospheric scientist explains these rare but dangerous storm systems

A derecho moves across central Kansas on July 3, 2005. Image via Jim Reed/ Corbis/ Getty Images.

By Russ Schumacher, Colorado State University

Thunderstorms are common across North America, especially in warm weather months. About 10% of them become severe, meaning they produce hail 1 inch (2.5 cm) or greater in diameter, winds gusting in excess of 50 knots (57.5 miles per hour, over 90 kph), or a tornado.

The U.S. recently has experienced two rarer events: organized lines of thunderstorms with widespread damaging winds, known as derechos.

Derechos occur mainly across the central and eastern U.S., where many locations are affected one to two times per year on average. They can produce significant damage to structures and sometimes cause “blowdowns” of millions of trees. Pennsylvania and New Jersey received the brunt of a derecho on June 3, 2020, that killed four people and left nearly a million without power across the mid-Atlantic region.

In the West, derechos are less common, but Colorado – where I serve as state climatologist and director of the Colorado Climate Center – experienced a rare and powerful derecho on June 6 that generated winds exceeding 100 miles per hour in some locations. Derechos have also been observed and analyzed in many other parts of the world, including Europe, Asia and South America.

Derechos are an important and active research area in meteorology. I expect that at least one or two more will occur somewhere in the U.S. this summer. Here’s what we know about these unusual storms.

Derechos occur fairly regularly over large parts of the U.S. each year, most commonly from April through August. Image via Dennis Cain/ NOAA.

A massive derecho in June 2012 developed in northern Illinois and traveled to the mid-Atlantic coast, killing 22 and causing $4 billion to $5 billion in damages.

Walls of wind

Scientists have long recognized that organized lines of thunderstorms can produce widespread damaging winds. Gustav Hinrichs, a professor at the University of Iowa, analyzed severe winds in the 1870s and 1880s and identified that many destructive storms were produced by straight-line winds rather than by tornadoes, in which winds rotate. Because the word “tornado,” of Spanish origin, was already in common usage, Hinrichs proposed “derecho” – Spanish for “straight ahead” – for damaging windstorms not associated with tornadoes.

In 1987, meteorologists defined what qualified as a derecho. They proposed that for a storm system to be classified as a derecho, it had to produce severe winds – 57.5 mph (26 meters per second) or greater – and those intense winds had to extend over a path at least 250 miles (400 kilometers) long, with no more than three hours separating individual severe wind reports.

Derechos are almost always caused by a type of weather system known as a bow echo, which has the shape of an archer’s bow on radar images. These in turn are a specific type of mesoscale convective system, a term that describes large, organized groupings of storms.

A derecho affected the central Rockies and northern Plains on Saturday (6/6/20). Derechos are very rare for parts of UT, WY & CO. In fact, only two other derechos are well-documented west of the Rockies. Interested in learning more about derechos? Visit: https://t.co/Na0e8JB4bc pic.twitter.com/XcUI8j5pQQ

— NWS Storm Prediction Center (@NWSSPC) June 8, 2020

Researchers are studying whether and how climate change is affecting weather hazards from thunderstorms. Although some aspects of mesoscale convective systems, such as the amount of rainfall they produce, are very likely to change with continued warming, it’s not yet clear how future climate change may affect the likelihood or intensity of derechos.

Speeding across the landscape

The term “derecho” vaulted into public awareness in June 2012, when one of the most destructive derechos in U.S. history formed in the Midwest and traveled some 700 miles (1,100 km) in 12 hours, eventually making a direct impact on the Washington, D.C. area. This event killed 22 people and caused millions of power outages.

Top: Radar imagery every 2 hours, from 1600 UTC June 29 to 0400 UTC June 30, 2012, combined to show the progression of a derecho-producing bow echo across the central and eastern US. Bottom: Severe wind reports for the June 29-30, 2012, derecho, colored by wind speed. Image via Schumacher and Rasmussen, 2020/ Guastini and Bosart 2016/ Nature.

Only a few recorded derechos had occurred in the western U.S. prior to June 6, 2020. On that day, a line of strong thunderstorms developed in eastern Utah and western Colorado in the late morning. This was unusual in itself, as storms in this region tend to be less organized and occur later in the day.

The thunderstorms continued to organize and moved northeastward across the Rocky Mountains. This was even more unusual: Derecho-producing lines of storms are driven by a pool of cold air near the ground, which would typically be disrupted by a mountain range as tall as the Rockies. In this case, the line remained organized.

As the line of storms emerged to the east of the mountains, it caused widespread wind damage in the Denver metro area and northeastern Colorado. It then strengthened further as it proceeded north-northeastward across eastern Wyoming, western Nebraska and the Dakotas.

In total there were nearly 350 reports of severe winds, including 44 of 75 miles per hour (about 34 meters per second) or greater. The strongest reported gust was 110 mph at Winter Park ski area in the Colorado Rockies. Of these reports, 95 came from Colorado – by far the most severe wind reports ever from a single thunderstorm system.

