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Deneb and Cygnus the Swan

Tonight’s chart has you looking eastward at the famous Summer Triangle. Today, notice the star Deneb, the northernmost star in the Summer Triangle. Its constellation is Cygnus the Swan. In a dark country sky, you can see that Cygnus is flying along the starlit trail of the summer Milky Way.

The photo below is from Annie Lewis in Spain. She solved the problem of picking out the Summer Triangle from among many stars in the night sky by looking for the Triangle in the east soon after sunset. These three stars are, after all, among the brightest in the sky.

EarthSky’s meteor shower guide for 2020

EarthSky astronomy kits are perfect for beginners. Order yours today.

Medium blue sky with a few scattered stars, three bright ones labeled.

EarthSky Facebook friend Annie Lewis in Madrid, Spain, captured this photo of the Summer Triangle shortly after nightfall on a summer night. In fact, she said, the only stars visible to the unaided eye when she took the photo were the three in the Triangle. But her camera knew better. Thanks, Annie.

If it’s darker out, you might recognize the Summer Triangle by noticing that there is a cross within the Triangle. The constellation Cygnus is that cross. In fact, the constellation Cygnus is sometimes called the Northern Cross.

Okay, I’ve given you a lot of names here: Summer Triangle, Cygnus, Northern Cross.

Just remember, the constellation Cygnus the Swan contains the Northern Cross. The Cross is – more or less – just another way to see the Swan. The Northern Cross is what’s called an asterism, or recognizable pattern within a constellation. In this case, the pattern is the whole constellation, pretty much. At least, I never see them any differently.

Except for one thing. Deneb is at the top of the Cross, but at the tail of the Swan (the star name “deneb” always means “tail”). The little star Albireo is at the head of the Swan, but at the base of the Cross. Whew!

Our Summer Triangle series also includes:

Part 1: Vega and its constellation Lyra

Part 3: Altair and its constellation Aquila

Bottom line: The Summer Triangle consists of three bright stars – Vega, Deneb and Altair – in three different constellations. Deneb also represents the tail of Cygnus the Swan.

Help support posts like these at the EarthSky store. Fun astronomy gifts and tools for all ages!



from EarthSky https://ift.tt/2Lym1pZ

Tonight’s chart has you looking eastward at the famous Summer Triangle. Today, notice the star Deneb, the northernmost star in the Summer Triangle. Its constellation is Cygnus the Swan. In a dark country sky, you can see that Cygnus is flying along the starlit trail of the summer Milky Way.

The photo below is from Annie Lewis in Spain. She solved the problem of picking out the Summer Triangle from among many stars in the night sky by looking for the Triangle in the east soon after sunset. These three stars are, after all, among the brightest in the sky.

EarthSky’s meteor shower guide for 2020

EarthSky astronomy kits are perfect for beginners. Order yours today.

Medium blue sky with a few scattered stars, three bright ones labeled.

EarthSky Facebook friend Annie Lewis in Madrid, Spain, captured this photo of the Summer Triangle shortly after nightfall on a summer night. In fact, she said, the only stars visible to the unaided eye when she took the photo were the three in the Triangle. But her camera knew better. Thanks, Annie.

If it’s darker out, you might recognize the Summer Triangle by noticing that there is a cross within the Triangle. The constellation Cygnus is that cross. In fact, the constellation Cygnus is sometimes called the Northern Cross.

Okay, I’ve given you a lot of names here: Summer Triangle, Cygnus, Northern Cross.

Just remember, the constellation Cygnus the Swan contains the Northern Cross. The Cross is – more or less – just another way to see the Swan. The Northern Cross is what’s called an asterism, or recognizable pattern within a constellation. In this case, the pattern is the whole constellation, pretty much. At least, I never see them any differently.

Except for one thing. Deneb is at the top of the Cross, but at the tail of the Swan (the star name “deneb” always means “tail”). The little star Albireo is at the head of the Swan, but at the base of the Cross. Whew!

Our Summer Triangle series also includes:

Part 1: Vega and its constellation Lyra

Part 3: Altair and its constellation Aquila

Bottom line: The Summer Triangle consists of three bright stars – Vega, Deneb and Altair – in three different constellations. Deneb also represents the tail of Cygnus the Swan.

Help support posts like these at the EarthSky store. Fun astronomy gifts and tools for all ages!



from EarthSky https://ift.tt/2Lym1pZ

News digest – light-activated nanoparticles, Government’s obesity plans, tumour ‘glue’ and AI research fund

With news about the coronavirus pandemic developing daily, we want to make sure everyone affected by cancer gets the information they need during this time. 

We’re pulling together the latest government and NHS health updates from across the UK in a separate blog post, which we’re updating regularly. 

New rare blood cancer treatment gets green light for NHS in England 

A new combined therapy with the drug brentuximab has been approved for adults with a rare type of fast-growing lymphoma. Clinical trial evidence suggests the treatment could give people with this type of blood cancer more time before their disease progresses. More on this in our news report 

Government announces new push to tackle obesity 

Boris Johnson is set to announce restrictions on multi-buy and similar price promotions on a range of foods high in fat, sugar or salt in a bid to tackle rising obesity in the UK, according to The Times (£) and Guardian. The announcement comes off the back of evidence showing that 40% of food spending goes on products on promotion. However, health campaigners have expressed their disappointment at the seeming lack of action on junk food marketing. According to the leaked documents, a 9pm watershed on junk food adverts is ‘not on the cards at this time’, although the plans may change in the coming weeks.

Light-activated nanoparticles target cancer 

Scientists have developed light-activated nanoparticles that kill skin cancer cells in mice. The treatment involves linking tiny particles to short pieces of RNA that inhibit the production of essential proteins that cancer cells need to survive. It’s early days yet, but scientists are hopeful that the light-activated technology can help to reduce side effects and make the treatment more targeted. Read more on this at New Atlas.   

