APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 4199
Joined: Fri Dec 04, 2009 3:27 am

APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Post by APOD Robot » Tue Dec 08, 2020 5:05 am

Image Great Conjunction over Sicilian Lighthouse

Explanation: Don’t miss the coming great conjunction. In just under two weeks, the two largest planets in our Solar System will angularly pass so close together in Earth's sky that the Moon would easily be able to cover them both simultaneously. This pending planetary passage -- on December 21 -- will be the closest since 1623. Jupiter and Saturn will remain noticeably bright and can already be seen together toward the southwest just after sunset. Soon after dusk is the best time to see them -- because they set below the horizon soon after. In mid-November, the Jovian giants were imaged together here about three degrees apart -- and slowly closing. The featured image, including a crescent moon, captured the dynamic duo beyond the Cape Murro di Porco Lighthouse in Syracuse, Sicily, Italy.

<< Previous APOD This Day in APOD Next APOD >>

FLPhotoCatcher
Science Officer
Posts: 196
Joined: Wed Jul 18, 2012 6:51 am

Re: APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Post by FLPhotoCatcher » Tue Dec 08, 2020 7:30 am

Hi everyone, long time, no see.

I've heard that the conjunction will be the closest since 1623, and also that it will be the closest in around 800 years. Which one is it?

canopia
Science Officer
Posts: 108
Joined: Wed Aug 15, 2007 12:09 pm
Location: Bursa, Turkey

Re: APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Post by canopia » Tue Dec 08, 2020 10:06 am

The conjunction in 1623 was very difficult to observe because it happened while the Sun was 12 degrees away. The other conjunction probably mentioned was in 1226, which had the planets rather easily visible in predawn skies.

Tunç Tezel
Last edited by canopia on Tue Dec 08, 2020 9:12 pm, edited 1 time in total.

vdix

Re: APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Post by vdix » Tue Dec 08, 2020 11:27 am

I wonder if a close alignment of the two largest planets will perturb the orbit of something significant out there

User avatar
Chris Peterson
Abominable Snowman
Posts: 15632
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Post by Chris Peterson » Tue Dec 08, 2020 2:28 pm

FLPhotoCatcher wrote:
Tue Dec 08, 2020 7:30 am
Hi everyone, long time, no see.

I've heard that the conjunction will be the closest since 1623, and also that it will be the closest in around 800 years. Which one is it?
It is the closest since 1623, and it will not be this close again for another 800 years.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

User avatar
orin stepanek
Plutopian
Posts: 6031
Joined: Wed Jul 27, 2005 3:41 pm
Location: Nebraska

Re: APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Post by orin stepanek » Tue Dec 08, 2020 2:29 pm

LighthouseJupSat_Saragozza_960_annotated.jpg

Amazing that the light of the lighthouse doesn't
overwhelm the light of Jupiter and Saturn! :shock:
You do not have the required permissions to view the files attached to this post.
Orin

Smile today; tomorrow's another day!

User avatar
Chris Peterson
Abominable Snowman
Posts: 15632
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Post by Chris Peterson » Tue Dec 08, 2020 2:34 pm

vdix wrote:
Tue Dec 08, 2020 11:27 am
I wonder if a close alignment of the two largest planets will perturb the orbit of something significant out there
No. First, they are aligned with the Earth, not with the Sun. But near perfect alignments with the Jupiter, Saturn, and the Sun happen every dozen years or so. The gravitational effects are small.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

User avatar
neufer
Vacationer at Tralfamadore
Posts: 17834
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Post by neufer » Tue Dec 08, 2020 4:31 pm

https://whenthecurveslineup.com/2020/02/20/1623-the-great-conjunction-of-jupiter-and-saturn/ wrote:
The Starry Sky : 1623: The Great Conjunction of Jupiter and Saturn
By Jeffrey L. Hunt on February 20, 2020

<<The 2020 Great Conjunction of Jupiter and Saturn is the closest conjunction of these giant planets since their conjunction in 1623.

The Jupiter – Saturn conjunction of 1623 occurred in the wake of the invention of the telescope, so observing was in its infancy; yet, the sky was full of planetary activity. A partial lunar eclipse (April 15, 1623) was visible throughout the Americas and in Central Europe, where the moon was setting as the eclipse reached its 90% magnitude. Venus passed Jupiter and Saturn in late June and Mercury passed the planetary pair less than two weeks later, when the planets were about 22° east of the sun. With the inner planets in the vicinity of the impending Great Conjunction and Mars reaching opposition (July 4, 1623), surely sky watchers were observing the planets’ locations to test and revise their planetary motion equations.