Animation showing the development and evolution of the June 6-7, 2020, western derecho. Radar reflectivity is shown in the color shading, with National Weather Service warnings shown in the colored outlines (yellow polygons indicate severe thunderstorm warnings). Image via Iowa Environmental Mesonet.

Coloradans are accustomed to big weather, including strong winds in the mountains and foothills. Some of these winds are generated by flow down mountain slopes, localized thunderstorm microbursts, or even “bomb cyclones.” Western thunderstorms more commonly produce hailstorms and tornadoes, so it was very unusual to have a broad swath of the state experience damaging straight-line winds that extended from west of the Rockies all the way to the Dakotas.

Damage comparable to a hurricane

Derechos are challenging to predict. On days when derechos form, it is often uncertain whether any storms will form at all. But if they do, the chance exists for explosive development of intense winds. Forecasters did not anticipate the historic June 2012 derecho until it was already underway.

For the western derecho on June 6, 2020, outlooks showed an enhanced potential for severe storms in Nebraska and the Dakotas two to three days in advance. However, the outlooks didn’t highlight the potential for destructive winds farther south in Colorado until the morning that the derecho formed.

Once a line of storms has begun to develop, however, the National Weather Service routinely issues highly accurate severe thunderstorm warnings 30 to 60 minutes ahead of the arrival of intense winds, alerting the public to take precautions.

Communities, first responders and utilities may have only a few hours to prepare for an oncoming derecho, so it is important to know how to receive severe thunderstorm warnings, such as TV, radio and smartphone alerts, and to take these warnings seriously. Tornadoes and tornado warnings often get the most attention, but lines of severe thunderstorms can also pack a major punch.

Russ Schumacher, Associate Professor of Atmospheric Science and Colorado State Climatologist, Colorado State University

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

Bottom line: What is a derecho? An atmospheric scientist explains these rare but dangerous storm systems.

from EarthSky https://ift.tt/3fU0mU3

A derecho moves across central Kansas on July 3, 2005. Image via Jim Reed/ Corbis/ Getty Images.

By Russ Schumacher, Colorado State University

Thunderstorms are common across North America, especially in warm weather months. About 10% of them become severe, meaning they produce hail 1 inch (2.5 cm) or greater in diameter, winds gusting in excess of 50 knots (57.5 miles per hour, over 90 kph), or a tornado.

The U.S. recently has experienced two rarer events: organized lines of thunderstorms with widespread damaging winds, known as derechos.

Derechos occur mainly across the central and eastern U.S., where many locations are affected one to two times per year on average. They can produce significant damage to structures and sometimes cause “blowdowns” of millions of trees. Pennsylvania and New Jersey received the brunt of a derecho on June 3, 2020, that killed four people and left nearly a million without power across the mid-Atlantic region.

In the West, derechos are less common, but Colorado – where I serve as state climatologist and director of the Colorado Climate Center – experienced a rare and powerful derecho on June 6 that generated winds exceeding 100 miles per hour in some locations. Derechos have also been observed and analyzed in many other parts of the world, including Europe, Asia and South America.

Derechos are an important and active research area in meteorology. I expect that at least one or two more will occur somewhere in the U.S. this summer. Here’s what we know about these unusual storms.

Derechos occur fairly regularly over large parts of the U.S. each year, most commonly from April through August. Image via Dennis Cain/ NOAA.

A massive derecho in June 2012 developed in northern Illinois and traveled to the mid-Atlantic coast, killing 22 and causing $4 billion to $5 billion in damages.

Walls of wind

Scientists have long recognized that organized lines of thunderstorms can produce widespread damaging winds. Gustav Hinrichs, a professor at the University of Iowa, analyzed severe winds in the 1870s and 1880s and identified that many destructive storms were produced by straight-line winds rather than by tornadoes, in which winds rotate. Because the word “tornado,” of Spanish origin, was already in common usage, Hinrichs proposed “derecho” – Spanish for “straight ahead” – for damaging windstorms not associated with tornadoes.

In 1987, meteorologists defined what qualified as a derecho. They proposed that for a storm system to be classified as a derecho, it had to produce severe winds – 57.5 mph (26 meters per second) or greater – and those intense winds had to extend over a path at least 250 miles (400 kilometers) long, with no more than three hours separating individual severe wind reports.

Derechos are almost always caused by a type of weather system known as a bow echo, which has the shape of an archer’s bow on radar images. These in turn are a specific type of mesoscale convective system, a term that describes large, organized groupings of storms.

A derecho affected the central Rockies and northern Plains on Saturday (6/6/20). Derechos are very rare for parts of UT, WY & CO. In fact, only two other derechos are well-documented west of the Rockies. Interested in learning more about derechos? Visit: https://t.co/Na0e8JB4bc pic.twitter.com/XcUI8j5pQQ

— NWS Storm Prediction Center (@NWSSPC) June 8, 2020

Researchers are studying whether and how climate change is affecting weather hazards from thunderstorms. Although some aspects of mesoscale convective systems, such as the amount of rainfall they produce, are very likely to change with continued warming, it’s not yet clear how future climate change may affect the likelihood or intensity of derechos.

