Rise of carbon dioxide in the atmosphere continues unabated

Image via NOAA.

The amount of carbon dioxide (CO2) in Earth’s atmosphere continues to rise, say scientists. On June 4, 2020, scientists from NOAA and Scripps Institution of Oceanography announced that atmospheric CO2 measured at Mauna Loa Observatory in Hawaii reached a seasonal peak of 417.1 parts per million for 2020 in May, the highest monthly reading ever recorded.

Meanwhile, a new study, published May 29,2020 in Geology, concludes that today’s carbon dioxide (CO2) levels are higher than they have been for the past 23 million years. The study’s CO2 timeline revealed no evidence for any fluctuations in CO2 that might be comparable to the dramatic CO2 increase of the present day, suggesting that today’s abrupt greenhouse disruption is unique across recent geologic history. Read more about the study here.

CO2 measurements at Mauna Loa in Hawaii began in 1958, initiating what has become the longest unbroken record of CO2 measurements in the world. The Mauna Loa observatory is a benchmark sampling location for CO2. Perched on a barren volcano in the middle of the Pacific Ocean, the observatory is ideally situated for sampling well-mixed air – undisturbed by the influence of local pollution sources or vegetation – that represents the global background for the northern hemisphere. The Mauna Loa data, together with measurements from sampling stations around the world, are incorporated into NOAA’s Global Greenhouse Gas Reference Network, a foundational research dataset for international climate scientists. Image via NOAA.

Pieter Tans, senior scientist with NOAA’s Global Monitoring Laboratory. Tans said in a statement:

Progress in emissions reductions is not visible in the CO2 record. We continue to commit our planet – for centuries or longer – to more global heating, sea level rise, and extreme weather events every year.

If humans were to suddenly stop emitting CO2, it would take thousands of years for our CO2 emissions so far to be absorbed into the deep ocean and atmospheric CO2 to return to pre-industrial levels.

Image via NOAA/ Scripps Institution of Oceanography.

According to the NOAA report, this year’s peak value was 2.4 parts per million (ppm) higher than the 2019 peak of 414.7 ppm recorded in May 2019. NOAA scientists reported a May average of 417.1 ppm. Scripps scientists reported an May average of 417.2 ppm. Monthly carbon dioxide (CO2) values at Mauna Loa first breached the 400 ppm threshold in 2014, and are now at levels not experienced by the atmosphere in several million years.

The rate of increase during 2020 does not appear to reflect reduction in pollution emissions due to the sharp, worldwide economic slowdown in response to the coronavirus pandemic. The reason, says NOAA, is that the drop in emissions would need to be large enough to stand out from natural CO2 variability, caused by how plants and soils respond to seasonal and annual variations of temperature, humidity, soil moisture, etc. These natural variations are large, and so far the emissions reductions associated with COVID19 do not stand out. If emissions reductions of 20 to 30 percent were sustained for six to 12 months, then the rate of increase of CO2 measured at Mauna Loa would be slowed.

Geochemist Ralph Keeling runs the Scripps Oceanography program at Mauna Loa. He said:

People may be surprised to hear that the response to the coronavirus outbreak hasn’t done more to influence CO2 levels. But the buildup of CO2 is a bit like trash in a landfill. As we keep emitting, it keeps piling up. The crisis has slowed emissions, but not enough to show up perceptibly at Mauna Loa. What will matter much more is the trajectory we take coming out of this situation.

Even though terrestrial plants and the global ocean absorb an amount of CO2 equivalent to about half of the 40 billion tons of CO2 pollution emitted by humans each year, the rate of CO2 increase in the atmosphere has been steadily accelerating. In the 1960s, the annual growth averaged about 0.8 ppm per year. It doubled to 1.6 ppm per year in the 1980s and remained steady at 1.5 ppm per year in the 1990s. The average growth rate again surged to 2.0 ppm per year in the 2000s, and increased to 2.4 ppm per year during the last decade.

Tans said:

There is abundant and conclusive evidence that the acceleration is caused by increased emissions … Well-understood physics tells us that the increasing levels of greenhouse gases are heating Earth’s surface, melting ice and accelerating sea-level rise. If we do not stop greenhouse gases from rising further, especially CO2, large regions of the planet will become uninhabitable.

This graph depicts the last four complete years of the Mauna Loa carbon dioxide record plus the current year. The dashed red lines represent the monthly mean values, centered on the middle of each month. The black lines represent the same, after correction for the average seasonal cycle. Image via NOAA

Bottom line: A NOAA report released in June 2020 says that atmospheric carbon dioxide (CO2) measured at Hawaii’s Mauna Loa Observatory for May 2020 was the highest monthly reading ever recorded.

Source: A 23 m.y. record of low atmospheric CO2

Via The Geological Society of America

Via NOAA

from EarthSky https://ift.tt/3hbvL5R

Image via NOAA.

The amount of carbon dioxide (CO2) in Earth’s atmosphere continues to rise, say scientists. On June 4, 2020, scientists from NOAA and Scripps Institution of Oceanography announced that atmospheric CO2 measured at Mauna Loa Observatory in Hawaii reached a seasonal peak of 417.1 parts per million for 2020 in May, the highest monthly reading ever recorded.

Meanwhile, a new study, published May 29,2020 in Geology, concludes that today’s carbon dioxide (CO2) levels are higher than they have been for the past 23 million years. The study’s CO2 timeline revealed no evidence for any fluctuations in CO2 that might be comparable to the dramatic CO2 increase of the present day, suggesting that today’s abrupt greenhouse disruption is unique across recent geologic history. Read more about the study here.

CO2 measurements at Mauna Loa in Hawaii began in 1958, initiating what has become the longest unbroken record of CO2 measurements in the world. The Mauna Loa observatory is a benchmark sampling location for CO2. Perched on a barren volcano in the middle of the Pacific Ocean, the observatory is ideally situated for sampling well-mixed air – undisturbed by the influence of local pollution sources or vegetation – that represents the global background for the northern hemisphere. The Mauna Loa data, together with measurements from sampling stations around the world, are incorporated into NOAA’s Global Greenhouse Gas Reference Network, a foundational research dataset for international climate scientists. Image via NOAA.

Pieter Tans, senior scientist with NOAA’s Global Monitoring Laboratory. Tans said in a statement:

Progress in emissions reductions is not visible in the CO2 record. We continue to commit our planet – for centuries or longer – to more global heating, sea level rise, and extreme weather events every year.

If humans were to suddenly stop emitting CO2, it would take thousands of years for our CO2 emissions so far to be absorbed into the deep ocean and atmospheric CO2 to return to pre-industrial levels.

Image via NOAA/ Scripps Institution of Oceanography.

According to the NOAA report, this year’s peak value was 2.4 parts per million (ppm) higher than the 2019 peak of 414.7 ppm recorded in May 2019. NOAA scientists reported a May average of 417.1 ppm. Scripps scientists reported an May average of 417.2 ppm. Monthly carbon dioxide (CO2) values at Mauna Loa first breached the 400 ppm threshold in 2014, and are now at levels not experienced by the atmosphere in several million years.

The rate of increase during 2020 does not appear to reflect reduction in pollution emissions due to the sharp, worldwide economic slowdown in response to the coronavirus pandemic. The reason, says NOAA, is that the drop in emissions would need to be large enough to stand out from natural CO2 variability, caused by how plants and soils respond to seasonal and annual variations of temperature, humidity, soil moisture, etc. These natural variations are large, and so far the emissions reductions associated with COVID19 do not stand out. If emissions reductions of 20 to 30 percent were sustained for six to 12 months, then the rate of increase of CO2 measured at Mauna Loa would be slowed.

Geochemist Ralph Keeling runs the Scripps Oceanography program at Mauna Loa. He said:

People may be surprised to hear that the response to the coronavirus outbreak hasn’t done more to influence CO2 levels. But the buildup of CO2 is a bit like trash in a landfill. As we keep emitting, it keeps piling up. The crisis has slowed emissions, but not enough to show up perceptibly at Mauna Loa. What will matter much more is the trajectory we take coming out of this situation.