By the time of the Great Conjunction on July 16, 1623, the planetary pair was less than 13° east of the sun. By Civil Twilight, the pair was near the horizon at mid-latitudes. Without optical help, the conjunction likely went unobserved, even for those with recently minted telescopes. Even then, the observer needed some luck to find the conjunction.

In later years, two British publications stated that the 1623 conjunction was not observed. In 1886, the Monthly Notices of the Royal Astronomical Society state that the February 8, 1683, Jupiter – Saturn conjunction was the first observed “since the invention of the telescope” and that the 1623 passing went unobserved. The same statement was written in the Journal of the British Astronomical Association in 1897. Perhaps the conjunction was observed without optical aid and recorded from more southerly latitudes, when the planets were higher in the sky.

Did the two British publications make the statements out of parochialism, rather than from factual observations made around Europe regarding the first Great Conjunction observed with a telescope, or was this the first time that the conjunction fit into an eyepiece since the telescope’s invention? The February 24, 1643, conjunction was visible in the western sky during mid-twilight as well as the October 16, 1663, conjunction. At the second conjunction the planets were about 10° up in the southwest at one hour after sunset. However, at both conjunctions, the planets were nearly 1° apart. At the 1683 conjunction, the planets were close, about 0.2° apart, twice the separation of the upcoming event. While the two previous conjunctions were visible to the naked eye and individually in a telescopic eyepiece, the 1683 conjunction was the first observed with both planets simultaneously in an eyepiece. With a separation of 0.1°, the 1623 conjunction would have fit into telescopes eyepieces of that generation, but certainly those early telescopes were unwieldy to steer and hold steady, and the telescope operator needed some persistence during the days preceding the conjunction to follow the converging planets into bright twilight while they had sufficient altitude to observe them. So, while the British publications are accurate about viewing the planets simultaneously through a telescope, the two preceding conjunctions were visible to the unaided eye and individually through a telescope, and this does not speak to the issue as whether the 1623 conjunction when unobserved across all of humanity.

In recent times, Great Conjunctions occurred February 18, 1961; followed by a triple conjunction of the two planets in 1980-81; and the last occurred May 30, 2000, although this was difficult to observe.

November 29, 2020 Update: Patrick Hartigan from Rice University has generated a list of Great Conjunctions spanning 3000 years. The dates may be off a day or two from the actual conjunction dates. His list includes the following close conjunctions:
  • March, 1226, separation 2.1′, one-third the separation of 2020
    August, 1563, Separation 6.8′, slightly larger than 2020
    July,1623, separation 5.2′, slightly less than 2020, but not likely visible.
So how do we properly describe this? Closest since 1623? Yes, although not likely observed. Closest since 1563? Yes. This was easily visible in the morning sky. Closest observable since 1226? Yes, this was clearly visible as well.>>
-------------------------------------------------------
<<On October 10, 1604 a new star, as bright as Jupiter, was spotted
essentially between Jupiter and Saturn, which themselves were only 9
degrees apart. Kepler observed it carefully until it faded into the
sun's glare the following year, and later wrote a book De Stella Nova
in Pede Serpentarti (About the New Star in the Serpent's Foot).>>
.
After a ~ 12 year orbital cycle Jupiter returned to the region of the
"Serpent's foot" on the Twelfth Night/Epiphany 1616 to be meet not by
planets Saturn & Mars but, rather, by the planets Venus & Mercury.
.
Exactly, three lunar months after Epiphany was Easter (April 3, 1616).
.
On the first waxing quarter moon after that was ST. GEORGE'S Day
. - April 23, 1616 both Shakspere & Cervantes were dead.
.
. The next conjunction of Jupiter & Saturn was
. an extremely close one on July 14, 1623.
. Both in Cancer with the the Sun
-----------------------------------------------------------
.......... Transfiguration
.......................................................
. Rutland released from Tower August 6, 1601
.
Jupiter OCCULTATION of 8th 'planet' UR-ANVs: August 5, 1623.
.
. Maffeo BarBERini elected Pope URBANVIII: August 6, 1623
.
____ Anne Hathaway dies: August 6, 1623
_______ Ben Jonson dies: August 6, 1637
.......................................................
'Two feet by two feet will do for all I WANT.' -Jonson
------------------------------­------------------------------­-
https://en.wikipedia.org/wiki/First_Folio wrote:
<<The printing of Shakespeare's First Folio was probably done between February 1622 and early November 1623. (Ben Jonson wrote a preface & and 80 line dedicatory poem for the folio.) The first impression had a publication date of 1623, and the earliest record of a retail purchase is an account book entry for 5 December 1623 of Edward Dering (who purchased two); the Bodleian Library, in Oxford, received its copy in early 1624 (which it subsequently sold for £24 as a superseded edition when the Third Folio became available in 1663/1664)>>
https://en.wikipedia.org/wiki/Henry_Wriothesley,_3rd_Earl_of_Southampton wrote:
<<Henry Wriothesley, 3rd Earl of Southampton KG (6 October 1573 – 10 November 1624) was the only son of Henry Wriothesley, 2nd Earl of Southampton, and Mary Browne, daughter of Anthony Browne, 1st Viscount Montagu. Shakespeare's two narrative poems, Venus and Adonis and The Rape of Lucrece, were dedicated to Southampton, who is frequently identified as the Fair Youth of Shakespeare's Sonnets.>>
Last edited by neufer on Tue Dec 08, 2020 11:38 pm, edited 1 time in total.
Art Neuendorffer

