8 ms·

The Dec 21, 2020 Conjunction of Jupiter and Saturn

143 points by chmaynard 6y ago

ggambetta 6y ago
According to ancient scripture, "when the three planets are in eclipse, a black hole like a door is open, evil comes, spreading terror and chaos". The archaeologist working on this back in 1914 estimated this would happen every five thousand years (if his assumptions for the signs representing "1" and "5" were correct). Fortunately, this isn't expected to happen until 2263. Still, in a 2020 full of surprises, having alignment of two out of three planets is too close for comfort. (just to make this perfectly green: no, this comment is not supposed to be taken seriously)
- jrootabega 6y ago
  Aziz light?
  - ggambetta 6y ago
    Much better, thank you, Aziz. Aziz looks confused
  - gruturo 6y ago
    AZIZ! LIGHT!
    - lifeisstillgood 6y ago
      oooohhh - OK now I get it ... thank you (spoiler - opening scene of the fifth element)
- friendlybus 6y ago
  Crystal green? Any kind of green
- mcintyre1994 6y ago
  Perhaps the Mayans were exactly 8 years out? :)
- thebigspacefuck 6y ago
  Three in alignment is called a syzygy. Apparently this occurrence in the house of Aquarius is particularly bad. There’s an X-Files about it.
- dane-pgp 6y ago
  Slightly more seriously, it's interesting to note that, according to Wikipedia[0]: > When studying the great conjunction of 1603, Johannes Kepler thought that the Star of Bethlehem might have been the occurrence of a great conjunction. ... A triple conjunction is a conjunction of Jupiter and Saturn at or near their opposition to the Sun. In this scenario, Jupiter and Saturn will occupy the same position in right ascension (or ecliptic longitude) on three occasions (due to apparent retrograde motion) over a period of a few months. Presumably the significance of a triple conjunction is that it explains the story of the Magi seeing a "star in the East", which then "troubled" Jerusalem when they arrived there, until it "went before them", and then finally "stood over where the young Child was".[1] [0] https://en.wikipedia.org/wiki/Great_conjunction#%E2%88%926 https://en.wikipedia.org/wiki/Great_conjunction#%E2%88%926 [1] https://www.biblegateway.com/passage/?search=Matthew+2%3A1-12&version=NKJV https://www.biblegateway.com/passage/?search=Matthew+2%3A1-1...
  - antognini 6y ago
    In addition to that, while Kepler was lecturing on the Great Conjunction he was drawing the trigon [1] which shows how the locations of Great Conjunctions change over time. This drawing (consisting of a triangle inscribed inside a circle that gets shifted over time), inspired him to pursue the idea that the distances to the planets were determined by polygons of different shapes inscribed in circles. This didn't work, so he moved on to Platonic solids, which worked better, but still not perfectly. Eventually this pursuit lead him to the idea of describing the planetary orbits by ellipses. [1]: https://en.wikipedia.org/wiki/Great_conjunction#/media/File:Keplers_trigon.jpg https://en.wikipedia.org/wiki/Great_conjunction#/media/File:...
deleted 6y ago
[deleted]
piker 6y ago
Not clear from the article if this is worth the effort of purchasing/setting up a telescope from rural SW England, but if any astronomers on can interpret how likely it would be to be visible under perfect conditions that would be really appreciated. Viewing this could be a great experience for a family over Christmas during the brief UK lockdown reprieve.
- jankotek 6y ago
  You need very good location with unobstructed view over western horizont. Some preparation and a bit of luck with weather. It is not a rocket science. But get telescope in any case. Even cheap stuff from Lidl will show some details on saturn rings and cloud belts on jupiter. And there is also Moon and stars..
  - lifeisstillgood 6y ago
    Do you have any good (ie busy father orientated) instructions on buying and setting up a basic telescope ?
    - bartman 6y ago
      Take a look at https://skyandtelescope.org/wp-content/uploads/3-scopes.pdf https://skyandtelescope.org/wp-content/uploads/3-scopes.pdf for a good overview of 3 typical entry level suggestions. I have the Onesky (or rather it’s European sibling the Heritage 130P) and enjoy it. It doesn’t have any fancy features, but is easy to move around, doesn’t take up much storage space and still has plenty of power! If you’re willing to spend some more, the Celestron NexStar 5 and 6 are solid telescopes that can automatically move to specific objects in the sky (this is called GoTo) which is really nice if you want to focus more on viewing objects rather than finding them. They’re low on maintenance too and work well for showing others objects in the sky as they can keep whatever you look at centered in the eyepiece.
    - jankotek 6y ago
      binoculars on tripod, if youwant planets then 7cm basic refractor
thomc 6y ago
My wife gave me my Christmas present (a telescope) a little early this year so that I could practice and hopefully be ready for this event. I've had a few sessions already and it feels really special out in the cold night looking up at Mars and other planets whiz by. It does need some preparation though. I've got my site on a hill selected with no obstructions, the telescope has been collimated (calibrated), red dot finder is alligned, I've learnt how to setup the equatorial mount and polar align it, and I have my blue filter for clearer visuals of Saturn and Jupiter. Meanwhile I'm out in the back garden checking for clear skies any chance I get. One thing to know though, you won't see the planets as they often appear in pictures, those are usually made from hundreds of long exposure shots stacked and processed to bring out the detail. You pretty much just see small bright spots in the sky with a little surface detail if your optics are good enough. There is something about seeing far away planets with your own eyes however which feels magic and photos can't compare to the experience.
