View at EarthSky Community Photos. | Closeup of Jupiter and Saturn, via Dr Ski. Saturn has been closely following Jupiter westward across the sky each night for most of 2020. The pair is bright in the evening sky in September. Although Saturn is easily as bright as a 1st-magnitude star, the ringed planet pales next the the king planet Jupiter, which outshines Saturn by some 15 times. Thank you, Dr Ski!
Astronomers use the word conjunction to describe meetings of planets and other objects on our sky’s dome. They use the term great conjunction to describe meetings of Jupiter and Saturn, the two biggest worlds in our solar system. The next great conjunction of Jupiter and Saturn will be December 21, 2020. It’ll be the first Jupiter-Saturn conjunction since the year 2000, and the closest Jupiter-Saturn conjunction since the year 1623! At their closest, Jupiter and Saturn will be only 0.1 degrees apart. That’s just 1/5 of a full moon diameter.
The extra-close Jupiter-Saturn conjunction in 2020 won’t be matched again until the Jupiter-Saturn conjunction of March 15, 2080.
The 2021 lunar calendars are here! Order yours before they’re gone. Makes a great gift!
But don’t wait until December to start watching these worlds. They’re visible tonight and every night – near each other for the rest of 2020 – an appealing and mind-expanding sight!
In late October and early November 2020, Jupiter and Saturn are very bright and noticeable in the sky when darkness falls. The moon will sweep past them from October 21 to 23. Read more.
At the 2000 great conjunction, Jupiter and Saturn were near the sun in our sky and difficult to observe. We’re due for a more observable great conjunction, and we’ll get one. In October and November, Jupiter and Saturn are noticeable for their nearness to each other, and in the sky when darkness falls. By December, Jupiter and Saturn will still be easily visible, in the west shortly after sunset.
You’ll recognize Jupiter and Saturn easily, from now through the end of the year. Jupiter is brighter than any star. Saturn is not as bright as Jupiter, but it’s as bright as the brightest stars and shines with a distinctly golden color. Also, Jupiter is near Saturn! Saturn is just to the east of Jupiter on the sky’s dome. Unlike the twinkling stars, Jupiter and Saturn both shine steadily.
When the moon sweeps past Jupiter and Saturn around October 21 to 23, 2020, the two planets will reside about 6 degrees apart on the sky’s dome. For reference, the moon’s angular diameter equals about 1/2 degree. This next month – from October 21 to November 21, 2020 – Jupiter will travel about 5 degrees on the sky’s dome, while Saturn will travel about 2 degrees in the sky. So Jupiter will gain 3 degrees on Saturn, and the two gas giant planets will be some 3 degrees apart as of November 21, 2020.
The following month – November 21 to December 21, 2020 – Jupiter will travel about 6 degrees and Saturn 3 degrees. That means Jupiter will have bridged the 3-degree gap that had existed between the king planet and Saturn on November 21, 2020!
Overall – from October 21 to December 21, 2020 – Jupiter will have traveled 11 degrees and Saturn 5 degrees. Bingo! That’ll completely close the 6-degree gap that separated Jupiter and Saturn on October 21, 2020!
View at EarthSky Community Photos. | Fredric Walder caught this photo of Jupiter and Saturn on September 14, 2020. He wrote: “Fall in the Northern Hemisphere presents the opportunity to see the Milky Way just after sunset. In this photo the famous Balanced Rock in Arches National Park, the planets Jupiter and Saturn, our Milky Way galaxy, and a bit of post-sunset zodiacal light are all visible. The sky takes on a red tone due to smoke in the atmosphere from fires on the West Coast.” Thank you, Fredric!
Saturn, the sixth planet outward from the sun, is the farthest and slowest-moving planet that we can easily see with the eye alone. Dazzling Jupiter, the fifth planet outward from the sun, is the second-slowest bright planet, after Saturn.
For that reason, Jupiter/Saturn conjunctions are the rarest of bright-planet conjunctions, by virtue of their slow motions in front of the constellations of the zodiac. Saturn takes nearly 30 years to go around the sun full circle whereas Jupiter takes nearly 12 years.
Thus, every 20 years, Jupiter catches up to Saturn as viewed from Earth.