Speeding across the landscape

The term “derecho” vaulted into public awareness in June 2012, when one of the most destructive derechos in U.S. history formed in the Midwest and traveled some 700 miles (1,100 km) in 12 hours, eventually making a direct impact on the Washington, D.C. area. This event killed 22 people and caused millions of power outages.

Top: Radar imagery every 2 hours, from 1600 UTC June 29 to 0400 UTC June 30, 2012, combined to show the progression of a derecho-producing bow echo across the central and eastern US. Bottom: Severe wind reports for the June 29-30, 2012, derecho, colored by wind speed. Image via Schumacher and Rasmussen, 2020/ Guastini and Bosart 2016/ Nature.

Only a few recorded derechos had occurred in the western U.S. prior to June 6, 2020. On that day, a line of strong thunderstorms developed in eastern Utah and western Colorado in the late morning. This was unusual in itself, as storms in this region tend to be less organized and occur later in the day.

The thunderstorms continued to organize and moved northeastward across the Rocky Mountains. This was even more unusual: Derecho-producing lines of storms are driven by a pool of cold air near the ground, which would typically be disrupted by a mountain range as tall as the Rockies. In this case, the line remained organized.

As the line of storms emerged to the east of the mountains, it caused widespread wind damage in the Denver metro area and northeastern Colorado. It then strengthened further as it proceeded north-northeastward across eastern Wyoming, western Nebraska and the Dakotas.

In total there were nearly 350 reports of severe winds, including 44 of 75 miles per hour (about 34 meters per second) or greater. The strongest reported gust was 110 mph at Winter Park ski area in the Colorado Rockies. Of these reports, 95 came from Colorado – by far the most severe wind reports ever from a single thunderstorm system.

Animation showing the development and evolution of the June 6-7, 2020, western derecho. Radar reflectivity is shown in the color shading, with National Weather Service warnings shown in the colored outlines (yellow polygons indicate severe thunderstorm warnings). Image via Iowa Environmental Mesonet.

Coloradans are accustomed to big weather, including strong winds in the mountains and foothills. Some of these winds are generated by flow down mountain slopes, localized thunderstorm microbursts, or even “bomb cyclones.” Western thunderstorms more commonly produce hailstorms and tornadoes, so it was very unusual to have a broad swath of the state experience damaging straight-line winds that extended from west of the Rockies all the way to the Dakotas.

Damage comparable to a hurricane

Derechos are challenging to predict. On days when derechos form, it is often uncertain whether any storms will form at all. But if they do, the chance exists for explosive development of intense winds. Forecasters did not anticipate the historic June 2012 derecho until it was already underway.

For the western derecho on June 6, 2020, outlooks showed an enhanced potential for severe storms in Nebraska and the Dakotas two to three days in advance. However, the outlooks didn’t highlight the potential for destructive winds farther south in Colorado until the morning that the derecho formed.

Once a line of storms has begun to develop, however, the National Weather Service routinely issues highly accurate severe thunderstorm warnings 30 to 60 minutes ahead of the arrival of intense winds, alerting the public to take precautions.

Communities, first responders and utilities may have only a few hours to prepare for an oncoming derecho, so it is important to know how to receive severe thunderstorm warnings, such as TV, radio and smartphone alerts, and to take these warnings seriously. Tornadoes and tornado warnings often get the most attention, but lines of severe thunderstorms can also pack a major punch.

Russ Schumacher, Associate Professor of Atmospheric Science and Colorado State Climatologist, Colorado State University

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

Bottom line: What is a derecho? An atmospheric scientist explains these rare but dangerous storm systems.

from EarthSky https://ift.tt/3fU0mU3

Will large parts of Earth be too hot for people in 50 years?

A moonlit night – and stars – above the Sahara Desert in northern Africa. Image via Sergey Pesterev/ Wikimedia Commons.

If greenhouse gas emissions continue unabated, land temperatures will rise so substantially that large areas of Earth will become inhabitable. That’s according to new research by an international team of scientists, published May 26, 2020 in the peer-reviewed journal Proceedings of the National Academy of Sciences.

For several thousands of years, human societies have prospered on lands with hospitable climates, within what scientists call our climate niche. According to the new research, the majority of people have lived within areas where the annual average temperature ranges from 52-59 degrees Fahrenheit (11-15 degrees Celsius), while fewer have inhabited lands with temperatures ranging from 68-77 degrees F (20-25 degrees C). For comparison, the Sahara Desert, one of the hottest regions around the world, has an annual average temperature of 30 degrees C (86 degrees F). Large areas of the Sahara are considered uninhabitable because of the hot and dry conditions, although a few nomadic tribes do live in the desert today.