- bamboozled 6y ago
  I’ve lived almost this exact experience during winter after borrowing a telescope from a close relative. I could make out the rings of Saturn from my backyard and it was a special type of magic, an unforgettable experience the first time it happened.
  - wdfx 6y ago
    I bought myself my first scope this summer and have been watching both Saturn, juipter and now mars on occasion as they've precessed across the evening sky. Same feelings for me, it's magical to observe first hand with analogue optics and eyeball these planets :)
- sizzzzlerz 6y ago
  Sounds like you've made a good start, if you're a first time scope owner. Even a modest telescope can provide you views of the solar system as well as deep sky objects that can take your breath away. If I could, a couple suggestions that can enhance your enjoyment of your scope as you become familiar with it and the sky. First, keep a log of each viewing session. Note time and date, location, sky conditions, what you viewed. If you're so inclined, make sketches of what you see. Its nice, later on, to have a record of what you've look at and how it may have changed when you go back to it. Second, find a local astronomy club you feel comfortable with. Most people will go out of their way to help a newbie. Attend any star parties that they may hold. They're great ways to see how others work and to see what other types of scopes can do. You will also learn how to better use what you have. In any case, enjoy your scope. They can be great fun and they really bring home how wonderous the skies are.
mellosouls 6y ago
Another nice summary here courtesy of the Beeb (more of a UK focus): https://www.skyatnightmagazine.com/advice/skills/great-conjunction-jupiter-saturn/ https://www.skyatnightmagazine.com/advice/skills/great-conju...
gandalfian 6y ago
I have been watching the bright blob of Jupiter (UK) this winter and assumed that to the naked eye Saturn was just merged in there too close to seperate. Is this right or was one of the near by stars actually Saturn and I didn't realize? Thanks
- baggy_trough 6y ago
  They are not merged - Saturn is about as far away as a moon diameter right now.
  - gandalfian 6y ago
    Aha the pale dot just diagonally top left of Jupiter must be Saturn then. From my skymap they appear to be touching so I assumed the seperate extra dot was m73 star. Now I know better. Much apreciated. Thank you for the reply.
    - Stratoscope 6y ago
      Sky Map shows the planets much larger than they really appear in the sky.
  - stblack 6y ago
    The moon's diameter is about 0.5°, same for the sun, give or take — think total or annular eclipses, they are very close in angular diameter, if not equal for all practical purposes. At this moment, December 5, 2020 at 4:20 PM Eastern, Jupiter and Saturn are 1.74° apart. So about 3.5 moon diameters apart right now. Estimating angles in the sky is very difficult. It's also subject to perception illusions, like the "Horizon Effect" in which the Sun and Moon appear larger that their 0.5° diameter when, in fact, there's no difference. Some say this effect explains why your penis looks small when you gaze down at it. It's hard to judge, sometimes.
- jfk13 6y ago
  I've also been enjoying the view from the UK (weather permitting). I don't have a telescope on hand, but realised this autumn that my camera -- nothing special, just a Panasonic bridge camera -- could clearly pick out the four main moons of Jupiter, so we could watch how they moved around the planet from night to night.
quercusa 6y ago
I'm already dreading the emails my relatives will be forwarding me about this. (Anyone ever get "Mars will look larger than the full moon"?)
- pmiller2 6y ago
  It could be worse: https://en.wikipedia.org/wiki/The_Jupiter_Effect https://en.wikipedia.org/wiki/The_Jupiter_Effect
mrbonner 6y ago
I live in near Seattle so all bets are off. Buying a telescope is as wasteful as setting up your roof for solar panels.
sibeliuss 6y ago
Otherwise known as the Great Conjunction: https://en.wikipedia.org/wiki/Great_conjunction https://en.wikipedia.org/wiki/Great_conjunction
hsm3 6y ago
https://en.wikipedia.org/wiki/Great_conjunction https://en.wikipedia.org/wiki/Great_conjunction gives the exact time as 21 December 2020, 13:22:00 UTC, or 5:22 AM PST. In SF, the planets will set around 7:10 PM, the sun sets about 5pm. So if my best observation time will be around 5:30 or 6pm, seems like they will be at least as close if not better on the 20th as the 21st, right? And then even more so for HI, two hours later.
carlob 6y ago
Somebody is going to complain this is not reddit, but I think this is appropriate https://www.youtube.com/watch?v=jv0fIC-iPAA https://www.youtube.com/watch?v=jv0fIC-iPAA
rektide 6y ago
Solstice!! What?!?! I didn't realize they coincided.
- PrefixKitten 6y ago
  Such a wicked coincidence
thelastwave 6y ago
The last time this happened, Ghengis Khan was still alive.
legerdemain 6y ago
Tarva, the Lord of Victory, salutes Alambil, the Lady of Peace.