Scientists discover how cellular ‘glue’ can disrupt division  

An excess of a protein that’s essential to cell division – PRC1 – has been linked to many types of cancer, including prostate, ovarian and breast. Now scientists have found that the protein acts as a glue during cell division, precisely controlling the speed at which DNA strands separate as a single cell divides. These findings could help to explain why too much or too little PRC1 disrupts the division process and can be linked to cancer developing. Full story at Technology Networks.

AI investment to help improve lung cancer diagnosis 

Earlier this month, the Government announced over £16 million pounds in research funding to help improve the diagnosis of cancer and other life-threatening diseases, with Cancer Research UK putting in £3 million. Some of that money will go towards an Oxford-led project to improve lung cancer diagnosis. The team hope to use artificial intelligence to combine clinical, imaging and molecular data and make lung cancer diagnosis more accurate. More on this at Digital Health 

Partnership to develop new custom antibodies for cancer research 

We’ve partnered with Abcam to develop custom antibodies that could facilitate cancer research. Dr John Baker at Abcam said: “We are proud to be working with Cancer Research UK to support their scientists and help them achieve their next breakthrough faster.” Find out more at Cambridge Independent

And finally…. 

Technology Networks reports on a new study that has taken a closer look at how tiny bubble-like structures called vesicles can help cancer cells spread. Scientists found that vesicles from cancer cells contained high levels of proteins with lipid molecules attached, which are associated with the spread of cancer. We’ve blogged before about how tumours spread.

Scarlett Sangster is a writer for PA Media Group



from Cancer Research UK – Science blog https://ift.tt/3033GWI

With news about the coronavirus pandemic developing daily, we want to make sure everyone affected by cancer gets the information they need during this time. 

We’re pulling together the latest government and NHS health updates from across the UK in a separate blog post, which we’re updating regularly. 

New rare blood cancer treatment gets green light for NHS in England 

A new combined therapy with the drug brentuximab has been approved for adults with a rare type of fast-growing lymphoma. Clinical trial evidence suggests the treatment could give people with this type of blood cancer more time before their disease progresses. More on this in our news report 

Government announces new push to tackle obesity 

Boris Johnson is set to announce restrictions on multi-buy and similar price promotions on a range of foods high in fat, sugar or salt in a bid to tackle rising obesity in the UK, according to The Times (£) and Guardian. The announcement comes off the back of evidence showing that 40% of food spending goes on products on promotion. However, health campaigners have expressed their disappointment at the seeming lack of action on junk food marketing. According to the leaked documents, a 9pm watershed on junk food adverts is ‘not on the cards at this time’, although the plans may change in the coming weeks.

Light-activated nanoparticles target cancer 

Scientists have developed light-activated nanoparticles that kill skin cancer cells in mice. The treatment involves linking tiny particles to short pieces of RNA that inhibit the production of essential proteins that cancer cells need to survive. It’s early days yet, but scientists are hopeful that the light-activated technology can help to reduce side effects and make the treatment more targeted. Read more on this at New Atlas.   

Scientists discover how cellular ‘glue’ can disrupt division  

An excess of a protein that’s essential to cell division – PRC1 – has been linked to many types of cancer, including prostate, ovarian and breast. Now scientists have found that the protein acts as a glue during cell division, precisely controlling the speed at which DNA strands separate as a single cell divides. These findings could help to explain why too much or too little PRC1 disrupts the division process and can be linked to cancer developing. Full story at Technology Networks.

AI investment to help improve lung cancer diagnosis 

Earlier this month, the Government announced over £16 million pounds in research funding to help improve the diagnosis of cancer and other life-threatening diseases, with Cancer Research UK putting in £3 million. Some of that money will go towards an Oxford-led project to improve lung cancer diagnosis. The team hope to use artificial intelligence to combine clinical, imaging and molecular data and make lung cancer diagnosis more accurate. More on this at Digital Health 

Partnership to develop new custom antibodies for cancer research 

We’ve partnered with Abcam to develop custom antibodies that could facilitate cancer research. Dr John Baker at Abcam said: “We are proud to be working with Cancer Research UK to support their scientists and help them achieve their next breakthrough faster.” Find out more at Cambridge Independent

And finally…. 

Technology Networks reports on a new study that has taken a closer look at how tiny bubble-like structures called vesicles can help cancer cells spread. Scientists found that vesicles from cancer cells contained high levels of proteins with lipid molecules attached, which are associated with the spread of cancer. We’ve blogged before about how tumours spread.

Scarlett Sangster is a writer for PA Media Group



from Cancer Research UK – Science blog https://ift.tt/3033GWI

Georgia Coast Atlas: A portal to hidden stories

The rich biodiversity of the Georgia coast includes the roseate spoonbill, shown in a marsh on Sapelo Island. Photo by Anthony Martin.

The Georgia Coast Atlas is a public, online gateway to the dynamic ecosystems and intriguing history of the state’s 100-mile-long coast and barrier islands. Emory University’s Department of Environmental Sciences and the Emory Center for Digital Scholarship launched the ambitious project. It showcases scholarship in science and the humanities, weaving together research, fieldwork and technology to create an unprecedented resource for educators, conservationists, students and the general public.

The interactive trove — made up of stunning flyover video, oral and written stories and annotated maps — keeps expanding through the efforts of Emory students and faculty.

“The main aim of the Atlas is to show how special the Georgia coast is as a place,” says Anthony Martin, a professor of practice in Environmental Sciences. “Secondly, it documents how the region is rapidly changing.”

Read the whole story here.

Related:
Ecology of Georgia's St. Catherines Island
Fossil tracks mark student's passage into New World of discovery

from eScienceCommons https://ift.tt/3iS7liI
The rich biodiversity of the Georgia coast includes the roseate spoonbill, shown in a marsh on Sapelo Island. Photo by Anthony Martin.

