aads

Small asteroid to sweep close this weekend

Very small asteroid 2018 WV1 on November 30 – slightly more than a day prior to its closest approach to Earth – via Northolt Branch Observatories.

Daniel Bamberger of Northolt Branch Observatories, a private observatory in Northolt, London, U.K., wrote late last night (November 30, 2018) about a small asteroid – just discovered – that will sweep extremely close to Earth Sunday morning, December 2, 2018. The asteroid designated 2018 WV1 will sweep closest at 03:11 UTC on Sunday. It will come within 0.09 lunar distances (32,911 km / 20,450 miles), making it the third-closest asteroid to pass Earth this year. Its estimated diameter is between 8.2 and 18.3 feet (2.5 and 5.6 meters). Bamgerger wrote:

2018 WV1 was found on November 29 at the Catalina Sky Survey in Arizona, USA. It will make a close encounter on Sunday morning, coming within 27,000 km (16,800 mi) from the Earth’s surface – closer than the geostationary satellites.

Besides its very close approach, 2018 WV1 is interesting for several reasons. One is its very low velocity relative to Earth: This makes it very likely that 2018 WV1 is a piece of lunar ejecta, a fragment of the moon that was ejected into space when a larger asteroid hit the moon a long time ago.

When 2018 WV1 was discovered, the initial orbit showed a 2% chance of hitting the Earth in early December. Luckily, that possibility was ruled out soon after.

Even if it had hit us, the object is too small to be a threat.

To help further refine its orbit, we have observed 2018 WV1 tonight from [Northolt Branch Observatories]. The asteroid was at a distance of 285,000 km from Earth at that time, and approaching, still a faint object at 19th magnitude.

According to The Watchers, since the beginning of 2018, observatories on Earth have detected 70 asteroids with flyby distance within 1 lunar distance.

Bottom line: Astronomers found asteroid 2018 WV1 on November 29. On December 2, it will pass closer to Earth than geosynchronous satellites.



from EarthSky https://ift.tt/2Q58DME

Very small asteroid 2018 WV1 on November 30 – slightly more than a day prior to its closest approach to Earth – via Northolt Branch Observatories.

Daniel Bamberger of Northolt Branch Observatories, a private observatory in Northolt, London, U.K., wrote late last night (November 30, 2018) about a small asteroid – just discovered – that will sweep extremely close to Earth Sunday morning, December 2, 2018. The asteroid designated 2018 WV1 will sweep closest at 03:11 UTC on Sunday. It will come within 0.09 lunar distances (32,911 km / 20,450 miles), making it the third-closest asteroid to pass Earth this year. Its estimated diameter is between 8.2 and 18.3 feet (2.5 and 5.6 meters). Bamgerger wrote:

2018 WV1 was found on November 29 at the Catalina Sky Survey in Arizona, USA. It will make a close encounter on Sunday morning, coming within 27,000 km (16,800 mi) from the Earth’s surface – closer than the geostationary satellites.

Besides its very close approach, 2018 WV1 is interesting for several reasons. One is its very low velocity relative to Earth: This makes it very likely that 2018 WV1 is a piece of lunar ejecta, a fragment of the moon that was ejected into space when a larger asteroid hit the moon a long time ago.

When 2018 WV1 was discovered, the initial orbit showed a 2% chance of hitting the Earth in early December. Luckily, that possibility was ruled out soon after.

Even if it had hit us, the object is too small to be a threat.

To help further refine its orbit, we have observed 2018 WV1 tonight from [Northolt Branch Observatories]. The asteroid was at a distance of 285,000 km from Earth at that time, and approaching, still a faint object at 19th magnitude.

According to The Watchers, since the beginning of 2018, observatories on Earth have detected 70 asteroids with flyby distance within 1 lunar distance.

Bottom line: Astronomers found asteroid 2018 WV1 on November 29. On December 2, it will pass closer to Earth than geosynchronous satellites.



from EarthSky https://ift.tt/2Q58DME

Golden virga at sunset

Image via Peter Lowenstein.

Peter Lowenstein in Mutare, Zimbabwe has contributed many amazing photos to EarthSky. Here’s what he told us about this image:

The first rains of the rainy season have fallen in Mutare over the past three days and humidity has been high. This afternoon cloud started to clear allowing the setting sun to emerge and shine brightly from a gap beneath it. Then something strange happened. At 10 minutes to 6:00, a patch of mist produced by condensation from moist cooling air began to reflect the setting sunlight to produce a bright spherical and then oblong apparition which floated for a minute or two directly above Hospital Hill. A short time later more widespread sunlit veils of condensation started to form and then developed into beautiful thin curtains of golden virga which for a few minutes shone brightly and remained suspended in the air.

Camera: Panasonic Lumix DMC TZ60 in sunset scene mode.

We’ve all seen virga, but maybe not known what it’s called. Virga is rain that evaporates before it hits the ground.

Thanks Peter!

Bottom line: Photo of virga in Mutare, Zimbabwe.

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



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Image via Peter Lowenstein.

Peter Lowenstein in Mutare, Zimbabwe has contributed many amazing photos to EarthSky. Here’s what he told us about this image:

The first rains of the rainy season have fallen in Mutare over the past three days and humidity has been high. This afternoon cloud started to clear allowing the setting sun to emerge and shine brightly from a gap beneath it. Then something strange happened. At 10 minutes to 6:00, a patch of mist produced by condensation from moist cooling air began to reflect the setting sunlight to produce a bright spherical and then oblong apparition which floated for a minute or two directly above Hospital Hill. A short time later more widespread sunlit veils of condensation started to form and then developed into beautiful thin curtains of golden virga which for a few minutes shone brightly and remained suspended in the air.

Camera: Panasonic Lumix DMC TZ60 in sunset scene mode.

We’ve all seen virga, but maybe not known what it’s called. Virga is rain that evaporates before it hits the ground.