canopia
Science Officer
Posts: 108
Joined: Wed Aug 15, 2007 12:09 pm
Location: Bursa, Turkey

Re: APOD: Great Conjunction over Sicilian... (2020 Dec 08)

Post by canopia » Tue Dec 08, 2020 9:12 pm

Chris Peterson wrote:
Tue Dec 08, 2020 2:28 pm
FLPhotoCatcher wrote:
Tue Dec 08, 2020 7:30 am
Hi everyone, long time, no see.

I've heard that the conjunction will be the closest since 1623, and also that it will be the closest in around 800 years. Which one is it?
It is the closest since 1623, and it will not be this close again for another 800 years.
Actually, the conjunction on 15th March 2080 will be slightly closer than the one on 21st December.

Tunç Tezel

User avatar
neufer
Vacationer at Tralfamadore
Posts: 17834
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Between Saturn and Jupiter

Post by neufer » Tue Dec 08, 2020 10:50 pm

The Godfather Part II wrote:
Kay: “I know now that it’s over. I knew it then. There would be no way, Michael, no way you could ever forgive me.
  • Not with this Sicilian thing that’s been going on for two thousand years.
https://en.wikipedia.org/wiki/Capo_Murro_di_Porco_Lighthouse wrote:
<<Capo Murro di Porco Lighthouse (Italian: Faro di Capo Murro di Porco) is an active lighthouse located at the end of the Maddalena Peninsula on the south eastern tip of Sicily in the Area marina protetta Plemmirio, municipality of Siracusa on the Ionian Sea. The lighthouse, built in 1859 under the Kingdom of the Two Sicilies, consists of a concrete tapered decagonal tower, 20 metres high, with balcony and lantern attached to 1-storey keeper's house.>>
https://en.wikipedia.org/wiki/Between_Scylla_and_Charybdis wrote: <<Scylla and Charybdis were mythical sea monsters noted by Homer; Greek mythology sited them on opposite sides of the Strait of Messina between Sicily and Calabria, on the Italian mainland. Scylla was rationalized as a rock shoal (described as a six-headed sea monster) on the Calabrian side of the strait and Charybdis was a whirlpool off the coast of Sicily. They were regarded as maritime hazards located close enough to each other that they posed an inescapable threat to passing sailors; avoiding Charybdis meant passing too close to Scylla and vice versa. According to Homer's account, Odysseus was advised to pass by Scylla and lose only a few sailors, rather than risk the loss of his entire ship in the whirlpool.

Because of such stories, the bad result of having to navigate between the two hazards eventually entered proverbial use. Erasmus recorded it in his Adagia (1515) under the Latin form of evitata Charybdi in Scyllam incidi (having escaped Charybdis I fell into Scylla) and also provided a Greek equivalent. After relating the Homeric account and reviewing other connected uses, he went on to explain that the proverb could be applied in three different ways. In circumstances where there is no escape without some cost, the correct course is to "choose the lesser of two evils". Alternatively it may signify that the risks are equally great, whatever one does. A third use is in circumstances where a person has gone too far in avoiding one extreme and has tumbled into its opposite. In this context Erasmus quoted another line that had become proverbial, incidit in Scyllam cupiēns vītāre Charybdem (into Scylla he fell, wishing to avoid Charybdis).>>
Art Neuendorffer