Even though terrestrial plants and the global ocean absorb an amount of CO2 equivalent to about half of the 40 billion tons of CO2 pollution emitted by humans each year, the rate of CO2 increase in the atmosphere has been steadily accelerating. In the 1960s, the annual growth averaged about 0.8 ppm per year. It doubled to 1.6 ppm per year in the 1980s and remained steady at 1.5 ppm per year in the 1990s. The average growth rate again surged to 2.0 ppm per year in the 2000s, and increased to 2.4 ppm per year during the last decade.

Tans said:

There is abundant and conclusive evidence that the acceleration is caused by increased emissions … Well-understood physics tells us that the increasing levels of greenhouse gases are heating Earth’s surface, melting ice and accelerating sea-level rise. If we do not stop greenhouse gases from rising further, especially CO2, large regions of the planet will become uninhabitable.

This graph depicts the last four complete years of the Mauna Loa carbon dioxide record plus the current year. The dashed red lines represent the monthly mean values, centered on the middle of each month. The black lines represent the same, after correction for the average seasonal cycle. Image via NOAA

Bottom line: A NOAA report released in June 2020 says that atmospheric carbon dioxide (CO2) measured at Hawaii’s Mauna Loa Observatory for May 2020 was the highest monthly reading ever recorded.

Source: A 23 m.y. record of low atmospheric CO2

Via The Geological Society of America

Via NOAA

from EarthSky https://ift.tt/3hbvL5R

Happy World Oceans Day 2020

The Pacific Ocean, viewed from the International Space Station. Image via NASA. Longing for the sea? Check out these photos from the EarthSky community.

World Oceans Day has been celebrated every year on June 8 since 1992. It’s a day to raise awareness about how we’re connected – no matter where we live – to the oceans, and about what we can do to protect ocean habitats. This year’s theme – announced by United Nations World Oceans Day 2020 – is Innovation for a Sustainable Ocean. The day is meant to focus on new ideas, techniques, and products for a more sustainable management of our oceans’ resources.

It’s widely recognized that Earth’s oceans are critical to human survival. More than half the oxygen in our atmosphere is generated via photosynthesis by phytoplankton and seaweed in oceans. Millions of people depend on fish and other marine animals for food. Research in some marine organisms have led to the development of new medications; for example, the drug remdesivir, an antiviral medication currently being evaluated in clinical trials as a treatment for Covid-19, contains compounds that are found in some sea sponges. Earth’s climate is regulated by ocean currents known as global conveyor belts.

Perhaps the best reason we’ve seen to celebrate and protect Earth’s oceans comes from the 2013 video below, featuring Sylvia Earle, who is a National Geographic Society Explorer-in-Residence and perhaps the world’s most recognized living oceanographer. In the video, among other things, Earle says:

I think of the ocean as the blue heart of the planet.

And she says:

We, too, are sea creatures.

Canada made the original proposal for World Oceans Day in 1992 at the Earth Summit in Rio de Janeiro, Brazil. The day was unofficially celebrated on June 8 until 2008, when the United Nations officially recognized it. Since then, World Oceans Day has been coordinated internationally by The Ocean Project and the World Ocean Network. These organizations say they have had greater success and global participation each year.

We know that human activities have adversely affected the health of oceans: pollution, over-fishing, seawater acidification due to increased carbon dioxide, ocean warming, habitat destruction. There is so much to do to repair the damage.

In 2020, organizations such as aquariums and marine research institutions – which would otherwise host public events for World Oceans Day – are unable to do it due to the Covid-19 pandemic. Some online events and cleanups are listed at the World Oceans Day website.

There are also things you can do on your own, on this day or any other. If you live near an ocean, perhaps join a shoreline cleanup (with appropriate social distancing during this time of pandemic).

Even if you’re not near the sea, you can encourage your seafood retailers and favorite seafood restaurants to to source their seafood more sustainably (Monterey Bay Aquarium’s Seafood Watch program is a terrific resource).

And we can all reduce our use of plastics with reusable shopping bags and refillable water bottles, and by using biodegradable products over plastic.

Plus we can contemplate the sea, and teach our children to love it. Show your kids the sea creature below, just announced a couple of months ago … perhaps the longest living animal ever recorded! Happy World Oceans Day, everyone!

The thin, white spiral in this aerial image is a living creature, reported on in April 2020 by scientists. They said this 150-foot (46-meter) siphonophore might be the the longest animal ever recorded. The massive gelatinous siphonophore was discovered during a month-long scientific expedition exploring the submarine canyons near Ningaloo in the Indian Ocean off the coast of Western Australia. Read more and see a video.

Bottom line: June 8, 2020, is World Oceans Day. This year’s theme is Innovation for a Sustainable Ocean. You can find some online events for June 8 at the World Oceans Day website.

Longing for the sea? Check out these photos from the EarthSky community.

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

The Pacific Ocean, viewed from the International Space Station. Image via NASA. Longing for the sea? Check out these photos from the EarthSky community.

World Oceans Day has been celebrated every year on June 8 since 1992. It’s a day to raise awareness about how we’re connected – no matter where we live – to the oceans, and about what we can do to protect ocean habitats. This year’s theme – announced by United Nations World Oceans Day 2020 – is Innovation for a Sustainable Ocean. The day is meant to focus on new ideas, techniques, and products for a more sustainable management of our oceans’ resources.

It’s widely recognized that Earth’s oceans are critical to human survival. More than half the oxygen in our atmosphere is generated via photosynthesis by phytoplankton and seaweed in oceans. Millions of people depend on fish and other marine animals for food. Research in some marine organisms have led to the development of new medications; for example, the drug remdesivir, an antiviral medication currently being evaluated in clinical trials as a treatment for Covid-19, contains compounds that are found in some sea sponges. Earth’s climate is regulated by ocean currents known as global conveyor belts.

Perhaps the best reason we’ve seen to celebrate and protect Earth’s oceans comes from the 2013 video below, featuring Sylvia Earle, who is a National Geographic Society Explorer-in-Residence and perhaps the world’s most recognized living oceanographer. In the video, among other things, Earle says:

I think of the ocean as the blue heart of the planet.

And she says:

We, too, are sea creatures.

Canada made the original proposal for World Oceans Day in 1992 at the Earth Summit in Rio de Janeiro, Brazil. The day was unofficially celebrated on June 8 until 2008, when the United Nations officially recognized it. Since then, World Oceans Day has been coordinated internationally by The Ocean Project and the World Ocean Network. These organizations say they have had greater success and global participation each year.

We know that human activities have adversely affected the health of oceans: pollution, over-fishing, seawater acidification due to increased carbon dioxide, ocean warming, habitat destruction. There is so much to do to repair the damage.

In 2020, organizations such as aquariums and marine research institutions – which would otherwise host public events for World Oceans Day – are unable to do it due to the Covid-19 pandemic. Some online events and cleanups are listed at the World Oceans Day website.

There are also things you can do on your own, on this day or any other. If you live near an ocean, perhaps join a shoreline cleanup (with appropriate social distancing during this time of pandemic).

Even if you’re not near the sea, you can encourage your seafood retailers and favorite seafood restaurants to to source their seafood more sustainably (Monterey Bay Aquarium’s Seafood Watch program is a terrific resource).

And we can all reduce our use of plastics with reusable shopping bags and refillable water bottles, and by using biodegradable products over plastic.

Plus we can contemplate the sea, and teach our children to love it. Show your kids the sea creature below, just announced a couple of months ago … perhaps the longest living animal ever recorded! Happy World Oceans Day, everyone!

The thin, white spiral in this aerial image is a living creature, reported on in April 2020 by scientists. They said this 150-foot (46-meter) siphonophore might be the the longest animal ever recorded. The massive gelatinous siphonophore was discovered during a month-long scientific expedition exploring the submarine canyons near Ningaloo in the Indian Ocean off the coast of Western Australia. Read more and see a video.

Bottom line: June 8, 2020, is World Oceans Day. This year’s theme is Innovation for a Sustainable Ocean. You can find some online events for June 8 at the World Oceans Day website.

Longing for the sea? Check out these photos from the EarthSky community.

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

Longing for the sea? Check out these photos

View at EarthSky Community Photos. | Cindy Chai wrote from the North Pacific Ocean: “Smell the sea and feel the sky! During the COVID 19 period, many people can’t get out of their home due to lock down, so I think I’m lucky because I still get to see the ocean everyday due to my job on sea.” Thank you, Cindy.