Thanks Peter!

Bottom line: Photo of virga in Mutare, Zimbabwe.

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



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

Moon and Venus December 2 to 4

In the coming mornings – December 2, 3 and 4, 2018 – look eastward before sunrise for the moon and Venus. If your sky is clear, you can’t miss them! They’re always the brightest and second-brightest celestial bodies, respectively, to light up the night sky. Plus – around now – Venus is at its maximum brightness for this morning apparition, with its greatest illuminated extent falling around December 2.

The moon and Venus are so bright and beautiful that you’ll easily spot them at morning dawn. And, if you’re willing to get up an hour or two before sunrise, you can also see the bright star Arcturus to the north (left) of the moon and Venus, and the star Spica close to Venus.

If you peered at Venus through a telescope now, you’d find it in a waxing crescent phase. That’s because Venus passed between us and the sun on October 26, and its lighted half – or day side – is still facing mostly away from us. In early December, 2018, meanwhile, the moon is waning, and the phase of the waning crescent moon and waxing crescent Venus are almost identical. Both worlds are now showing us disks that are about one-quarter (25%) illuminated by sunshine. If you have a telescope, remember … you’ll get a crisper view of Venus’ phase at dawn, when this brilliant world has climbed higher above your horizon and its glare has been reduced by the breaking day.

Click here to find out the present phase of the moon and Venus

Venus in the predawn Tucson, Arizona sky on November 27, 2018. Eliot Herman wrote: “Venus is currently about as bright as it will be for this cycle, glowing in the eastern morning sky. Venus is amazingly bright! Crescent Venus inset captured with a Questar telescope, 50 mm lens and a Nikon D850.”

After today, the moon’s phase will continue to wane (get smaller) as the moon falls closer to the sunrise over the next several mornings. On December 5 and 6, 2018, the thin lunar crescent will swing by the planet Mercury, though Mercury will be quite hard to spot in the glow of morning twilight. Binoculars may help. See the chart below.

The good news is that Mercury is brightening day by day and, moreover, is coming up earlier by the day. So, by the middle of December, Mercury should become a fine morning object.

It’ll be tough to catch the slender crescent moon with the planet Mercury before sunrise December 5. But some of EarthSky’s eagle-eyed observers have surprised us before and might surprise us again! Submit your photo here, if you get one, or post in the comments below.

As the moon’s phase wanes, Venus’ phases waxes, as this world pulls ahead of us in its smaller, faster orbit, causing its illuminated or day side to slowly turn out way.

When Venus’ disk reaches its half-lit waxing quarter phase on January 6, 2019, this planet will be at its greatest elongation of 47 degrees west of the sun.

After Venus attains this milestone in the morning sky, this planet will begin slowly but surely sinking toward the sunrise. It’ll take many months to do this, as it moves ahead of us in orbit. Venus will finally pass more or less behind the sun from Earth – at what astronomers call superior conjunction – on August 14, 2019. At that juncture, Venus will transition out of the morning sky and into evening sky. See the diagram below.

Earth's and Venus' orbits

The Earth and Venus orbit the sun counterclockwise as seen to the north of the solar system plane. When Venus is to the east (left) of the Earth-sun line, we see Venus as an evening “star” in the west after sunset. After Venus reaches its inferior conjunction, Venus then moves to the west (right) of the Earth- sun line, appearing as a morning “star” in the east before sunrise.

Now back to the current month! The moon will turn new, to swing more or less between the sun and Earth, on December 7, 2018. At that time, the moon will transition from the morning to the evening sky.

Mercury and Venus are called inferior planets because they orbit the sun inside of Earth’s orbit. Although Venus is about twice Mercury’s distance from the sun, Venus is nonetheless the hotter of these two worlds. Climate does not depend on the sun alone but also on a planet’s atmosphere. Venus’ thick atmosphere creates a greenhouse effect that brings Venus’ surface temperature to 864 degrees Fahrenheit (462 degrees Celsius). Read more here.

Even though the moon and Earth are virtually the same distance from the sun, the moon’s daytime temperature is much hotter, and its nighttime temperature is much colder, than here on Earth. That’s because Earth has a protective atmosphere whereas the moon has no atmosphere of significance. Read more.

Bottom line: These next several mornings – December 2 to 4, 2018 – watch for the waning crescent moon to sweep by Venus, the solar system’s hottest planet. Some of you might also catch the moon near Mercury, the solar system’s innermost planet, on December 5.



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

In the coming mornings – December 2, 3 and 4, 2018 – look eastward before sunrise for the moon and Venus. If your sky is clear, you can’t miss them! They’re always the brightest and second-brightest celestial bodies, respectively, to light up the night sky. Plus – around now – Venus is at its maximum brightness for this morning apparition, with its greatest illuminated extent falling around December 2.

The moon and Venus are so bright and beautiful that you’ll easily spot them at morning dawn. And, if you’re willing to get up an hour or two before sunrise, you can also see the bright star Arcturus to the north (left) of the moon and Venus, and the star Spica close to Venus.

If you peered at Venus through a telescope now, you’d find it in a waxing crescent phase. That’s because Venus passed between us and the sun on October 26, and its lighted half – or day side – is still facing mostly away from us. In early December, 2018, meanwhile, the moon is waning, and the phase of the waning crescent moon and waxing crescent Venus are almost identical. Both worlds are now showing us disks that are about one-quarter (25%) illuminated by sunshine. If you have a telescope, remember … you’ll get a crisper view of Venus’ phase at dawn, when this brilliant world has climbed higher above your horizon and its glare has been reduced by the breaking day.

Click here to find out the present phase of the moon and Venus

Venus in the predawn Tucson, Arizona sky on November 27, 2018. Eliot Herman wrote: “Venus is currently about as bright as it will be for this cycle, glowing in the eastern morning sky. Venus is amazingly bright! Crescent Venus inset captured with a Questar telescope, 50 mm lens and a Nikon D850.”