The Georgia Coast Atlas is a public, online gateway to the dynamic ecosystems and intriguing history of the state’s 100-mile-long coast and barrier islands. Emory University’s Department of Environmental Sciences and the Emory Center for Digital Scholarship launched the ambitious project. It showcases scholarship in science and the humanities, weaving together research, fieldwork and technology to create an unprecedented resource for educators, conservationists, students and the general public.

The interactive trove — made up of stunning flyover video, oral and written stories and annotated maps — keeps expanding through the efforts of Emory students and faculty.

“The main aim of the Atlas is to show how special the Georgia coast is as a place,” says Anthony Martin, a professor of practice in Environmental Sciences. “Secondly, it documents how the region is rapidly changing.”

Read the whole story here.

Related:
Ecology of Georgia's St. Catherines Island
Fossil tracks mark student's passage into New World of discovery

from eScienceCommons https://ift.tt/3iS7liI

Year’s farthest quarter moon July 12

Half-lit Earth from north, and half-lit moon with divisions between dark and light sides lined up.

Click here to see animation. As seen from the north side of the moon’s orbital plane, the Earth rotates counterclockwise on its rotational axis, and the moon revolves counterclockwise around Earth. The terminators of the Earth and moon align at first and last quarter moons.

The most distant quarter moon of the year falls on July 12, 2020. That’s because this quarter moon more closely aligns with lunar apogee – the moon’s farthest point from Earth in its monthly orbit – than does any other quarter moon in 2020.

Moon at apogee: July 12, 2020, at 19:27 UTC (Universal Time)

Last quarter moon: July 12, 2020, at at 23:29 UTC

Four columns of dates and times.

In the year 2020, there are 13 first quarter moons and 12 last quarter moons. Of these 25 quarter moons, the last quarter moon on July 12, 2020, counts as the farthest of them all. Moon phases via AstroPixels.

Although the year’s most distant quarter moon falls on July 12, the lunar apogee accompanying this quarter moon counts as the year’s closest lunar apogee. Of this year’s 14 lunar apogees, the one on July 12, 2020, is the closest of them all. See the table below via AstroPixels.

Two columns of dates, times and distances.

M = year’s farthest perigees and apogees, and m = year’s closest perigees and apogees. Distances given in kilometers. Table via AstroPixels.

It’s no coincidence that the year’s closest lunar apogee happens in close conjunction with the quarter moon. A lunar apogee that closely aligns with a quarter moon is closer than the mean apogee distance of 251,969 miles or 405,504 km. On the other hand, a lunar apogee that closely aligns with the new moon or full moon is farther than the mean apogee distance of 251,969 miles or 405,504 km.

Neil Degrasse Tyson, in an interview, once claimed, “The distance to the moon – okay, the moon orbits us. It’s sometimes closer and it’s sometimes farther away. It has nothing to do with the phase.”

On the contrary, a quarter moon at apogee doesn’t swing as far from Earth as a new or full moon at apogee; conversely, a quarter moon at perigee doesn’t sweep as close to Earth as a new or full moon at perigee. In other words, a quarter moon can never get as close to Earth as a supermoon (new or full moon near perigee) or as far away as a micro-moon (new or full moon near apogee).

Two full moons side by side, one perceptibly larger than the other.

View larger. | The photo contrasts the micro-moon of April 2007 at the right to the supermoon (perigee full moon) of October 2007 on the left. Image via Wikimedia.

For those brave souls wanting to know why quarter moons at apogee/perigee don’t go out as far – or come in as close – as new and full moons at apogee or perigee, we provide an explanation below.

Diagram with lunar orbit in three positions of moon and Earth during the year.

The line connecting lunar perigee with lunar apogee defines the moon’s major axis. At (A) the major axis is pointing directly at the sun, maximizing the eccentricity of the moon’s orbit. At this elongated eccentricity, perigee is maximally close and apogee maximally distant, giving rise to a perigee new moon (supermoon) and an apogee full moon (micro-moon). Then, 3 1/2 lunar months (103 days) later, at (B), the moon’s major axis makes a right angle to the sun-Earth line. This minimizes the eccentricity, lessening the apogee distance yet increasing the perigee distance; and that’s why the quarter moons at perigee/apogee never get as close or as far from Earth as perigean/apogean new or full moons. Seven lunar months (206 days) after the major axis points directly at the sun at (A), it points toward the sun at (C) – except that it’s an apogee new moon (micro-moon) and perigee full moon (supermoon). Generally, the closest perigee comes at full moon and the farthest apogee at new moon. Diagram via Bedford Astronomy Club.

Want to know when the closest lunar apogee will happen in 2021? There’s a lunar cycle whereby 14 lunar months (14 returns to last quarter moon) almost exactly equal 15 returns to apogee. A lunar month refers to the time period between successive returns to the same phase, a mean period of 29.53059 days. An anomalistic month refers to successive returns to apogee (or successive returns to perigee), a mean period of 27.55455 days. Hence:

14 lunar months (14 returns to last quarter moon) x 29.53059 days = 413.428 days
15 anomalistic months (15 returns to lunar apogee) x 27.55455 days = 413.318 days

Therefore, the last quarter moon and lunar apogee will realign in a period of about 413 days (approximately one year, one month and 18 days). Next year, in 2021, the last quarter moon and lunar apogee will realign on August 30, 2021, to present 2021’s closest lunar apogee:

Lunar perigee: August 30, 2021, at 2:22 Universal Time

Last quarter: August 30, 2021, at 7:13 Universal Time

Four columns of dates and times.

Moon phases in 2021 via AstroPixels.

Two columns of dates, times and distances.

Lunar apogees and lunar perigees in the year 2021 via AstroPixels.