According to the new research, 50 years from now, if greenhouse gas emissions continue unabated and as Earth’s land surface continues to warm, the area of uninhabitable land will expand drastically. Specifically, these scientists estimate that – without emission reductions – a 13.5 degrees F (7.5 degrees C) rise in land temperatures can be expected by 2070. The global temperature (land plus water) will only rise a bit a more than 5.4 degrees F (3 degrees C) by this time because water does not warm as much as land.

Correspondingly, according to this new research, the area of Earth’s land surface occupied by inhospitably hot temperatures greater than 29 degrees C on average can be expected to rise from a current level of 0.8% today to 19% in 2070.

Map showing the projected expansion in area of inhospitably hot lands caused by climate change. The small black areas represent the land with an average annual temperature of greater than 29 degrees Celsius (84 degrees Fahrenheit) at the present time. The large shaded areas represent the potential extent of such lands in 2070, according to the new research. This map was featured in the May 26, 2020, publication Future of the human climate niche. Image via Wageningen University.

By 2070, this large expansion in uninhabitable land could affect 30% of the projected human population. While some form of adaptation could occur in terms of new cooling technologies for homes, factors such as crop growth, livestock health, and water availability would all contribute to constraints on the livability of these super warm regions. Thus, the pressure for people to migrate would be very high, though the scientists caution that the complexity of migration makes such trends difficult to predict.

Lead author Chi Xu of Nanjing University commented on the findings in a statement:

We were frankly blown away by our own initial results. As our findings were so striking, we took an extra year to carefully check all assumptions and computations. We also decided to publish all data and computer codes for transparency and to facilitate follow-up work by others. The results are as important to China as they are to any other nation. Clearly we will need a global approach to safeguard our children against the potentially enormous social tensions the projected change could invoke.

As sobering as the new findings are, there is still a chance that we can avoid this bleak future by reducing greenhouse gas emissions. Tim Lenton, climate specialist at the University of Exeter and coauthor of the paper said:

The good news is that these impacts can be greatly reduced if humanity succeeds in curbing global warming. Our computations show that each degree warming above present levels corresponds to roughly one billion people falling outside of the climate niche. It is important that we can now express the benefits of curbing greenhouse gas emissions in something more human than just monetary terms.

Bottom line: New research by an international team of scientists indicates that inhospitably hot regions on Earth may expand from a current level of 0.8% to 19% by 2070 if greenhouse gas emissions continue unabated.

Source: Future of the human climate niche

Via Wageningen University

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

A moonlit night – and stars – above the Sahara Desert in northern Africa. Image via Sergey Pesterev/ Wikimedia Commons.

If greenhouse gas emissions continue unabated, land temperatures will rise so substantially that large areas of Earth will become inhabitable. That’s according to new research by an international team of scientists, published May 26, 2020 in the peer-reviewed journal Proceedings of the National Academy of Sciences.

For several thousands of years, human societies have prospered on lands with hospitable climates, within what scientists call our climate niche. According to the new research, the majority of people have lived within areas where the annual average temperature ranges from 52-59 degrees Fahrenheit (11-15 degrees Celsius), while fewer have inhabited lands with temperatures ranging from 68-77 degrees F (20-25 degrees C). For comparison, the Sahara Desert, one of the hottest regions around the world, has an annual average temperature of 30 degrees C (86 degrees F). Large areas of the Sahara are considered uninhabitable because of the hot and dry conditions, although a few nomadic tribes do live in the desert today.

According to the new research, 50 years from now, if greenhouse gas emissions continue unabated and as Earth’s land surface continues to warm, the area of uninhabitable land will expand drastically. Specifically, these scientists estimate that – without emission reductions – a 13.5 degrees F (7.5 degrees C) rise in land temperatures can be expected by 2070. The global temperature (land plus water) will only rise a bit a more than 5.4 degrees F (3 degrees C) by this time because water does not warm as much as land.

Correspondingly, according to this new research, the area of Earth’s land surface occupied by inhospitably hot temperatures greater than 29 degrees C on average can be expected to rise from a current level of 0.8% today to 19% in 2070.

Map showing the projected expansion in area of inhospitably hot lands caused by climate change. The small black areas represent the land with an average annual temperature of greater than 29 degrees Celsius (84 degrees Fahrenheit) at the present time. The large shaded areas represent the potential extent of such lands in 2070, according to the new research. This map was featured in the May 26, 2020, publication Future of the human climate niche. Image via Wageningen University.

By 2070, this large expansion in uninhabitable land could affect 30% of the projected human population. While some form of adaptation could occur in terms of new cooling technologies for homes, factors such as crop growth, livestock health, and water availability would all contribute to constraints on the livability of these super warm regions. Thus, the pressure for people to migrate would be very high, though the scientists caution that the complexity of migration makes such trends difficult to predict.

Lead author Chi Xu of Nanjing University commented on the findings in a statement:

We were frankly blown away by our own initial results. As our findings were so striking, we took an extra year to carefully check all assumptions and computations. We also decided to publish all data and computer codes for transparency and to facilitate follow-up work by others. The results are as important to China as they are to any other nation. Clearly we will need a global approach to safeguard our children against the potentially enormous social tensions the projected change could invoke.

