Find the Crow, Cup and Water Snake

Tonight, or any June evening, look south and west (below and to the right) of the star Spica for the constellations of Corvus the Crow, Crater the Cup, and Hydra the Water Snake.

You’ll be looking in the south to southwest sky around nightfall. In 2018, the brilliant “star” to the east (left) of the star Spica is really the planet Jupiter, which lights up the sky almost as soon as the sun goes down. Jupiter is near Zubenelgenubi, the alpha star in the constellation Libra the Scales. And Spica, the brightest star in the constellation Virgo, is your guide to the Crow, Cup and Water Snake.

Okay … got Spica? Now, as nightfall deepens into later evening, watch for a number of fainter stars to become visible. That’s when the Crow, Cup and the Water Snake will come into view.

In Greek mythology, Apollo sent the crow to fetch a cup of water. The crow, Corvus, got distracted eating figs. It was only after much delay that he finally remembered his mission. Rightly figuring that Apollo would be angry, the crow plucked a snake from the water and concocted a story about how it had attacked and delayed him.

Hydra the Water Snake with the orange star Alphard at its heart. Illustration via Deanspace.

Apollo was not fooled and angrily flung the Crow, Cup and Snake into the sky, placing the Crow and Cup on the Snake’s back.

Then the god ordered Hydra to never let the Crow drink from the Cup. As a further punishment, he ordered that the Crow could never sing again, only screech and caw.

None of these constellations has any bright stars, but Hydra holds the distinction of being the longest constellation in the heavens.

Bottom line: Use the bright star Spica to help you find the constellations of Corvus the Crow, Crater the Cup, and Hydra the Water Snake.

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from EarthSky https://ift.tt/1ROig9u

Tonight, or any June evening, look south and west (below and to the right) of the star Spica for the constellations of Corvus the Crow, Crater the Cup, and Hydra the Water Snake.

You’ll be looking in the south to southwest sky around nightfall. In 2018, the brilliant “star” to the east (left) of the star Spica is really the planet Jupiter, which lights up the sky almost as soon as the sun goes down. Jupiter is near Zubenelgenubi, the alpha star in the constellation Libra the Scales. And Spica, the brightest star in the constellation Virgo, is your guide to the Crow, Cup and Water Snake.

Okay … got Spica? Now, as nightfall deepens into later evening, watch for a number of fainter stars to become visible. That’s when the Crow, Cup and the Water Snake will come into view.

In Greek mythology, Apollo sent the crow to fetch a cup of water. The crow, Corvus, got distracted eating figs. It was only after much delay that he finally remembered his mission. Rightly figuring that Apollo would be angry, the crow plucked a snake from the water and concocted a story about how it had attacked and delayed him.

Hydra the Water Snake with the orange star Alphard at its heart. Illustration via Deanspace.

Apollo was not fooled and angrily flung the Crow, Cup and Snake into the sky, placing the Crow and Cup on the Snake’s back.

Then the god ordered Hydra to never let the Crow drink from the Cup. As a further punishment, he ordered that the Crow could never sing again, only screech and caw.

None of these constellations has any bright stars, but Hydra holds the distinction of being the longest constellation in the heavens.

Bottom line: Use the bright star Spica to help you find the constellations of Corvus the Crow, Crater the Cup, and Hydra the Water Snake.

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

from EarthSky https://ift.tt/1ROig9u

Combining heartburn drugs and aspirin could help prevent oesophageal cancer in people at high risk

In the famous words of Benjamin Franklin: “An ounce of prevention is worth a pound of cure.”

While he may have been talking about fire safety rather than disease, this sentiment rings true for cancer too. If there was a way to stop cancer from developing, then the stress, costs and side effects that come with a diagnosis and treatment could be avoided.

The challenge is that not all cancers are preventable, and there’s no elixir of life to help us get around the biggest risk factor for the disease – getting older. But some can be prevented – around 4 in 10 in the UK – meaning there’s an opportunity to act and help reduce the burden of the disease.

For cancers where survival remains poor, like oesophageal cancer, there’s potential to make the greatest difference for people. That’s why many of our scientists are working in this area, and new research showcases the progress they’re making.

A new Cancer Research UK-funded clinical trial has found that two over-the-counter, widely available drugs could help cut cases of oesophageal cancer in people at higher risk of the disease. And when these drugs – a stomach acid blocker and aspirin – were used together, their effects were even greater.

“We weren’t expecting such overwhelmingly positive data,” says lead author Prof Janusz Jankowski from the Royal College of Surgeons in Ireland, who is presenting the findings at the 2018 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.

“The drugs caused a reduction in overall death and oesophageal cancers. It really surprised us how big the effect was, the effect for strong acid prevention was 4 times higher than we expected.”

Questions remain, such as who might benefit most from these drugs, and can they specifically prevent deaths from oesophageal cancer? But the findings mark an important step towards progress against a disease that has lagged others.

Risk and reason

Oesophageal cancer begins in the food pipe (oesophagus). The disease often doesn’t cause clear symptoms during its early stages, meaning many cases are diagnosed late when they’ve spread and become difficult to treat. That’s one of the main reasons why survival for oesophageal cancer is stubbornly low, with just over 1 in 10 people surviving their disease for a decade or longer.

It’s time for this grim situation to be turned around, and our researchers are showing that’s possible.