After today, the moon’s phase will continue to wane (get smaller) as the moon falls closer to the sunrise over the next several mornings. On December 5 and 6, 2018, the thin lunar crescent will swing by the planet Mercury, though Mercury will be quite hard to spot in the glow of morning twilight. Binoculars may help. See the chart below.

The good news is that Mercury is brightening day by day and, moreover, is coming up earlier by the day. So, by the middle of December, Mercury should become a fine morning object.

It’ll be tough to catch the slender crescent moon with the planet Mercury before sunrise December 5. But some of EarthSky’s eagle-eyed observers have surprised us before and might surprise us again! Submit your photo here, if you get one, or post in the comments below.

As the moon’s phase wanes, Venus’ phases waxes, as this world pulls ahead of us in its smaller, faster orbit, causing its illuminated or day side to slowly turn out way.

When Venus’ disk reaches its half-lit waxing quarter phase on January 6, 2019, this planet will be at its greatest elongation of 47 degrees west of the sun.

After Venus attains this milestone in the morning sky, this planet will begin slowly but surely sinking toward the sunrise. It’ll take many months to do this, as it moves ahead of us in orbit. Venus will finally pass more or less behind the sun from Earth – at what astronomers call superior conjunction – on August 14, 2019. At that juncture, Venus will transition out of the morning sky and into evening sky. See the diagram below.

Earth's and Venus' orbits

The Earth and Venus orbit the sun counterclockwise as seen to the north of the solar system plane. When Venus is to the east (left) of the Earth-sun line, we see Venus as an evening “star” in the west after sunset. After Venus reaches its inferior conjunction, Venus then moves to the west (right) of the Earth- sun line, appearing as a morning “star” in the east before sunrise.

Now back to the current month! The moon will turn new, to swing more or less between the sun and Earth, on December 7, 2018. At that time, the moon will transition from the morning to the evening sky.

Mercury and Venus are called inferior planets because they orbit the sun inside of Earth’s orbit. Although Venus is about twice Mercury’s distance from the sun, Venus is nonetheless the hotter of these two worlds. Climate does not depend on the sun alone but also on a planet’s atmosphere. Venus’ thick atmosphere creates a greenhouse effect that brings Venus’ surface temperature to 864 degrees Fahrenheit (462 degrees Celsius). Read more here.

Even though the moon and Earth are virtually the same distance from the sun, the moon’s daytime temperature is much hotter, and its nighttime temperature is much colder, than here on Earth. That’s because Earth has a protective atmosphere whereas the moon has no atmosphere of significance. Read more.

Bottom line: These next several mornings – December 2 to 4, 2018 – watch for the waning crescent moon to sweep by Venus, the solar system’s hottest planet. Some of you might also catch the moon near Mercury, the solar system’s innermost planet, on December 5.



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

News digest – cancer survival, cervical screening, immunotherapy on the NHS and US targeted drug approval

Cancer survival in England still lagging behind the best

England hasn’t closed the gap on countries with the best cancer survival figures, despite improvements in cancer care and survival over the last 20 years. BBC News covered the new report, which warned that a “radical rethink” was required to help close the gap. The report highlights the need to diagnose more cancers earlier, as our news report details.

Immunotherapy drug now an option for some NHS patients with advanced skin cancer

The immunotherapy drug nivolumab (Opdivo) will now be an option for some patients with advanced melanoma skin cancer on the NHS in England. The drug works by boosting the immune system’s ability to kill cancer cells and will be given after surgery to help target any cancer cells left behind. Our news report has the details.

1 in 10 bowel cancer patients start treatment over a year after first noticing symptoms

Researchers found that men and women in Wales took the longest to contact their doctor after noticing a symptom or health change. And they also had the longest time from first noticing a change to starting treatment, which on average took 168 days. This compared to 145 days in England, 138 days in Northern Ireland and 120 days in Scotland. Our press release and ITV Wales have the story.

Targeted drug given green light for some NHS liver cancer patients

A targeted cancer drug will now be available for some adults with advanced liver cancer on the NHS in England and Wales. Regorafenib (Stivarga) was initially turned down by the National Institute for Health and Care Excellence (NICE) but will now be an option for a small group of patients whose livers are still working, but who can’t have surgery and have already been treated with a drug called sorafenib. Our news report has the story.

Cervical screening take-up continues to fall

More than a million women a year aren’t taking up the offer of cervical screening in England, reports The Sun. Women aged 25 to 64 are invited to cervical screening every 3 to 5 years, but 3 in 10 women aren’t attending, according to new figures.

How will Brexit affect the NHS?

BBC News take a look at the impact Brexit could have on the NHS, asking: will the NHS have enough staff, and will we run out of medicines?

Building a ‘Google Earth’ of cancer

The Evening Standard spoke to Cancer Research UK-funded chemist Professor Josephine Bunch, who’s leading one of our most ambitious Grand Challenge research projects. Bunch and her team are working to create personalised 3D maps of tumours. Our blog post explains how this might help improve cancer diagnosis and treatment in the future.

Rare cancer linked to textured breast implant

Textured breast implants have been linked to an increased risk of developing a rare cancer called anaplastic large cell lymphoma. The Guardian and BBC News covered the news, which was triggered after French surgeons were advised to stop using this type of implant by the health regulator, ANSM, while the link is being investigated. Any risks associated with this type of implant are still unclear but the UKMedicines and Healthcare products Regulatory Agency (MHRA) have estimated the risk of developing this rare cancer is around 1 in 24,000 women with implants will develop the cancer.

Cancer survival in Wales worse in poorer areas

New NHS figures reveal a growing gap between cancer survival in people living in deprived parts of Wales and those in richer areas, reports BBC News. While the number of cancer deaths have fallen in all regions between 2001 and 2017, rates have not fallen as steeply in the most deprived areas.