Bottom line: On July 12, 2020, we have the year’s most distant quarter moon, yet the year’s closest apogee. Then exactly 14 lunar months (14 returns to last quarter moon) later, 2021’s most distant quarter moon and closest apogee will recur on August 30, 2021.



from EarthSky https://ift.tt/3gPtYCN
Half-lit Earth from north, and half-lit moon with divisions between dark and light sides lined up.

Click here to see animation. As seen from the north side of the moon’s orbital plane, the Earth rotates counterclockwise on its rotational axis, and the moon revolves counterclockwise around Earth. The terminators of the Earth and moon align at first and last quarter moons.

The most distant quarter moon of the year falls on July 12, 2020. That’s because this quarter moon more closely aligns with lunar apogee – the moon’s farthest point from Earth in its monthly orbit – than does any other quarter moon in 2020.

Moon at apogee: July 12, 2020, at 19:27 UTC (Universal Time)

Last quarter moon: July 12, 2020, at at 23:29 UTC

Four columns of dates and times.

In the year 2020, there are 13 first quarter moons and 12 last quarter moons. Of these 25 quarter moons, the last quarter moon on July 12, 2020, counts as the farthest of them all. Moon phases via AstroPixels.

Although the year’s most distant quarter moon falls on July 12, the lunar apogee accompanying this quarter moon counts as the year’s closest lunar apogee. Of this year’s 14 lunar apogees, the one on July 12, 2020, is the closest of them all. See the table below via AstroPixels.

Two columns of dates, times and distances.

M = year’s farthest perigees and apogees, and m = year’s closest perigees and apogees. Distances given in kilometers. Table via AstroPixels.

It’s no coincidence that the year’s closest lunar apogee happens in close conjunction with the quarter moon. A lunar apogee that closely aligns with a quarter moon is closer than the mean apogee distance of 251,969 miles or 405,504 km. On the other hand, a lunar apogee that closely aligns with the new moon or full moon is farther than the mean apogee distance of 251,969 miles or 405,504 km.

Neil Degrasse Tyson, in an interview, once claimed, “The distance to the moon – okay, the moon orbits us. It’s sometimes closer and it’s sometimes farther away. It has nothing to do with the phase.”

On the contrary, a quarter moon at apogee doesn’t swing as far from Earth as a new or full moon at apogee; conversely, a quarter moon at perigee doesn’t sweep as close to Earth as a new or full moon at perigee. In other words, a quarter moon can never get as close to Earth as a supermoon (new or full moon near perigee) or as far away as a micro-moon (new or full moon near apogee).

Two full moons side by side, one perceptibly larger than the other.

View larger. | The photo contrasts the micro-moon of April 2007 at the right to the supermoon (perigee full moon) of October 2007 on the left. Image via Wikimedia.

For those brave souls wanting to know why quarter moons at apogee/perigee don’t go out as far – or come in as close – as new and full moons at apogee or perigee, we provide an explanation below.

Diagram with lunar orbit in three positions of moon and Earth during the year.

The line connecting lunar perigee with lunar apogee defines the moon’s major axis. At (A) the major axis is pointing directly at the sun, maximizing the eccentricity of the moon’s orbit. At this elongated eccentricity, perigee is maximally close and apogee maximally distant, giving rise to a perigee new moon (supermoon) and an apogee full moon (micro-moon). Then, 3 1/2 lunar months (103 days) later, at (B), the moon’s major axis makes a right angle to the sun-Earth line. This minimizes the eccentricity, lessening the apogee distance yet increasing the perigee distance; and that’s why the quarter moons at perigee/apogee never get as close or as far from Earth as perigean/apogean new or full moons. Seven lunar months (206 days) after the major axis points directly at the sun at (A), it points toward the sun at (C) – except that it’s an apogee new moon (micro-moon) and perigee full moon (supermoon). Generally, the closest perigee comes at full moon and the farthest apogee at new moon. Diagram via Bedford Astronomy Club.

Want to know when the closest lunar apogee will happen in 2021? There’s a lunar cycle whereby 14 lunar months (14 returns to last quarter moon) almost exactly equal 15 returns to apogee. A lunar month refers to the time period between successive returns to the same phase, a mean period of 29.53059 days. An anomalistic month refers to successive returns to apogee (or successive returns to perigee), a mean period of 27.55455 days. Hence:

14 lunar months (14 returns to last quarter moon) x 29.53059 days = 413.428 days
15 anomalistic months (15 returns to lunar apogee) x 27.55455 days = 413.318 days

Therefore, the last quarter moon and lunar apogee will realign in a period of about 413 days (approximately one year, one month and 18 days). Next year, in 2021, the last quarter moon and lunar apogee will realign on August 30, 2021, to present 2021’s closest lunar apogee:

Lunar perigee: August 30, 2021, at 2:22 Universal Time

Last quarter: August 30, 2021, at 7:13 Universal Time

Four columns of dates and times.

Moon phases in 2021 via AstroPixels.

Two columns of dates, times and distances.

Lunar apogees and lunar perigees in the year 2021 via AstroPixels.

Bottom line: On July 12, 2020, we have the year’s most distant quarter moon, yet the year’s closest apogee. Then exactly 14 lunar months (14 returns to last quarter moon) later, 2021’s most distant quarter moon and closest apogee will recur on August 30, 2021.



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

Last quarter moon is July 12

One half the moon's face in sunlight, lighted portion facing downward, left side marked N for north.

View at EarthSky Community Photos. | Dr Ski in Valencia, Philippines, caught the last quarter moon shortly after it rose around midnight on the morning of September 22, 2019. This moon phase is perfect for helping you envision the location of the sun … below your feet. Thanks, Dr Ski!

July’s last quarter moon is the most distant quarter moon of 2020. That’s because the instant of last quarter occurs only 4 hours after lunar apogee this month.

Read more: Year’s farthest quarter moon July 12

A last quarter moon appears half-lit by sunshine and half-immersed in its own shadow. It rises in the middle of the night, appears at its highest in the sky around dawn, and sets around midday.