As sobering as the new findings are, there is still a chance that we can avoid this bleak future by reducing greenhouse gas emissions. Tim Lenton, climate specialist at the University of Exeter and coauthor of the paper said:

The good news is that these impacts can be greatly reduced if humanity succeeds in curbing global warming. Our computations show that each degree warming above present levels corresponds to roughly one billion people falling outside of the climate niche. It is important that we can now express the benefits of curbing greenhouse gas emissions in something more human than just monetary terms.

Bottom line: New research by an international team of scientists indicates that inhospitably hot regions on Earth may expand from a current level of 0.8% to 19% by 2070 if greenhouse gas emissions continue unabated.

Source: Future of the human climate niche

Via Wageningen University

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

Getting cancer services back on track during the COVID-19 pandemic

Conversations about COVID-19 are changing. While the impact of COVID-19 on healthcare services across the UK is likely to continue for many months to come, talk is shifting to how to restore healthcare services.

But at a time when our health services are recovering from one major health crisis, we are in danger of creating another – a cancer crisis. Over 2 million people in the UK were left waiting for cancer screening, tests and treatments in the first 10 weeks of lockdown, and that figure is growing.

Cancer services are beginning to get up and running across the country, but we’re still a long way from either restoring capacity or addressing the backlog of people waiting for tests and treatment.

And we can’t just focus on the next few weeks or months. Without a clear plan in each UK nation that looks not just at restoring cancer services over the next few months, but at how we fully recover services and get back on track to transform cancer care, progress on cancer survival could stall.

Here’s what we think needs to happen to make sure patients get the care they need, when they need it.

Creating COVID-protected safe spaces for cancer care

The first, and most pressing, issue is to create COVID-protected safe spaces in hospitals – free, as far as possible, from the COVID-19 virus – to ensure that people can be diagnosed and treated safely and be reassured enough to come forward for care. This requires frequent testing for COVID-19 in all patients and staff working in these spaces, whether they have COVID-19 symptoms or not.

The good news is that COVID-protected safe spaces are being rolled out across the UK. But some hospitals are still struggling to carry out as many tests as they need and get the results quickly enough. For safe spaces to exist, we need to remove the ambiguity.

Each UK nation needs a national strategy to uplift hospital testing capacity, ensure tests are turned around quickly enough and that healthcare workings are tested frequently, prioritising the most needy services first.

We’ve estimated that between 21,000 – 37,000 tests per day, combined with other infection control measures, are required to ensure there are COVID-protected safe spaces for cancer diagnosis and treatment.

> Help us secure safe spaces for cancer services by emailing your MP

Ensuring these COVID-protected safe spaces are fully functional will be vital to managing the backlog and rebuilding trust in cancer services. But it must be combined with awareness campaigns so that people with potential cancer symptoms are encouraged to seek help from health professionals and feel safe doing so.

At the beginning of the coronavirus outbreak, the number of people being urgently referred for suspected cancer dropped by up to 75%, meaning far fewer people were getting diagnostic tests, equating to some 2,300 cancers a week not being diagnosed through this route. And while the number of urgent referrals is steadily rising, they remain lower than usual, and the backlog of patients requiring diagnostic tests continues to build.

And it’s not just urgent cancer referrals that have been affected. All national cancer screening programmes were effectively paused in each UK nation by the coronavirus pandemic, which means up to 1.2 million invitations to take part in bowel, breast and cervical screening were not being sent out each month. And chemotherapy, radiotherapy and surgery cases dropped, leaving thousands of patients waiting for life-saving cancer treatment.

So far, we have estimates of how many people are affected. But for local services to plan how they will catch up, and the capacity they will need, health services need to provide clear and high-quality data on the scale of the disruption over the past 4 months and a detailed assessment of who will need tests or treatment most urgently.

As the UK could face multiple waves of COVID-19 cases – these figures will also help health services to prepare for these scenarios, with the aim of keeping cancer services running as much and as safely as possible.

Restarting clinical trials

A vital part of getting cancer services back on track is restarting clinical trials. COVID-19 has had a huge impact on the UK’s ability to run clinical trials, with the number of new patients being recruit on to UK-based trials falling by 95% in April 2020 compared with April 2019.

Without clinical trials, the potential pipeline of new or improved cancer treatment options stalls, so restarting clinical trials should be a priority.

Things are starting to move in the right direction – the National Institute for Health Research has published a framework outlining conditions that must be met before clinical trials start as well as criteria for prioritising which trials should be restarted first.

But while cancer trials are starting to re-open to new patients, right now the highest priority level is reserved for COVID-19 trials. To ensure that cancer clinical trials are not seen as less of a priority when it comes to getting trials back up and running, we believe the highest priority level should be expanded to include urgent non-COVID studies, especially studies that provide safer alternatives treatments in a COVID-19 environment.

Preventing cancer

For healthcare to truly be back on track, we need to think bigger than cancer diagnosis and treatment. Smoking continues to be the biggest preventable cause of cancer, illness and death in the UK, and recent research suggests that people who smoke are more likely to experience severe COVID-19 symptoms than non-smokers.