And finally

A new drug that can treat cancers fuelled by a rare gene fault no matter where they grow in the body has been granted accelerated approval by the US Food and Drug Administration. Larotrectinib (Vitrakvi) targets a rare gene fault that occurs in less than 1 in 100 tumours. It becomes the second treatment to be approved based on a molecular ‘fingerprint’ rather than where the cancer grows. The drug is also being considered for a licence in Europe, with a decision anticipated in 2019. NBC News covered the approval and our news report has a rundown of the latest clinical trial results.

Katie 



from Cancer Research UK – Science blog https://ift.tt/2PaKr6b

Cancer survival in England still lagging behind the best

England hasn’t closed the gap on countries with the best cancer survival figures, despite improvements in cancer care and survival over the last 20 years. BBC News covered the new report, which warned that a “radical rethink” was required to help close the gap. The report highlights the need to diagnose more cancers earlier, as our news report details.

Immunotherapy drug now an option for some NHS patients with advanced skin cancer

The immunotherapy drug nivolumab (Opdivo) will now be an option for some patients with advanced melanoma skin cancer on the NHS in England. The drug works by boosting the immune system’s ability to kill cancer cells and will be given after surgery to help target any cancer cells left behind. Our news report has the details.

1 in 10 bowel cancer patients start treatment over a year after first noticing symptoms

Researchers found that men and women in Wales took the longest to contact their doctor after noticing a symptom or health change. And they also had the longest time from first noticing a change to starting treatment, which on average took 168 days. This compared to 145 days in England, 138 days in Northern Ireland and 120 days in Scotland. Our press release and ITV Wales have the story.

Targeted drug given green light for some NHS liver cancer patients

A targeted cancer drug will now be available for some adults with advanced liver cancer on the NHS in England and Wales. Regorafenib (Stivarga) was initially turned down by the National Institute for Health and Care Excellence (NICE) but will now be an option for a small group of patients whose livers are still working, but who can’t have surgery and have already been treated with a drug called sorafenib. Our news report has the story.

Cervical screening take-up continues to fall

More than a million women a year aren’t taking up the offer of cervical screening in England, reports The Sun. Women aged 25 to 64 are invited to cervical screening every 3 to 5 years, but 3 in 10 women aren’t attending, according to new figures.

How will Brexit affect the NHS?

BBC News take a look at the impact Brexit could have on the NHS, asking: will the NHS have enough staff, and will we run out of medicines?

Building a ‘Google Earth’ of cancer

The Evening Standard spoke to Cancer Research UK-funded chemist Professor Josephine Bunch, who’s leading one of our most ambitious Grand Challenge research projects. Bunch and her team are working to create personalised 3D maps of tumours. Our blog post explains how this might help improve cancer diagnosis and treatment in the future.

Rare cancer linked to textured breast implant

Textured breast implants have been linked to an increased risk of developing a rare cancer called anaplastic large cell lymphoma. The Guardian and BBC News covered the news, which was triggered after French surgeons were advised to stop using this type of implant by the health regulator, ANSM, while the link is being investigated. Any risks associated with this type of implant are still unclear but the UKMedicines and Healthcare products Regulatory Agency (MHRA) have estimated the risk of developing this rare cancer is around 1 in 24,000 women with implants will develop the cancer.

Cancer survival in Wales worse in poorer areas

New NHS figures reveal a growing gap between cancer survival in people living in deprived parts of Wales and those in richer areas, reports BBC News. While the number of cancer deaths have fallen in all regions between 2001 and 2017, rates have not fallen as steeply in the most deprived areas.

And finally

A new drug that can treat cancers fuelled by a rare gene fault no matter where they grow in the body has been granted accelerated approval by the US Food and Drug Administration. Larotrectinib (Vitrakvi) targets a rare gene fault that occurs in less than 1 in 100 tumours. It becomes the second treatment to be approved based on a molecular ‘fingerprint’ rather than where the cancer grows. The drug is also being considered for a licence in Europe, with a decision anticipated in 2019. NBC News covered the approval and our news report has a rundown of the latest clinical trial results.

Katie 



from Cancer Research UK – Science blog https://ift.tt/2PaKr6b

December guide to the bright planets

It’ll be tough to catch the slender crescent moon with the planet Mercury before sunrise December 5. But some of EarthSky’s eagle-eyed observers have surprised us before and may surprise us again! Read more.

Click the name of a planet to learn more about its visibility in December 2018: Venus, Jupiter, Saturn, Mars and Mercury

The 2019 lunar calendars are here! Order yours before they’re gone. Makes a great gift.

Venus is the brightest planet, beaming mightily the east before sunrise. As December 2018 begins, Venus is shining at greatest brilliancy, its brightest for this morning apparition. Although Venus will remain a fixture of the morning sky until mid-August 2019, it’ll grow dimmer, by a bit, after early December. Even so, as always, Venus will rank as the 3rd-brightest celestial body, after the sun and moon!

The waning crescent moon will join Venus in the morning sky for several days, centered on or near December 3. If you’re up before dawn, you can also see the stars Arcturus and Spica accompanying the moon and the queen planet, as depicted on the sky chart above.

At mid-northern latitudes, Venus rises about 3 1/2 hours before sunrise throughout December.

At temperate latitudes in the Southern Hemisphere, Venus rises about two hours before sunup in early December. By the month’s end, that’ll increase to about 3 hours.

In mid-December 2018, look extra hard with the unaided eye or binoculars, and you just might spot the planet Jupiter near the horizon, and on line with Venus and Mercury. Read more.

Jupiter is the 2nd-brightest planet, after Venus. This planet exited the evening sky, and entered the morning sky, in late November. In the first week or two of December, Jupiter rises only a little while before the sun. It’ll be hard to see in the glare of morning twilight.