World Oceans Day – a global day of ocean celebration – takes place every year on June 8. The World Ocean Project first organized the day as a time to celebrate the oceans and take steps to protect ocean health. This year’s theme is Innovation for a Sustainable Ocean.

Find out more about World Oceans Day 2020

View at EarthSky Community Photos. | Kim Cronan of Wabasso Beach, Florida, sent in this photo and wrote, “Taken while enjoying a typically gorgeous December day in South Florida and the Atlantic Ocean’s amazing shades of blue.” Thanks, Kim!

View at EarthSky Community Photos. | Kevan Hubbard at Seaton Carew in County Durham, England, wrote: “A window in the clouds with rain heading to the Yorkshire Moors.” Thank you, Kevan.

Paulo P. Pereira of Torres Vedras, Lisbon, Portugal, captured this image.

Overlooking the Atlantic Ocean from the Georgia coast, by Greg Hogan.

West Bay, Dorset, at sunset. Image via Roger Morgan.

“Into the Bay of Bengal” by Karthik Easvur.

Tommy Richardsen Photography in Nordreisa, in northern Norway, captured this image of ice melting in the Norwegian Sea in May 2018. He wrote: “Magic of May. Close to 7 hours of good weather conditions for photography, rain, fog, mist, sunlight and crazy clouds, all one can ask for. :)” D810, 15mm.

Leo Carrillo State Beach, Malibu, California. Photo via Kristal Alaimo-Moritz Klear.

Twilight at Waimanalo Beach, Oahu, Hawaii, on June 4, 2017, via Chantel Dunlap.

Summer showers near Galveston, Texas, by Brett Stone.

San Francisco Bay by Matt Snow.

From Reykjanes Peninsula in Iceland, by Vladimir Zlvkovic.

York Beach, Maine, by Kevin Pratt.

From the Great Ocean Road in Australia by Malck Coolen Photography.

“Seawater inlet of Indian Ocean where two seas of different texture meet!” by Sima Sweet.

Atlantic Ocean, off the coast of Cape Breton Island, Canada, by Tynski Photographic.

Glenn Miles Photography took this photo from the north coast of Northern Ireland. Thank you, Glenn.

Maine coast at sunrise by John Gravell.

Sunset in Truro, Massachusetts, looking toward Provincetown, by John Gravell.

“Loggerhead sea turtle tracks at sunrise on Florida’s beautiful east coast.” Photo via Rachel Smith. Thanks Rachel!

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

Bottom line: Ocean photos from EarthSky friends across the globe in celebration of World Oceans Day 2020.

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

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

View at EarthSky Community Photos. | Cindy Chai wrote from the North Pacific Ocean: “Smell the sea and feel the sky! During the COVID 19 period, many people can’t get out of their home due to lock down, so I think I’m lucky because I still get to see the ocean everyday due to my job on sea.” Thank you, Cindy.

World Oceans Day – a global day of ocean celebration – takes place every year on June 8. The World Ocean Project first organized the day as a time to celebrate the oceans and take steps to protect ocean health. This year’s theme is Innovation for a Sustainable Ocean.

Find out more about World Oceans Day 2020

View at EarthSky Community Photos. | Kim Cronan of Wabasso Beach, Florida, sent in this photo and wrote, “Taken while enjoying a typically gorgeous December day in South Florida and the Atlantic Ocean’s amazing shades of blue.” Thanks, Kim!

View at EarthSky Community Photos. | Kevan Hubbard at Seaton Carew in County Durham, England, wrote: “A window in the clouds with rain heading to the Yorkshire Moors.” Thank you, Kevan.

Paulo P. Pereira of Torres Vedras, Lisbon, Portugal, captured this image.

Overlooking the Atlantic Ocean from the Georgia coast, by Greg Hogan.

West Bay, Dorset, at sunset. Image via Roger Morgan.

“Into the Bay of Bengal” by Karthik Easvur.

Tommy Richardsen Photography in Nordreisa, in northern Norway, captured this image of ice melting in the Norwegian Sea in May 2018. He wrote: “Magic of May. Close to 7 hours of good weather conditions for photography, rain, fog, mist, sunlight and crazy clouds, all one can ask for. :)” D810, 15mm.

Leo Carrillo State Beach, Malibu, California. Photo via Kristal Alaimo-Moritz Klear.

Twilight at Waimanalo Beach, Oahu, Hawaii, on June 4, 2017, via Chantel Dunlap.

Summer showers near Galveston, Texas, by Brett Stone.

San Francisco Bay by Matt Snow.

From Reykjanes Peninsula in Iceland, by Vladimir Zlvkovic.

York Beach, Maine, by Kevin Pratt.

From the Great Ocean Road in Australia by Malck Coolen Photography.

“Seawater inlet of Indian Ocean where two seas of different texture meet!” by Sima Sweet.

Atlantic Ocean, off the coast of Cape Breton Island, Canada, by Tynski Photographic.

Glenn Miles Photography took this photo from the north coast of Northern Ireland. Thank you, Glenn.

Maine coast at sunrise by John Gravell.

Sunset in Truro, Massachusetts, looking toward Provincetown, by John Gravell.

“Loggerhead sea turtle tracks at sunrise on Florida’s beautiful east coast.” Photo via Rachel Smith. Thanks Rachel!

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

Bottom line: Ocean photos from EarthSky friends across the globe in celebration of World Oceans Day 2020.

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

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

Video: 2 minutes of cool ocean facts

In celebration of 2020’s World Oceans Day, NOAA released this video with a bunch of cool facts about our planet’s oceans. Did you know, for example, that Australia’s Great Barrier Reef is the largest living structure on Earth and can be seen from the moon?

Bottom line: Two-minute video with facts about Earth’s oceans.

Via NOAA

from EarthSky https://ift.tt/3h7c2UY

In celebration of 2020’s World Oceans Day, NOAA released this video with a bunch of cool facts about our planet’s oceans. Did you know, for example, that Australia’s Great Barrier Reef is the largest living structure on Earth and can be seen from the moon?

Bottom line: Two-minute video with facts about Earth’s oceans.

Via NOAA

from EarthSky https://ift.tt/3h7c2UY

Middle of eclipse season June 20

Various stages of an annular solar eclipse from Brocken Inaglory via Wikimedia Commons.

Eclipses of the new moon and full moon don’t occur every month, because the moon’s orbital plane is inclined by about 5 degrees to the plane of the ecliptic (Earth’s orbital plane). But the moon’s orbital path does intersect the Earth’s orbital plane at two points called nodes. Whenever these lunar nodes point directly at the sun, it marks the midpoint of the eclipse season. The lunar nodes line up with the sun in periods of about 173.3 days, or nearly 10 days shy of six calendar months.

The middle of the eclipse season (when the line of nodes points directly the sun) last took place on December 30, 2019. The middle of the eclipse season will next occur on June 20, 2020, and then – after that – on December 11, 2020.

Whenever the lunar nodes point directly at the sun, it marks the midpoint of the approximate 35-day eclipse season. In the year 2020, the middle of the eclipse season occurs on June 20, 2020, and then again on December 11, 2020. Image via Go Science Go.

An eclipse season lasts for approximately 35 days, and any new moon or full moon occurring within this time period will undergo an eclipse. Given that the lunar month (period of time between successive new moons or successive full moons) is about 29.5 days long, a minimum of two eclipses (one solar and one lunar, in either order), or a maximum of three eclipses (either lunar/solar/lunar, or solar/lunar/solar) can take place in one eclipse season.

Eclipses are all about alignments. In a solar eclipse, the sun, moon and Earth line up, with the moon in the middle. Image via NASA.

In a lunar eclipse, the sun, Earth and moon line up, with the Earth in the middle. Image via NASA.

Most often, there are only two eclipses in one eclipse season. For three eclipses to occur, the first one has to come quite early in the eclipse season to allow for a third eclipse near the end. For the first time since the year 2018, we’ll have three eclipses in one eclipse season in 2020. We won’t have three eclipses in one eclipse season again until the year 2029.

The year 2020:

June 5, 2020: Penumbral lunar eclipse
June 21, 2020: Annular solar eclipse
July 5, 2020: Penumbral lunar eclipse

Read more: How often are there 3 eclipses in a month?

