What is the Universe expanding into..

[Fast Eddie D]

 

[Disco-Pete]

I will take no lessons on derogation from you.

You might do well to do so. You seem to be very adept at researching a thread for old posts. Perhaps you could research your own. You will discover you have been the sole instigator of negative conversation since you appeared here. And don't go bringing up mid stream posts after the fact. Remember that Seinfeld episode where Kramer retaliates against the chimp with "well he started it!"? Well I'm glad to inform you that the chimp is well represented here by you.

must be an ancestral trait I presume?

 

[system7]

At the risk of becoming a 'tidal bore', I offer Donald E. Simanek's take on the topic.

He explains that the tidal forces (shown by the vectors in the attached diagram) act on the Earth's volume in two ways:

(1) They stretch the "solid" earth along the earth-moon line, and (2) they move water, toward the earth-moon line.

"The second effect is dominant for ocean water, since water is nearly incompressible. It does not compress or stretch, but it is easily pushed around. The tidal forces push water toward the tidal bulges. Outside of the bulge the ocean surface is lowered."



Simanek says:

"While gravitational forces depend on the inverse square of distance, these tidal forces, being differences in force over length (ΔF/Δx), depend on the inverse cube of distance. That's why tidal forces on earth due to the sun are much smaller than those due to the moon."

https://dsimanek.vialattea.net/scenario/tides101.htm

A third power inverse relationship is a rarity in Physics. The Solar System would look very different if Gravity was an inverse cube Force.

https://math.ucr.edu/home/baez/inverse_cube.html

I mentioned Zeta(2) has a Physical interpretation as a row of planets evenly spaced. Some aspect of it works with a circle of planets or lights too.

https://en.wikipedia.org/wiki/Riemann_zeta_function

Einstein worked out that rotation under Gravity can be interpreted as zero rotation with a centrifugal force in a rotating reference frame. Or something like that...

Zeta(3) must be something to do with Tides.

Apropos poor understanding of Astronomy, my two friends at the Pub on Friday were unable to identify Jupiter which was right next to the fullish Moon.

The Moon has gone much further East tonight. And Lunar Eclipse on Tuesday, around 10.00AM UTC if you might have forgotten:

ps. Stop the bickering people. It's a distraction. Be cool, be nice. We have serious Physics to do! 🙄

 

[Galu]

Stop the bickering people.

Yes, too much monkeying around! 🙊

 

[Galu]

A third power inverse relationship is a rarity in Physics.

I read that Newton considered that the addition of a central force of inverse-cube nature could explain the gradual rotation of elliptical planetary orbits over time (apsidal precession - see attachment).

However his theorum of revolving objects did not account for the apsidal precession of the Moon without giving up the inverse-square law of gravitation.

I must admit, it's all impenetrable to a cubehead like me!

https://en.wikipedia.org/wiki/Apsidal_precession

 

[Disco-Pete]

We have serious Physics to do! 🙄

I’m certain I qualifiy to declare this is highly doubtful. 😉

 

[system7]

Serious Astronomy done this morning. Being concerned about Rain on our eclipse in Hong Kong tomorrow, I have been looking for alternative Telescopes:

Hawaii looks a contender. The Japanese are on it!

The optics are excellent and I even saw an Orionid meteor whist watching.

Here's a puzzle for the keen astronomers.

It wasn't twinkling, and it's not Jupiter! And it's not a meteor.

Hands up if you know the answer! 🙂

 

[system7]

Reference my claim to have seen an Orionid meteor: Pictures or it didn't happen, eh?

It was a whopper! A veritable FIREBALL! The size of a double-decker bus in layman terms. Never underestimate The Orionids.

😀

 

[Galu]

Great Balls of Fire by the Orionids.

I have it in my vinyl collection! 😀

 

[Galu]

Never underestimate The Orionids.

Some background for those not acquainted with the Orionids:

The Orionid meteor shower consists of particles of rock left behind in the wake of Halley's Comet.

Most of the shooting stars appear to originate from a point close to the constellation of Orion, explaining why they are called Orionids.

This star map from Wikipedia shows the point of origin, or radiant, in red:

https://en.wikipedia.org/wiki/Orionids

However, we are still left with the question, what is Steve's "Mystery Object"?