Jupiter will become easier to see before sunrise around mid-December, when it rises an hour or so before the sun. Around this time, Mercury reaches its greatest western (morning) elongation of 21 degrees from the rising sun. Because Mercury will rise before Jupiter does in mid-December, an imaginary line from Venus through Mercury may enable you to locate Jupiter near the horizon. See the above sky chart.

After mid-December, Jupiter will climb upward toward Mercury, as Mercury is sinking downward, toward Jupiter. Circle December 21 on your calendar, and watch for these two worlds to meet up for a close-knit conjunction. See the sky chart below.

Mercury and Jupiter are in conjunction on December 21, 2018. Very conveniently, these two worlds will easily fit within a single binocular field of view. Read more.

Jupiter rapidly climbs out of the glare of sunrise, coming up a solid two hours before the sun by the month’s end from most places worldwide. Mercury, though sinking sunward, will still rise a good hour before the sun on the last day of 2018. So, as the year draws to a close, watch for picturesque line-up of the waning crescent moon with Venus, Jupiter and Mercury about an hour before sunrise on December 31, as shown on the sky chart below.

On the last morning of the year – December 31, 2018 – watch for the moon to line up with the planets Venus, Jupiter and Mercury. Read more.

Mars and Saturn are the only two bright planets to appear the December 2018 evening sky – though Saturn, for the most part, only nominally so. Saturn sinks closer and closer to the sunset throughout December, and by mid-December will set too soon after the sun to be visible. Your best chance of spotting Saturn may be at dusk/nightfall on December 8 and 9, when the young waxing crescent moon swings rather close to Saturn on the sky’s dome. See the sky chart below.

Let the waxing crescent moon help guide your eye to the planet Saturn in December 2018. Saturn will disappear from the evening sky soon thereafter. Read more.

Fortunately, Mars remains bright and beautiful, shining more brilliantly than a 1st-magnitude star throughout December 2018. In December, Mars transits – reaches its highest point in the sky – at dusk in the Northern Hemisphere, yet before sunset in the Southern Hemisphere. Best of all, Mars stays out till around midnight in both the Northern and Southern Hemispheres.

Click here for a recommended sky almanac providing you with the transit times for Mars.

Watch for the moon to be in the vicinity of Mars for several evenings, centered on or near December 14. Fortunately, the moon will set before the peak hours of the Geminid meteor shower, centered around 2 in the morning on December 13 and 14. See the sky chart below.

On the expected peak night of the Geminids, the moon will be close to Mars on the sky’s dome. Mars’ setting at late night preludes the Geminid’s most prolific display of streaking meteors. Read more.

Saturn will swing over to the morning sky in January 2019, leaving Mars as the only bright planet to adorn the January 2019 evening sky.

Mercury, the innermost planet of the solar system, is a morning planet all month long in December 2018. Mercury might become visible before sunrise by the end of the first week of December. Look for Mercury beneath Venus, as shown on the sky chart below. By mid-December, Mercury rises about 90 minutes before the sun at mid-northern latitudes; from temperate latitudes in the Southern Hemisphere, it’s more like 75 minutes before sunrise. The crowning moment will come on the solstice, when Mercury and Jupiter have their conjunction on December 21.

Let Venus help guide your eye to Mercury .Venus rises in the predawn hours whereas Mercury follows Venus into the morning sky as nighttime gives way to morning dawn. Read more.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

Skywatcher, by Predrag Agatonovic.

Bottom line: In December 2018, Mars shines in the evening sky all month long. Saturn disappears in the sunset glare by about mid-month. Venus lights up the eastern sky before sunrise all month. Mercury and Jupiter join Venus in the morning sky around mid-December. Click here for recommended almanacs; they can help you know when the planets rise, transit and set in your sky.

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It’ll be tough to catch the slender crescent moon with the planet Mercury before sunrise December 5. But some of EarthSky’s eagle-eyed observers have surprised us before and may surprise us again! Read more.

Click the name of a planet to learn more about its visibility in December 2018: Venus, Jupiter, Saturn, Mars and Mercury

The 2019 lunar calendars are here! Order yours before they’re gone. Makes a great gift.

Venus is the brightest planet, beaming mightily the east before sunrise. As December 2018 begins, Venus is shining at greatest brilliancy, its brightest for this morning apparition. Although Venus will remain a fixture of the morning sky until mid-August 2019, it’ll grow dimmer, by a bit, after early December. Even so, as always, Venus will rank as the 3rd-brightest celestial body, after the sun and moon!

The waning crescent moon will join Venus in the morning sky for several days, centered on or near December 3. If you’re up before dawn, you can also see the stars Arcturus and Spica accompanying the moon and the queen planet, as depicted on the sky chart above.

At mid-northern latitudes, Venus rises about 3 1/2 hours before sunrise throughout December.

At temperate latitudes in the Southern Hemisphere, Venus rises about two hours before sunup in early December. By the month’s end, that’ll increase to about 3 hours.

In mid-December 2018, look extra hard with the unaided eye or binoculars, and you just might spot the planet Jupiter near the horizon, and on line with Venus and Mercury. Read more.

Jupiter is the 2nd-brightest planet, after Venus. This planet exited the evening sky, and entered the morning sky, in late November. In the first week or two of December, Jupiter rises only a little while before the sun. It’ll be hard to see in the glare of morning twilight.

Jupiter will become easier to see before sunrise around mid-December, when it rises an hour or so before the sun. Around this time, Mercury reaches its greatest western (morning) elongation of 21 degrees from the rising sun. Because Mercury will rise before Jupiter does in mid-December, an imaginary line from Venus through Mercury may enable you to locate Jupiter near the horizon. See the above sky chart.

After mid-December, Jupiter will climb upward toward Mercury, as Mercury is sinking downward, toward Jupiter. Circle December 21 on your calendar, and watch for these two worlds to meet up for a close-knit conjunction. See the sky chart below.

Mercury and Jupiter are in conjunction on December 21, 2018. Very conveniently, these two worlds will easily fit within a single binocular field of view. Read more.