143 points by chmaynard 6y ago

According to ancient scripture, "when the three planets are in eclipse, a black hole like a door is open, evil comes, spreading terror and chaos". The archaeologist working on this back in 1914 estimated this would happen every five thousand years (if his assumptions for the signs representing "1" and "5" were correct). Fortunately, this isn't expected to happen until 2263. Still, in a 2020 full of surprises, having alignment of two out of three planets is too close for comfort. (just to make this perfectly green: no, this comment is not supposed to be taken seriously)

jrootabega 6y ago
Aziz light?
- ggambetta 6y ago
  Much better, thank you, Aziz. Aziz looks confused
- gruturo 6y ago
  AZIZ! LIGHT!
  - lifeisstillgood 6y ago
    oooohhh - OK now I get it ... thank you (spoiler - opening scene of the fifth element)
friendlybus 6y ago
Crystal green? Any kind of green
mcintyre1994 6y ago
Perhaps the Mayans were exactly 8 years out? :)
thebigspacefuck 6y ago
Three in alignment is called a syzygy. Apparently this occurrence in the house of Aquarius is particularly bad. There’s an X-Files about it.
dane-pgp 6y ago
Slightly more seriously, it's interesting to note that, according to Wikipedia[0]: > When studying the great conjunction of 1603, Johannes Kepler thought that the Star of Bethlehem might have been the occurrence of a great conjunction. ... A triple conjunction is a conjunction of Jupiter and Saturn at or near their opposition to the Sun. In this scenario, Jupiter and Saturn will occupy the same position in right ascension (or ecliptic longitude) on three occasions (due to apparent retrograde motion) over a period of a few months. Presumably the significance of a triple conjunction is that it explains the story of the Magi seeing a "star in the East", which then "troubled" Jerusalem when they arrived there, until it "went before them", and then finally "stood over where the young Child was".[1] [0] https://en.wikipedia.org/wiki/Great_conjunction#%E2%88%926 https://en.wikipedia.org/wiki/Great_conjunction#%E2%88%926 [1] https://www.biblegateway.com/passage/?search=Matthew+2%3A1-12&version=NKJV https://www.biblegateway.com/passage/?search=Matthew+2%3A1-1...
- antognini 6y ago
  In addition to that, while Kepler was lecturing on the Great Conjunction he was drawing the trigon [1] which shows how the locations of Great Conjunctions change over time. This drawing (consisting of a triangle inscribed inside a circle that gets shifted over time), inspired him to pursue the idea that the distances to the planets were determined by polygons of different shapes inscribed in circles. This didn't work, so he moved on to Platonic solids, which worked better, but still not perfectly. Eventually this pursuit lead him to the idea of describing the planetary orbits by ellipses. [1]: https://en.wikipedia.org/wiki/Great_conjunction#/media/File:Keplers_trigon.jpg https://en.wikipedia.org/wiki/Great_conjunction#/media/File:...