Most stop smoking services in the UK responded quickly to the COVID-19 pandemic and have adapted their service to ensure people could continue receiving behavioural support over the phone, through videoconference or via email, text messaging or apps.

Many services have also found innovative ways of delivering stop smoking therapies to people during the period of lockdown, including sending prescriptions to pharmacies for collection or posting these medications directly to people who need them. It’s vital that people who smoke continue to be provided with professional support to give them the best chance of stopping smoking, with support delivered virtually. This relies on specialist support receiving enough funding on a national and local level.

Workforce and innovation

Healthcare staff are central to the recovery of cancer services and action must be taken to increase and retain staff working in cancer care. This is not a new issue, before the COVID-19 crisis there were around 1 in 10 diagnostic posts unfilled across the health service. But it’s become even more pressing during the pandemic, as the backlog of people waiting for tests or treatment has grown.

To manage this, there must be a clear understanding of how COVID-19 has affected the number of staff in specific cancer professions, and health services must take steps to train and increase the workforce where it’s most needed. In the longer term, each UK nation needs a fully-funded workforce plan to make sure there are enough staff in the future to support the rising incidence of cancer.

While the crisis has placed unimaginable strain on the healthcare service, it’s also forced services to find new and innovative ways of working, by reconfiguring services and embracing technology.

We must make sure that we learn from these changes, scaling up innovations that have worked well. As much of this has been driven at a local level, we need national health leaders, hospitals and clinicians to work together to make this happen.

Moving forward

COVID-19 has changed the game, and health services and governments need to act now to ensure that cancer tests, treatment and care can recover following the COVID-19 peak. Our chief executive officer, Michelle Mitchell, alongside other charities, has written to the Prime Minister to help kickstart a national conversation about our longer-term ambitions in cancer. And our teams in Scotland, Wales and Northern Ireland will work with the relevant governments to deliver our ambitions in each UK nation.

We know that cancer survival and outcomes can improve, despite COVID-19, and we should be aiming to catch up with others in the world. But in order to give patients the care they deserve, the UK and devolved governments must commit to an ambitious cancer agenda.

Khruti Shrotri is a policy manager at Cancer Research UK

We need your help to secure safe spaces for cancer services.

> Demand urgent action now 

from Cancer Research UK – Science blog https://ift.tt/3fLYdd9

Conversations about COVID-19 are changing. While the impact of COVID-19 on healthcare services across the UK is likely to continue for many months to come, talk is shifting to how to restore healthcare services.

But at a time when our health services are recovering from one major health crisis, we are in danger of creating another – a cancer crisis. Over 2 million people in the UK were left waiting for cancer screening, tests and treatments in the first 10 weeks of lockdown, and that figure is growing.

Cancer services are beginning to get up and running across the country, but we’re still a long way from either restoring capacity or addressing the backlog of people waiting for tests and treatment.

And we can’t just focus on the next few weeks or months. Without a clear plan in each UK nation that looks not just at restoring cancer services over the next few months, but at how we fully recover services and get back on track to transform cancer care, progress on cancer survival could stall.

Here’s what we think needs to happen to make sure patients get the care they need, when they need it.

Creating COVID-protected safe spaces for cancer care

The first, and most pressing, issue is to create COVID-protected safe spaces in hospitals – free, as far as possible, from the COVID-19 virus – to ensure that people can be diagnosed and treated safely and be reassured enough to come forward for care. This requires frequent testing for COVID-19 in all patients and staff working in these spaces, whether they have COVID-19 symptoms or not.

The good news is that COVID-protected safe spaces are being rolled out across the UK. But some hospitals are still struggling to carry out as many tests as they need and get the results quickly enough. For safe spaces to exist, we need to remove the ambiguity.

Each UK nation needs a national strategy to uplift hospital testing capacity, ensure tests are turned around quickly enough and that healthcare workings are tested frequently, prioritising the most needy services first.

We’ve estimated that between 21,000 – 37,000 tests per day, combined with other infection control measures, are required to ensure there are COVID-protected safe spaces for cancer diagnosis and treatment.

> Help us secure safe spaces for cancer services by emailing your MP

Ensuring these COVID-protected safe spaces are fully functional will be vital to managing the backlog and rebuilding trust in cancer services. But it must be combined with awareness campaigns so that people with potential cancer symptoms are encouraged to seek help from health professionals and feel safe doing so.

At the beginning of the coronavirus outbreak, the number of people being urgently referred for suspected cancer dropped by up to 75%, meaning far fewer people were getting diagnostic tests, equating to some 2,300 cancers a week not being diagnosed through this route. And while the number of urgent referrals is steadily rising, they remain lower than usual, and the backlog of patients requiring diagnostic tests continues to build.