If an eclipse happens at or near the mid-point of the eclipse season, as the upcoming solar eclipse on June 21st does, then we’ll have a central eclipse. If it’s a solar eclipse, the central eclipse presents either a total or annular eclipse of the sun; or if it’s a lunar eclipse, the central eclipse features a total eclipse of the moon. If the eclipse falls near the beginning or the end of the eclipse season, it’s either a penumbral eclipse of the moon or small partial eclipse of the sun.

Read more: Annular eclipse of the sun on June 21, 2020

Because the lunar eclipses occur so early and so late in the June/July 2020 eclipse season, the lunar eclipses on June 5, 2020, and July 5, 2020, will be extremely faint and hard-to-see penumbral lunar eclipses. See the illustration of these eclipses below.

The next eclipse season in June/July 2020 will showcase three eclipses (lunar/solar/lunar). Image via Wikipedia.

On the other hand, the solar eclipse on June 21, 2020, which takes place almost dead center in the eclipse season, will present a central eclipse, exhibiting an annular eclipse of the sun. See diagram above.

Thirty-eight eclipse seasons (19 eclipse years) are almost exactly commensurate to 223 lunar months, a period of 18 years and 11 1/3 days (four intervening leap years) or 18 years and 10 1/3 days (5 intervening leap years). Therefore, the eclipses coming up in June/July 2038 display similar geometries to those in June/July 2020. This 223-lunar-month period of time is known as the Saros.

The year 2020:

June 5, 2020: Penumbral lunar eclipse
June 21, 2020: Annular solar eclipse
July 5, 2020: Penumbral lunar eclipse

The year 2038:

June 17, 2038: Penumbral lunar eclipse
July 2, 2038: Annular solar eclipse
July 16, 2038: Penumbral lunar eclipse

Interestingly, the Sar or Half Saros, representing a period of 111.5 lunar months (9 years and 5 2/3 days), gives us alternating eclipses (solar/lunar/solar) of similar character. Contrast the years 2020 and 2038 listed above with the years 2029 and 2047 listed below.

Many people are familiar with the Saros period of 223 lunar months (18.03 years), whereby a similar progression of eclipses takes place in one eclipse season (lunar/solar/lunar). Less well known, the Sar or Half Saros of 111.5 lunar months (9.015 years) also presents 3 eclipses in one eclipse season, though in alternate order (solar/lunar/solar). Image via Wikipedia.

The year 2029:

June 12, 2029: Partial solar eclipse
June 26, 2029: Total lunar eclipse
July 11, 2029; Partial solar eclipse

The year 2047:

June 23, 2047: Partial solar eclipse
July 7, 2047: Total lunar eclipse
July 22, 2047: Partial solar eclipse

The eclipse master Fred Espenak tells us a Saros series can last anywhere from 1,226 to 1,550 years and is made up of 69 to 87 eclipses. A Saros series, whether it be solar or lunar, always starts off with skimpy eclipses and ends with skimpy eclipses. The middle of a Saros series brings about the closest alignment of the three celestial bodies – Earth, sun and moon – whereby they line up almost perfectly in space.

In any eclipse season where there are three eclipses, the first and third eclipses are meager productions whereas the middle eclipse is a highly visible central eclipse. And in any Saros series, the early and late eclipses are also paltry at best, whereas the middle part of a Saros series presents central eclipses.

Here’s something that may surprise you: Any eclipse happening early in an eclipse season always occurs late in a Saros series – and vice versa. For example, let’s look at the upcoming three-eclipse season in June/July 2020:

The year 2020:

June 5, 2020: Penumbral lunar eclipse
June 21, 2020: Annular solar eclipse
July 5, 2020: Penumbral lunar eclipse

The first eclipse of the eclipse season on June 5, 2020, belongs to Lunar Saros 111 and presents the 67th of 71 eclipses in this Saros series. Yet, the third and final eclipse of the eclipse season on July 5, 2020, belongs to Lunar Saros 149, and features the third of 71 eclipses in this particular Saros series.

Unsurprisingly, perhaps, the second (or middle) eclipse of the eclipse season on June 21, 2020, is the 36th of 70 eclipses in Solar Saros 137.

The plane of the moon’s orbit is inclined at 5 degrees to the plane of Earth’s orbit around the sun (the ecliptic). In this diagram, however, the ecliptic is portrayed as the sun’s apparent annual path in front of the constellations of the zodiac. The moon’s orbit intersects the ecliptic at two points called nodes (labeled here as N1 and N2). It’s the middle of the eclipse season whenever this line of nodes points directly at the sun. In the above diagram, the line of nodes does not point at the sun.

Bottom line: The middle of the eclipse season falls on June 20, 2020, and this eclipse season produces three eclipses (lunar/solar/lunar), though only the second of these three eclipses – the annular “ring of fire” eclipse on June 21, 2020 – will produce any real theatrics on the great stage of the sky.

from EarthSky https://ift.tt/2UkWFi1

Various stages of an annular solar eclipse from Brocken Inaglory via Wikimedia Commons.

Eclipses of the new moon and full moon don’t occur every month, because the moon’s orbital plane is inclined by about 5 degrees to the plane of the ecliptic (Earth’s orbital plane). But the moon’s orbital path does intersect the Earth’s orbital plane at two points called nodes. Whenever these lunar nodes point directly at the sun, it marks the midpoint of the eclipse season. The lunar nodes line up with the sun in periods of about 173.3 days, or nearly 10 days shy of six calendar months.

The middle of the eclipse season (when the line of nodes points directly the sun) last took place on December 30, 2019. The middle of the eclipse season will next occur on June 20, 2020, and then – after that – on December 11, 2020.

Whenever the lunar nodes point directly at the sun, it marks the midpoint of the approximate 35-day eclipse season. In the year 2020, the middle of the eclipse season occurs on June 20, 2020, and then again on December 11, 2020. Image via Go Science Go.

An eclipse season lasts for approximately 35 days, and any new moon or full moon occurring within this time period will undergo an eclipse. Given that the lunar month (period of time between successive new moons or successive full moons) is about 29.5 days long, a minimum of two eclipses (one solar and one lunar, in either order), or a maximum of three eclipses (either lunar/solar/lunar, or solar/lunar/solar) can take place in one eclipse season.

Eclipses are all about alignments. In a solar eclipse, the sun, moon and Earth line up, with the moon in the middle. Image via NASA.

In a lunar eclipse, the sun, Earth and moon line up, with the Earth in the middle. Image via NASA.

Most often, there are only two eclipses in one eclipse season. For three eclipses to occur, the first one has to come quite early in the eclipse season to allow for a third eclipse near the end. For the first time since the year 2018, we’ll have three eclipses in one eclipse season in 2020. We won’t have three eclipses in one eclipse season again until the year 2029.

The year 2020:

June 5, 2020: Penumbral lunar eclipse
June 21, 2020: Annular solar eclipse
July 5, 2020: Penumbral lunar eclipse

Read more: How often are there 3 eclipses in a month?

If an eclipse happens at or near the mid-point of the eclipse season, as the upcoming solar eclipse on June 21st does, then we’ll have a central eclipse. If it’s a solar eclipse, the central eclipse presents either a total or annular eclipse of the sun; or if it’s a lunar eclipse, the central eclipse features a total eclipse of the moon. If the eclipse falls near the beginning or the end of the eclipse season, it’s either a penumbral eclipse of the moon or small partial eclipse of the sun.

Read more: Annular eclipse of the sun on June 21, 2020

Because the lunar eclipses occur so early and so late in the June/July 2020 eclipse season, the lunar eclipses on June 5, 2020, and July 5, 2020, will be extremely faint and hard-to-see penumbral lunar eclipses. See the illustration of these eclipses below.

The next eclipse season in June/July 2020 will showcase three eclipses (lunar/solar/lunar). Image via Wikipedia.

On the other hand, the solar eclipse on June 21, 2020, which takes place almost dead center in the eclipse season, will present a central eclipse, exhibiting an annular eclipse of the sun. See diagram above.

Thirty-eight eclipse seasons (19 eclipse years) are almost exactly commensurate to 223 lunar months, a period of 18 years and 11 1/3 days (four intervening leap years) or 18 years and 10 1/3 days (5 intervening leap years). Therefore, the eclipses coming up in June/July 2038 display similar geometries to those in June/July 2020. This 223-lunar-month period of time is known as the Saros.