A last quarter moon provides a great opportunity to think of yourself on a three-dimensional world in space. Watch for this moon just after moonrise, shortly after midnight. Then the lighted portion points downward, to the sun below your feet. Think of the last quarter moon as a mirror to the world you’re standing on. Think of yourself standing in the midst of Earth’s nightside, on the midnight portion of Earth.

On a last quarter moon, the lunar terminator – the shadow line dividing day and night – shows you where it’s sunset on the moon.

Craters and other features, including a short straight white line on a dark flat mare floor.

View at EarthSky Community Photos. | September 22, 2019, photo by Dr Ski. He wrote: “The moon’s southern limb at last quarter. The Straight Wall is either black or white depending on the angle of the sun’s rays. At lunar sunset (now), it’s white. Around full moon, Tycho is one of the easiest craters to find due to the impact rays emanating from it. It’s like the hub of a spoked wheel! At last quarter, Tycho becomes unremarkable. Clavius, on the other hand, becomes remarkable at high magnification.”

Labeled craters and mountain ranges at the edge between dark and light.

View at EarthSky Community Photos. | September 22, 2019, photo by Dr Ski. He wrote: “The Sea of Rains at last quarter. The lunar Alps and Apennines are bisected by the moon’s meridian. You can get an idea of the height of these mountains by how far they extend into the dark side of the terminator. At an elevation of over 5,000 meters [16,000 feet], the Apennines are twice as tall as the Alps.”

Also, a last quarter moon can be used as a guidepost to Earth’s direction of motion in orbit around the sun.

In other words, when you look toward a last quarter moon high in the predawn sky, for example, you’re gazing out approximately along the path of Earth’s orbit, in a forward direction. The moon is moving in orbit around the sun with the Earth and never holds still. But, if we could somehow anchor the moon in space … tie it down, keep it still … Earth’s orbital speed of 18 miles per second would carry us across the space between us and the moon in only a few hours.

Want to read more about the last quarter moon as a guidepost for Earth’s motion? Astronomer Guy Ottewell talks about it here.

A great thing about using the moon as a guidepost to Earth’s motion is that you can do it anywhere … as, for example, in the photo below, from large cities.

Daytime sky. High small moon, left half visible, above conical-top water tower and tall tan brick chimney.

Ben Orlove wrote from New York City: “I was sitting in the roof garden of my building, and there was the moon, right in front of me. You were right, this is a perfect time to visualize … the Earth’s motion.”

As the moon orbits Earth, it changes phase in an orderly way. Read more: 4 keys to understanding moon phases

Bottom line: The moon reaches its last quarter phase on July 12, 2020, at 23:29 UTC. Translate UTC to your time. It will be the farthest quarter moon from Earth in 2020. In the coming week, watch for the moon to rise in the east in the hours after midnight, waning thinner each morning.



from EarthSky https://ift.tt/2ze0n1D
One half the moon's face in sunlight, lighted portion facing downward, left side marked N for north.

View at EarthSky Community Photos. | Dr Ski in Valencia, Philippines, caught the last quarter moon shortly after it rose around midnight on the morning of September 22, 2019. This moon phase is perfect for helping you envision the location of the sun … below your feet. Thanks, Dr Ski!

July’s last quarter moon is the most distant quarter moon of 2020. That’s because the instant of last quarter occurs only 4 hours after lunar apogee this month.

Read more: Year’s farthest quarter moon July 12

A last quarter moon appears half-lit by sunshine and half-immersed in its own shadow. It rises in the middle of the night, appears at its highest in the sky around dawn, and sets around midday.

A last quarter moon provides a great opportunity to think of yourself on a three-dimensional world in space. Watch for this moon just after moonrise, shortly after midnight. Then the lighted portion points downward, to the sun below your feet. Think of the last quarter moon as a mirror to the world you’re standing on. Think of yourself standing in the midst of Earth’s nightside, on the midnight portion of Earth.

On a last quarter moon, the lunar terminator – the shadow line dividing day and night – shows you where it’s sunset on the moon.

Craters and other features, including a short straight white line on a dark flat mare floor.

View at EarthSky Community Photos. | September 22, 2019, photo by Dr Ski. He wrote: “The moon’s southern limb at last quarter. The Straight Wall is either black or white depending on the angle of the sun’s rays. At lunar sunset (now), it’s white. Around full moon, Tycho is one of the easiest craters to find due to the impact rays emanating from it. It’s like the hub of a spoked wheel! At last quarter, Tycho becomes unremarkable. Clavius, on the other hand, becomes remarkable at high magnification.”

Labeled craters and mountain ranges at the edge between dark and light.

View at EarthSky Community Photos. | September 22, 2019, photo by Dr Ski. He wrote: “The Sea of Rains at last quarter. The lunar Alps and Apennines are bisected by the moon’s meridian. You can get an idea of the height of these mountains by how far they extend into the dark side of the terminator. At an elevation of over 5,000 meters [16,000 feet], the Apennines are twice as tall as the Alps.”

Also, a last quarter moon can be used as a guidepost to Earth’s direction of motion in orbit around the sun.

In other words, when you look toward a last quarter moon high in the predawn sky, for example, you’re gazing out approximately along the path of Earth’s orbit, in a forward direction. The moon is moving in orbit around the sun with the Earth and never holds still. But, if we could somehow anchor the moon in space … tie it down, keep it still … Earth’s orbital speed of 18 miles per second would carry us across the space between us and the moon in only a few hours.

Want to read more about the last quarter moon as a guidepost for Earth’s motion? Astronomer Guy Ottewell talks about it here.

A great thing about using the moon as a guidepost to Earth’s motion is that you can do it anywhere … as, for example, in the photo below, from large cities.