And it’s not just urgent cancer referrals that have been affected. All national cancer screening programmes were effectively paused in each UK nation by the coronavirus pandemic, which means up to 1.2 million invitations to take part in bowel, breast and cervical screening were not being sent out each month. And chemotherapy, radiotherapy and surgery cases dropped, leaving thousands of patients waiting for life-saving cancer treatment.

So far, we have estimates of how many people are affected. But for local services to plan how they will catch up, and the capacity they will need, health services need to provide clear and high-quality data on the scale of the disruption over the past 4 months and a detailed assessment of who will need tests or treatment most urgently.

As the UK could face multiple waves of COVID-19 cases – these figures will also help health services to prepare for these scenarios, with the aim of keeping cancer services running as much and as safely as possible.

Restarting clinical trials

A vital part of getting cancer services back on track is restarting clinical trials. COVID-19 has had a huge impact on the UK’s ability to run clinical trials, with the number of new patients being recruit on to UK-based trials falling by 95% in April 2020 compared with April 2019.

Without clinical trials, the potential pipeline of new or improved cancer treatment options stalls, so restarting clinical trials should be a priority.

Things are starting to move in the right direction – the National Institute for Health Research has published a framework outlining conditions that must be met before clinical trials start as well as criteria for prioritising which trials should be restarted first.

But while cancer trials are starting to re-open to new patients, right now the highest priority level is reserved for COVID-19 trials. To ensure that cancer clinical trials are not seen as less of a priority when it comes to getting trials back up and running, we believe the highest priority level should be expanded to include urgent non-COVID studies, especially studies that provide safer alternatives treatments in a COVID-19 environment.

Preventing cancer

For healthcare to truly be back on track, we need to think bigger than cancer diagnosis and treatment. Smoking continues to be the biggest preventable cause of cancer, illness and death in the UK, and recent research suggests that people who smoke are more likely to experience severe COVID-19 symptoms than non-smokers.

Most stop smoking services in the UK responded quickly to the COVID-19 pandemic and have adapted their service to ensure people could continue receiving behavioural support over the phone, through videoconference or via email, text messaging or apps.

Many services have also found innovative ways of delivering stop smoking therapies to people during the period of lockdown, including sending prescriptions to pharmacies for collection or posting these medications directly to people who need them. It’s vital that people who smoke continue to be provided with professional support to give them the best chance of stopping smoking, with support delivered virtually. This relies on specialist support receiving enough funding on a national and local level.

Workforce and innovation

Healthcare staff are central to the recovery of cancer services and action must be taken to increase and retain staff working in cancer care. This is not a new issue, before the COVID-19 crisis there were around 1 in 10 diagnostic posts unfilled across the health service. But it’s become even more pressing during the pandemic, as the backlog of people waiting for tests or treatment has grown.

To manage this, there must be a clear understanding of how COVID-19 has affected the number of staff in specific cancer professions, and health services must take steps to train and increase the workforce where it’s most needed. In the longer term, each UK nation needs a fully-funded workforce plan to make sure there are enough staff in the future to support the rising incidence of cancer.

While the crisis has placed unimaginable strain on the healthcare service, it’s also forced services to find new and innovative ways of working, by reconfiguring services and embracing technology.

We must make sure that we learn from these changes, scaling up innovations that have worked well. As much of this has been driven at a local level, we need national health leaders, hospitals and clinicians to work together to make this happen.

Moving forward

COVID-19 has changed the game, and health services and governments need to act now to ensure that cancer tests, treatment and care can recover following the COVID-19 peak. Our chief executive officer, Michelle Mitchell, alongside other charities, has written to the Prime Minister to help kickstart a national conversation about our longer-term ambitions in cancer. And our teams in Scotland, Wales and Northern Ireland will work with the relevant governments to deliver our ambitions in each UK nation.

We know that cancer survival and outcomes can improve, despite COVID-19, and we should be aiming to catch up with others in the world. But in order to give patients the care they deserve, the UK and devolved governments must commit to an ambitious cancer agenda.

Khruti Shrotri is a policy manager at Cancer Research UK

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from Cancer Research UK – Science blog https://ift.tt/3fLYdd9

Young moon after sunset June 22, 23 and 24

By June 22, 2020, the annular solar eclipse has passed. From the Americas, it might have been possible to catch the skinniest of lunar crescents at dusk June 21, though binoculars would have been needed to glimpse the frail crescent that’s only about 0.5 percent illuminated in sunshine. For most of us, the young moon will return to the west after sunset on June 22, 23 and 24. Finding an unobstructed western horizon will be most helpful – especially on June 22 – when a whisker-thin lunar crescent will sit low in the west at sunset and will follow the sun beneath the horizon shortly thereafter. Most likely, on June 22, the thin crescent will set before nightfall. On the following evenings – June 23 and 24 – the young moon will be higher up after sunset and easier to see, but don’t delay. These young crescent moons all follow the sun below the western horizon in early evening.

Find out when the moon sets in your sky via TimeandDate.com

The moon swept to its new phase on June 21, 2020, at 06:41 UTC, giving birth to the new lunar month (Brown Lunation Number 1206).