The year 2020:

June 5, 2020: Penumbral lunar eclipse
June 21, 2020: Annular solar eclipse
July 5, 2020: Penumbral lunar eclipse

The year 2038:

June 17, 2038: Penumbral lunar eclipse
July 2, 2038: Annular solar eclipse
July 16, 2038: Penumbral lunar eclipse

Interestingly, the Sar or Half Saros, representing a period of 111.5 lunar months (9 years and 5 2/3 days), gives us alternating eclipses (solar/lunar/solar) of similar character. Contrast the years 2020 and 2038 listed above with the years 2029 and 2047 listed below.

Many people are familiar with the Saros period of 223 lunar months (18.03 years), whereby a similar progression of eclipses takes place in one eclipse season (lunar/solar/lunar). Less well known, the Sar or Half Saros of 111.5 lunar months (9.015 years) also presents 3 eclipses in one eclipse season, though in alternate order (solar/lunar/solar). Image via Wikipedia.

The year 2029:

June 12, 2029: Partial solar eclipse
June 26, 2029: Total lunar eclipse
July 11, 2029; Partial solar eclipse

The year 2047:

June 23, 2047: Partial solar eclipse
July 7, 2047: Total lunar eclipse
July 22, 2047: Partial solar eclipse

The eclipse master Fred Espenak tells us a Saros series can last anywhere from 1,226 to 1,550 years and is made up of 69 to 87 eclipses. A Saros series, whether it be solar or lunar, always starts off with skimpy eclipses and ends with skimpy eclipses. The middle of a Saros series brings about the closest alignment of the three celestial bodies – Earth, sun and moon – whereby they line up almost perfectly in space.

In any eclipse season where there are three eclipses, the first and third eclipses are meager productions whereas the middle eclipse is a highly visible central eclipse. And in any Saros series, the early and late eclipses are also paltry at best, whereas the middle part of a Saros series presents central eclipses.

Here’s something that may surprise you: Any eclipse happening early in an eclipse season always occurs late in a Saros series – and vice versa. For example, let’s look at the upcoming three-eclipse season in June/July 2020:

The year 2020:

June 5, 2020: Penumbral lunar eclipse
June 21, 2020: Annular solar eclipse
July 5, 2020: Penumbral lunar eclipse

The first eclipse of the eclipse season on June 5, 2020, belongs to Lunar Saros 111 and presents the 67th of 71 eclipses in this Saros series. Yet, the third and final eclipse of the eclipse season on July 5, 2020, belongs to Lunar Saros 149, and features the third of 71 eclipses in this particular Saros series.

Unsurprisingly, perhaps, the second (or middle) eclipse of the eclipse season on June 21, 2020, is the 36th of 70 eclipses in Solar Saros 137.

The plane of the moon’s orbit is inclined at 5 degrees to the plane of Earth’s orbit around the sun (the ecliptic). In this diagram, however, the ecliptic is portrayed as the sun’s apparent annual path in front of the constellations of the zodiac. The moon’s orbit intersects the ecliptic at two points called nodes (labeled here as N1 and N2). It’s the middle of the eclipse season whenever this line of nodes points directly at the sun. In the above diagram, the line of nodes does not point at the sun.

Bottom line: The middle of the eclipse season falls on June 20, 2020, and this eclipse season produces three eclipses (lunar/solar/lunar), though only the second of these three eclipses – the annular “ring of fire” eclipse on June 21, 2020 – will produce any real theatrics on the great stage of the sky.

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Jupiter gives us Pluto in 2020

Mosaic image of Pluto and its largest moon Charon, captured around the time the New Horizons spacecraft swept closest to them on July 14, 2015. Image via NASA/ JHUAPL/ SwRI.

The year 2020 is exceptional for Jupiter and Pluto. These two worlds are having a triple conjunction this year. They’ll come together, move apart, and come together again three times in 2020. The first conjunction took place on April 5. The second one will come on June 30, and the final one on November 12. Because all of these Jupiter-Pluto conjunctions happen when these two planets are actually visible in our night sky (as opposed to being lost in the sun’s glare), this year’s Jupiter-Pluto alignment may be the best for centuries to come.

This year, very bright Jupiter and very faint Pluto will remain near each other throughout the year, closely aligned in front of the constellation Sagittarius. Pluto requires a telescope to be seen. No telescope? Try NASA’s Night Sky Network to find star parties and/or astronomy clubs near you.

And you don’t need a telescope to use your imagination. Throughout 2020, dazzling Jupiter will enable us to envision Pluto with the mind’s eye on the sky’s dome. First find Jupiter and – presto – you’ve nearly stumbled upon Pluto. Just remember, Jupiter outshines Pluto by several million times.

Where are these worlds now? Both Pluto and Jupiter came out from behind the sun in January 2020, and then hovered low in the east before sunrise. Now – in June 2020 – these two worlds come up at late evening at mid-northern latitudes, and at mid-evening for the Southern Hemisphere. Jupiter and Pluto climb upward throughout the nighttime morning hours, to reach the meridian in the predawn/dawn sky on these June 2020 mornings.

Jupiter is very bright. You can’t miss it from late night until dawn on the nights of June 6 to 8, 2020. On June 8, the waning gibbous moon sweeps 1.3 degrees south of Pluto, and then – a few hours later – the moon swings 2.2 degrees south of Jupiter (at 17:19 UTC on June 8, 2020). Both Jupiter and Pluto are traveling in retrograde (westward) all month long, though Jupiter at a faster pace. Jupiter will catch up with Pluto on June 30, 2020, to stage the second of this year’s three Jupiter/Pluto conjunctions.

Of course, although Jupiter and Pluto nearly align along the same line of sight throughout 2020, these two worlds aren’t close together in space. Jupiter is a bit more than 5 astronomical units (AU) from the sun, while Pluto lodges way beyond Jupiter, in the Kuiper Belt, at about 34 AU from the sun. One astronomical unit (AU) = one sun/Earth distance.

Jupiter’s and Pluto’s present distance in AU via Heavens-Above

Here’s some observational data about Pluto for 2020, from In-the-Sky.org

Steven Bellavia in Mattituck, New York, captured Pluto on 2 separate nights, June 24 and June 27, 2019. In this animated gif, you can see that Pluto moved in front of the stars between those 2 nights. Steven wrote: “Most of the motion you see is actually from the Earth, not Pluto, since our motion changes our perspective of the much-closer Pluto against the backdrop of the much-farther stars.” Thanks, Steven!

Two planets are said to be in conjunction whenever they reside north and south of one another on the sky’s dome. Conjunctions of Jupiter and Pluto recur in periods of 12 to 13 years. The previous Jupiter-Pluto conjunction happened on December 11, 2007, and the one before that on December 2, 1994. After 2020, the next Jupiter-Pluto conjunction will occur on February 4, 2033, and the one following that on April 12, 2045. But the gap between Jupiter and Pluto at each one of these conjunctions is quite far apart, and the conjunctions of 1994, 2007, and 2033 happen so close to the sun that even Jupiter is lost in the sun’s glare.

Far and away, 2020 presents the best alignment of Jupiter and Pluto in the 21st century (2001 to 2100). What’s more, Jupiter and Pluto stage three conjunctions this year, as Jupiter passes less than one degree north of Pluto at each conjunction on April 5, June 30 and November 12, 2020. (For reference, the moon’s angular diameter spans about 1/2 degree of sky.) All of these conjunctions in 2020 take place in front of the constellation Sagittarius, with Jupiter first passing Pluto on April 5 in prograde (going eastward in front of the backdrop stars), then sweeping past Pluto on June 30 in retrograde (going westward relative to the background stars), and then for the final Jupiter-Pluto conjunction on November 12 in prograde (eastward).

All three Jupiter-Saturn conjunctions on April 5, June 30 and November 12, 2020 take pace place in front of the constellation Sagittarius, not far from the 5th-magnitude star 56 Sagittarii. Constellation chart via International Astronomical Union (IAU).