deleted 6y ago

[deleted]

piker 6y ago

Not clear from the article if this is worth the effort of purchasing/setting up a telescope from rural SW England, but if any astronomers on can interpret how likely it would be to be visible under perfect conditions that would be really appreciated. Viewing this could be a great experience for a family over Christmas during the brief UK lockdown reprieve.

jankotek 6y ago
You need very good location with unobstructed view over western horizont. Some preparation and a bit of luck with weather. It is not a rocket science. But get telescope in any case. Even cheap stuff from Lidl will show some details on saturn rings and cloud belts on jupiter. And there is also Moon and stars..
- lifeisstillgood 6y ago
  Do you have any good (ie busy father orientated) instructions on buying and setting up a basic telescope ?
  - bartman 6y ago
    Take a look at https://skyandtelescope.org/wp-content/uploads/3-scopes.pdf https://skyandtelescope.org/wp-content/uploads/3-scopes.pdf for a good overview of 3 typical entry level suggestions. I have the Onesky (or rather it’s European sibling the Heritage 130P) and enjoy it. It doesn’t have any fancy features, but is easy to move around, doesn’t take up much storage space and still has plenty of power! If you’re willing to spend some more, the Celestron NexStar 5 and 6 are solid telescopes that can automatically move to specific objects in the sky (this is called GoTo) which is really nice if you want to focus more on viewing objects rather than finding them. They’re low on maintenance too and work well for showing others objects in the sky as they can keep whatever you look at centered in the eyepiece.
  - jankotek 6y ago
    binoculars on tripod, if youwant planets then 7cm basic refractor

thomc 6y ago

My wife gave me my Christmas present (a telescope) a little early this year so that I could practice and hopefully be ready for this event. I've had a few sessions already and it feels really special out in the cold night looking up at Mars and other planets whiz by. It does need some preparation though. I've got my site on a hill selected with no obstructions, the telescope has been collimated (calibrated), red dot finder is alligned, I've learnt how to setup the equatorial mount and polar align it, and I have my blue filter for clearer visuals of Saturn and Jupiter. Meanwhile I'm out in the back garden checking for clear skies any chance I get. One thing to know though, you won't see the planets as they often appear in pictures, those are usually made from hundreds of long exposure shots stacked and processed to bring out the detail. You pretty much just see small bright spots in the sky with a little surface detail if your optics are good enough. There is something about seeing far away planets with your own eyes however which feels magic and photos can't compare to the experience.

bamboozled 6y ago
I’ve lived almost this exact experience during winter after borrowing a telescope from a close relative. I could make out the rings of Saturn from my backyard and it was a special type of magic, an unforgettable experience the first time it happened.
- wdfx 6y ago
  I bought myself my first scope this summer and have been watching both Saturn, juipter and now mars on occasion as they've precessed across the evening sky. Same feelings for me, it's magical to observe first hand with analogue optics and eyeball these planets :)
sizzzzlerz 6y ago
Sounds like you've made a good start, if you're a first time scope owner. Even a modest telescope can provide you views of the solar system as well as deep sky objects that can take your breath away. If I could, a couple suggestions that can enhance your enjoyment of your scope as you become familiar with it and the sky. First, keep a log of each viewing session. Note time and date, location, sky conditions, what you viewed. If you're so inclined, make sketches of what you see. Its nice, later on, to have a record of what you've look at and how it may have changed when you go back to it. Second, find a local astronomy club you feel comfortable with. Most people will go out of their way to help a newbie. Attend any star parties that they may hold. They're great ways to see how others work and to see what other types of scopes can do. You will also learn how to better use what you have. In any case, enjoy your scope. They can be great fun and they really bring home how wonderous the skies are.