Daytime sky. High small moon, left half visible, above conical-top water tower and tall tan brick chimney.

Ben Orlove wrote from New York City: “I was sitting in the roof garden of my building, and there was the moon, right in front of me. You were right, this is a perfect time to visualize … the Earth’s motion.”

As the moon orbits Earth, it changes phase in an orderly way. Read more: 4 keys to understanding moon phases

Bottom line: The moon reaches its last quarter phase on July 12, 2020, at 23:29 UTC. Translate UTC to your time. It will be the farthest quarter moon from Earth in 2020. In the coming week, watch for the moon to rise in the east in the hours after midnight, waning thinner each morning.



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Curiosity Mars rover’s summer road trip has begun

Reddish ground under light sky with hill in distance, in jagged-edged photo.

Stitched together from 116 images, this view captured by NASA’s Curiosity Mars rover shows the path it will take in the summer of 2020 as it drives toward the next region it will be investigating, the “sulfate-bearing unit.” Image via NASA/ JPL-Caltech/ MSSS.

Via NASA

NASA’s Curiosity Mars rover has started a road trip that will continue through the summer across roughly a mile (1.6 km) of terrain. By trip’s end, the rover will be able to ascend to the next section of the 3-mile-tall (5-km-tall) Martian mountain – called Mount Sharp – that it’s been exploring since 2014, searching for conditions that may have supported ancient microbial life.

Located on the floor of Gale Crater, Mount Sharp is composed of sedimentary layers that built up over time. Each layer helps tell the story about how Mars changed from being more Earth-like – with lakes, streams and a thicker atmosphere – to the nearly-airless, freezing desert it is today.

The rover’s next stop is a part of the mountain called the “sulfate-bearing unit.” Sulfates, like gypsum and Epsom salts, usually form around water as it evaporates, and they are yet another clue to how the climate and prospects for life changed nearly 3 billion years ago.

Gray layers of rock in middle distance with textured, flatter ground closer up, in diagonal photo.

The goosebump-like textures in the center of this image were formed by water billions of years ago. NASA’s Curiosity Mars rover discovered them as it crested the slope of the Greenheugh Pediment on February 24, 2020 (the 2685th Martian day, or sol, of the mission). Image via NASA/ JPL-Caltech/ MSSS.

But between the rover and those sulfates lies a vast patch of sand that Curiosity must drive around to avoid getting stuck. Hence the mile-long road trip: Rover planners – who are commanding Curiosity from home rather than from their offices at NASA’s Jet Propulsion Laboratory (JPL) in Southern California – expect to reach the area in early fall, although the science team could decide to stop along the way to drill a sample or study any surprises they come across.

Depending on the landscape, Curiosity’s top speeds range between 82-328 feet (25-100 meters) per hour. Some of this summer road trip will be completed using the rover’s automated driving abilities, which enable Curiosity to find the safest paths forward on its own. Rover planners allow for this when they lack terrain imagery. (Planners hope for more autonomy in the future; in fact, you can help train an algorithm that identifies Martian drive paths.)

Matt Gildner is lead rover driver at JPL. He said:

Curiosity can’t drive entirely without humans in the loop. But it does have the ability to make simple decisions along the way to avoid large rocks or risky terrain. It stops if it doesn’t have enough information to complete a drive on its own.

In journeying to the “sulfate-bearing unit,” Curiosity leaves behind Mount Sharp’s “clay-bearing unit,” which the robotic scientist had been investigating on the lower side of the mountain since early 2019. Scientists are interested in the watery environment that formed this clay and whether it could have supported ancient microbes.

Extending across both the clay unit and the sulfate unit is a separate feature: the “Greenheugh Pediment,” a slope with a sandstone cap. It likely represents a major transition in the climate of Gale Crater. At some point, the lakes that filled the 96-mile-wide (154-kilometer-wide) crater disappeared, leaving behind sediments that eroded into the mountain we see today. The pediment formed later (though whether from wind or water erosion remains unknown); then windblown sand blanketed its surface, building into the sandstone cap.

The northern end of the pediment spans the clay region, and though the slope is steep, the rover’s team decided to ascend Greenheugh back in March for a preview of terrain they’ll see later in the mission. As Curiosity peeked over the top, scientists were surprised to find small bumps along the sandstone surface.

Layer of tan yellow sandstone on top of grayer land.

Stitched together from 28 images, NASA’s Curiosity Mars rover captured this view from “Greenheugh Pediment” on April 9, 2020, the 2,729th Martian day, or sol, of the mission. In the foreground is the pediment’s sandstone cap. At center is the “clay-bearing unit.” The floor of Gale Crater is in the distance. Image via NASA/ JPL-Caltech/ MSSS.

Alexander Bryk is a doctoral student at University of California, Berkeley who led the pediment detour. Bryk said:

Nodules like these require water in order to form. We found some in the windblown sandstone on top of the pediment and some just below the pediment. At some point after the pediment formed, water seems to have returned, altering the rock as it flowed through it.

These bumps may look familiar to Mars rover fans: One of Curiosity’s predecessors, the Opportunity rover, found similar geologic textures dubbed “blueberries” back in 2004. Nodules have become a familiar sight throughout Mount Sharp, though these newly discovered ones are different in composition from what Opportunity found. They suggest water was present in Gale long after the lakes disappeared and the mountain took its present shape. The discovery extends the period when the crater hosted conditions capable of supporting life, if it ever was present.

JPL’s Abigail Fraeman served as deputy project scientist for both missions. She said:

Curiosity was designed to go beyond Opportunity’s search for the history of water. We’re uncovering an ancient world that offered life a foothold for longer than we realized.

Bottom line: During summer 2020, the Mars Curiosity rover is making a mile-long (1.6 km long) journey around some deep sand so that it can explore higher up Mount Sharp.

Via NASA



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Reddish ground under light sky with hill in distance, in jagged-edged photo.