Most of the time, a Jupiter-Pluto conjunction in any year is a solitary event, as Jupiter laps Pluto going eastward, and never looks back. Triple conjunctions of Jupiter and Pluto – which occur over a period of about 7.4 months – are rare because Jupiter has to first catch Pluto going prograde (eastward), then in retrograde (westward) and then in prograde (eastward) again. The three-peat performance last happened in 1955-56 (November 2, 1955; February 8 and June 16, 1956), and will next occur in 2106-07 (July 13 and November 2, 2106; February 19, 2107). Yet, all three conjunctions in 1955-56 were widely spaced, and all three conjunctions in 2106-07 will be widely spaced, too.

Illustration showing why a superior planet appears to go in retrograde (westward in front of the backdrop stars of the zodiac). As seen from the north side of the solar system, all the planets orbit counter-clockwise. When the faster-moving Earth goes by a slower-moving superior planet, that planet appears to go backward (in retrograde). In 2020, Mars is in retrograde from September 9 to November 15, Jupiter from May 14 to September 13, and Saturn from May 11 to September 29. Image via Wikimedia Commons.

In other words, as we said above, 2020 may well showcase the best Jupiter-Pluto alignment for centuries to come. Most excitingly, both Jupiter and Pluto will reach opposition in mid-July 2020. At opposition, a superior planet – any planet revolving around the sun outside of Earth’s orbit – resides opposite the sun in Earth’s sky.

Opposition happens when Earth flies between a superior planet, like Mars, and the sun. This happens yearly for most of the outer planets (and every other year for Mars). Illustration via Heavens-Above.

At opposition, a superior planet (or superior dwarf planet) rises at sunset and sets at sunrise, and is out all night long. It’s at opposition that a planet shines at its brightest best in Earth’s sky, and it’s at or near opposition that a planet comes closest to Earth for the year.

Jupiter reaches opposition on July 14, 2020, at about 8:00 UTC, and comes closest to Earth on July 15, 2020, at about 10:00 UTC.

Pluto reaches opposition on July 15, 2020, at about 19:00 UTC, and comes closest to Earth on July 13, 2020, at about 9:00 UTC.

In an uncanny bit of timing, the oppositions of Jupiter and Pluto happen almost concurrently in mid-July 2020. A planet reaches opposition midway through a retrograde. However, since Pluto resides so much farther from the sun than Jupiter does, Pluto’s retrograde lasts nearly 1 1/2 months (six weeks) longer than Jupiter’s four-month retrograde. So for near-unison oppositions, Pluto’s retrograde has to start – and end – approximately three weeks before – and after – Jupiter’s retrograde.

Jupiter and Pluto retrograde/opposition in 2020

Jupiter begins retrograde: May 14, 2020, in front of the constellation Sagittarius
Jupiter at opposition: July 14, 2020, in front of the constellation Sagittarius
Jupiter ends retrograde: September 13, 2020, in front of the constellation Sagittarius

Pluto begins retrograde: April 25, 2020, in front of the constellation Sagittarius
Pluto at opposition: July 15, 2020, in front of the constellation Sagittarius
Pluto ends retrograde: October 4, 2020, in front of the constellation Sagittarius

Jupiter-Pluto conjunction tables via Richard Nolle

Call it serendipity or synergy – or whatever – but the spectacular alignment of the king planet Jupiter with the dwarf planet Pluto doesn’t get much better than in 2020. A similarly good Jupiter-Pluto rendezvous might not happen again for a number of centuries to come.

Pluto as seen with a 12″ S/C telescope (14.3 mag.) on July 10, 2015. Photo by Efrain Morales of Sociedad de Astronomia del Caribe. More information about Pluto’s current location.

Bottom line: Jupiter is as easy to find as the dwarf planet Pluto is difficult. Jupiter is bright! It ranks as the fourth-brightest celestial object to light up the heavens, after the sun, moon and Venus. Pluto, on the other hand, is 1,600 times dimmer than the faintest star visible to the unaided eye. But Jupiter can help you find – or at least envision – Pluto this year. That’s because these two worlds are having a triple conjunction this year; they’re near each other on the sky’s dome all year and will come exceptionally close 3 times in 2020.

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Mosaic image of Pluto and its largest moon Charon, captured around the time the New Horizons spacecraft swept closest to them on July 14, 2015. Image via NASA/ JHUAPL/ SwRI.

The year 2020 is exceptional for Jupiter and Pluto. These two worlds are having a triple conjunction this year. They’ll come together, move apart, and come together again three times in 2020. The first conjunction took place on April 5. The second one will come on June 30, and the final one on November 12. Because all of these Jupiter-Pluto conjunctions happen when these two planets are actually visible in our night sky (as opposed to being lost in the sun’s glare), this year’s Jupiter-Pluto alignment may be the best for centuries to come.

This year, very bright Jupiter and very faint Pluto will remain near each other throughout the year, closely aligned in front of the constellation Sagittarius. Pluto requires a telescope to be seen. No telescope? Try NASA’s Night Sky Network to find star parties and/or astronomy clubs near you.

And you don’t need a telescope to use your imagination. Throughout 2020, dazzling Jupiter will enable us to envision Pluto with the mind’s eye on the sky’s dome. First find Jupiter and – presto – you’ve nearly stumbled upon Pluto. Just remember, Jupiter outshines Pluto by several million times.

Where are these worlds now? Both Pluto and Jupiter came out from behind the sun in January 2020, and then hovered low in the east before sunrise. Now – in June 2020 – these two worlds come up at late evening at mid-northern latitudes, and at mid-evening for the Southern Hemisphere. Jupiter and Pluto climb upward throughout the nighttime morning hours, to reach the meridian in the predawn/dawn sky on these June 2020 mornings.

Jupiter is very bright. You can’t miss it from late night until dawn on the nights of June 6 to 8, 2020. On June 8, the waning gibbous moon sweeps 1.3 degrees south of Pluto, and then – a few hours later – the moon swings 2.2 degrees south of Jupiter (at 17:19 UTC on June 8, 2020). Both Jupiter and Pluto are traveling in retrograde (westward) all month long, though Jupiter at a faster pace. Jupiter will catch up with Pluto on June 30, 2020, to stage the second of this year’s three Jupiter/Pluto conjunctions.

Of course, although Jupiter and Pluto nearly align along the same line of sight throughout 2020, these two worlds aren’t close together in space. Jupiter is a bit more than 5 astronomical units (AU) from the sun, while Pluto lodges way beyond Jupiter, in the Kuiper Belt, at about 34 AU from the sun. One astronomical unit (AU) = one sun/Earth distance.

Jupiter’s and Pluto’s present distance in AU via Heavens-Above

Here’s some observational data about Pluto for 2020, from In-the-Sky.org

Steven Bellavia in Mattituck, New York, captured Pluto on 2 separate nights, June 24 and June 27, 2019. In this animated gif, you can see that Pluto moved in front of the stars between those 2 nights. Steven wrote: “Most of the motion you see is actually from the Earth, not Pluto, since our motion changes our perspective of the much-closer Pluto against the backdrop of the much-farther stars.” Thanks, Steven!

Two planets are said to be in conjunction whenever they reside north and south of one another on the sky’s dome. Conjunctions of Jupiter and Pluto recur in periods of 12 to 13 years. The previous Jupiter-Pluto conjunction happened on December 11, 2007, and the one before that on December 2, 1994. After 2020, the next Jupiter-Pluto conjunction will occur on February 4, 2033, and the one following that on April 12, 2045. But the gap between Jupiter and Pluto at each one of these conjunctions is quite far apart, and the conjunctions of 1994, 2007, and 2033 happen so close to the sun that even Jupiter is lost in the sun’s glare.

Far and away, 2020 presents the best alignment of Jupiter and Pluto in the 21st century (2001 to 2100). What’s more, Jupiter and Pluto stage three conjunctions this year, as Jupiter passes less than one degree north of Pluto at each conjunction on April 5, June 30 and November 12, 2020. (For reference, the moon’s angular diameter spans about 1/2 degree of sky.) All of these conjunctions in 2020 take place in front of the constellation Sagittarius, with Jupiter first passing Pluto on April 5 in prograde (going eastward in front of the backdrop stars), then sweeping past Pluto on June 30 in retrograde (going westward relative to the background stars), and then for the final Jupiter-Pluto conjunction on November 12 in prograde (eastward).