mellosouls 6y ago

Another nice summary here courtesy of the Beeb (more of a UK focus): https://www.skyatnightmagazine.com/advice/skills/great-conjunction-jupiter-saturn/ https://www.skyatnightmagazine.com/advice/skills/great-conju...

gandalfian 6y ago

I have been watching the bright blob of Jupiter (UK) this winter and assumed that to the naked eye Saturn was just merged in there too close to seperate. Is this right or was one of the near by stars actually Saturn and I didn't realize? Thanks

baggy_trough 6y ago
They are not merged - Saturn is about as far away as a moon diameter right now.
- gandalfian 6y ago
  Aha the pale dot just diagonally top left of Jupiter must be Saturn then. From my skymap they appear to be touching so I assumed the seperate extra dot was m73 star. Now I know better. Much apreciated. Thank you for the reply.
  - Stratoscope 6y ago
    Sky Map shows the planets much larger than they really appear in the sky.
- stblack 6y ago
  The moon's diameter is about 0.5°, same for the sun, give or take — think total or annular eclipses, they are very close in angular diameter, if not equal for all practical purposes. At this moment, December 5, 2020 at 4:20 PM Eastern, Jupiter and Saturn are 1.74° apart. So about 3.5 moon diameters apart right now. Estimating angles in the sky is very difficult. It's also subject to perception illusions, like the "Horizon Effect" in which the Sun and Moon appear larger that their 0.5° diameter when, in fact, there's no difference. Some say this effect explains why your penis looks small when you gaze down at it. It's hard to judge, sometimes.
jfk13 6y ago
I've also been enjoying the view from the UK (weather permitting). I don't have a telescope on hand, but realised this autumn that my camera -- nothing special, just a Panasonic bridge camera -- could clearly pick out the four main moons of Jupiter, so we could watch how they moved around the planet from night to night.

quercusa 6y ago

I'm already dreading the emails my relatives will be forwarding me about this. (Anyone ever get "Mars will look larger than the full moon"?)

pmiller2 6y ago
It could be worse: https://en.wikipedia.org/wiki/The_Jupiter_Effect https://en.wikipedia.org/wiki/The_Jupiter_Effect

mrbonner 6y ago

I live in near Seattle so all bets are off. Buying a telescope is as wasteful as setting up your roof for solar panels.

sibeliuss 6y ago

Otherwise known as the Great Conjunction: https://en.wikipedia.org/wiki/Great_conjunction https://en.wikipedia.org/wiki/Great_conjunction

hsm3 6y ago

https://en.wikipedia.org/wiki/Great_conjunction https://en.wikipedia.org/wiki/Great_conjunction gives the exact time as 21 December 2020, 13:22:00 UTC, or 5:22 AM PST. In SF, the planets will set around 7:10 PM, the sun sets about 5pm. So if my best observation time will be around 5:30 or 6pm, seems like they will be at least as close if not better on the 20th as the 21st, right? And then even more so for HI, two hours later.

carlob 6y ago

Somebody is going to complain this is not reddit, but I think this is appropriate https://www.youtube.com/watch?v=jv0fIC-iPAA https://www.youtube.com/watch?v=jv0fIC-iPAA

rektide 6y ago

Solstice!! What?!?! I didn't realize they coincided.

PrefixKitten 6y ago
Such a wicked coincidence

thelastwave 6y ago

The last time this happened, Ghengis Khan was still alive.

legerdemain 6y ago

Tarva, the Lord of Victory, salutes Alambil, the Lady of Peace.