Jupiter rapidly climbs out of the glare of sunrise, coming up a solid two hours before the sun by the month’s end from most places worldwide. Mercury, though sinking sunward, will still rise a good hour before the sun on the last day of 2018. So, as the year draws to a close, watch for picturesque line-up of the waning crescent moon with Venus, Jupiter and Mercury about an hour before sunrise on December 31, as shown on the sky chart below.

On the last morning of the year – December 31, 2018 – watch for the moon to line up with the planets Venus, Jupiter and Mercury. Read more.

Mars and Saturn are the only two bright planets to appear the December 2018 evening sky – though Saturn, for the most part, only nominally so. Saturn sinks closer and closer to the sunset throughout December, and by mid-December will set too soon after the sun to be visible. Your best chance of spotting Saturn may be at dusk/nightfall on December 8 and 9, when the young waxing crescent moon swings rather close to Saturn on the sky’s dome. See the sky chart below.

Let the waxing crescent moon help guide your eye to the planet Saturn in December 2018. Saturn will disappear from the evening sky soon thereafter. Read more.

Fortunately, Mars remains bright and beautiful, shining more brilliantly than a 1st-magnitude star throughout December 2018. In December, Mars transits – reaches its highest point in the sky – at dusk in the Northern Hemisphere, yet before sunset in the Southern Hemisphere. Best of all, Mars stays out till around midnight in both the Northern and Southern Hemispheres.

Click here for a recommended sky almanac providing you with the transit times for Mars.

Watch for the moon to be in the vicinity of Mars for several evenings, centered on or near December 14. Fortunately, the moon will set before the peak hours of the Geminid meteor shower, centered around 2 in the morning on December 13 and 14. See the sky chart below.

On the expected peak night of the Geminids, the moon will be close to Mars on the sky’s dome. Mars’ setting at late night preludes the Geminid’s most prolific display of streaking meteors. Read more.

Saturn will swing over to the morning sky in January 2019, leaving Mars as the only bright planet to adorn the January 2019 evening sky.

Mercury, the innermost planet of the solar system, is a morning planet all month long in December 2018. Mercury might become visible before sunrise by the end of the first week of December. Look for Mercury beneath Venus, as shown on the sky chart below. By mid-December, Mercury rises about 90 minutes before the sun at mid-northern latitudes; from temperate latitudes in the Southern Hemisphere, it’s more like 75 minutes before sunrise. The crowning moment will come on the solstice, when Mercury and Jupiter have their conjunction on December 21.

Let Venus help guide your eye to Mercury .Venus rises in the predawn hours whereas Mercury follows Venus into the morning sky as nighttime gives way to morning dawn. Read more.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

Skywatcher, by Predrag Agatonovic.

Bottom line: In December 2018, Mars shines in the evening sky all month long. Saturn disappears in the sunset glare by about mid-month. Venus lights up the eastern sky before sunrise all month. Mercury and Jupiter join Venus in the morning sky around mid-December. Click here for recommended almanacs; they can help you know when the planets rise, transit and set in your sky.

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When is my earliest sunset?

Adrian Strand captured this photo on a beach in northwest England.

Adrian Strand captured this photo on a beach in northwest England.

The winter solstice is the shortest day. It offers the shortest period of daylight. But, unless you live close to the Arctic Circle or Antarctic Circle, your earliest sunsets aren’t on or even near the solstice itself. Instead, your earliest sunsets will come before the winter solstice. The exact date of earliest sunset depends on your latitude. If you live in the southernmost U.S., or a comparable latitude (say, around 25 or 26 degrees N. latitude), your earliest sunsets are in late November. If you’re farther north – say, around 40 degrees N. latitude – your earliest sunsets are around December 7.

Stephen Aman shares his map of the United States that lists the dates of the year’s earliest sunset for various latitudes. Thank you Stephen!

And if you live in the Southern Hemisphere, your earliest sunrises are coming around now. Southern Hemisphere? Click here.

Why isn’t the earliest sunset on the year’s shortest day? To understand it, try thinking about it in terms of solar noon or midday, the time midway between sunrise and sunset, when the sun reaches its highest point for the day.

A clock ticks off exactly 24 hours from one noon to the next. But the actual days – as measured by the spin of the Earth – are rarely exactly 24 hours long.

So the exact time of solar noon, as measured by Earth’s spin, shifts in a seasonal way. If you measured Earth’s spin from one solar noon to the next, you’d find that – around the time of the December solstice – the time period between consecutive solar noons is actually half a minute longer than 24 hours.

So – two weeks before the solstice, for example – the sun reaches its noontime position at 11:52 a.m. local standard time. Two weeks later – on the winter solstice – the sun reaches its noontime position at 11:59 a.m. That’s 7 minutes later.

The later clock time for solar noon also means a later clock time for sunrise and sunset.

Click here for the December 2018 calendar, giving you the clock time for solar noon (check the solar noon box).

The result: earlier sunsets before the winter solstice and increasingly later sunrises for a few weeks after the winter solstice.

The exact date of earliest sunset varies with latitude. But the sequence is always the same. For the Northern Hemisphere, earliest sunset in early December, winter solstice, latest sunrise in early January.

In early December, the Southern Hemisphere is approaching its summer solstice. Sunset on that part of Earth will continue coming later until early July. Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich QLD Australia. Visit Phil Rettke on Facebook.

In early December, the Southern Hemisphere is approaching its summer solstice. Sunset on that part of Earth will continue coming later until early January. Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich, Queensland, Australia.

Meanwhile, if you’re in the Southern Hemisphere, take nearly everything we say here and apply it to your winter solstice in June. For the Southern Hemisphere, the earliest sunsets come prior to the winter solstice, which is typically around June 21. The latest sunrises occur after the June winter solstice.