All three Jupiter-Saturn conjunctions on April 5, June 30 and November 12, 2020 take pace place in front of the constellation Sagittarius, not far from the 5th-magnitude star 56 Sagittarii. Constellation chart via International Astronomical Union (IAU).

Most of the time, a Jupiter-Pluto conjunction in any year is a solitary event, as Jupiter laps Pluto going eastward, and never looks back. Triple conjunctions of Jupiter and Pluto – which occur over a period of about 7.4 months – are rare because Jupiter has to first catch Pluto going prograde (eastward), then in retrograde (westward) and then in prograde (eastward) again. The three-peat performance last happened in 1955-56 (November 2, 1955; February 8 and June 16, 1956), and will next occur in 2106-07 (July 13 and November 2, 2106; February 19, 2107). Yet, all three conjunctions in 1955-56 were widely spaced, and all three conjunctions in 2106-07 will be widely spaced, too.

Illustration showing why a superior planet appears to go in retrograde (westward in front of the backdrop stars of the zodiac). As seen from the north side of the solar system, all the planets orbit counter-clockwise. When the faster-moving Earth goes by a slower-moving superior planet, that planet appears to go backward (in retrograde). In 2020, Mars is in retrograde from September 9 to November 15, Jupiter from May 14 to September 13, and Saturn from May 11 to September 29. Image via Wikimedia Commons.

In other words, as we said above, 2020 may well showcase the best Jupiter-Pluto alignment for centuries to come. Most excitingly, both Jupiter and Pluto will reach opposition in mid-July 2020. At opposition, a superior planet – any planet revolving around the sun outside of Earth’s orbit – resides opposite the sun in Earth’s sky.

Opposition happens when Earth flies between a superior planet, like Mars, and the sun. This happens yearly for most of the outer planets (and every other year for Mars). Illustration via Heavens-Above.

At opposition, a superior planet (or superior dwarf planet) rises at sunset and sets at sunrise, and is out all night long. It’s at opposition that a planet shines at its brightest best in Earth’s sky, and it’s at or near opposition that a planet comes closest to Earth for the year.

Jupiter reaches opposition on July 14, 2020, at about 8:00 UTC, and comes closest to Earth on July 15, 2020, at about 10:00 UTC.

Pluto reaches opposition on July 15, 2020, at about 19:00 UTC, and comes closest to Earth on July 13, 2020, at about 9:00 UTC.

In an uncanny bit of timing, the oppositions of Jupiter and Pluto happen almost concurrently in mid-July 2020. A planet reaches opposition midway through a retrograde. However, since Pluto resides so much farther from the sun than Jupiter does, Pluto’s retrograde lasts nearly 1 1/2 months (six weeks) longer than Jupiter’s four-month retrograde. So for near-unison oppositions, Pluto’s retrograde has to start – and end – approximately three weeks before – and after – Jupiter’s retrograde.

Jupiter and Pluto retrograde/opposition in 2020

Jupiter begins retrograde: May 14, 2020, in front of the constellation Sagittarius
Jupiter at opposition: July 14, 2020, in front of the constellation Sagittarius
Jupiter ends retrograde: September 13, 2020, in front of the constellation Sagittarius

Pluto begins retrograde: April 25, 2020, in front of the constellation Sagittarius
Pluto at opposition: July 15, 2020, in front of the constellation Sagittarius
Pluto ends retrograde: October 4, 2020, in front of the constellation Sagittarius

Jupiter-Pluto conjunction tables via Richard Nolle

Call it serendipity or synergy – or whatever – but the spectacular alignment of the king planet Jupiter with the dwarf planet Pluto doesn’t get much better than in 2020. A similarly good Jupiter-Pluto rendezvous might not happen again for a number of centuries to come.

Pluto as seen with a 12″ S/C telescope (14.3 mag.) on July 10, 2015. Photo by Efrain Morales of Sociedad de Astronomia del Caribe. More information about Pluto’s current location.

Bottom line: Jupiter is as easy to find as the dwarf planet Pluto is difficult. Jupiter is bright! It ranks as the fourth-brightest celestial object to light up the heavens, after the sun, moon and Venus. Pluto, on the other hand, is 1,600 times dimmer than the faintest star visible to the unaided eye. But Jupiter can help you find – or at least envision – Pluto this year. That’s because these two worlds are having a triple conjunction this year; they’re near each other on the sky’s dome all year and will come exceptionally close 3 times in 2020.

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Want to see Saturn’s rings? Read me 1st

James Martin in Albuquerque, New Mexico, caught this photo of Saturn at its 2017 opposition, when the rings were maximally tilted toward Earth. Opposition marks the middle of the best time of year to see an outer planet. The 2020 opposition will happen on July 20.

It’s that magical time of year again, when our solar system’s most beautiful planet – Saturn – is becoming well placed for viewing in our sky. Saturn looks starlike to the eye alone, but it shines steadily, as planets tend to do, and it has a distinct golden color. So Saturn is a lovely object to view with the eye alone. Binoculars will enhance its color, and even small telescopes will show you Saturn’s rings. Veteran observer Alan MacRobert at SkyandTelescope.com has written:

The rings of Saturn should be visible in even the smallest telescope at 25x [magnified by 25 times]. A good 3-inch scope at 50x [magnified by 50 times] can show them as a separate structure detached on all sides from the ball of the planet.

You want to see Saturn’s rings. We know you do! With the moon passing Saturn this week, it’s a good time to identify the planet with the eye alone. See the chart below:

The moon sweeps past Saturn on the nights of June 7 and 8, 2020. Read more.

See, on the chart above, how Saturn is near a brighter planet, Jupiter? These two planets will be near each other throughout 2020. Jupiter outshines all the stars, so its proximity to Saturn will make finding Saturn a breeze. And, before this year ends, Jupiter and Saturn will have a great conjunction?

Okay, got Saturn? It’ll be great fun to watch it and Jupiter throughout the rest of 2020. Now … about that telescope. One possibility is to start scouting out a star party near you, where amateur astronomers are set up to show you telescopic objects. Check the club map at NASA’s Night Sky Network to find star parties. Or try this list of astronomy clubs by state from the Astronomical League. Or call a local university or science museum and ask about star parties. Or maybe a neighbor, or friend, has a telescope stashed in a closet? More possibilities:

Astronomy Clubs Near Me & Organizations, from SkyandTelescope.com.

2018 Astronomy Club Directory, from Go-Astronomy.com.

Astronomy Clubs Near Me, from LoveTheNightSky.com.

Okay, so you can find Saturn in the sky, and you’ve found a star party to attend. Here are some things to think about before your Saturn ring-viewing session:

1. Telescope. Don’t expect to see the rings in binoculars. You really do need a telescope. A bigger telescope will show you more than a smaller telescope. Check out the contrast between the two photos below.

These images suggest how the ringed planet Saturn might look when seen through a telescope with an aperture 4 inches (100 mm) in diameter (top) and through a larger instrument with an 8-inch (200 mm) aperture (bottom). Image via SkyandTelescope.com/ NASA/ Hubble Space Telescope.

2. Tilt. Notice the tilt of the rings. As with so much in space (and on Earth), the appearance of Saturn’s rings from Earth is cyclical. In 2017, the north side of the rings opened up most widely (27 degrees), as seen from Earth. That’s the most open this face of the rings has been since since 1988. In 2020, we’re past the peak of the north ring face opening, but Saturn’s rings are still inclined at nearly 22 degrees from edge-on, still exhibiting their northern face. By the year 2025, the rings will appear edge-on as seen from Earth. At such times, because the rings are so thin, it’s possible to view Saturn through a telescope as if it has no rings at all! After that, we’ll begin to see the south side of Saturn’s rings and their openness will gradually increase to a maximum inclination of 27 degrees by May 2032.

The tilt of Saturn’s rings has a great impact on the planet’s overall brightness as seen from Earth. In years when Saturn’s rings are edge-on as seen from Earth (2009 and 2025), Saturn does appear considerably dimmer than in years when Saturn’s rings are maximally tilted toward Earth (2017 and 2032). These Saturn views were simulated with a computer program written by Tom Ruen. Image via Wikimedia Commons.