Stitched together from 116 images, this view captured by NASA’s Curiosity Mars rover shows the path it will take in the summer of 2020 as it drives toward the next region it will be investigating, the “sulfate-bearing unit.” Image via NASA/ JPL-Caltech/ MSSS.

Via NASA

NASA’s Curiosity Mars rover has started a road trip that will continue through the summer across roughly a mile (1.6 km) of terrain. By trip’s end, the rover will be able to ascend to the next section of the 3-mile-tall (5-km-tall) Martian mountain – called Mount Sharp – that it’s been exploring since 2014, searching for conditions that may have supported ancient microbial life.

Located on the floor of Gale Crater, Mount Sharp is composed of sedimentary layers that built up over time. Each layer helps tell the story about how Mars changed from being more Earth-like – with lakes, streams and a thicker atmosphere – to the nearly-airless, freezing desert it is today.

The rover’s next stop is a part of the mountain called the “sulfate-bearing unit.” Sulfates, like gypsum and Epsom salts, usually form around water as it evaporates, and they are yet another clue to how the climate and prospects for life changed nearly 3 billion years ago.

Gray layers of rock in middle distance with textured, flatter ground closer up, in diagonal photo.

The goosebump-like textures in the center of this image were formed by water billions of years ago. NASA’s Curiosity Mars rover discovered them as it crested the slope of the Greenheugh Pediment on February 24, 2020 (the 2685th Martian day, or sol, of the mission). Image via NASA/ JPL-Caltech/ MSSS.

But between the rover and those sulfates lies a vast patch of sand that Curiosity must drive around to avoid getting stuck. Hence the mile-long road trip: Rover planners – who are commanding Curiosity from home rather than from their offices at NASA’s Jet Propulsion Laboratory (JPL) in Southern California – expect to reach the area in early fall, although the science team could decide to stop along the way to drill a sample or study any surprises they come across.

Depending on the landscape, Curiosity’s top speeds range between 82-328 feet (25-100 meters) per hour. Some of this summer road trip will be completed using the rover’s automated driving abilities, which enable Curiosity to find the safest paths forward on its own. Rover planners allow for this when they lack terrain imagery. (Planners hope for more autonomy in the future; in fact, you can help train an algorithm that identifies Martian drive paths.)

Matt Gildner is lead rover driver at JPL. He said:

Curiosity can’t drive entirely without humans in the loop. But it does have the ability to make simple decisions along the way to avoid large rocks or risky terrain. It stops if it doesn’t have enough information to complete a drive on its own.

In journeying to the “sulfate-bearing unit,” Curiosity leaves behind Mount Sharp’s “clay-bearing unit,” which the robotic scientist had been investigating on the lower side of the mountain since early 2019. Scientists are interested in the watery environment that formed this clay and whether it could have supported ancient microbes.

Extending across both the clay unit and the sulfate unit is a separate feature: the “Greenheugh Pediment,” a slope with a sandstone cap. It likely represents a major transition in the climate of Gale Crater. At some point, the lakes that filled the 96-mile-wide (154-kilometer-wide) crater disappeared, leaving behind sediments that eroded into the mountain we see today. The pediment formed later (though whether from wind or water erosion remains unknown); then windblown sand blanketed its surface, building into the sandstone cap.

The northern end of the pediment spans the clay region, and though the slope is steep, the rover’s team decided to ascend Greenheugh back in March for a preview of terrain they’ll see later in the mission. As Curiosity peeked over the top, scientists were surprised to find small bumps along the sandstone surface.

Layer of tan yellow sandstone on top of grayer land.

Stitched together from 28 images, NASA’s Curiosity Mars rover captured this view from “Greenheugh Pediment” on April 9, 2020, the 2,729th Martian day, or sol, of the mission. In the foreground is the pediment’s sandstone cap. At center is the “clay-bearing unit.” The floor of Gale Crater is in the distance. Image via NASA/ JPL-Caltech/ MSSS.

Alexander Bryk is a doctoral student at University of California, Berkeley who led the pediment detour. Bryk said:

Nodules like these require water in order to form. We found some in the windblown sandstone on top of the pediment and some just below the pediment. At some point after the pediment formed, water seems to have returned, altering the rock as it flowed through it.

These bumps may look familiar to Mars rover fans: One of Curiosity’s predecessors, the Opportunity rover, found similar geologic textures dubbed “blueberries” back in 2004. Nodules have become a familiar sight throughout Mount Sharp, though these newly discovered ones are different in composition from what Opportunity found. They suggest water was present in Gale long after the lakes disappeared and the mountain took its present shape. The discovery extends the period when the crater hosted conditions capable of supporting life, if it ever was present.

JPL’s Abigail Fraeman served as deputy project scientist for both missions. She said:

Curiosity was designed to go beyond Opportunity’s search for the history of water. We’re uncovering an ancient world that offered life a foothold for longer than we realized.

Bottom line: During summer 2020, the Mars Curiosity rover is making a mile-long (1.6 km long) journey around some deep sand so that it can explore higher up Mount Sharp.

Via NASA



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Moon and Mars from midnight until dawn

The bright planets Jupiter and Saturn light the eastern half of the sky in early evening now. An even brighter planet, Venus, shines in the east at dawn. Meanwhile, in July 2020, Mars is the bright planet ascending in the east in the middle of the night. Mars isn’t as bright as Jupiter or Venus. And the Red Planet is nowhere close to Venus or Jupiter on the sky’s dome, but instead is found roughly midway between those other two brilliant orbs. The mornings of July 11 and 12, 2020 – from about midnight until dawn – are excellent times to watch for Mars. On these mornings, look first for the moon. The brilliant nearby “star” will be Mars.

Then, once you spot Mars, keep an eye on it in the weeks ahead.