During the month of December, it’s nearly summer in the Southern Hemisphere; the summer solstice comes this month for that hemisphere. So sunsets and sunrises are shifting in a similar way. For both hemispheres, the sequence in summer is: earliest sunrises before the summer solstice, then the summer solstice itself, then latest sunsets after the summer solstice.

As always, things get tricky if you look closely. Assuming you’re at a mid-temperate latitude, the earliest sunset for the Northern Hemisphere – and earliest sunrise for the Southern Hemisphere – come about two weeks before the December solstice, and the latest sunrise/latest sunset happen about two weeks after.

But at the other end of the year, in June and July, the time period is not equivalent. Again assuming a mid-temperate latitude, the earliest sunrise for the Northern Hemisphere – and earliest sunset for the Southern Hemisphere – comes only about one week before the June solstice, and the latest sunset/latest sunrise happens about one week after.

The time difference is due to the fact that the December solstice occurs when Earth is near its perihelion – or closest point to the sun – around which time we’re moving fastest in orbit. Meanwhile, the June solstice occurs when Earth is near aphelion – our farthest point from the sun – around which time we’re moving at our slowest in orbit.

View larger. Computed position of the sun looking eastward at the same time each morning from the Northern Hemisphere. December solstice point at lower right and June solstice point at upper left. Solar days are longer than 24 hours long at the solstices, yet less than 24 hours long at the equinoxes. Roughly midway between a solstice and an equinox, or vice versa, the solar day is exactly 24 hours long.

View larger. Computed position of the sun looking eastward at the same time each morning from the Northern Hemisphere. December solstice point at lower right and June solstice point at upper left. Solar days are longer than 24 hours long at the solstices, yet less than 24 hours long at the equinoxes. Roughly midway between a solstice and an equinox, or vice versa, the solar day is exactly 24 hours long.

In short, the earliest sunset/winter solstice/latest sunrise and earliest sunrise/summer solstice/latest sunset phenomena are due to the fact that true solar days are longer than 24 hours long for several weeks before and after the solstices. At and around the solstices, the Earth must rotate farther on its axis for the sun to return to its daily noontime position, primarily because the sun is appreciably north or south of the Earth’s equator.

However, perihelion accentuates the effect around the December solstice, giving a day length of 24 hours 30 seconds. And aphelion lessens the effect around the June solstice, giving a day length of 24 hours 13 seconds.

Bottom line: The earliest sunsets and latest sunrises don’t come on the winter solstice, the shortest day of the year. Instead, earliest sunsets come some weeks before the winter solstice. Latest sunrises come some weeks after it.

Here are more details about the earliest sunsets.



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Adrian Strand captured this photo on a beach in northwest England.

Adrian Strand captured this photo on a beach in northwest England.

The winter solstice is the shortest day. It offers the shortest period of daylight. But, unless you live close to the Arctic Circle or Antarctic Circle, your earliest sunsets aren’t on or even near the solstice itself. Instead, your earliest sunsets will come before the winter solstice. The exact date of earliest sunset depends on your latitude. If you live in the southernmost U.S., or a comparable latitude (say, around 25 or 26 degrees N. latitude), your earliest sunsets are in late November. If you’re farther north – say, around 40 degrees N. latitude – your earliest sunsets are around December 7.

Stephen Aman shares his map of the United States that lists the dates of the year’s earliest sunset for various latitudes. Thank you Stephen!

And if you live in the Southern Hemisphere, your earliest sunrises are coming around now. Southern Hemisphere? Click here.

Why isn’t the earliest sunset on the year’s shortest day? To understand it, try thinking about it in terms of solar noon or midday, the time midway between sunrise and sunset, when the sun reaches its highest point for the day.

A clock ticks off exactly 24 hours from one noon to the next. But the actual days – as measured by the spin of the Earth – are rarely exactly 24 hours long.

So the exact time of solar noon, as measured by Earth’s spin, shifts in a seasonal way. If you measured Earth’s spin from one solar noon to the next, you’d find that – around the time of the December solstice – the time period between consecutive solar noons is actually half a minute longer than 24 hours.

So – two weeks before the solstice, for example – the sun reaches its noontime position at 11:52 a.m. local standard time. Two weeks later – on the winter solstice – the sun reaches its noontime position at 11:59 a.m. That’s 7 minutes later.

The later clock time for solar noon also means a later clock time for sunrise and sunset.

Click here for the December 2018 calendar, giving you the clock time for solar noon (check the solar noon box).

The result: earlier sunsets before the winter solstice and increasingly later sunrises for a few weeks after the winter solstice.

The exact date of earliest sunset varies with latitude. But the sequence is always the same. For the Northern Hemisphere, earliest sunset in early December, winter solstice, latest sunrise in early January.

In early December, the Southern Hemisphere is approaching its summer solstice. Sunset on that part of Earth will continue coming later until early July. Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich QLD Australia. Visit Phil Rettke on Facebook.

In early December, the Southern Hemisphere is approaching its summer solstice. Sunset on that part of Earth will continue coming later until early January. Photo of sunset with crepuscular rays by Phil Rettke Photography in Ipswich, Queensland, Australia.

Meanwhile, if you’re in the Southern Hemisphere, take nearly everything we say here and apply it to your winter solstice in June. For the Southern Hemisphere, the earliest sunsets come prior to the winter solstice, which is typically around June 21. The latest sunrises occur after the June winter solstice.

During the month of December, it’s nearly summer in the Southern Hemisphere; the summer solstice comes this month for that hemisphere. So sunsets and sunrises are shifting in a similar way. For both hemispheres, the sequence in summer is: earliest sunrises before the summer solstice, then the summer solstice itself, then latest sunsets after the summer solstice.

As always, things get tricky if you look closely. Assuming you’re at a mid-temperate latitude, the earliest sunset for the Northern Hemisphere – and earliest sunrise for the Southern Hemisphere – come about two weeks before the December solstice, and the latest sunrise/latest sunset happen about two weeks after.