From the years 2000 to 2100 inclusive, as viewed from our planet Earth, these Jupiter/Saturn conjunctions (in ecliptic longitude) happen on these dates:
May 28, 2000
December 21, 2020
October 31, 2040
April 7, 2060
March 15, 2080
September 18, 2100
Artist’s concept of Jupiter and Saturn in December of 2020, as viewed from a space-based perspective. Their conjunction will be December 21. See the moon in this drawing? It’ll be along our line of sight to the planets on December 16, 2020. Chart via Jay Ryan at ClassicalAstronomy.com.
Now, here’s why these great Jupiter/Saturn conjunctions happen every 20 years. Each year, Saturn completes about 12 degrees of its orbit around the sun, whereas Jupiter completes about 30 degrees. Therefore, in one year, Jupiter closes the gap between itself and Saturn by about 18 degrees (30 – 12 = 18 degrees).
In a period of 20 years, then, Jupiter gains 360 degrees on Saturn (18 x 20 = 360 degrees), therefore lapping the ringed planet once every 20 years.
So start watching Jupiter and Saturn now! And mark your calendar for the great conjunction of Jupiter and Saturn on December 21, 2020.
View at EarthSky Community Photos. | As you gaze toward Jupiter and Saturn in the night sky, imagine a 3rd planet near them, invisible to the eye and even to some small telescopes. Joel Weatherly of Edmonton, Aberta, Canada, captured this image. He wrote, “Autumn’s lengthening nights offer an excellent opportunity to explore the sky before it gets too cold. Planets such as Jupiter and Saturn have been highlights of the night, but the accompanying starfield is worth a gander as well. Pluto isn’t visible in this image, but that’s where it was hanging out.” Thank you, Joel! Read more about the triple conjunction of Jupiter and Pluto in 2020.
Bottom line: The next great conjunction of Jupiter and Saturn will be December 21, 2020. It’ll be the first Jupiter-Saturn conjunction since the year 2000, and the closest Jupiter-Saturn conjunction since the year 1623! At their closest, Jupiter and Saturn will be only 0.1 degrees apart. That’s just 1/5 of a full moon diameter. Charts and more info here.
from EarthSky https://ift.tt/2WVmFCm
View at EarthSky Community Photos. | Closeup of Jupiter and Saturn, via Dr Ski. Saturn has been closely following Jupiter westward across the sky each night for most of 2020. The pair is bright in the evening sky in September. Although Saturn is easily as bright as a 1st-magnitude star, the ringed planet pales next the the king planet Jupiter, which outshines Saturn by some 15 times. Thank you, Dr Ski!
Astronomers use the word conjunction to describe meetings of planets and other objects on our sky’s dome. They use the term great conjunction to describe meetings of Jupiter and Saturn, the two biggest worlds in our solar system. The next great conjunction of Jupiter and Saturn will be December 21, 2020. It’ll be the first Jupiter-Saturn conjunction since the year 2000, and the closest Jupiter-Saturn conjunction since the year 1623! At their closest, Jupiter and Saturn will be only 0.1 degrees apart. That’s just 1/5 of a full moon diameter.
The extra-close Jupiter-Saturn conjunction in 2020 won’t be matched again until the Jupiter-Saturn conjunction of March 15, 2080.
The 2021 lunar calendars are here! Order yours before they’re gone. Makes a great gift!
But don’t wait until December to start watching these worlds. They’re visible tonight and every night – near each other for the rest of 2020 – an appealing and mind-expanding sight!
In late October and early November 2020, Jupiter and Saturn are very bright and noticeable in the sky when darkness falls. The moon will sweep past them from October 21 to 23. Read more.
At the 2000 great conjunction, Jupiter and Saturn were near the sun in our sky and difficult to observe. We’re due for a more observable great conjunction, and we’ll get one. In October and November, Jupiter and Saturn are noticeable for their nearness to each other, and in the sky when darkness falls. By December, Jupiter and Saturn will still be easily visible, in the west shortly after sunset.
You’ll recognize Jupiter and Saturn easily, from now through the end of the year. Jupiter is brighter than any star. Saturn is not as bright as Jupiter, but it’s as bright as the brightest stars and shines with a distinctly golden color. Also, Jupiter is near Saturn! Saturn is just to the east of Jupiter on the sky’s dome. Unlike the twinkling stars, Jupiter and Saturn both shine steadily.