This latest study centres on one of the risk factors for oesophageal cancer, a condition called Barrett’s oesophagus. This is where the cells that line the food pipe change from a layered, brick wall to looking more like a picket fence. Normally, this happens because of stomach acid making its way up the food pipe (acid reflux) and damaging the cells.

Over time, these cells can become so different to healthy cells that they turn cancerous. This only happens to between 1 and 5 people in every 100 with Barrett’s oesophagus, but with acid reflux on the rise, there’s an opportunity to intervene and make a difference.

Mining for gold

For the study, scientists wanted to find out whether giving people with Barrett’s oesophagus a drug – called a proton pump inhibitor (PPI) – to treat their acid reflux could prevent their condition from worsening, and cut cases of oesophageal cancer. They also wanted to test whether adding aspirin could have a beneficial effect too.

Working across the UK and Canada, the team recruited more than 2,557 adults with Barrett’s oesophagus and randomly assigned them one of four treatments every day:

• A high dose of PPI with aspirin
• A high dose of PPI without aspirin
• A low dose of PPI with aspirin
• A low dose of PPI without aspirin

These people were then followed for an average of 9 years, amounting to a mammoth 20,000 years of patient data.

“It’s the longest of its kind in terms of follow up,” says Jankowski. “And no one had ever looked at combining PPIs and aspirin before for cancer prevention. That’s meant it’s been building a real gold mine for data collection.”

When they dug into this data gold mine, they found that high dose PPI treatment not only reduced progression of people’s Barrett’s oesophagus, but cases of oesophageal cancer and the number of people dying from any cause were lower too. And when aspirin was added in to the mix, the effect was even greater.

“We were expecting PPI treatment to maybe reduce cases of oesophageal cancer by about 5%,” says Jankowski.

“But we found the reduction was more like 20% in people given a high daily dose, which took us all by shock.”

Importantly, the drugs seemed to be safe too, with very few people experiencing side effects. But this is an important concern with using drugs to prevent cancer in this way, particularly aspirin, which is linked with bleeding risks when used long-term.

A case for change

So, what is it about this combination that seems to be so effective? While PPIs work by taming the cells’ environment, making it less hostile from the stomach acid, aspirin is thought to have a calming effect on growing cells.

“If we imagine a cell as a car careeing down a motorway, aspirin is like a speed regulator. It slows down cell metabolism and generally dampens down ‘go’ signals that could accelerate growth,” explains Jankowski.

There’s no question of whether this study will be practice-changing.

– Professor Jankowski

“Whereas PPIs are like the truck that sprays grit on the road surface, making it less likely that the car will skid out of control when conditions become unfavourable.”

And with such encouraging results, Jankowski doesn’t think it will be long before the findings will hopefully start helping people outside of clinical trials.

“There’s no question of whether this study will be practice-changing,” he says. “We found low dose PPI therapy isn’t as effective as high dose, so the results could alter their use.”

But there are other questions remaining. How long do patients need to take these drugs for them to have a beneficial effect? Who is most likely to benefit from taking them? And importantly, can they prevent deaths specifically from oesophageal cancer?

These will be the focus of future research. And Jankowski says the researchers are already drawing up plans to extend the study and begin answering these questions. With that clarity, hopefully this work can begin making an impact on people’s lives.

Justine

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

In the famous words of Benjamin Franklin: “An ounce of prevention is worth a pound of cure.”

While he may have been talking about fire safety rather than disease, this sentiment rings true for cancer too. If there was a way to stop cancer from developing, then the stress, costs and side effects that come with a diagnosis and treatment could be avoided.

The challenge is that not all cancers are preventable, and there’s no elixir of life to help us get around the biggest risk factor for the disease – getting older. But some can be prevented – around 4 in 10 in the UK – meaning there’s an opportunity to act and help reduce the burden of the disease.

For cancers where survival remains poor, like oesophageal cancer, there’s potential to make the greatest difference for people. That’s why many of our scientists are working in this area, and new research showcases the progress they’re making.

A new Cancer Research UK-funded clinical trial has found that two over-the-counter, widely available drugs could help cut cases of oesophageal cancer in people at higher risk of the disease. And when these drugs – a stomach acid blocker and aspirin – were used together, their effects were even greater.

“We weren’t expecting such overwhelmingly positive data,” says lead author Prof Janusz Jankowski from the Royal College of Surgeons in Ireland, who is presenting the findings at the 2018 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.

“The drugs caused a reduction in overall death and oesophageal cancers. It really surprised us how big the effect was, the effect for strong acid prevention was 4 times higher than we expected.”

Questions remain, such as who might benefit most from these drugs, and can they specifically prevent deaths from oesophageal cancer? But the findings mark an important step towards progress against a disease that has lagged others.

Risk and reason

Oesophageal cancer begins in the food pipe (oesophagus). The disease often doesn’t cause clear symptoms during its early stages, meaning many cases are diagnosed late when they’ve spread and become difficult to treat. That’s one of the main reasons why survival for oesophageal cancer is stubbornly low, with just over 1 in 10 people surviving their disease for a decade or longer.

It’s time for this grim situation to be turned around, and our researchers are showing that’s possible.

This latest study centres on one of the risk factors for oesophageal cancer, a condition called Barrett’s oesophagus. This is where the cells that line the food pipe change from a layered, brick wall to looking more like a picket fence. Normally, this happens because of stomach acid making its way up the food pipe (acid reflux) and damaging the cells.

Over time, these cells can become so different to healthy cells that they turn cancerous. This only happens to between 1 and 5 people in every 100 with Barrett’s oesophagus, but with acid reflux on the rise, there’s an opportunity to intervene and make a difference.

Mining for gold

For the study, scientists wanted to find out whether giving people with Barrett’s oesophagus a drug – called a proton pump inhibitor (PPI) – to treat their acid reflux could prevent their condition from worsening, and cut cases of oesophageal cancer. They also wanted to test whether adding aspirin could have a beneficial effect too.

Working across the UK and Canada, the team recruited more than 2,557 adults with Barrett’s oesophagus and randomly assigned them one of four treatments every day:

• A high dose of PPI with aspirin
• A high dose of PPI without aspirin
• A low dose of PPI with aspirin
• A low dose of PPI without aspirin

These people were then followed for an average of 9 years, amounting to a mammoth 20,000 years of patient data.

“It’s the longest of its kind in terms of follow up,” says Jankowski. “And no one had ever looked at combining PPIs and aspirin before for cancer prevention. That’s meant it’s been building a real gold mine for data collection.”

When they dug into this data gold mine, they found that high dose PPI treatment not only reduced progression of people’s Barrett’s oesophagus, but cases of oesophageal cancer and the number of people dying from any cause were lower too. And when aspirin was added in to the mix, the effect was even greater.

“We were expecting PPI treatment to maybe reduce cases of oesophageal cancer by about 5%,” says Jankowski.

“But we found the reduction was more like 20% in people given a high daily dose, which took us all by shock.”

Importantly, the drugs seemed to be safe too, with very few people experiencing side effects. But this is an important concern with using drugs to prevent cancer in this way, particularly aspirin, which is linked with bleeding risks when used long-term.

A case for change

So, what is it about this combination that seems to be so effective? While PPIs work by taming the cells’ environment, making it less hostile from the stomach acid, aspirin is thought to have a calming effect on growing cells.

“If we imagine a cell as a car careeing down a motorway, aspirin is like a speed regulator. It slows down cell metabolism and generally dampens down ‘go’ signals that could accelerate growth,” explains Jankowski.

There’s no question of whether this study will be practice-changing.

– Professor Jankowski

“Whereas PPIs are like the truck that sprays grit on the road surface, making it less likely that the car will skid out of control when conditions become unfavourable.”

And with such encouraging results, Jankowski doesn’t think it will be long before the findings will hopefully start helping people outside of clinical trials.

“There’s no question of whether this study will be practice-changing,” he says. “We found low dose PPI therapy isn’t as effective as high dose, so the results could alter their use.”

But there are other questions remaining. How long do patients need to take these drugs for them to have a beneficial effect? Who is most likely to benefit from taking them? And importantly, can they prevent deaths specifically from oesophageal cancer?

These will be the focus of future research. And Jankowski says the researchers are already drawing up plans to extend the study and begin answering these questions. With that clarity, hopefully this work can begin making an impact on people’s lives.

Justine

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

Big and Little Dippers easy on June evenings

Tonight, assuming you’re in the Northern Hemisphere, you can easily find the legendary Big Dipper, called The Plough by our friends in the U.K. or The Wagon throughout much of Europe. This familiar star pattern is high in the north at nightfall in June. Find it, and let it be your guide to the Little Dipper, too.

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

You can find the Big Dipper easily because its shape really resembles a dipper. Meanwhile, the Little Dipper isn’t as easy to find. You need a dark sky to see the Little Dipper, so be sure to avoid city lights.

How do you find the Dippers? Assuming you’re in the Northern Hemisphere, simply face northward on a June evening, and watch for a large dipper-like pattern. That easy-to-see pattern will be the Big Dipper. Notice that the Big Dipper has two parts: a bowl and a handle. See the two outer stars in the bowl? They’re known as The Pointers because they point to the North Star, which is also known as Polaris.

Once you’ve found Polaris, you can find the Little Dipper. Polaris marks the end of the handle of the Little Dipper. You need a dark night to see the Little Dipper in full, because it’s so much fainter than its larger and brighter counterpart.

By the way, can you see the Big Dipper from Earth’s Southern Hemisphere? Yes, if you’re in the southern tropics. Much farther south, and it gets harder; as you go southward on Earth’s globe, the Dipper sinks closer and closer to the northern horizon.

Meanwhile, Polaris, the North Star, disappears beneath the horizon once you get south of the Earth’s equator.

The Big and Little Dippers aren’t constellations. They’re asterisms, or noticeable star patterns. The Big Dipper is part of Ursa Major the Greater Bear. The Little Dipper belongs to Ursa Minor the Lesser Bear. Image via Dill Knob Observatory.

Richard Hinkley Allen in his book Star Names: Their Lore and Meaning claims the Greek constellation Ursa Minor was never mentioned in the literary works of Homer (9th century B.C.) or Hesiod (8th century B.C.). That’s probably because this constellation hadn’t been invented yet, that long ago.

According to the Greek geographer and historian Strabo (63 B.C. to A.D. 21?), the seven stars we see today as part of Ursa Minor (the Little Dipper) didn’t carry that name until 600 B.C. or so. Before that time, people saw this group of stars outlining the wings of the constellation Draco the Dragon.

When the seafaring Phoenicians visited the Greek philosopher Thales around 600 B.C., they showed him how to navigate by the stars. Purportedly, Thales clipped the Dragon’s wings to create a new constellation, possibly because this new way of looking at the stars enabled Greek sailors to more easily locate the north celestial pole.

But it’s not just our names for things in the sky that change. The sky itself changes, too. In our day, Polaris closely marks the north celestial pole in the sky. In 600 B.C. – thanks to the motion of precession – the stars Kochab and Pherkad more closely marked the position of the north celestial pole.

Kochab and Pherkad: Guardians of the Pole

The two outer stars in the bowl of the Big Dipper always point to Polaris, the North Star. Image by EarthSky Facebook friend Abhijit Juvekar.

Bottom line: Look for the Big and Little Dippers in the north at nightfall!

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

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

from EarthSky https://ift.tt/1ATscdS

Tonight, assuming you’re in the Northern Hemisphere, you can easily find the legendary Big Dipper, called The Plough by our friends in the U.K. or The Wagon throughout much of Europe. This familiar star pattern is high in the north at nightfall in June. Find it, and let it be your guide to the Little Dipper, too.

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

You can find the Big Dipper easily because its shape really resembles a dipper. Meanwhile, the Little Dipper isn’t as easy to find. You need a dark sky to see the Little Dipper, so be sure to avoid city lights.

How do you find the Dippers? Assuming you’re in the Northern Hemisphere, simply face northward on a June evening, and watch for a large dipper-like pattern. That easy-to-see pattern will be the Big Dipper. Notice that the Big Dipper has two parts: a bowl and a handle. See the two outer stars in the bowl? They’re known as The Pointers because they point to the North Star, which is also known as Polaris.

Once you’ve found Polaris, you can find the Little Dipper. Polaris marks the end of the handle of the Little Dipper. You need a dark night to see the Little Dipper in full, because it’s so much fainter than its larger and brighter counterpart.

By the way, can you see the Big Dipper from Earth’s Southern Hemisphere? Yes, if you’re in the southern tropics. Much farther south, and it gets harder; as you go southward on Earth’s globe, the Dipper sinks closer and closer to the northern horizon.

Meanwhile, Polaris, the North Star, disappears beneath the horizon once you get south of the Earth’s equator.

The Big and Little Dippers aren’t constellations. They’re asterisms, or noticeable star patterns. The Big Dipper is part of Ursa Major the Greater Bear. The Little Dipper belongs to Ursa Minor the Lesser Bear. Image via Dill Knob Observatory.

Richard Hinkley Allen in his book Star Names: Their Lore and Meaning claims the Greek constellation Ursa Minor was never mentioned in the literary works of Homer (9th century B.C.) or Hesiod (8th century B.C.). That’s probably because this constellation hadn’t been invented yet, that long ago.

According to the Greek geographer and historian Strabo (63 B.C. to A.D. 21?), the seven stars we see today as part of Ursa Minor (the Little Dipper) didn’t carry that name until 600 B.C. or so. Before that time, people saw this group of stars outlining the wings of the constellation Draco the Dragon.

When the seafaring Phoenicians visited the Greek philosopher Thales around 600 B.C., they showed him how to navigate by the stars. Purportedly, Thales clipped the Dragon’s wings to create a new constellation, possibly because this new way of looking at the stars enabled Greek sailors to more easily locate the north celestial pole.

But it’s not just our names for things in the sky that change. The sky itself changes, too. In our day, Polaris closely marks the north celestial pole in the sky. In 600 B.C. – thanks to the motion of precession – the stars Kochab and Pherkad more closely marked the position of the north celestial pole.

Kochab and Pherkad: Guardians of the Pole

The two outer stars in the bowl of the Big Dipper always point to Polaris, the North Star. Image by EarthSky Facebook friend Abhijit Juvekar.

Bottom line: Look for the Big and Little Dippers in the north at nightfall!

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

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

from EarthSky https://ift.tt/1ATscdS

Guatemala’s Fuego volcano erupts in fury

Fuego volcano moment of eruption – June 3, 2018 – via @MLopezSanMartin on Twitter.

Guatemala’s President Jimmy Morales has declared three days of national mourning after Sunday’s eruption of Volcan de Fuego, one of Central America’s most active volcanoes. According to media reports, it is the most powerful eruption since 1974. The eruption killed at least 25 people and injured many more. It spewed a river of hot lava that cut directly through the village of El Rodeo, at the foot of the volcano, burying the town and caused some deaths. Later, 18 bodies are said to have been found in the village of San Miguel Los Lotes. Meanwhile, the volcano belched thick, black smoke nearly six miles (10 km) into the air. Fleeing residents became covered in ash, and ash drifted the 27-mile (44-km) distance to Guatemala City, Guatemala’s capitol. More than 3,000 people were forced from their homes, according to media reports. The CONRED, Guatemala’s government agency for disaster relief, released a video of the event in which Consuelo Hernandez said:

Not everyone escaped, I think they were buried. We saw the lava was pouring through the corn fields and we ran toward a hill.

Rescue workers were hampered when roads were cut by the lava flows. The ash forced the closure of La Aurora International Airport, where the military assisted in clearing ash off of the runway.

Fuego volcano is famous for being almost constantly active at a low level. Small gas and ash eruptions occur every 15 to 20 minutes, but larger eruptions are rare. However, the volcano has been in a more active period since 2002.

The tweets below are from PNC Guatemala (@PNCdeGuatemala on Twitter), the national civil police force. If you click on each tweet, you will find an enlarged view, with a translation button below the tweets. They tell part of the story of yesterday’s dramatic events in Guatemala.

La mística de servicio impulsa a nuestros agentes de Policía Nacional Civil de Escuintla y Sacatepéquez a mantenerse firmes en las comunidades aledañas al Volcán de Fuego, que este día tuvo una actividad histórica. Vea usted estas imágenes. pic.twitter.com/gbs3cwSJFa

— PNC Guatemala (@PNCdeGuatemala) June 3, 2018

En estos momentos, nuestros agentes policiales contribuyen a la evacuación de una persona herida. Es un sobreviviente que fue localizado entre los escombros de una vivienda. Fue trasladado hacia un hospital. pic.twitter.com/efG4dDgVKV

— PNC Guatemala (@PNCdeGuatemala) June 3, 2018

Nuestra presencia policial es constante y sin claudicar esfuerzos en las aldeas El Rodeo, El Zapote, San Felipe, San José los Lotes, finca Sabana Grande, Escuintla. Nuestra institución policial en coordinación con Bomberos Voluntarios ha evacuado a 300 personas. pic.twitter.com/lcHmnQjNX4

— PNC Guatemala (@PNCdeGuatemala) June 3, 2018

#PNCProtegerYServir Elementos de nuestra Policía Nacional Civil continúan en la búsqueda y rescate de personas que han resultado damnificadas por el #VolcánDeFuego en la aldea El Rodeo en Escuintla. Hasta el momento han rescatado a niños y adultos pic.twitter.com/JxOdkl0xih

— PNC Guatemala (@PNCdeGuatemala) June 4, 2018

momento en que hace ERUPCIÓN el #VolcánDeFuego en #Guatemala

? pic.twitter.com/3IX0mu8bmT

— Manuel LopezSnMartin (@MLopezSanMartin) June 4, 2018

Bottom line:

from EarthSky https://ift.tt/2Jru5an

Fuego volcano moment of eruption – June 3, 2018 – via @MLopezSanMartin on Twitter.

Guatemala’s President Jimmy Morales has declared three days of national mourning after Sunday’s eruption of Volcan de Fuego, one of Central America’s most active volcanoes. According to media reports, it is the most powerful eruption since 1974. The eruption killed at least 25 people and injured many more. It spewed a river of hot lava that cut directly through the village of El Rodeo, at the foot of the volcano, burying the town and caused some deaths. Later, 18 bodies are said to have been found in the village of San Miguel Los Lotes. Meanwhile, the volcano belched thick, black smoke nearly six miles (10 km) into the air. Fleeing residents became covered in ash, and ash drifted the 27-mile (44-km) distance to Guatemala City, Guatemala’s capitol. More than 3,000 people were forced from their homes, according to media reports. The CONRED, Guatemala’s government agency for disaster relief, released a video of the event in which Consuelo Hernandez said:

Not everyone escaped, I think they were buried. We saw the lava was pouring through the corn fields and we ran toward a hill.

Rescue workers were hampered when roads were cut by the lava flows. The ash forced the closure of La Aurora International Airport, where the military assisted in clearing ash off of the runway.

Fuego volcano is famous for being almost constantly active at a low level. Small gas and ash eruptions occur every 15 to 20 minutes, but larger eruptions are rare. However, the volcano has been in a more active period since 2002.

The tweets below are from PNC Guatemala (@PNCdeGuatemala on Twitter), the national civil police force. If you click on each tweet, you will find an enlarged view, with a translation button below the tweets. They tell part of the story of yesterday’s dramatic events in Guatemala.

La mística de servicio impulsa a nuestros agentes de Policía Nacional Civil de Escuintla y Sacatepéquez a mantenerse firmes en las comunidades aledañas al Volcán de Fuego, que este día tuvo una actividad histórica. Vea usted estas imágenes. pic.twitter.com/gbs3cwSJFa

— PNC Guatemala (@PNCdeGuatemala) June 3, 2018

En estos momentos, nuestros agentes policiales contribuyen a la evacuación de una persona herida. Es un sobreviviente que fue localizado entre los escombros de una vivienda. Fue trasladado hacia un hospital. pic.twitter.com/efG4dDgVKV

— PNC Guatemala (@PNCdeGuatemala) June 3, 2018

Nuestra presencia policial es constante y sin claudicar esfuerzos en las aldeas El Rodeo, El Zapote, San Felipe, San José los Lotes, finca Sabana Grande, Escuintla. Nuestra institución policial en coordinación con Bomberos Voluntarios ha evacuado a 300 personas. pic.twitter.com/lcHmnQjNX4

— PNC Guatemala (@PNCdeGuatemala) June 3, 2018

#PNCProtegerYServir Elementos de nuestra Policía Nacional Civil continúan en la búsqueda y rescate de personas que han resultado damnificadas por el #VolcánDeFuego en la aldea El Rodeo en Escuintla. Hasta el momento han rescatado a niños y adultos pic.twitter.com/JxOdkl0xih

— PNC Guatemala (@PNCdeGuatemala) June 4, 2018

momento en que hace ERUPCIÓN el #VolcánDeFuego en #Guatemala

? pic.twitter.com/3IX0mu8bmT

— Manuel LopezSnMartin (@MLopezSanMartin) June 4, 2018

Bottom line:

from EarthSky https://ift.tt/2Jru5an

These distant moons may harbor life

Artist’s concept of a potentially habitable exomoon orbiting a giant planet in a distant solar system. Image via NASA GSFC: Jay Friedlander and Britt Griswold/ UCR.

The search for tell-tale biosignatures – signs that distant life is affecting its planet’s atmosphere – is a next step in exoplanet research. We don’t mean biosignatures from alien intelligences, necessarily. Any form of life, including microbial life, might chemically alter its planet’s atmosphere. Biosignature studies are often mentioned in connection with the James Webb Space Telescope – Hubble’s successor – currently due to launch in 2020. Late last month (May 30, 2018) – in preparation for future biosignature searches by the Webb and other future telescopes – researchers at the University of California, Riverside and the University of Southern Queensland announced they’ve identified 121 giant exoplanets with orbits within the habitable zone – zone within which liquid water can exist – of their stars. Although no exomoons are yet known for these planets, it’s likely some exomoons do exist. Some might have atmospheres. Some might be supporting life, whose biosignatures we can detect.

The new study (online here) has been accepted for publication in the peer-reviewed Astrophysical Journal.

Wait. We don’t know of any exomoons, and yet we’re planning to study them? Consider that it wasn’t until 1995 that the star 51 Pegasi went down in history as the first main-sequence star – or star in the same stage of its evolution as our sun – known to have a planet. Now, astronomers know of thousands of exoplanets and exoplanet candidates. The discovery of exomoons is surely on the horizon. Astronomer Stephen Kane at UC Riverside – a co-author on the new research – said:

There are currently 175 known moons orbiting the eight planets in our solar system. While most of these moons orbit Saturn and Jupiter, which are outside the sun’s habitable zone, that may not be the case in other solar systems. Including rocky exomoons in our search for life in space will greatly expand the places we can look.

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View larger. | The Habitable Zone. Shown is temperature vs starlight received. Important exoplanets are placed on the diagram, plus Earth, Venus, and Mars. Image via Chester Harman/ Wikimedia Commons.

The astronomers who conducted this study said their work will help guide the design of future telescopes that can detect exomoons. They pointed out that exomoons might provide a favorable environment for life, perhaps even better than Earth. That’s because they receive energy not only from their star, but also from radiation reflected from their planet.

Michelle Hill, an undergraduate student at the University of Southern Queensland who is working with Kane and will join UCR’s graduate program in the fall, was lead author on the new research. She commented:

Now that we have created a database of the known giant planets in the habitable zone of their star, observations of the best candidates for hosting potential exomoons will be made to help refine the expected exomoon properties. Our follow-up studies will help inform future telescope design so that we can detect these moons, study their properties, and look for signs of life.

Bottom line: Researchers in California and Australia say they’ve identified 121 giant planets whose moons might be capable of supporting life.

Source: Exploring Kepler Giant Planets in the Habitable Zone

Via URC

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Artist’s concept of a potentially habitable exomoon orbiting a giant planet in a distant solar system. Image via NASA GSFC: Jay Friedlander and Britt Griswold/ UCR.

The search for tell-tale biosignatures – signs that distant life is affecting its planet’s atmosphere – is a next step in exoplanet research. We don’t mean biosignatures from alien intelligences, necessarily. Any form of life, including microbial life, might chemically alter its planet’s atmosphere. Biosignature studies are often mentioned in connection with the James Webb Space Telescope – Hubble’s successor – currently due to launch in 2020. Late last month (May 30, 2018) – in preparation for future biosignature searches by the Webb and other future telescopes – researchers at the University of California, Riverside and the University of Southern Queensland announced they’ve identified 121 giant exoplanets with orbits within the habitable zone – zone within which liquid water can exist – of their stars. Although no exomoons are yet known for these planets, it’s likely some exomoons do exist. Some might have atmospheres. Some might be supporting life, whose biosignatures we can detect.

The new study (online here) has been accepted for publication in the peer-reviewed Astrophysical Journal.

Wait. We don’t know of any exomoons, and yet we’re planning to study them? Consider that it wasn’t until 1995 that the star 51 Pegasi went down in history as the first main-sequence star – or star in the same stage of its evolution as our sun – known to have a planet. Now, astronomers know of thousands of exoplanets and exoplanet candidates. The discovery of exomoons is surely on the horizon. Astronomer Stephen Kane at UC Riverside – a co-author on the new research – said:

There are currently 175 known moons orbiting the eight planets in our solar system. While most of these moons orbit Saturn and Jupiter, which are outside the sun’s habitable zone, that may not be the case in other solar systems. Including rocky exomoons in our search for life in space will greatly expand the places we can look.

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

View larger. | The Habitable Zone. Shown is temperature vs starlight received. Important exoplanets are placed on the diagram, plus Earth, Venus, and Mars. Image via Chester Harman/ Wikimedia Commons.

The astronomers who conducted this study said their work will help guide the design of future telescopes that can detect exomoons. They pointed out that exomoons might provide a favorable environment for life, perhaps even better than Earth. That’s because they receive energy not only from their star, but also from radiation reflected from their planet.

Michelle Hill, an undergraduate student at the University of Southern Queensland who is working with Kane and will join UCR’s graduate program in the fall, was lead author on the new research. She commented:

Now that we have created a database of the known giant planets in the habitable zone of their star, observations of the best candidates for hosting potential exomoons will be made to help refine the expected exomoon properties. Our follow-up studies will help inform future telescope design so that we can detect these moons, study their properties, and look for signs of life.

Bottom line: Researchers in California and Australia say they’ve identified 121 giant planets whose moons might be capable of supporting life.

Source: Exploring Kepler Giant Planets in the Habitable Zone

Via URC

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

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

Can you see better than your dog, cat, or goldfish?

A household scene as viewed by various pets and pests. Human eyesight is roughly 7 times sharper than a cat’s, 40 to 60 times sharper than a rat’s or a goldfish’s, and hundreds of times sharper than a fly’s or a mosquito’s. Image via Eleanor Caves.

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By Robin A.Smith/Duke University

Compared with many animals, human eyes aren’t particularly adept at distinguishing colors or seeing in dim light. But by one measure at least – something called visual acuity – commonly referred to as clarity of vision – human eyes can see fine details that most animals can’t. That’s according to a new study of animal vision that compared hundreds of species by the sharpness of their sight.

In a paper published in the May 2018 issue of the journal Trends in Ecology & Evolution, the researchers compiled previously published estimates of visual acuity for roughly 600 species of insects, birds, mammals, fish and other animals.

Eleanor Caves, a postdoctoral researcher at Duke University, is the study’s first author. She said that across the animal kingdom,

… Most species see the world with much less detail than we do.

Scientists compared hundreds of species by the sharpness of their sight. They found a 10,000-fold difference between the most sharp-sighted and the most blurry-eyed species, with humans ranking near the top. Image via Eugene Oliver.

The study measured acuity in terms of cycles per degree – that’s how many pairs of black and white parallel lines a species can discern within one degree of the field of vision before they turn into a smear of gray.

Researchers can’t ask a camel to identify letters on an eye chart. Instead, they estimate visual acuity based on an animal’s eye anatomy – such as the spacing and density of light-sensing structures – or using behavioral tests.

The limit of detail that human eyes can resolve is about 60 cycles per degree, which helps us make out road signs and recognize faces from afar. Chimpanzees and other primates can pick out similarly fine patterns.

A few birds of prey do better. For instance, the wedge-tailed eagle of Australia can see 140 cycles per degree, more than twice the limit of human visual acuity. Eagles can spot something as small as a rabbit while flying thousands of feet above the ground.

But apart from some eagles, vultures and falcons, the results show that most birds see fewer than 30 cycles per degree – less than half as much detail as humans. The same goes for fish. Caves said:

The highest acuity in a fish is still only about half as sharp as us.

Humans can resolve four to seven times more detail than dogs and cats, and more than a hundred times more than a mouse or a fruit fly. A person who sees less than 10 cycles per degree is considered legally blind. Most insects, it turns out, can’t see more than one.

Overall, the researchers found a 10,000-fold difference between the most sharp-sighted and the most blurry-eyed species.

The researchers also created a series of images showing how different scenes might appear to animals with different acuities, using a software package they developed called AcuityView. The software takes a digital photo and strips away all the spatial detail that may be too fine for a given animal to distinguish.

The image on the left shows the wings of a map butterfly as they might look to a jay looking for a snack, and on the right, to another member of its kind, such as a rival or potential mate. Image via Eleanor Caves.

The converted images reveal animal patterns that, while easy for some species to see, may be imperceptible to others, or only recognizable from a short distance.

Take the patterns on a butterfly’s wing. Scientists have debated the function of their spots, stripes and splotches. One common assumption is that they warn birds and other predators to stay away. It has also been proposed that they help butterflies check out or seduce potential mates.

The researchers determined that the wing patterns of, say, the map butterfly may be apparent to many birds, but to others of their kind their wing patterns are likely a blur, even from just a few inches away. Caves said:

I don’t actually think butterflies can see them.

A spider web as seen in bird vision (left), and fly vision (right). The zigzags on the spider’s web send a secret message to birds that their insect prey can’t see, even from less than a foot away. Image via Eleanor Caves.

Some animals may use such differences in acuity to send secret messages that sharper-sighted species can read but others can’t, Caves said. For instance, orb-weaver spiders decorate their webs with white silk zigzags, spirals and other designs whose function has been debated. One theory is that they keep larger animals from accidentally colliding with their delicate webs, like the window stickers used to keep birds from flying into the glass. Another idea is that they lure insect prey.

But images of spider web decorations as they might appear to different species suggest that, while birds can spot them from as far away as six feet, they are virtually invisible to houseflies and other small insects that might blunder into the spider’s sticky traps.

It seems the decorations help spiders alert birds to webs that might be in their flight path, without blowing their cover with the creatures they might be trying to catch for lunch.

The converted images the team produced don’t represent what animals actually see, the researchers caution. That’s because while the eyes take in visual information, the brain must make sense of it.

It is likely that certain things may be sharper or easier to detect thanks to edge enhancement and other forms of “post-processing” that occur once the visual information is relayed to the brain, Caves said. But the software gives researchers a sense of what visual information the brain has to work with. Caves said:

The point is that researchers who study animal interactions shouldn’t assume that different species perceive detail the same way we do.

Bottom line: A new study looks at how human eyesight compares to the vision of other animals and insects.

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

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

A household scene as viewed by various pets and pests. Human eyesight is roughly 7 times sharper than a cat’s, 40 to 60 times sharper than a rat’s or a goldfish’s, and hundreds of times sharper than a fly’s or a mosquito’s. Image via Eleanor Caves.

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

By Robin A.Smith/Duke University

Compared with many animals, human eyes aren’t particularly adept at distinguishing colors or seeing in dim light. But by one measure at least – something called visual acuity – commonly referred to as clarity of vision – human eyes can see fine details that most animals can’t. That’s according to a new study of animal vision that compared hundreds of species by the sharpness of their sight.

In a paper published in the May 2018 issue of the journal Trends in Ecology & Evolution, the researchers compiled previously published estimates of visual acuity for roughly 600 species of insects, birds, mammals, fish and other animals.

Eleanor Caves, a postdoctoral researcher at Duke University, is the study’s first author. She said that across the animal kingdom,

… Most species see the world with much less detail than we do.

Scientists compared hundreds of species by the sharpness of their sight. They found a 10,000-fold difference between the most sharp-sighted and the most blurry-eyed species, with humans ranking near the top. Image via Eugene Oliver.

The study measured acuity in terms of cycles per degree – that’s how many pairs of black and white parallel lines a species can discern within one degree of the field of vision before they turn into a smear of gray.

Researchers can’t ask a camel to identify letters on an eye chart. Instead, they estimate visual acuity based on an animal’s eye anatomy – such as the spacing and density of light-sensing structures – or using behavioral tests.

The limit of detail that human eyes can resolve is about 60 cycles per degree, which helps us make out road signs and recognize faces from afar. Chimpanzees and other primates can pick out similarly fine patterns.

A few birds of prey do better. For instance, the wedge-tailed eagle of Australia can see 140 cycles per degree, more than twice the limit of human visual acuity. Eagles can spot something as small as a rabbit while flying thousands of feet above the ground.

But apart from some eagles, vultures and falcons, the results show that most birds see fewer than 30 cycles per degree – less than half as much detail as humans. The same goes for fish. Caves said:

The highest acuity in a fish is still only about half as sharp as us.

Humans can resolve four to seven times more detail than dogs and cats, and more than a hundred times more than a mouse or a fruit fly. A person who sees less than 10 cycles per degree is considered legally blind. Most insects, it turns out, can’t see more than one.

Overall, the researchers found a 10,000-fold difference between the most sharp-sighted and the most blurry-eyed species.

The researchers also created a series of images showing how different scenes might appear to animals with different acuities, using a software package they developed called AcuityView. The software takes a digital photo and strips away all the spatial detail that may be too fine for a given animal to distinguish.

The image on the left shows the wings of a map butterfly as they might look to a jay looking for a snack, and on the right, to another member of its kind, such as a rival or potential mate. Image via Eleanor Caves.

The converted images reveal animal patterns that, while easy for some species to see, may be imperceptible to others, or only recognizable from a short distance.

Take the patterns on a butterfly’s wing. Scientists have debated the function of their spots, stripes and splotches. One common assumption is that they warn birds and other predators to stay away. It has also been proposed that they help butterflies check out or seduce potential mates.

The researchers determined that the wing patterns of, say, the map butterfly may be apparent to many birds, but to others of their kind their wing patterns are likely a blur, even from just a few inches away. Caves said:

I don’t actually think butterflies can see them.

A spider web as seen in bird vision (left), and fly vision (right). The zigzags on the spider’s web send a secret message to birds that their insect prey can’t see, even from less than a foot away. Image via Eleanor Caves.

Some animals may use such differences in acuity to send secret messages that sharper-sighted species can read but others can’t, Caves said. For instance, orb-weaver spiders decorate their webs with white silk zigzags, spirals and other designs whose function has been debated. One theory is that they keep larger animals from accidentally colliding with their delicate webs, like the window stickers used to keep birds from flying into the glass. Another idea is that they lure insect prey.

But images of spider web decorations as they might appear to different species suggest that, while birds can spot them from as far away as six feet, they are virtually invisible to houseflies and other small insects that might blunder into the spider’s sticky traps.

It seems the decorations help spiders alert birds to webs that might be in their flight path, without blowing their cover with the creatures they might be trying to catch for lunch.

The converted images the team produced don’t represent what animals actually see, the researchers caution. That’s because while the eyes take in visual information, the brain must make sense of it.

It is likely that certain things may be sharper or easier to detect thanks to edge enhancement and other forms of “post-processing” that occur once the visual information is relayed to the brain, Caves said. But the software gives researchers a sense of what visual information the brain has to work with. Caves said:

The point is that researchers who study animal interactions shouldn’t assume that different species perceive detail the same way we do.

Bottom line: A new study looks at how human eyesight compares to the vision of other animals and insects.

Help EarthSky keep going! Please donate what you can to our annual crowd-funding campaign.

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

Shelf cloud over Florida

Shelf cloud bringing rain or Ormond Beach, Florida on June 1, 2018. Rita Addison wrote: “I watched it move over us, taking many pictures in stages. So excited … wanted to share.” Thanks Rita!

from EarthSky https://ift.tt/2kMbiJ9

Shelf cloud bringing rain or Ormond Beach, Florida on June 1, 2018. Rita Addison wrote: “I watched it move over us, taking many pictures in stages. So excited … wanted to share.” Thanks Rita!

from EarthSky https://ift.tt/2kMbiJ9