One degree to go!

[john_morris_uk]

Mrs. S is good at Astro and often has to explain local time, UT and conversion of arc to time to beginners. Our household conversations are perhaps 'different' .........?

Yesterday's topic was use of selected stars to choose the best twinkles for a four point fix. We also talk about Strictly Come Dancing and whose gonna cook tea.

I remembering the realisation that selected stars are in the order that you need to try to shoot them, and with the ones with a best cross for a fix being marked with little diamonds. (I sort of got away without doing 'stars' for a long time!)

 

[john_morris_uk]

Happens every year, even more interesting Jupiter and Saturn will have the same azimuth quite soon and the closest conjunction in almost 800 years.

Indeed - but I hadn't noticed that the az of Jupiter and Saturn are about to be as close as they are. It's not something I look at very often...

 

[25931]

Indeed - but I hadn't noticed that the az of Jupiter and Saturn are about to be as close as they are. It's not something I look at very often...

and you are not alone in that

 

[capnsensible]

I remembering the realisation that selected stars are in the order that you need to try to shoot them, and with the ones with a best cross for a fix being marked with little diamonds. (I sort of got away without doing 'stars' for a long time!)

I sometimes think that symbol means 'the ones most likely to be hiding behind a cloud'.

 

[Uricanejack]

Indeed - but I hadn't noticed that the az of Jupiter and Saturn are about to be as close as they are. It's not something I look at very often...

Dec 21 1300 Z
Jupiter GHA 342 48.3 Dec 20 31.4 S Saturn GHA 342 48.2 Dec 20 25.2 S

The Altitude and Azimuth will of course Depend on where you are, Being first day of winter my chances of seeing it Not great.
They are low in the western sky for a while after sunset.
They should be close enough to see together with a telescope. Certainly with Binoculars.

1300 Z doesn’t work for either of us, now I have to figure out what it will be when I can see them.

 

[mjcoon]

Indeed - but I hadn't noticed that the az of Jupiter and Saturn are about to be as close as they are. It's not something I look at very often...

I pay attention to them because my telescope can just about reveal Saturn's rings to me. And easily reveals Jupiter's four evident moons allowing me to think about how Galileo worked out that they were orbiting...

 

[john_morris_uk]

Dec 21 1300 Z
Jupiter GHA 342 48.3 Dec 20 31.4 S Saturn GHA 342 48.2 Dec 20 25.2 S

The Altitude and Azimuth will of course Depend on where you are, Being first day of winter my chances of seeing it Not great.
They are low in the western sky for a while after sunset.
They should be close enough to see together with a telescope. Certainly with Binoculars.

1300 Z doesn’t work for either of us, now I have to figure out what it will be when I can see them.

Close together? Jupiter is very nearly eclipsing Saturn!

 

[LittleSister]

According to my reading of the runes (for hereabouts) -

Only 8 days until, on the 13th December, sunset starts getting later in the afternoon each day (though by then it's two minutes earlier than now, so it won't be later than today until about the 20th).

16 days to the shortest day, the 21st.

But we have to wait 25 days from now, until the 30th, before sunrise starts getting earlier again (by which time it'll be 17 minutes later than now, and we have to wait until January 24th before it's earlier than today).

I stand to be corrected.

 

[25931]

According to my reading of the runes (for hereabouts) -

Only 8 days until, on the 13th December, sunset starts getting later in the afternoon each day (though by then it's two minutes earlier than now, so it won't be later than today until about the 20th).

16 days to the shortest day, the 21st.

But we have to wait 25 days from now, until the 30th, before sunrise starts getting earlier again (by which time it'll be 17 minutes later than now, and we have to wait until January 24th before it's earlier than today).

I stand to be corrected.

Judging by the rather limited number of participants I suspect that I am not the only one who has not kept in practice

 

[john_morris_uk]

Judging by the rather limited number of participants I suspect that I am not the only one who has not kept in practice

Or perhaps you’re normal and not like some of us anoraks who happen to have a copy of the Nautical Almanac within easy reach? (I appreciate it’s available online.)

 

[GHA]

Round about now then

 

[GHA]

Or perhaps you’re normal and not like some of us anoraks who happen to have a copy of the Nautical Almanac within easy reach? (I appreciate it’s available online.)

Though these days as with many things google is quicker, and you don't have to get up
https://thenauticalalmanac.com/2020 Sun only- compact version.pdf

 

[38mess]

21st December, shortest day. Don't notice anything until late January when suddenly it's lightish at 5 pm

 

[GHA]

21st December, shortest day. Don't notice anything until late January when suddenly it's lightish at 5 pm

WOW!!!!!!!!!!
You mean it's less than 24 hours??

 

[capnsensible]

Add the word 'light' and all is revealed. I know you like Google. Try this sight (geddit) for ephemeis. Sun & moon times today, Arrecife, Canary Islands, Spain

Below is an extract for where I am:

Night 00:00 – 06:09
Astro. Twilight 06:09 – 06:38
Nautical Twilight 06:38 – 07:07
Civil Twilight 07:07 – 07:33
Daylight 07:33 – 17:56
Civil Twilight 17:56 – 18:22
Nautical Twilight 18:22 – 18:51
Astro. Twilight 18:51 – 19:20
Night

 

[Buck Turgidson]

without me having to look it up, when is the day with the shortest true solar time? Is that also the winter solstice?

 

[capnsensible]

So what you mean is get someone else to look it up for you. So as always, the Senior Service helps the crabs. ??

On the 21st December, Zurich will have its shortest daylight period.

Sunrise and sunset times in Zürich

?

 

[Buck Turgidson]

So what you mean is get someone else to look it up for you. So as always, the Senior Service helps the crabs. ??

On the 21st December, Zurich will have its shortest daylight period.

Sunrise and sunset times in Zürich

?

Ahh but as usual the senior service goes off and answers the wrong question

My question is on which day is the period from solar noon to solar noon the shortest? I guess its either some time in March or September when the equation of time graph is at it's steepest ??

 

[capnsensible]

Year’s earliest solar noon on November 2 | EarthSky.org

?

 

[Buck Turgidson]

Year’s earliest solar noon on November 2 | EarthSky.org

?

From the same page:

September 16th is the shortest day