When the moon sweeps past Jupiter and Saturn around October 21 to 23, 2020, the two planets will reside about 6 degrees apart on the sky’s dome. For reference, the moon’s angular diameter equals about 1/2 degree. This next month – from October 21 to November 21, 2020 – Jupiter will travel about 5 degrees on the sky’s dome, while Saturn will travel about 2 degrees in the sky. So Jupiter will gain 3 degrees on Saturn, and the two gas giant planets will be some 3 degrees apart as of November 21, 2020.
The following month – November 21 to December 21, 2020 – Jupiter will travel about 6 degrees and Saturn 3 degrees. That means Jupiter will have bridged the 3-degree gap that had existed between the king planet and Saturn on November 21, 2020!
Overall – from October 21 to December 21, 2020 – Jupiter will have traveled 11 degrees and Saturn 5 degrees. Bingo! That’ll completely close the 6-degree gap that separated Jupiter and Saturn on October 21, 2020!
View at EarthSky Community Photos. | Fredric Walder caught this photo of Jupiter and Saturn on September 14, 2020. He wrote: “Fall in the Northern Hemisphere presents the opportunity to see the Milky Way just after sunset. In this photo the famous Balanced Rock in Arches National Park, the planets Jupiter and Saturn, our Milky Way galaxy, and a bit of post-sunset zodiacal light are all visible. The sky takes on a red tone due to smoke in the atmosphere from fires on the West Coast.” Thank you, Fredric!
Saturn, the sixth planet outward from the sun, is the farthest and slowest-moving planet that we can easily see with the eye alone. Dazzling Jupiter, the fifth planet outward from the sun, is the second-slowest bright planet, after Saturn.
For that reason, Jupiter/Saturn conjunctions are the rarest of bright-planet conjunctions, by virtue of their slow motions in front of the constellations of the zodiac. Saturn takes nearly 30 years to go around the sun full circle whereas Jupiter takes nearly 12 years.
Thus, every 20 years, Jupiter catches up to Saturn as viewed from Earth.
From the years 2000 to 2100 inclusive, as viewed from our planet Earth, these Jupiter/Saturn conjunctions (in ecliptic longitude) happen on these dates:
May 28, 2000
December 21, 2020
October 31, 2040
April 7, 2060
March 15, 2080
September 18, 2100
Artist’s concept of Jupiter and Saturn in December of 2020, as viewed from a space-based perspective. Their conjunction will be December 21. See the moon in this drawing? It’ll be along our line of sight to the planets on December 16, 2020. Chart via Jay Ryan at ClassicalAstronomy.com.
Now, here’s why these great Jupiter/Saturn conjunctions happen every 20 years. Each year, Saturn completes about 12 degrees of its orbit around the sun, whereas Jupiter completes about 30 degrees. Therefore, in one year, Jupiter closes the gap between itself and Saturn by about 18 degrees (30 – 12 = 18 degrees).
In a period of 20 years, then, Jupiter gains 360 degrees on Saturn (18 x 20 = 360 degrees), therefore lapping the ringed planet once every 20 years.
So start watching Jupiter and Saturn now! And mark your calendar for the great conjunction of Jupiter and Saturn on December 21, 2020.
View at EarthSky Community Photos. | As you gaze toward Jupiter and Saturn in the night sky, imagine a 3rd planet near them, invisible to the eye and even to some small telescopes. Joel Weatherly of Edmonton, Aberta, Canada, captured this image. He wrote, “Autumn’s lengthening nights offer an excellent opportunity to explore the sky before it gets too cold. Planets such as Jupiter and Saturn have been highlights of the night, but the accompanying starfield is worth a gander as well. Pluto isn’t visible in this image, but that’s where it was hanging out.” Thank you, Joel! Read more about the triple conjunction of Jupiter and Pluto in 2020.
Bottom line: The next great conjunction of Jupiter and Saturn will be December 21, 2020. It’ll be the first Jupiter-Saturn conjunction since the year 2000, and the closest Jupiter-Saturn conjunction since the year 1623! At their closest, Jupiter and Saturn will be only 0.1 degrees apart. That’s just 1/5 of a full moon diameter. Charts and more info here.
from EarthSky https://ift.tt/2WVmFCm
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