Normally, the moon is not seen from Earth at new phase. At that time, the moon’s dark side is facing Earth, with the moon as a whole traveling near the sun in our daytime sky, lost in the sun’s glare. You’ll typically see the young moon return to the evening sky a day or two after new moon.

At the June 21 new moon, a number of people living in the world’s Eastern Hemisphere did see the moon during daylight hours. That’s because the new moon swung smack-dab in front of the sun, causing a solar eclipse. A small slice of the world saw this annular – or ring – solar eclipse. At mid-eclipse, the new moon silhouette was surrounded by a thin ring – or annulus – of the sun’s surface. A much larger swath of the world saw the new moon take a bite out of the solar disk: a partial eclipse of the sun.

Read more: Annular solar eclipse on June 21, 2020

Those who watched the June 21 solar eclipse – either in the sky or online – were viewing the moon’s night side. Now daylight is returning to the side of the moon we see. Assuming you don’t see the moon in your evening sky on June 21 (and most of us won’t), the first thin slice of illumination on the near side of the moon will be visible after sunset June 22.

Day by day, the moon moves a little over 12 degrees eastward of the setting sun. (For reference, the moon’s angular diameter spans about 1/2 degree of sky, and your fist at arm’s length measures approximately 10 degrees.) That means a wider lunar crescent will be higher in the sky at sunset, and will stay out longer after dark. In other words, the moon will be easier to catch after sundown on June 23 than on June 22, and on June 24 than June 23.

Above photo: Peter Lowenstein of Mutare, Zimbabwe, caught the young moon, with its dark side all aglow in earthshine, after sunset September 29, 2019.

While you’re enjoying the beauty of a young moon these next several days, note the soft glow of earthshine on the dark side of the moon. Earthshine is twice-reflected sunlight, with sunlight reflected from Earth hitting the moon, and then bouncing back to Earth.

Read more: What is earthshine?

Bottom line: These next several days – June 22, 23 and 24, 2020 – watch for the young moon to adorn your western twilight sky.

from EarthSky https://ift.tt/31hWetl

By June 22, 2020, the annular solar eclipse has passed. From the Americas, it might have been possible to catch the skinniest of lunar crescents at dusk June 21, though binoculars would have been needed to glimpse the frail crescent that’s only about 0.5 percent illuminated in sunshine. For most of us, the young moon will return to the west after sunset on June 22, 23 and 24. Finding an unobstructed western horizon will be most helpful – especially on June 22 – when a whisker-thin lunar crescent will sit low in the west at sunset and will follow the sun beneath the horizon shortly thereafter. Most likely, on June 22, the thin crescent will set before nightfall. On the following evenings – June 23 and 24 – the young moon will be higher up after sunset and easier to see, but don’t delay. These young crescent moons all follow the sun below the western horizon in early evening.

Find out when the moon sets in your sky via TimeandDate.com

The moon swept to its new phase on June 21, 2020, at 06:41 UTC, giving birth to the new lunar month (Brown Lunation Number 1206).

Normally, the moon is not seen from Earth at new phase. At that time, the moon’s dark side is facing Earth, with the moon as a whole traveling near the sun in our daytime sky, lost in the sun’s glare. You’ll typically see the young moon return to the evening sky a day or two after new moon.

At the June 21 new moon, a number of people living in the world’s Eastern Hemisphere did see the moon during daylight hours. That’s because the new moon swung smack-dab in front of the sun, causing a solar eclipse. A small slice of the world saw this annular – or ring – solar eclipse. At mid-eclipse, the new moon silhouette was surrounded by a thin ring – or annulus – of the sun’s surface. A much larger swath of the world saw the new moon take a bite out of the solar disk: a partial eclipse of the sun.

Read more: Annular solar eclipse on June 21, 2020

Those who watched the June 21 solar eclipse – either in the sky or online – were viewing the moon’s night side. Now daylight is returning to the side of the moon we see. Assuming you don’t see the moon in your evening sky on June 21 (and most of us won’t), the first thin slice of illumination on the near side of the moon will be visible after sunset June 22.

Day by day, the moon moves a little over 12 degrees eastward of the setting sun. (For reference, the moon’s angular diameter spans about 1/2 degree of sky, and your fist at arm’s length measures approximately 10 degrees.) That means a wider lunar crescent will be higher in the sky at sunset, and will stay out longer after dark. In other words, the moon will be easier to catch after sundown on June 23 than on June 22, and on June 24 than June 23.

Above photo: Peter Lowenstein of Mutare, Zimbabwe, caught the young moon, with its dark side all aglow in earthshine, after sunset September 29, 2019.

While you’re enjoying the beauty of a young moon these next several days, note the soft glow of earthshine on the dark side of the moon. Earthshine is twice-reflected sunlight, with sunlight reflected from Earth hitting the moon, and then bouncing back to Earth.

Read more: What is earthshine?

Bottom line: These next several days – June 22, 23 and 24, 2020 – watch for the young moon to adorn your western twilight sky.

from EarthSky https://ift.tt/31hWetl