But at the other end of the year, in June and July, the time period is not equivalent. Again assuming a mid-temperate latitude, the earliest sunrise for the Northern Hemisphere – and earliest sunset for the Southern Hemisphere – comes only about one week before the June solstice, and the latest sunset/latest sunrise happens about one week after.

The time difference is due to the fact that the December solstice occurs when Earth is near its perihelion – or closest point to the sun – around which time we’re moving fastest in orbit. Meanwhile, the June solstice occurs when Earth is near aphelion – our farthest point from the sun – around which time we’re moving at our slowest in orbit.

View larger. Computed position of the sun looking eastward at the same time each morning from the Northern Hemisphere. December solstice point at lower right and June solstice point at upper left. Solar days are longer than 24 hours long at the solstices, yet less than 24 hours long at the equinoxes. Roughly midway between a solstice and an equinox, or vice versa, the solar day is exactly 24 hours long.

View larger. Computed position of the sun looking eastward at the same time each morning from the Northern Hemisphere. December solstice point at lower right and June solstice point at upper left. Solar days are longer than 24 hours long at the solstices, yet less than 24 hours long at the equinoxes. Roughly midway between a solstice and an equinox, or vice versa, the solar day is exactly 24 hours long.

In short, the earliest sunset/winter solstice/latest sunrise and earliest sunrise/summer solstice/latest sunset phenomena are due to the fact that true solar days are longer than 24 hours long for several weeks before and after the solstices. At and around the solstices, the Earth must rotate farther on its axis for the sun to return to its daily noontime position, primarily because the sun is appreciably north or south of the Earth’s equator.

However, perihelion accentuates the effect around the December solstice, giving a day length of 24 hours 30 seconds. And aphelion lessens the effect around the June solstice, giving a day length of 24 hours 13 seconds.

Bottom line: The earliest sunsets and latest sunrises don’t come on the winter solstice, the shortest day of the year. Instead, earliest sunsets come some weeks before the winter solstice. Latest sunrises come some weeks after it.

Here are more details about the earliest sunsets.



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Take 2 trips around Earth, from space

The European Space Agency (ESA) released this timelapse video this month (November 19, 2018) in celebration of the launch 20 years ago of the International Space Station (ISS). ESA astronaut Alexander Gerst acquired the images for the timelapse in October 2018. At just under 15 minutes, it’s the longest-yet continuous timelapse from space.

The video takes you from Tunisia across Beijing and through Australia in two trips around the world. You can follow the Station’s location on the map at the top right of the screen beside annotations on the photos themselves. Because the map is a two-dimensional representation of Earth’s globe, the ground track of the ISS appears to be wavy.

This timelapse comprises more than 21,000 images of Earth captured by Gerst from the ISS orbiting at its 250-mile (400-km) altitude about our world’s surface. The video is shown 12.5 times faster than actual speed.

At 18,000 miles (28,800 km) per hour, it only takes 90 minutes for the ISS to make a complete circuit of Earth, so the video shows the world passing from day to night and back again twice. The darker regions on the map shows where night is on Earth.

You can see numerous flashes of lightning during night time. That’s lightning from storms and is common on our planet. Also at night, look for stars rising above the horizon through the faint glow of the atmosphere still illuminated by the sun.

Here’s more from ESA:

As the Space Station flies into the night the solar wings rotate to get ready to capture the next rays of sunlight when the orbital outpost moves outside of the shadow of Earth. On the right is Japan’s cargo spacecraft HTV-7 that was docked with the International Space Station until November 7, 2018.

The white panels visible top left from 05:30 are the International Space Station’s radiators that pump ammonia to exchange heat and keep the facilities and astronauts inside at the right temperature.

At 06:55 the International Space Station flies over Europe starting with Portugal and Spain. Each new orbit of Earth sees the Space Station fly slightly more to the west than the orbit before.

Bottom line: The longest-yet timelapse from space, from ISS astronaut Alexander Gerst. Take two trips around the Earth in just under 15 minutes.

Via ESA

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



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The European Space Agency (ESA) released this timelapse video this month (November 19, 2018) in celebration of the launch 20 years ago of the International Space Station (ISS). ESA astronaut Alexander Gerst acquired the images for the timelapse in October 2018. At just under 15 minutes, it’s the longest-yet continuous timelapse from space.

The video takes you from Tunisia across Beijing and through Australia in two trips around the world. You can follow the Station’s location on the map at the top right of the screen beside annotations on the photos themselves. Because the map is a two-dimensional representation of Earth’s globe, the ground track of the ISS appears to be wavy.

This timelapse comprises more than 21,000 images of Earth captured by Gerst from the ISS orbiting at its 250-mile (400-km) altitude about our world’s surface. The video is shown 12.5 times faster than actual speed.

At 18,000 miles (28,800 km) per hour, it only takes 90 minutes for the ISS to make a complete circuit of Earth, so the video shows the world passing from day to night and back again twice. The darker regions on the map shows where night is on Earth.

You can see numerous flashes of lightning during night time. That’s lightning from storms and is common on our planet. Also at night, look for stars rising above the horizon through the faint glow of the atmosphere still illuminated by the sun.

Here’s more from ESA:

As the Space Station flies into the night the solar wings rotate to get ready to capture the next rays of sunlight when the orbital outpost moves outside of the shadow of Earth. On the right is Japan’s cargo spacecraft HTV-7 that was docked with the International Space Station until November 7, 2018.

The white panels visible top left from 05:30 are the International Space Station’s radiators that pump ammonia to exchange heat and keep the facilities and astronauts inside at the right temperature.

At 06:55 the International Space Station flies over Europe starting with Portugal and Spain. Each new orbit of Earth sees the Space Station fly slightly more to the west than the orbit before.

Bottom line: The longest-yet timelapse from space, from ISS astronaut Alexander Gerst. Take two trips around the Earth in just under 15 minutes.

Via ESA

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



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