I think it is the International Space Station. https://spacestationfinder.com/

 

[system7]

I didn't know it was the debris of Halley's Comet. Thankyou for that. Not a bad guess on the mystery object, but we are not there...

Naturally further questions arise.

This place in Hawaii, known as Mauna Kea to the grass-skirt wearing natives, is at a gasping and vertigo-inducing and doubtless chilly 4205 meters. I was wondering why the sky and telescope domes were so light. Easy. It's near full moon.

It's all quite picture-postcard:

Looks like the surface of the Moon to me. It is now Zero minus 16 hours apparently. Can't wait! 😀

 

[Galu]

Is the "Mystery Object" an 'Artificial Star' formed using a powerful laser beam which is shot from the telescope into the sodium layer of the atmosphere?

 

[system7]

Excuse me for saying this, but most of you are just Dumb Clucks.

Here is the answer to the Riddle:

Barsoom. A Bonus point might be ascribed to anyone who notices that "Subaru" is the Japanese word for "The Pleides".

Anywhoo, system7 is off to bed. I have set my largely useless Android 'Phone to 10 AM UTC. And so should you. 🙂

 

[Galu]

Doh! You threw me right off target by employing the word "object"!

P.S. A lunar eclipse is not the most exciting of astronomical observations, dare I say, but I look forward to your images nonetheless.

 

[system7]

What you don't know, Galu, is the whole purpose of the splendid Subaru Telescope. We are not seeing the Primary 1.5 degree widefield instrument!

Amusing as the meteors were, they weren't the MAIN EVENT.

What the main adaptive optics thing is after, is Trans-Neptunian Planet Nine, a Kuiper Belt object:

https://en.wikipedia.org/wiki/Subaru_Telescope

This is a whole dimension beyond our current capabilities!

Tomorrow is just testing the software and hardware on a predictable astronomical target. But I am interested. 🙂

 

[Galu]

The Subaru Telescope's 900 megapixel ultra-wide-field (1.5 degree field of view) camera will be used for surveys of weak lensing to determine dark matter distribution - or so I read in Wikipedia.

 

[indra1]

... "Subaru" is the Japanese word for "The Pleides"...

Surely a spelling mistake there? ...
Good Mathematicians are known for precision.

Right. 😛

 

[system7]

Look, or as I prefer, "Hark" in Anglo-Saxon:

Have i ever claimed to be good in other Languages? I am highly autistic, and dyslexic, and spellning is not my strength.

I find it curious, having survived the Seven Sisters Road in London, aka The Pleiades, that I am still around. Thus it is.

We must observe this Eclipse. Surely not a dull moment? I am on it. Results soon.

BTW, Dyslexia Rules KO. 😀

 

[Galu]

What the main adaptive optics thing is after, is Trans-Neptunian Planet Nine...

As mentioned earlier in the thread, "Planet Nine" may be a primordial black hole the size of a grapefruit and a mass of around 5 to 10 times that of the Earth. Observing its gravitational lensing effects would be extremely unlikely, but it's just about conceivable that the Subaru's ultra-wide-field camera might spot them.

So, Subaru means the Pleiades or, as commonly called, the Seven Sisters - learning all the time!

When looking at the Pleiades, most people see six, not seven, stars and that would explain the Subaru car logo.

The Japanese name of the Subaru symbol is ‘mutsuraboshi’, which means six stars.

Around 14 stars can be seen with the naked eye if the conditions are right, although the open star cluster has more than 1,000 confirmed stars.

https://nineplanets.org/the-pleiades/

 

[system7]

To be honest, most of Today's events passed totally over my head.

What I can tell you is there was, last night, on BBC4, an excellent Episode of Bertram Wooster being saved by Butler Jeeves as usual:

The delayed Exit of Claude and Eustace.

https://www.bbc.co.uk/sounds/play/b007v1df

So many running Gags. Aunt Agatha amongst them. I knew Bertie's Eton Spats would get burnt by Jeeves, who is relentlessy Conservative. I am less certain where the Gold Cigarette Case ended up.

I may have missed something, but, TBH, I don't think so. A Plot Hole. What happened to the Cigarette Case?