Does this explain what generates gravity?

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I say this politely, Bonsai, but you seem to be severely dyslexic. Imminent and and serms ring alarm bells to me.

You are on the Autistic spectrum, IMO. Hope it helps.

I have actually read Galileo:

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

He was hard work. But obviously was unhapppy at the standard of Engineering at Pisa. But nevertheless used it for some experiments.

Leaning Tower of Pisa.jpg


The only thing I have seen that is worse in Engineering standards is Chartres Cathedral.

Chartres Cathedral 2.jpg
 
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If you think about it, you will see a worse standard of "engineering" if you look around.

In India, building owners keep adding floors to their buildings until they collapse into a dusty heap of rubble.

If you see the crumbed ruins from the recent Turkey earthquake, you will see something missing in the mountains of crumbled concrete - REBAR. Yes, they built the whole damn country out of concrete, sans rebar. Now thousands are dead because of this omission. And I doubt this is the only place in the world where such corners have been cut.
 
Serms there are many options.
That's part of the problem. That scope cost I mentioned - the thing it is mounted on may cost similar amounts.

Diameter means resolution. Bigger the better. Photography throws in another factor - long exposure times will reveal items that are too faint for the eye to see. Even colour but generally a cooled black and white ccd would be used along with filters. Or a dslr can be used but it wont be so sensitive. There is a good UK astro forum
https://stargazerslounge.com/
Where you can see what people use etc

Refractors - an old saying was an amateur's 4" refractor is likely to match a 6in Newtonian. Refractor F15 achromat and reflector F8. The reflector doesn't have colour fringes. These days people want apo refractors. Good for star fields visually and also with camera. Quality varies but none are cheap.

Long ago a fairly famous French guy pointed out the advantages of an F6 8" Newtonian. Still fairly compact but needs a firm mount. Usually a German type that uses a counter weight to balance the scope. That increases weight of the kit and means a more rigid mount is needed.

A fork mounted 8" SCT - it's easier to produce a stable mount. They are pretty compact but performance will be a little worse than a good Newtonian, On these I would favour the models that use 2 fork arms rather than one and if photo's are going to be taken as far as I am aware a wedge will be needed.

Then there is the Dobsonian. A Newtonian on a very simple mount. No guidance and likely to be rather tricky for planets. Star fields - for visual use larger diameters capture more light into the eye. It's a cheaper route for that use.
 
If you think about it, you will see a worse standard of "engineering" if you look around.

In India, building owners keep adding floors to their buildings until they collapse into a dusty heap of rubble.

If you see the crumbed ruins from the recent Turkey earthquake, you will see something missing in the mountains of crumbled concrete - REBAR. Yes, they built the whole damn country out of concrete, sans rebar. Now thousands are dead because of this omission. And I doubt this is the only place in the world where such corners have been cut.
There is a looming problem in the UK with aerated concrete. Very big cleanup bill coming for schools and public buildings.

We need Roman concrete!
 
That's part of the problem. That scope cost I mentioned - the thing it is mounted on may cost similar amounts.

Diameter means resolution. Bigger the better. Photography throws in another factor - long exposure times will reveal items that are too faint for the eye to see. Even colour but generally a cooled black and white ccd would be used along with filters. Or a dslr can be used but it wont be so sensitive. There is a good UK astro forum
https://stargazerslounge.com/
Where you can see what people use etc

Refractors - an old saying was an amateur's 4" refractor is likely to match a 6in Newtonian. