Giant planet HR 5183b would look 15 times brighter than Venus

Artist’s concept of Venus – brightest planet visible from Earth and a dazzling light low in the west after sunset now – in contrast the brightness of the giant planet in the distant star system HR 5183. Image via UC Riverside.

HR 5183b is an exoplanet – discovered earlier this year – orbiting a distant sun some 103 light-years away in the direction to our constellation Virgo the Maiden. The planet has at least 3 times the mass of Jupiter, our solar system’s most massive and biggest world. Even more interestingly, the giant exoplanet HR 5183b has a highly eccentric orbit. If its orbit were placed within our solar system, this huge world would travel closer to the sun than Jupiter, then swing outward again beyond the orbit of Neptune. Its wild orbit gave it the nickname of the whiplash planet. Shortly after its discovery, astronomers said such a large planet in such an orbit precluded the presence of an Earth-like planet in the same solar system. But a new study – led by astronomer Stephen Kane at University of California Riverside and published in The Astronomical Journal on October 31 – suggests otherwise. According to the authors of the new study:

Our results show that, despite the incredible perturbing influence of the giant planet, there remain a narrow range of locations within the habitable zone [the realm of a solar system within which liquid water can exist] where terrestrial planets [planets like Earth] may reside in long-term stable orbits.

In other words, the star system HR 5183 could have an Earth-like planet in it, and that planet could harbor life.

That’s interesting. And it’s also tantalizing to realize what an living beings on such a planet would see in their sky. HR 5813b, the eccentric giant in Kane’s study, takes nearly 75 years to orbit its star. But the moment this giant finally swings past its smaller neighbor would be a breathtaking, once-in-a-lifetime event. Kane explained:

When the giant is at its closest approach to the Earth-like planet, it would be 15 times brighter than Venus — one of the brightest objects visible with the unaided eye. It would dominate the night sky.

View at EarthSky Community Photos. | Here’s an actual photo of Mercury (far left), Venus (middle) and the moon on a recent evening (October 29, 2019). Imagine seeing HR 5183b in this scene? As the artist’s concept at the top of this post shows, it’d be much brighter than Venus! Image via Asger Mollerup at Phu Lan Chang Mountain in the Khao Wong Valley, northeast Thailand. Thank you, Asger!

The planets in our solar system also have eccentric orbits; but they’re not highly eccentric. Instead, they’re very nearly circular. A statement from UC Riverside explained:

Conventional wisdom says that a giant planet in eccentric orbit is like a wrecking ball for its planetary neighbors, making them unstable, upsetting weather systems, and reducing or eliminating the likelihood of life existing on them.

Questioning this assumption, Kane and Caltech astronomer Sarah Blunt (@SarahCBlunt on Twitter) tested the stability of an Earth-like planet in the HR 5183 solar system … Kane and Blunt calculated the giant planet’s gravitational pull on an Earth analog as they both orbited their star.

Kane continued:

In these simulations, the giant planet often had a catastrophic effect on the Earth twin, in many cases throwing it out of the solar system entirely. But in certain parts of the planetary system, the gravitational effect of the giant planet is remarkably small enough to allow the Earth-like planet to remain in a stable orbit.

The team found that the smaller, terrestrial planet has the best chance of remaining stable within an area of the solar system called the habitable zone — which is the territory around a star that is warm enough to allow for liquid-water oceans on a planet.

These findings not only increase the number of places where life might exist in the solar system described in this study — they increase the number of places in the universe that could potentially host life as we know it.

Read more via UC Riverside: The most spectacular celestial vision you’ll never see

Comparison of HR 5183b’s eccentric orbit to the more circular orbits of the planets in our own solar system. Image via W. M. Keck Observatory/ Adam Makarenko/ UC Riverside.

Bottom line: Earlier this year, astronomers discovered a huge planet in a highly eccentric orbit, orbiting the star HR 5183, located 103 light-years away. The presence of such a planet was thought to preclude stable orbits for Earth-like planets in the same system. A new study shows – on the contrary – that Earth-like worlds can exist in this system. If one does, and if it’s inhabited, its citizens will witness a spectacular event every 75 years, whenever the giant planet HR 5183b is closest to its star. At such times, the giant planet would appear unlike anything we’ve ever seen, 15 times brighter in the sky than Venus!

Source: In the Presence of a Wrecking Ball: Orbital Stability in the HR 5183 System

from EarthSky https://ift.tt/33kud2b

Artist’s concept of Venus – brightest planet visible from Earth and a dazzling light low in the west after sunset now – in contrast the brightness of the giant planet in the distant star system HR 5183. Image via UC Riverside.

HR 5183b is an exoplanet – discovered earlier this year – orbiting a distant sun some 103 light-years away in the direction to our constellation Virgo the Maiden. The planet has at least 3 times the mass of Jupiter, our solar system’s most massive and biggest world. Even more interestingly, the giant exoplanet HR 5183b has a highly eccentric orbit. If its orbit were placed within our solar system, this huge world would travel closer to the sun than Jupiter, then swing outward again beyond the orbit of Neptune. Its wild orbit gave it the nickname of the whiplash planet. Shortly after its discovery, astronomers said such a large planet in such an orbit precluded the presence of an Earth-like planet in the same solar system. But a new study – led by astronomer Stephen Kane at University of California Riverside and published in The Astronomical Journal on October 31 – suggests otherwise. According to the authors of the new study:

Our results show that, despite the incredible perturbing influence of the giant planet, there remain a narrow range of locations within the habitable zone [the realm of a solar system within which liquid water can exist] where terrestrial planets [planets like Earth] may reside in long-term stable orbits.

In other words, the star system HR 5183 could have an Earth-like planet in it, and that planet could harbor life.

That’s interesting. And it’s also tantalizing to realize what an living beings on such a planet would see in their sky. HR 5813b, the eccentric giant in Kane’s study, takes nearly 75 years to orbit its star. But the moment this giant finally swings past its smaller neighbor would be a breathtaking, once-in-a-lifetime event. Kane explained:

When the giant is at its closest approach to the Earth-like planet, it would be 15 times brighter than Venus — one of the brightest objects visible with the unaided eye. It would dominate the night sky.

View at EarthSky Community Photos. | Here’s an actual photo of Mercury (far left), Venus (middle) and the moon on a recent evening (October 29, 2019). Imagine seeing HR 5183b in this scene? As the artist’s concept at the top of this post shows, it’d be much brighter than Venus! Image via Asger Mollerup at Phu Lan Chang Mountain in the Khao Wong Valley, northeast Thailand. Thank you, Asger!

The planets in our solar system also have eccentric orbits; but they’re not highly eccentric. Instead, they’re very nearly circular. A statement from UC Riverside explained:

Conventional wisdom says that a giant planet in eccentric orbit is like a wrecking ball for its planetary neighbors, making them unstable, upsetting weather systems, and reducing or eliminating the likelihood of life existing on them.

Questioning this assumption, Kane and Caltech astronomer Sarah Blunt (@SarahCBlunt on Twitter) tested the stability of an Earth-like planet in the HR 5183 solar system … Kane and Blunt calculated the giant planet’s gravitational pull on an Earth analog as they both orbited their star.

Kane continued:

In these simulations, the giant planet often had a catastrophic effect on the Earth twin, in many cases throwing it out of the solar system entirely. But in certain parts of the planetary system, the gravitational effect of the giant planet is remarkably small enough to allow the Earth-like planet to remain in a stable orbit.

The team found that the smaller, terrestrial planet has the best chance of remaining stable within an area of the solar system called the habitable zone — which is the territory around a star that is warm enough to allow for liquid-water oceans on a planet.

These findings not only increase the number of places where life might exist in the solar system described in this study — they increase the number of places in the universe that could potentially host life as we know it.

Read more via UC Riverside: The most spectacular celestial vision you’ll never see

Comparison of HR 5183b’s eccentric orbit to the more circular orbits of the planets in our own solar system. Image via W. M. Keck Observatory/ Adam Makarenko/ UC Riverside.

Bottom line: Earlier this year, astronomers discovered a huge planet in a highly eccentric orbit, orbiting the star HR 5183, located 103 light-years away. The presence of such a planet was thought to preclude stable orbits for Earth-like planets in the same system. A new study shows – on the contrary – that Earth-like worlds can exist in this system. If one does, and if it’s inhabited, its citizens will witness a spectacular event every 75 years, whenever the giant planet HR 5183b is closest to its star. At such times, the giant planet would appear unlike anything we’ve ever seen, 15 times brighter in the sky than Venus!

Source: In the Presence of a Wrecking Ball: Orbital Stability in the HR 5183 System

from EarthSky https://ift.tt/33kud2b

Voyager 2 sends back insights on interstellar space

View a larger, annotated image. | Look closely at the blue ball. Inside you’ll see a yellow dot representing our sun, and some white ovals representing the orbits of the planets orbiting our sun, including Earth. The lighter blue oval represents the heliosphere, or realm of the sun’s influence, as our sun moves through the space of the Milky Way galaxy. In this artist’s depiction, Voyagers 1 and 2 – launched from Earth in 1977 – are depicted just outside of the heliosphere, on the boundary of interstellar space. The image – not to scale – is via NASA. Both spacecraft are still heading outward …

Voyager 1 crossed the heliopause, or the edge of the heliosphere – the protective bubble of particles and magnetic fields created by our sun – in August 2012. Heading in a different direction, Voyager 2 crossed another part of the heliopause on today’s date a year ago, November 5, 2018. Thus Voyager 2 became only the second earthly spacecraft to cross into interstellar space, at a distance of some 11 billion miles (18 billion km) from Earth, well beyond the orbit of Pluto. Today, five new research papers in the peer-reviewed journal Nature Astronomy describe what scientists observed during and since Voyager 2’s historic crossing (see links to the papers below). A statement from NASA said:

Each paper details the findings from one of Voyager 2’s five operating science instruments: a magnetic field sensor, two instruments to detect energetic particles in different energy ranges and two instruments for studying plasma (a gas composed of charged particles). Taken together, the findings help paint a picture of this cosmic shoreline, where the environment created by our sun ends and the vast ocean of interstellar space begins.

Before their historic crossing into interstellar space, the Voyagers had already served humanity well. Taking advantage of a rare alignment of planets in the outer solar system, both Voyagers visited mighty Jupiter and ringed Saturn, and Voyager 2 performed the first – and only – flybys of the ice giants Uranus and Neptune.

Consider that – before Voyager 1 reached the edge of the heliosphere in 2012 – this edge was entirely theoretical in nature. We had never been to the boundary of interstellar space before. Scientists weren’t entirely sure how far this boundary was located from our sun, although their predictions turned out to be amazingly precise. You might know that the sun undergoes an 11-year cycle of activity. Scientists expected the heliopause – or boundary region of the heliosphere – to move with the changes in activity on the sun:

… sort of like a lung expanding and contracting with breath. This was consistent with the fact that the two probes encountered the heliopause at different distances from the sun.

And so – due to the malleable nature of the heliopause – the two Voyagers crossed into interstellar space at different times, one six years before the other, and at different distances from the sun. The new papers now confirm that Voyager 2 is not yet in undisturbed interstellar space. Like its twin, Voyager 1, Voyager 2 appears to be in a perturbed transitional region just beyond the heliosphere. Ed Stone, project scientist for Voyager and a professor of physics at Caltech, commented:

The Voyager probes are showing us how our sun interacts with the stuff that fills most of the space between stars in the Milky Way galaxy. Without this new data from Voyager 2, we wouldn’t know if what we were seeing with Voyager 1 was characteristic of the entire heliosphere or specific just to the location and time when it crossed.

EarthSky 2020 lunar calendars are available! They make great gifts. Order now. Going fast!

Both Voyagers carry a golden record, designed to give any alien civilization that might someday encounter the craft a glimpse of Earth and its abundant life. Read more from NASA about the making of the golden record.

The five new papers in Nature Astronomy describe various measurements made by Voyager 2. According to NASA:

The two Voyager spacecraft have now confirmed that the plasma in local interstellar space is significantly denser than the plasma inside the heliosphere, as scientists expected. Voyager 2 has now also measured the temperature of the plasma in nearby interstellar space and confirmed it is colder than the plasma inside the heliosphere.

In 2012, Voyager 1 observed a slightly higher-than-expected plasma density just outside the heliosphere, indicating that the plasma is being somewhat compressed. Voyager 2 observed that the plasma outside the heliosphere is slightly warmer than expected, which could also indicate it is being compressed. (The plasma outside is still colder than the plasma inside.) Voyager 2 also observed a slight increase in plasma density just before it exited the heliosphere, indicating that the plasma is compressed around the inside edge of the bubble. But scientists don’t yet fully understand what is causing the compression on either side.

Speaking of Voyager 2’s findings, NASA also said:

If the heliosphere is like a ship sailing through interstellar space, it appears the hull is somewhat leaky. One of Voyager’s particle instruments showed that a trickle of particles from inside the heliosphere is slipping through the boundary and into interstellar space. Voyager 1 exited close to the very ‘front’ of the heliosphere, relative to the bubble’s movement through space. Voyager 2, on the other hand, is located closer to the flank, and this region appears to be more porous than the region where Voyager 1 is located.

And NASA explained:

An observation by Voyager 2’s magnetic field instrument confirms a surprising result from Voyager 1: The magnetic field in the region just beyond the heliopause is parallel to the magnetic field inside the heliosphere. With Voyager 1, scientists had only one sample of these magnetic fields and couldn’t say for sure whether the apparent alignment was characteristic of the entire exterior region or just a coincidence. Voyager 2’s magnetometer observations confirm the Voyager 1 finding and indicate that the two fields align, according to Stone.

Voyager 1, the faster of the two probes, is currently over 13.6 billion miles (22 billion kilometers) from the sun.

Voyager 2 is 11.3 billion miles (18.2 billion kilometers) from the sun. Traveling at the speed of light, a signal from Voyager 2 requires about 16.5 hours to travel to Earth. By comparison, light traveling from the sun takes about eight minutes to reach Earth. The 22.4-watt transmitter on Voyager 2 has a power equivalent to the light that pops on when you open your refrigerator door. This dim signal from Voyager – which is more than a billion billion times dimmer by the time it reaches Earth – is picked up by the 70-meter antennas at three facilities spaced equidistant from each other – approximately 120 degrees apart in longitude – around the world. These are the sites of NASA’s Deep Space Network at Goldstone, near Barstow, California; near Madrid, Spain; and near Canberra, Australia.

The two Voyagers are powered by steadily decaying plutonium batteries. NASA scientists have been slowly powering down the crafts’ scientific instruments for some years now, attempting to stretch out the amount of time we can continue to communicate with them. Both craft are projected to drop below critical energy levels in the mid-2020s, after which they will fall silent.

In this artist’s concept, a Voyager spacecraft looks back toward our solar system, from its vantage point in interstellar space. The circles represent the orbits of the major outer planets, all visited by Voyager 2: Jupiter, Saturn, Uranus and Neptune. Image via NASA, ESA, and G. Bacon (STScI).

Bottom line: Voyager 2 crossed into interstellar space on November 5, 2018 – one year ago today – becoming the 2nd craft ever to do so. This week, the journal Nature Astronomy published 5 new papers describing what Voyager 2 has been seeing on its journey into the unknown.

Source: Voyager 2 plasma observations of the heliopause and interstellar medium

Source: Cosmic ray measurements from Voyager 2 as it crossed into interstellar space

Source: Magnetic field and particle measurements made by Voyager 2 at and near the heliopause

Source: Energetic charged particle measurements from Voyager 2 at the heliopause and beyond

Source: Plasma densities near and beyond the heliopause from the Voyager 1 and 2 plasma wave instruments

Via NASA

from EarthSky https://ift.tt/32jEfiW

View a larger, annotated image. | Look closely at the blue ball. Inside you’ll see a yellow dot representing our sun, and some white ovals representing the orbits of the planets orbiting our sun, including Earth. The lighter blue oval represents the heliosphere, or realm of the sun’s influence, as our sun moves through the space of the Milky Way galaxy. In this artist’s depiction, Voyagers 1 and 2 – launched from Earth in 1977 – are depicted just outside of the heliosphere, on the boundary of interstellar space. The image – not to scale – is via NASA. Both spacecraft are still heading outward …

Voyager 1 crossed the heliopause, or the edge of the heliosphere – the protective bubble of particles and magnetic fields created by our sun – in August 2012. Heading in a different direction, Voyager 2 crossed another part of the heliopause on today’s date a year ago, November 5, 2018. Thus Voyager 2 became only the second earthly spacecraft to cross into interstellar space, at a distance of some 11 billion miles (18 billion km) from Earth, well beyond the orbit of Pluto. Today, five new research papers in the peer-reviewed journal Nature Astronomy describe what scientists observed during and since Voyager 2’s historic crossing (see links to the papers below). A statement from NASA said:

Each paper details the findings from one of Voyager 2’s five operating science instruments: a magnetic field sensor, two instruments to detect energetic particles in different energy ranges and two instruments for studying plasma (a gas composed of charged particles). Taken together, the findings help paint a picture of this cosmic shoreline, where the environment created by our sun ends and the vast ocean of interstellar space begins.

Before their historic crossing into interstellar space, the Voyagers had already served humanity well. Taking advantage of a rare alignment of planets in the outer solar system, both Voyagers visited mighty Jupiter and ringed Saturn, and Voyager 2 performed the first – and only – flybys of the ice giants Uranus and Neptune.

Consider that – before Voyager 1 reached the edge of the heliosphere in 2012 – this edge was entirely theoretical in nature. We had never been to the boundary of interstellar space before. Scientists weren’t entirely sure how far this boundary was located from our sun, although their predictions turned out to be amazingly precise. You might know that the sun undergoes an 11-year cycle of activity. Scientists expected the heliopause – or boundary region of the heliosphere – to move with the changes in activity on the sun:

… sort of like a lung expanding and contracting with breath. This was consistent with the fact that the two probes encountered the heliopause at different distances from the sun.

And so – due to the malleable nature of the heliopause – the two Voyagers crossed into interstellar space at different times, one six years before the other, and at different distances from the sun. The new papers now confirm that Voyager 2 is not yet in undisturbed interstellar space. Like its twin, Voyager 1, Voyager 2 appears to be in a perturbed transitional region just beyond the heliosphere. Ed Stone, project scientist for Voyager and a professor of physics at Caltech, commented:

The Voyager probes are showing us how our sun interacts with the stuff that fills most of the space between stars in the Milky Way galaxy. Without this new data from Voyager 2, we wouldn’t know if what we were seeing with Voyager 1 was characteristic of the entire heliosphere or specific just to the location and time when it crossed.

EarthSky 2020 lunar calendars are available! They make great gifts. Order now. Going fast!

Both Voyagers carry a golden record, designed to give any alien civilization that might someday encounter the craft a glimpse of Earth and its abundant life. Read more from NASA about the making of the golden record.

The five new papers in Nature Astronomy describe various measurements made by Voyager 2. According to NASA:

The two Voyager spacecraft have now confirmed that the plasma in local interstellar space is significantly denser than the plasma inside the heliosphere, as scientists expected. Voyager 2 has now also measured the temperature of the plasma in nearby interstellar space and confirmed it is colder than the plasma inside the heliosphere.

In 2012, Voyager 1 observed a slightly higher-than-expected plasma density just outside the heliosphere, indicating that the plasma is being somewhat compressed. Voyager 2 observed that the plasma outside the heliosphere is slightly warmer than expected, which could also indicate it is being compressed. (The plasma outside is still colder than the plasma inside.) Voyager 2 also observed a slight increase in plasma density just before it exited the heliosphere, indicating that the plasma is compressed around the inside edge of the bubble. But scientists don’t yet fully understand what is causing the compression on either side.

Speaking of Voyager 2’s findings, NASA also said:

If the heliosphere is like a ship sailing through interstellar space, it appears the hull is somewhat leaky. One of Voyager’s particle instruments showed that a trickle of particles from inside the heliosphere is slipping through the boundary and into interstellar space. Voyager 1 exited close to the very ‘front’ of the heliosphere, relative to the bubble’s movement through space. Voyager 2, on the other hand, is located closer to the flank, and this region appears to be more porous than the region where Voyager 1 is located.

And NASA explained:

An observation by Voyager 2’s magnetic field instrument confirms a surprising result from Voyager 1: The magnetic field in the region just beyond the heliopause is parallel to the magnetic field inside the heliosphere. With Voyager 1, scientists had only one sample of these magnetic fields and couldn’t say for sure whether the apparent alignment was characteristic of the entire exterior region or just a coincidence. Voyager 2’s magnetometer observations confirm the Voyager 1 finding and indicate that the two fields align, according to Stone.

Voyager 1, the faster of the two probes, is currently over 13.6 billion miles (22 billion kilometers) from the sun.

Voyager 2 is 11.3 billion miles (18.2 billion kilometers) from the sun. Traveling at the speed of light, a signal from Voyager 2 requires about 16.5 hours to travel to Earth. By comparison, light traveling from the sun takes about eight minutes to reach Earth. The 22.4-watt transmitter on Voyager 2 has a power equivalent to the light that pops on when you open your refrigerator door. This dim signal from Voyager – which is more than a billion billion times dimmer by the time it reaches Earth – is picked up by the 70-meter antennas at three facilities spaced equidistant from each other – approximately 120 degrees apart in longitude – around the world. These are the sites of NASA’s Deep Space Network at Goldstone, near Barstow, California; near Madrid, Spain; and near Canberra, Australia.

The two Voyagers are powered by steadily decaying plutonium batteries. NASA scientists have been slowly powering down the crafts’ scientific instruments for some years now, attempting to stretch out the amount of time we can continue to communicate with them. Both craft are projected to drop below critical energy levels in the mid-2020s, after which they will fall silent.

In this artist’s concept, a Voyager spacecraft looks back toward our solar system, from its vantage point in interstellar space. The circles represent the orbits of the major outer planets, all visited by Voyager 2: Jupiter, Saturn, Uranus and Neptune. Image via NASA, ESA, and G. Bacon (STScI).

Bottom line: Voyager 2 crossed into interstellar space on November 5, 2018 – one year ago today – becoming the 2nd craft ever to do so. This week, the journal Nature Astronomy published 5 new papers describing what Voyager 2 has been seeing on its journey into the unknown.

Source: Voyager 2 plasma observations of the heliopause and interstellar medium

Source: Cosmic ray measurements from Voyager 2 as it crossed into interstellar space

Source: Magnetic field and particle measurements made by Voyager 2 at and near the heliopause

Source: Energetic charged particle measurements from Voyager 2 at the heliopause and beyond

Source: Plasma densities near and beyond the heliopause from the Voyager 1 and 2 plasma wave instruments

Via NASA

from EarthSky https://ift.tt/32jEfiW

Sky Bear comes to Earth in November

Tonight … a constellation you might or might not see, depending on your latitude. In the Northern Hemisphere, the Big Dipper is probably the sky’s best known asterism. In other words, it’s a recognizable pattern of stars – not an official constellation. The Big Dipper is part of the constellation Ursa Major, otherwise known as the Great Bear.

Every year, the Big Dipper (Great Bear) descends to its lowest point in the sky on November evenings. In fact, people in the southern part of the United States can’t see the Big Dipper in the evening right now, because it swings beneath their northern horizon.

And, of course, it can’t be seen in the evening from Southern Hemisphere latitudes now either.

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Image via AlltheSky.com.

Even in the northern states, the Big Bear is hard to spot. The Big Dipper skims along the northern horizon in the evening, ducking behind any obstructions – such as trees and mountains.

To the Micmac Indians living in southeast Canada, a Celestial Bear – our same familiar Big Dipper pattern – coming down to Earth signaled the start of hibernation season. This is when earthly bears return to their dens, and when the sap of trees returns to the warm womb of the underworld. Weary creation tucks in, waiting for winter’s deep slumber.

The Micmacs saw the Big Dipper handle stars as hunters forever chasing Celestial Bear. In their sky lore, hunters catch Celestial Bear each year in the fall, and it’s the dripping blood from the Bear that colors the autumn landscape.

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View larger. | Another portrayal of the Big Dipper in November. It’s Vincent van Gogh’s Starry Night Over the Rhone, painted in September 1888 at Arles. Had you noticed the Big Dipper in this painting? Can you see it tonight?

Bottom line: The Big Dipper is difficult, or impossible, to see on November evenings. If you’re in the southern U.S. or a similar latitude around the world, the Dipper is below your northern horizon in the evening now. If you’re in the northern U.S. or a similar latitude, the Big Dipper may be above your horizon in the evening, but it will be low in the northern sky.

Donate: Your support means the world to us

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

Tonight … a constellation you might or might not see, depending on your latitude. In the Northern Hemisphere, the Big Dipper is probably the sky’s best known asterism. In other words, it’s a recognizable pattern of stars – not an official constellation. The Big Dipper is part of the constellation Ursa Major, otherwise known as the Great Bear.

Every year, the Big Dipper (Great Bear) descends to its lowest point in the sky on November evenings. In fact, people in the southern part of the United States can’t see the Big Dipper in the evening right now, because it swings beneath their northern horizon.

And, of course, it can’t be seen in the evening from Southern Hemisphere latitudes now either.

EarthSky lunar calendars are cool! They make great gifts. Order now. Going fast!

Image via AlltheSky.com.

Even in the northern states, the Big Bear is hard to spot. The Big Dipper skims along the northern horizon in the evening, ducking behind any obstructions – such as trees and mountains.

To the Micmac Indians living in southeast Canada, a Celestial Bear – our same familiar Big Dipper pattern – coming down to Earth signaled the start of hibernation season. This is when earthly bears return to their dens, and when the sap of trees returns to the warm womb of the underworld. Weary creation tucks in, waiting for winter’s deep slumber.

The Micmacs saw the Big Dipper handle stars as hunters forever chasing Celestial Bear. In their sky lore, hunters catch Celestial Bear each year in the fall, and it’s the dripping blood from the Bear that colors the autumn landscape.

Donate: Your support means the world to us

View larger. | Another portrayal of the Big Dipper in November. It’s Vincent van Gogh’s Starry Night Over the Rhone, painted in September 1888 at Arles. Had you noticed the Big Dipper in this painting? Can you see it tonight?

Bottom line: The Big Dipper is difficult, or impossible, to see on November evenings. If you’re in the southern U.S. or a similar latitude around the world, the Dipper is below your northern horizon in the evening now. If you’re in the northern U.S. or a similar latitude, the Big Dipper may be above your horizon in the evening, but it will be low in the northern sky.

Donate: Your support means the world to us

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

1st quarter moon is November 4

View at EarthSky Community Photos. | Our friend Dr Ski in the Philippines caught this photo as night came to his part of the world, on November 4, 2019. He wrote: “The moon has reached 1st quarter and is visible on my side of the planet now.”

A first quarter moon rises around noon and sets around midnight. You’ll likely spot it in late afternoon or early evening, high up in the sky. At this moon phase, the moon is showing us precisely half of its lighted half. Or you might say that – at first quarter moon – we’re seeing half the moon’s day side.

We call this moon a quarter and not a half because it is one quarter of the way around in its orbit of Earth, as measured from one new moon to the next. Also, although a first quarter moon appears half-lit to us, the illuminated portion we see of a first quarter moon truly is just a quarter. We’re now seeing half the moon’s day side, that is. Another lighted quarter of the moon shines just as brightly in the direction opposite Earth!

And what about the term half moon? That’s a beloved term, but not an official one.

Read more: 4 keys to understanding moon phases

The lunar calendars are here! Get your 2020 lunar calendars today. They make great gifts. Going fast.

The 1st quarter moon comes on October 5, 2019, at 16:47 Universal Time (UTC). Then, some four hours later, the moon passes 0.3 degree to the south of Saturn. Read more.

Tom Wildoner wrote: “One of my favorite areas to photograph on the moon near the 1st quarter! I captured this view of the sun lighting up the mountain range called Montes Apenninus. The moon was casting a nice shadow on the back side of the mountains. This mountain range is about 370 miles (600 km) long with some of the peaks rising as high as 3.1 miles (5 km).”

Here’s something else to look for on a 1st quarter moon. Aqilla Othman in Port Dickson, Negeri Sembilan, Malaysia, caught this photo. Notice that he caught Lunar X and Lunar V. These are similar features on the moon that fleetingly take an X or V shape when the moon appears in a 1st quarter phase from Earth.

Here’s a closer look at Lunar X and Lunar V. Photo by Izaty Liyana in Port Dickson, Negeri Sembilan, Malaysia. What is Lunar X?

Bottom line: The moon reaches its first quarter phase on Monday, November 4, 2019, at 10:23 UTC. As viewed from the whole Earth, it’ll be high up at sunset on this Monday evening, looking like half a pie.

Check out EarthSky’s guide to the bright planets.

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View at EarthSky Community Photos. | Our friend Dr Ski in the Philippines caught this photo as night came to his part of the world, on November 4, 2019. He wrote: “The moon has reached 1st quarter and is visible on my side of the planet now.”

A first quarter moon rises around noon and sets around midnight. You’ll likely spot it in late afternoon or early evening, high up in the sky. At this moon phase, the moon is showing us precisely half of its lighted half. Or you might say that – at first quarter moon – we’re seeing half the moon’s day side.

We call this moon a quarter and not a half because it is one quarter of the way around in its orbit of Earth, as measured from one new moon to the next. Also, although a first quarter moon appears half-lit to us, the illuminated portion we see of a first quarter moon truly is just a quarter. We’re now seeing half the moon’s day side, that is. Another lighted quarter of the moon shines just as brightly in the direction opposite Earth!

And what about the term half moon? That’s a beloved term, but not an official one.

Read more: 4 keys to understanding moon phases

The lunar calendars are here! Get your 2020 lunar calendars today. They make great gifts. Going fast.

The 1st quarter moon comes on October 5, 2019, at 16:47 Universal Time (UTC). Then, some four hours later, the moon passes 0.3 degree to the south of Saturn. Read more.

Tom Wildoner wrote: “One of my favorite areas to photograph on the moon near the 1st quarter! I captured this view of the sun lighting up the mountain range called Montes Apenninus. The moon was casting a nice shadow on the back side of the mountains. This mountain range is about 370 miles (600 km) long with some of the peaks rising as high as 3.1 miles (5 km).”

Here’s something else to look for on a 1st quarter moon. Aqilla Othman in Port Dickson, Negeri Sembilan, Malaysia, caught this photo. Notice that he caught Lunar X and Lunar V. These are similar features on the moon that fleetingly take an X or V shape when the moon appears in a 1st quarter phase from Earth.

Here’s a closer look at Lunar X and Lunar V. Photo by Izaty Liyana in Port Dickson, Negeri Sembilan, Malaysia. What is Lunar X?

Bottom line: The moon reaches its first quarter phase on Monday, November 4, 2019, at 10:23 UTC. As viewed from the whole Earth, it’ll be high up at sunset on this Monday evening, looking like half a pie.

Check out EarthSky’s guide to the bright planets.

Help EarthSky keep going! Please donate.

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

NASA studies plan to send an orbiter to Pluto

False-color view of Pluto, as seen by New Horizons in 2015. Image via NASA/JHUAPL/SwRI.

New Horizons‘ flyby of Pluto in July 2015 was one of the most exciting events in planetary exploration. We finally got to see this distant world and its moons close-up for the first time in history. Unfortunately, however, it was only a quick flyby. Since then, there has been a lot of talk of a return mission to Pluto. And now, just such a mission may be on the drawing boards. NASA is now exploring the possibility of sending a spacecraft back to Pluto, but this time to stay much longer, with an orbiter. The Southwest Research Institute (SwRI) has announced that it has been awarded funding by NASA to study attributes, feasibility and cost of such a mission.

This would certainly be exciting if the mission is approved. As of right now, it is one of 10 mission studies that NASA is sponsoring, in preparation for the next Planetary Science Decadal Survey. The results of these studies will be delivered to the National Academy Planetary Decadal Study in 2020. According to Carly Howett at SwRI who is leading the study:

We’re excited to have this opportunity to inform the decadal survey deliberations with this study. Our mission concept is to send a single spacecraft to orbit Pluto for two Earth years before breaking away to visit at least one KBO and one other KBO dwarf planet.

EarthSky 2020 lunar calendars are available! They make great gifts. Order now. Going fast!

Pluto and its largest moon Charon, as seen by New Horizons on July 14, 2015. Image via NASA/JHUAPL/SwRI.

The study will develop the spacecraft and payload design requirements, as well as make preliminary cost and risk assessments for new technologies that will be required.

As Alan Stern, principal investigator of the New Horizons mission also noted, an orbiter could orbit Pluto for a period of time, and then take off again to go deeper into the Kuiper Belt:

In an SwRI-funded study that preceded this new NASA-funded study, we developed a Pluto system orbital tour, showing the mission was possible with planned capability launch vehicles and existing electric propulsion systems. We also showed it is possible to use gravity assists from Pluto’s largest moon, Charon, to escape Pluto orbit and to go back into the Kuiper Belt for the exploration of more KBOs like MU69 and at least once more dwarf planet for comparison to Pluto.

Previously, NASA and the planetary science community thought the next step in Kuiper Belt exploration would be to choose between ‘going deep’ in the study of Pluto and its moons or ‘going broad’ by examining smaller Kuiper Belt objects and another dwarf planet for comparison to Pluto. The planetary science community debated which was the right next step. Our studies show you can do both in a single mission: it’s a game changer.

Sputnik Planitia is a vast plain of nitrogen ice on Pluto, surrounded by mountains of water ice. Image via Stern et al./NASA/JHUAPL/SwRI/Science.

Stunning image of Pluto backlit by the sun, with its bluish hazy nitrogen atmosphere, as seen by New Horizons. Image via NASA/JHUAPL/SwRI/Science.

Pluto’s largest moon, Charon, has huge canyons and a reddish north polar cap. Image via NASA/JHUAPL/SwRI.

An orbiter would have some great advantages over the previous flyby mission. As well as having much more time, it could carry more instruments to study Pluto and its moons in detail. An orbiter would be able to help answer many of the questions that New Horizons left behind. According to Tiffany Finley at SwRI:

This tour is far from optimized, yet it is capable of making five or more flybys of each of Pluto’s four small moons, while examining Pluto’s polar and equatorial regions using plane changes. The plan also allows for an extensive up-close encounter with Charon before dipping into Pluto’s atmosphere for sampling before the craft uses Charon one last time to escape into the Kuiper Belt for new assignments.

The Pluto orbiter could use the same xenon ion propulsion system that the Dawn spacecraft used to go to Ceres and Vesta. Stern said:

Who would have thought that a single mission using already available electric propulsion engines could do all this? Now that our team has shown that the planetary science community doesn’t have to choose between a Pluto orbiter or flybys of other bodies in the Kuiper Belt, but can have both, I call this combined mission the ‘gold standard’ for future Pluto and Kuiper Belt exploration.

A Pluto orbiter would, however, need a much better communications system. It took 16 months to transfer all of the data collected back to Earth, and the spacecraft only had 16 GBs of data storage.

Artist’s concept of New Horizons during its flyby of Pluto on July 14, 2015. The new orbiter would be able to stay much longer and have more instruments to study Pluto and its moons in detail. Image via NASA/UFC Today.

Carly Howett at SwRI, who is leading the new study to send an orbiter to Pluto. Image via SwRI.

When New Horizons reached Pluto and its moons, it found exotic worlds full of surprises.

Rather than just a cold, frozen and inert body, Pluto was revealed to be surprisingly geologically active, with vast plains and glaciers of nitrogen ice, possible ice volcanoes, tall mountains of solid water ice capped with methane snow and unusual tall “spikes” of ice that resemble penitentes on Earth. Its very thin atmosphere is hazy with possible small clouds. There is even evidence that Pluto – of all places – may still still have a liquid water ocean deep beneath its outer crust. How cool is that? New Horizons only had a brief look at Pluto, but it was enough to revolutionize our understanding of this little, distant world and its moons.

Pluto’s largest moon, Charon, has large canyons, an odd isolated mountain – another possible ice volcano – sitting all by itself in a depression and a reddish northern polar cap.

New Horizons later went on to visit 2014 MU69, aka Ultima Thule, a much smaller Kuiper Belt Object (KBO) far beyond Pluto. Pluto is the largest known object in the Kuiper Belt, a giant ring of asteroids orbiting the sun out past Neptune, and similar to the main asteroid belt between Mars and Jupiter.

The New Horizons mission was phenomenal even though it was just a brief flyby. Who knows what an actual orbiter around Pluto might find?

Bottom line: After the highly successful New Horizons mission, NASA is now considering sending an orbiter to Pluto, with SwRI being awarded funding to study the exciting proposal.

Via SwRI

from EarthSky https://ift.tt/2pvtf4L

False-color view of Pluto, as seen by New Horizons in 2015. Image via NASA/JHUAPL/SwRI.

New Horizons‘ flyby of Pluto in July 2015 was one of the most exciting events in planetary exploration. We finally got to see this distant world and its moons close-up for the first time in history. Unfortunately, however, it was only a quick flyby. Since then, there has been a lot of talk of a return mission to Pluto. And now, just such a mission may be on the drawing boards. NASA is now exploring the possibility of sending a spacecraft back to Pluto, but this time to stay much longer, with an orbiter. The Southwest Research Institute (SwRI) has announced that it has been awarded funding by NASA to study attributes, feasibility and cost of such a mission.

This would certainly be exciting if the mission is approved. As of right now, it is one of 10 mission studies that NASA is sponsoring, in preparation for the next Planetary Science Decadal Survey. The results of these studies will be delivered to the National Academy Planetary Decadal Study in 2020. According to Carly Howett at SwRI who is leading the study:

We’re excited to have this opportunity to inform the decadal survey deliberations with this study. Our mission concept is to send a single spacecraft to orbit Pluto for two Earth years before breaking away to visit at least one KBO and one other KBO dwarf planet.

EarthSky 2020 lunar calendars are available! They make great gifts. Order now. Going fast!

Pluto and its largest moon Charon, as seen by New Horizons on July 14, 2015. Image via NASA/JHUAPL/SwRI.

The study will develop the spacecraft and payload design requirements, as well as make preliminary cost and risk assessments for new technologies that will be required.

As Alan Stern, principal investigator of the New Horizons mission also noted, an orbiter could orbit Pluto for a period of time, and then take off again to go deeper into the Kuiper Belt:

In an SwRI-funded study that preceded this new NASA-funded study, we developed a Pluto system orbital tour, showing the mission was possible with planned capability launch vehicles and existing electric propulsion systems. We also showed it is possible to use gravity assists from Pluto’s largest moon, Charon, to escape Pluto orbit and to go back into the Kuiper Belt for the exploration of more KBOs like MU69 and at least once more dwarf planet for comparison to Pluto.

Previously, NASA and the planetary science community thought the next step in Kuiper Belt exploration would be to choose between ‘going deep’ in the study of Pluto and its moons or ‘going broad’ by examining smaller Kuiper Belt objects and another dwarf planet for comparison to Pluto. The planetary science community debated which was the right next step. Our studies show you can do both in a single mission: it’s a game changer.

Sputnik Planitia is a vast plain of nitrogen ice on Pluto, surrounded by mountains of water ice. Image via Stern et al./NASA/JHUAPL/SwRI/Science.

Stunning image of Pluto backlit by the sun, with its bluish hazy nitrogen atmosphere, as seen by New Horizons. Image via NASA/JHUAPL/SwRI/Science.

Pluto’s largest moon, Charon, has huge canyons and a reddish north polar cap. Image via NASA/JHUAPL/SwRI.

An orbiter would have some great advantages over the previous flyby mission. As well as having much more time, it could carry more instruments to study Pluto and its moons in detail. An orbiter would be able to help answer many of the questions that New Horizons left behind. According to Tiffany Finley at SwRI:

This tour is far from optimized, yet it is capable of making five or more flybys of each of Pluto’s four small moons, while examining Pluto’s polar and equatorial regions using plane changes. The plan also allows for an extensive up-close encounter with Charon before dipping into Pluto’s atmosphere for sampling before the craft uses Charon one last time to escape into the Kuiper Belt for new assignments.

The Pluto orbiter could use the same xenon ion propulsion system that the Dawn spacecraft used to go to Ceres and Vesta. Stern said:

Who would have thought that a single mission using already available electric propulsion engines could do all this? Now that our team has shown that the planetary science community doesn’t have to choose between a Pluto orbiter or flybys of other bodies in the Kuiper Belt, but can have both, I call this combined mission the ‘gold standard’ for future Pluto and Kuiper Belt exploration.

A Pluto orbiter would, however, need a much better communications system. It took 16 months to transfer all of the data collected back to Earth, and the spacecraft only had 16 GBs of data storage.

Artist’s concept of New Horizons during its flyby of Pluto on July 14, 2015. The new orbiter would be able to stay much longer and have more instruments to study Pluto and its moons in detail. Image via NASA/UFC Today.

Carly Howett at SwRI, who is leading the new study to send an orbiter to Pluto. Image via SwRI.

When New Horizons reached Pluto and its moons, it found exotic worlds full of surprises.

Rather than just a cold, frozen and inert body, Pluto was revealed to be surprisingly geologically active, with vast plains and glaciers of nitrogen ice, possible ice volcanoes, tall mountains of solid water ice capped with methane snow and unusual tall “spikes” of ice that resemble penitentes on Earth. Its very thin atmosphere is hazy with possible small clouds. There is even evidence that Pluto – of all places – may still still have a liquid water ocean deep beneath its outer crust. How cool is that? New Horizons only had a brief look at Pluto, but it was enough to revolutionize our understanding of this little, distant world and its moons.

Pluto’s largest moon, Charon, has large canyons, an odd isolated mountain – another possible ice volcano – sitting all by itself in a depression and a reddish northern polar cap.

New Horizons later went on to visit 2014 MU69, aka Ultima Thule, a much smaller Kuiper Belt Object (KBO) far beyond Pluto. Pluto is the largest known object in the Kuiper Belt, a giant ring of asteroids orbiting the sun out past Neptune, and similar to the main asteroid belt between Mars and Jupiter.

The New Horizons mission was phenomenal even though it was just a brief flyby. Who knows what an actual orbiter around Pluto might find?

Bottom line: After the highly successful New Horizons mission, NASA is now considering sending an orbiter to Pluto, with SwRI being awarded funding to study the exciting proposal.

Via SwRI

from EarthSky https://ift.tt/2pvtf4L

What’s the birthstone for November?

Facet cut topaz gemstones in various colors. Image via Wikipedia.

November’s birthstone is the topaz. The word topaz comes from a Sanskrit word meaning fire. Ancient lore said the topaz could be used to control heat. It was said to have the power to cool boiling water, as well as excessive anger. As medication, topaz was used to cure fever.

Topaz occurs in a range of magnificent colors – blue, pale green, varying shades of yellow, pink, red, brown and even black. Pure topaz itself is a colorless stone. Red and some pink topaz get their colors from chromium that is substituted for aluminum in the crystals. But most other colors occur due to minor element substitutions and defects in the crystal. Some colors are unstable and can fade away; for example, brown topaz mined in Siberia can be bleached by sunlight. In other stones, color changes can be induced by heating. High energy irradiation and moderate heat treatment of colorless topaz can transform it to blue gemstones.

Chemically, topaz is known as aluminum silicate fluoride hydroxide. Because of strong chemical bonds within this mineral, topaz is the hardest of silicate minerals. Topaz gemstones occur in a large variety of sizes, from tiny crystals to large rocks. The biggest uncut stone, a specimen found in Brazil weighing almost 600 pounds, is on display at the American Museum of Natural History in New York. A famous cut topaz in history is found among the crown jewels of Portugal, a magnificent yellow stone weighing 12 ounces.

Photo via Orbital Joe/Flickr

This gem, with its lively fire, clarity, beautiful colors and hardness is ideal for jewelry such as clips, necklaces, brooches and bracelets. Pure topaz, when brilliantly cut, can be often mistaken for a diamond. Because of its rarity, topaz is an expensive gem. The most valued and rarest color is red. Imperial topaz-sherry colored varieties of brownish-yellow, orange-yellow and reddish brown-are the most popular topaz stones and command high prices, as do pink colored stones. Light blue and pale yellow topaz are of less value, but are nevertheless stunning in beauty.

Brazil is the largest producer of topaz, the most notable source being the Minas Geranis region. Gems are also found in Russia, the Ukraine, Pakistan, Scotland, Japan and Sri Lanka. In the United States, the gemstones have been found in Colorado and California.

During the Middle Ages, the topaz was used mostly by royalty and clergy. A 13th century belief held that a topaz engraved with a falcon helped its wearer cultivate the goodwill of kings, princes and magnates.

Topaz was once thought to strengthen the mind, increase wisdom, and prevent mental disorders. It was thought to guard against sudden death. Powdered topaz added to wine was used to prevent asthma and insomnia. A cure for weak vision called for immersing the stone in wine for three days and nights, then rubbing the liquid on the eyes.

Find out about the birthstones for the other months of the year:
January birthstone
February birthstone
March birthstone
April birthstone
May birthstone
June birthstone
July birthstone
August birthstone
September birthstone
October birthstone
November birthstone
December birthstone

Bottom line: The birthstone for November is the topaz.

from EarthSky https://ift.tt/32fvHcN

Facet cut topaz gemstones in various colors. Image via Wikipedia.

November’s birthstone is the topaz. The word topaz comes from a Sanskrit word meaning fire. Ancient lore said the topaz could be used to control heat. It was said to have the power to cool boiling water, as well as excessive anger. As medication, topaz was used to cure fever.

Topaz occurs in a range of magnificent colors – blue, pale green, varying shades of yellow, pink, red, brown and even black. Pure topaz itself is a colorless stone. Red and some pink topaz get their colors from chromium that is substituted for aluminum in the crystals. But most other colors occur due to minor element substitutions and defects in the crystal. Some colors are unstable and can fade away; for example, brown topaz mined in Siberia can be bleached by sunlight. In other stones, color changes can be induced by heating. High energy irradiation and moderate heat treatment of colorless topaz can transform it to blue gemstones.

Chemically, topaz is known as aluminum silicate fluoride hydroxide. Because of strong chemical bonds within this mineral, topaz is the hardest of silicate minerals. Topaz gemstones occur in a large variety of sizes, from tiny crystals to large rocks. The biggest uncut stone, a specimen found in Brazil weighing almost 600 pounds, is on display at the American Museum of Natural History in New York. A famous cut topaz in history is found among the crown jewels of Portugal, a magnificent yellow stone weighing 12 ounces.

Photo via Orbital Joe/Flickr

This gem, with its lively fire, clarity, beautiful colors and hardness is ideal for jewelry such as clips, necklaces, brooches and bracelets. Pure topaz, when brilliantly cut, can be often mistaken for a diamond. Because of its rarity, topaz is an expensive gem. The most valued and rarest color is red. Imperial topaz-sherry colored varieties of brownish-yellow, orange-yellow and reddish brown-are the most popular topaz stones and command high prices, as do pink colored stones. Light blue and pale yellow topaz are of less value, but are nevertheless stunning in beauty.

Brazil is the largest producer of topaz, the most notable source being the Minas Geranis region. Gems are also found in Russia, the Ukraine, Pakistan, Scotland, Japan and Sri Lanka. In the United States, the gemstones have been found in Colorado and California.

During the Middle Ages, the topaz was used mostly by royalty and clergy. A 13th century belief held that a topaz engraved with a falcon helped its wearer cultivate the goodwill of kings, princes and magnates.

Topaz was once thought to strengthen the mind, increase wisdom, and prevent mental disorders. It was thought to guard against sudden death. Powdered topaz added to wine was used to prevent asthma and insomnia. A cure for weak vision called for immersing the stone in wine for three days and nights, then rubbing the liquid on the eyes.

Find out about the birthstones for the other months of the year:
January birthstone
February birthstone
March birthstone
April birthstone
May birthstone
June birthstone
July birthstone
August birthstone
September birthstone
October birthstone
November birthstone
December birthstone

Bottom line: The birthstone for November is the topaz.

from EarthSky https://ift.tt/32fvHcN

Revolutionising radiotherapy: making a cornerstone cancer treatment more personal and powerful

“We have a very powerful treatment which contributes to the cure of cancer in around a third of patients treated,” says Professor David Sebag-Montefiore from the University of Leeds of radiotherapy, a cornerstone of cancer treatment in the UK.

But there’s always room for improvement. “Some of the radiotherapy we give today isn’t doing a good enough job.”

We want more people to reap the benefits of this tried and tested treatment, so we’re investing £56 million to launch the CRUK Radiation Research Network (CRUK RadNet). This will support radiotherapy research in seven specialist institutes across the UK and aims to propel radiotherapy into the future.

It’s money to develop new tech, harness the power of existing ones, apply approaches like artificial intelligence (AI) and to help scientists really understand what’s going on when cancer cells are hit by radiotherapy beams, so we can use drugs to boost their cancer-killing effects.

“Because radiotherapy is an effective treatment across such a broad range of cancers it’s clearly a job that can’t be achieved in one centre alone,” says Sebag-Montefiore. This new initiative hopes to make use of the different expertise from each research station involved, bringing in knowledge from scientists who have never worked in radiotherapy before. “This network will allow us to focus along the breath of cancer research and actually make a big impact.”

Although radiotherapy has become extremely advanced in the last couple of decades and comes in many high-tech forms, there are still plenty of questions around how it’s effects can be maximised to benefit more people and how to reduce side effects of the treatment.

Here are just three of a number of research areas CRUK RadNet hopes to get answers for.

How does radiotherapy affect the tumour microenvironment?

Radiotherapy works by damaging the DNA of cancer cells. “These fatal DNA breaks mean the cancer cells can’t divide,” says Sebag-Montefiore.

But cancer cells aren’t just quietly hanging out by themselves. They’re sitting in a busy environment of blood cells, immune cells and healthy tissues, all of whom are likely to be interacting.

The full extent of the influence these cells have on each other is still unclear, but clues from the clinic suggest that the immune system plays an important role in mopping up cancer cells after radiotherapy, even after they’ve spread to other parts of the body.

“Clinically we are now starting to see situations in people who have incurable cancer that has spread, where irradiating the primary tumour improves their survival,” says Sebag-Montefiore. It’s a positive benefit that scientists are still working to understand.

Professor David Sebag-Montefiore, University of Leeds

One theory is that radiation causes cancer cells to break down and release their contents, which creates lots of interesting molecules for the immune system to detect and home in on. The energised immune cells then move around the body looking for cancer cells displaying these same molecules. And when they find them, they kill them, which may explain why tumours that are distant from where the cancer first started shrink.

Figuring out what’s going on in and around a tumour when it’s being irradiated could point to ways to enhance treatment and may even help radiotherapy work for those who currently don’t respond to it. For example, immunotherapies could give immune cells the boost they need to turn against tumours. Or, giving patients drugs that stop cancer cells repairing their DNA alongside radiotherapy might give the cancer an extra blow.

Sebag-Montefiore  says there is clearly a substantial piece of work needed to understand the environment that the radiotherapy beams operate in and are also creating. Learning more about this will help us “know how to best to harness the microenvironment and have maximum impact”.

“This is a significant part of the work that will be done in CRUK RadNet.”

How could AI improve radiotherapy?

Every day we hear of new ways that AI is improving everything from how we shop to healthcare. Now Sebag-Montefiore and his team in Leeds, alongside researchers across the CRUK RadNet network, are exploring how it can be used to help cancer treatment.

“In Leeds, we think we can harness AI to actually improve how radiotherapy is given to patients.”

Computer programmes may help them deliver a highly targeted radiotherapy called SABR more accurately, sparing healthy cells. “Both the tumour and the organ we target during treatment move so we apply a safety margin around the tumour to make sure we hit the whole tumour. At the moment this margin is pretty much the same for every patient.”

But the money from CRUK RadNet will allow them to develop algorithms that could work out the exact area the radiotherapy beam will need to cover for each patient. The team hope to use AI to analyse MRI scans from a range of cancers that are in areas of the body that move a lot, like the liver.

“We could analyse those scans with AI to build up a personalised picture of the actual movement,” which means more precise treatment and fewer side effects.

Why do cancer cells become resistant to radiotherapy?

Unfortunately, radiotherapy doesn’t work on everyone.

“We need to understand why radiotherapy isn’t as effective as it could be in some patients,” says Sebag-Montefiore.

“Within all cancers we can identify some groups of patients where radiotherapy resistance is a major barrier to the cure of cancer.”

This may be someone whose cancer initially responds well to treatment but then it stops working. Or, in a few cases, radiotherapy might have no affect at all.

CRUK RadNet members are investigating resistance from a number of angles, looking at ways to overcome the fact that radiotherapy can’t destroy certain cancers. They’re particularly focusing on the cancer types where survival is still depressingly low, like pancreatic cancer and brain tumours.

For instance, a team in Manchester are delving into how radiotherapy changes the biology of cancer cells and how this may contribute to them standing firm against its powerful beams.

A community effort

Sebag-Montefiore is keen to get going. “The last 10 years have seen significant progress in radiotherapy research, but we can do better.”

He says the network now needs to make sure they work with the whole UK radiotherapy community to make sure they do the best science. Because for Sebag-Montefiore, the potential impact of the network is huge.

“CRUK RadNet is a fantastic investment because it gives us a great chance in improving radiotherapy cure rates and reduce side effects further to ensure patients are getting the best possible treatment.”

Gabi

from Cancer Research UK – Science blog https://ift.tt/33fuwLR

“We have a very powerful treatment which contributes to the cure of cancer in around a third of patients treated,” says Professor David Sebag-Montefiore from the University of Leeds of radiotherapy, a cornerstone of cancer treatment in the UK.

But there’s always room for improvement. “Some of the radiotherapy we give today isn’t doing a good enough job.”

We want more people to reap the benefits of this tried and tested treatment, so we’re investing £56 million to launch the CRUK Radiation Research Network (CRUK RadNet). This will support radiotherapy research in seven specialist institutes across the UK and aims to propel radiotherapy into the future.

It’s money to develop new tech, harness the power of existing ones, apply approaches like artificial intelligence (AI) and to help scientists really understand what’s going on when cancer cells are hit by radiotherapy beams, so we can use drugs to boost their cancer-killing effects.

“Because radiotherapy is an effective treatment across such a broad range of cancers it’s clearly a job that can’t be achieved in one centre alone,” says Sebag-Montefiore. This new initiative hopes to make use of the different expertise from each research station involved, bringing in knowledge from scientists who have never worked in radiotherapy before. “This network will allow us to focus along the breath of cancer research and actually make a big impact.”

Although radiotherapy has become extremely advanced in the last couple of decades and comes in many high-tech forms, there are still plenty of questions around how it’s effects can be maximised to benefit more people and how to reduce side effects of the treatment.

Here are just three of a number of research areas CRUK RadNet hopes to get answers for.

How does radiotherapy affect the tumour microenvironment?

Radiotherapy works by damaging the DNA of cancer cells. “These fatal DNA breaks mean the cancer cells can’t divide,” says Sebag-Montefiore.

But cancer cells aren’t just quietly hanging out by themselves. They’re sitting in a busy environment of blood cells, immune cells and healthy tissues, all of whom are likely to be interacting.

The full extent of the influence these cells have on each other is still unclear, but clues from the clinic suggest that the immune system plays an important role in mopping up cancer cells after radiotherapy, even after they’ve spread to other parts of the body.

“Clinically we are now starting to see situations in people who have incurable cancer that has spread, where irradiating the primary tumour improves their survival,” says Sebag-Montefiore. It’s a positive benefit that scientists are still working to understand.

Professor David Sebag-Montefiore, University of Leeds

One theory is that radiation causes cancer cells to break down and release their contents, which creates lots of interesting molecules for the immune system to detect and home in on. The energised immune cells then move around the body looking for cancer cells displaying these same molecules. And when they find them, they kill them, which may explain why tumours that are distant from where the cancer first started shrink.

Figuring out what’s going on in and around a tumour when it’s being irradiated could point to ways to enhance treatment and may even help radiotherapy work for those who currently don’t respond to it. For example, immunotherapies could give immune cells the boost they need to turn against tumours. Or, giving patients drugs that stop cancer cells repairing their DNA alongside radiotherapy might give the cancer an extra blow.

Sebag-Montefiore  says there is clearly a substantial piece of work needed to understand the environment that the radiotherapy beams operate in and are also creating. Learning more about this will help us “know how to best to harness the microenvironment and have maximum impact”.

“This is a significant part of the work that will be done in CRUK RadNet.”

How could AI improve radiotherapy?

Every day we hear of new ways that AI is improving everything from how we shop to healthcare. Now Sebag-Montefiore and his team in Leeds, alongside researchers across the CRUK RadNet network, are exploring how it can be used to help cancer treatment.

“In Leeds, we think we can harness AI to actually improve how radiotherapy is given to patients.”

Computer programmes may help them deliver a highly targeted radiotherapy called SABR more accurately, sparing healthy cells. “Both the tumour and the organ we target during treatment move so we apply a safety margin around the tumour to make sure we hit the whole tumour. At the moment this margin is pretty much the same for every patient.”

But the money from CRUK RadNet will allow them to develop algorithms that could work out the exact area the radiotherapy beam will need to cover for each patient. The team hope to use AI to analyse MRI scans from a range of cancers that are in areas of the body that move a lot, like the liver.

“We could analyse those scans with AI to build up a personalised picture of the actual movement,” which means more precise treatment and fewer side effects.

Why do cancer cells become resistant to radiotherapy?

Unfortunately, radiotherapy doesn’t work on everyone.

“We need to understand why radiotherapy isn’t as effective as it could be in some patients,” says Sebag-Montefiore.

“Within all cancers we can identify some groups of patients where radiotherapy resistance is a major barrier to the cure of cancer.”

This may be someone whose cancer initially responds well to treatment but then it stops working. Or, in a few cases, radiotherapy might have no affect at all.

CRUK RadNet members are investigating resistance from a number of angles, looking at ways to overcome the fact that radiotherapy can’t destroy certain cancers. They’re particularly focusing on the cancer types where survival is still depressingly low, like pancreatic cancer and brain tumours.

For instance, a team in Manchester are delving into how radiotherapy changes the biology of cancer cells and how this may contribute to them standing firm against its powerful beams.

A community effort

Sebag-Montefiore is keen to get going. “The last 10 years have seen significant progress in radiotherapy research, but we can do better.”

He says the network now needs to make sure they work with the whole UK radiotherapy community to make sure they do the best science. Because for Sebag-Montefiore, the potential impact of the network is huge.

“CRUK RadNet is a fantastic investment because it gives us a great chance in improving radiotherapy cure rates and reduce side effects further to ensure patients are getting the best possible treatment.”

Gabi

from Cancer Research UK – Science blog https://ift.tt/33fuwLR