Although the moon will move away from Mars after a few days, you should have little trouble finding Mars in the coming months. Brilliant Mars rules over a relatively “empty” realm of starry heavens, with no nearby bright stars to distract you from this fiery red planet.

Plus Mars will be rising earlier – and earlier – with each passing night. That’s because Earth is now about to catch up to Mars, and pass it, in the race of the planets around the sun. Mars is bright and very red now, and its due to get brighter in the coming months as it approaches its October opposition to the sun. At that time, Earth will be more or less between Mars and the sun. Mars will be opposite the sun in our sky, rising in the east at sundown, blazing very bright and fiery, visible from dusk to dawn.

Three telescopic views of the red planet Mars, showing a mottled red surface and a north polar cap.

View at EarthSky Community Photos. | Three days, three recent telescopic views of the Red Planet Mars by Gerardo Wright at Cancun Quintana Roo, México.

Venus and Jupiter rank as the 2nd- and 3rd-brightest celestial objects to light up the heavens, after the sun and moon. Yet, as Mars gets brighter in our sky day and day, it’ll ultimately supplant Jupiter as the 4th-brightest celestial body. That’ll happen in October 2020.

For now, Jupiter is enjoying its moment of glory, as the king planet shining at its brightest for the year.Read more: Jupiter at opposition on July 13-14, 2020

Read more: Saturn at opposition on July 20

Read more: Before 2020 ends, a great conjunction of Jupiter and Saturn

Venus adorns the eastern sky before sunrise in July 2020.

Venus lights up the eastern predawn/dawn sky in July 2020. If you’re up early enough around July 11 – when your morning sky is still dark – watch for the bright star Aldebaran in the constellation Taurus pairing up with Venus on the sky’s dome. Read more.

The moon travels in front of the constellations of the zodiac in an eastward direction, at the rate of about 13 degrees per day. To know which way is east, simply look at the waning moon in your morning sky. The lit side of the waning moon always points eastward (in the direction of sunrise).

So as the moon leaves Mars’ section of the zodiac, it’ll be heading for Venus, to rendezvous with the queen planet in about a week.

Slender waning crescent moon swings by Venus and then Mercury in the morning sky.

Watch for the waning crescent moon to sink downward day by day during the 3rd week of July 2020. It’ll sweep past both Venus and Mercury. Read more.

Bottom line: Jupiter dominates over the July evening sky, staying out from dusk until dawn. Venus, the sky’s brightest planet, lords over the eastern sky at dawn. Mars is roughly midway between Jupiter and Saturn. It’s near the moon on the mornings of July 11 and 12, 2020.

Read more: Year’s farthest quarter moon July 12



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

The bright planets Jupiter and Saturn light the eastern half of the sky in early evening now. An even brighter planet, Venus, shines in the east at dawn. Meanwhile, in July 2020, Mars is the bright planet ascending in the east in the middle of the night. Mars isn’t as bright as Jupiter or Venus. And the Red Planet is nowhere close to Venus or Jupiter on the sky’s dome, but instead is found roughly midway between those other two brilliant orbs. The mornings of July 11 and 12, 2020 – from about midnight until dawn – are excellent times to watch for Mars. On these mornings, look first for the moon. The brilliant nearby “star” will be Mars.

Then, once you spot Mars, keep an eye on it in the weeks ahead.

Although the moon will move away from Mars after a few days, you should have little trouble finding Mars in the coming months. Brilliant Mars rules over a relatively “empty” realm of starry heavens, with no nearby bright stars to distract you from this fiery red planet.

Plus Mars will be rising earlier – and earlier – with each passing night. That’s because Earth is now about to catch up to Mars, and pass it, in the race of the planets around the sun. Mars is bright and very red now, and its due to get brighter in the coming months as it approaches its October opposition to the sun. At that time, Earth will be more or less between Mars and the sun. Mars will be opposite the sun in our sky, rising in the east at sundown, blazing very bright and fiery, visible from dusk to dawn.

Three telescopic views of the red planet Mars, showing a mottled red surface and a north polar cap.

View at EarthSky Community Photos. | Three days, three recent telescopic views of the Red Planet Mars by Gerardo Wright at Cancun Quintana Roo, México.

Venus and Jupiter rank as the 2nd- and 3rd-brightest celestial objects to light up the heavens, after the sun and moon. Yet, as Mars gets brighter in our sky day and day, it’ll ultimately supplant Jupiter as the 4th-brightest celestial body. That’ll happen in October 2020.

For now, Jupiter is enjoying its moment of glory, as the king planet shining at its brightest for the year.Read more: Jupiter at opposition on July 13-14, 2020

Read more: Saturn at opposition on July 20

Read more: Before 2020 ends, a great conjunction of Jupiter and Saturn

Venus adorns the eastern sky before sunrise in July 2020.

Venus lights up the eastern predawn/dawn sky in July 2020. If you’re up early enough around July 11 – when your morning sky is still dark – watch for the bright star Aldebaran in the constellation Taurus pairing up with Venus on the sky’s dome. Read more.

The moon travels in front of the constellations of the zodiac in an eastward direction, at the rate of about 13 degrees per day. To know which way is east, simply look at the waning moon in your morning sky. The lit side of the waning moon always points eastward (in the direction of sunrise).

So as the moon leaves Mars’ section of the zodiac, it’ll be heading for Venus, to rendezvous with the queen planet in about a week.

Slender waning crescent moon swings by Venus and then Mercury in the morning sky.

Watch for the waning crescent moon to sink downward day by day during the 3rd week of July 2020. It’ll sweep past both Venus and Mercury. Read more.

Bottom line: Jupiter dominates over the July evening sky, staying out from dusk until dawn. Venus, the sky’s brightest planet, lords over the eastern sky at dawn. Mars is roughly midway between Jupiter and Saturn. It’s near the moon on the mornings of July 11 and 12, 2020.

Read more: Year’s farthest quarter moon July 12



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