3. 3D. Ask yourself … do Saturn’s rings look three-dimensional? Again quoting Alan MacRobert at SkyandTelescope.com:

Saturn has a more three-dimensional appearance than any other object in the sky — at least that’s how it looks to me with a 6-inch ‘scope on a night of fine seeing.

4. Seeing. What was Alan talking about in that quote above when he mentioned seeing? Both amateur and professional astronomers talk about the night’s seeing, which affects how clearly and sharply you can see a telescopic image. Seeing isn’t a quality of the telescope; it’s a quality of the air above you. It’s the reason the stars twinkle more on some nights than others. When the air is particularly turbulent, astronomers say there’s bad seeing. The images at the telescope shimmy and dance. When the air is particularly still, astronomers say there’s good seeing. Seeing can shift from moment to moment, as parcels of air move above you. So, as you’re gazing at Saturn, stand as quietly as you can – for as long as you can – and just look. You’ll notice moments when the image suddenly comes into sharper focus.

Turbulent air makes for poor seeing. But the air above you can also “settle” suddenly. When viewing Saturn, wait for those moments. Image via AstronomyNotes.com.

5. Other things to think about. Once you get comfortable viewing Saturn – assuming you’re able to view it again and again, with a telescope of your own – you’ll begin to notice details in the rings. Today, thanks to spacecraft, we know that Saturn’s rings are incredibly detailed. But, as you stand at your telescope gazing upward, you might be thrilled to witness just one primary division in the rings, the Cassini Division between the A and B rings, named for its French discoverer Jean Cassini. Seeing this dark division is a good test of the night’s seeing and your telescope’s optical quality, and also of your own eyes’ ability to simply look and notice what you see. By the way, if you’re looking at the rings – which means you’re viewing Saturn through a telescope – look also for one or more of Saturn’s many moons, most notably Titan.

Have fun!

Alas, you won’t see Saturn look like this through a telescope. This is a spacecraft view, from Cassini in 2016, showing Saturn’s northern hemisphere. Image via NASA/ JPL-Caltech/ Space Science Institute.

Bottom line: In 2020, Saturn’s opposition – marking the middle of the best time of year to see it – comes on July 20. Here are some tips for beginners who want to see Saturn’s rings.

Read more … Viewing Saturn: Rings, Planet and Moons

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from EarthSky https://ift.tt/2Y9hEUV

James Martin in Albuquerque, New Mexico, caught this photo of Saturn at its 2017 opposition, when the rings were maximally tilted toward Earth. Opposition marks the middle of the best time of year to see an outer planet. The 2020 opposition will happen on July 20.

It’s that magical time of year again, when our solar system’s most beautiful planet – Saturn – is becoming well placed for viewing in our sky. Saturn looks starlike to the eye alone, but it shines steadily, as planets tend to do, and it has a distinct golden color. So Saturn is a lovely object to view with the eye alone. Binoculars will enhance its color, and even small telescopes will show you Saturn’s rings. Veteran observer Alan MacRobert at SkyandTelescope.com has written:

The rings of Saturn should be visible in even the smallest telescope at 25x [magnified by 25 times]. A good 3-inch scope at 50x [magnified by 50 times] can show them as a separate structure detached on all sides from the ball of the planet.

You want to see Saturn’s rings. We know you do! With the moon passing Saturn this week, it’s a good time to identify the planet with the eye alone. See the chart below:

The moon sweeps past Saturn on the nights of June 7 and 8, 2020. Read more.

See, on the chart above, how Saturn is near a brighter planet, Jupiter? These two planets will be near each other throughout 2020. Jupiter outshines all the stars, so its proximity to Saturn will make finding Saturn a breeze. And, before this year ends, Jupiter and Saturn will have a great conjunction?

Okay, got Saturn? It’ll be great fun to watch it and Jupiter throughout the rest of 2020. Now … about that telescope. One possibility is to start scouting out a star party near you, where amateur astronomers are set up to show you telescopic objects. Check the club map at NASA’s Night Sky Network to find star parties. Or try this list of astronomy clubs by state from the Astronomical League. Or call a local university or science museum and ask about star parties. Or maybe a neighbor, or friend, has a telescope stashed in a closet? More possibilities:

Astronomy Clubs Near Me & Organizations, from SkyandTelescope.com.

2018 Astronomy Club Directory, from Go-Astronomy.com.

Astronomy Clubs Near Me, from LoveTheNightSky.com.

Okay, so you can find Saturn in the sky, and you’ve found a star party to attend. Here are some things to think about before your Saturn ring-viewing session:

1. Telescope. Don’t expect to see the rings in binoculars. You really do need a telescope. A bigger telescope will show you more than a smaller telescope. Check out the contrast between the two photos below.

These images suggest how the ringed planet Saturn might look when seen through a telescope with an aperture 4 inches (100 mm) in diameter (top) and through a larger instrument with an 8-inch (200 mm) aperture (bottom). Image via SkyandTelescope.com/ NASA/ Hubble Space Telescope.

2. Tilt. Notice the tilt of the rings. As with so much in space (and on Earth), the appearance of Saturn’s rings from Earth is cyclical. In 2017, the north side of the rings opened up most widely (27 degrees), as seen from Earth. That’s the most open this face of the rings has been since since 1988. In 2020, we’re past the peak of the north ring face opening, but Saturn’s rings are still inclined at nearly 22 degrees from edge-on, still exhibiting their northern face. By the year 2025, the rings will appear edge-on as seen from Earth. At such times, because the rings are so thin, it’s possible to view Saturn through a telescope as if it has no rings at all! After that, we’ll begin to see the south side of Saturn’s rings and their openness will gradually increase to a maximum inclination of 27 degrees by May 2032.

The tilt of Saturn’s rings has a great impact on the planet’s overall brightness as seen from Earth. In years when Saturn’s rings are edge-on as seen from Earth (2009 and 2025), Saturn does appear considerably dimmer than in years when Saturn’s rings are maximally tilted toward Earth (2017 and 2032). These Saturn views were simulated with a computer program written by Tom Ruen. Image via Wikimedia Commons.

3. 3D. Ask yourself … do Saturn’s rings look three-dimensional? Again quoting Alan MacRobert at SkyandTelescope.com:

Saturn has a more three-dimensional appearance than any other object in the sky — at least that’s how it looks to me with a 6-inch ‘scope on a night of fine seeing.

4. Seeing. What was Alan talking about in that quote above when he mentioned seeing? Both amateur and professional astronomers talk about the night’s seeing, which affects how clearly and sharply you can see a telescopic image. Seeing isn’t a quality of the telescope; it’s a quality of the air above you. It’s the reason the stars twinkle more on some nights than others. When the air is particularly turbulent, astronomers say there’s bad seeing. The images at the telescope shimmy and dance. When the air is particularly still, astronomers say there’s good seeing. Seeing can shift from moment to moment, as parcels of air move above you. So, as you’re gazing at Saturn, stand as quietly as you can – for as long as you can – and just look. You’ll notice moments when the image suddenly comes into sharper focus.

Turbulent air makes for poor seeing. But the air above you can also “settle” suddenly. When viewing Saturn, wait for those moments. Image via AstronomyNotes.com.

5. Other things to think about. Once you get comfortable viewing Saturn – assuming you’re able to view it again and again, with a telescope of your own – you’ll begin to notice details in the rings. Today, thanks to spacecraft, we know that Saturn’s rings are incredibly detailed. But, as you stand at your telescope gazing upward, you might be thrilled to witness just one primary division in the rings, the Cassini Division between the A and B rings, named for its French discoverer Jean Cassini. Seeing this dark division is a good test of the night’s seeing and your telescope’s optical quality, and also of your own eyes’ ability to simply look and notice what you see. By the way, if you’re looking at the rings – which means you’re viewing Saturn through a telescope – look also for one or more of Saturn’s many moons, most notably Titan.

Have fun!

Alas, you won’t see Saturn look like this through a telescope. This is a spacecraft view, from Cassini in 2016, showing Saturn’s northern hemisphere. Image via NASA/ JPL-Caltech/ Space Science Institute.

Bottom line: In 2020, Saturn’s opposition – marking the middle of the best time of year to see it – comes on July 20. Here are some tips for beginners who want to see Saturn’s rings.

Read more … Viewing Saturn: Rings, Planet and Moons

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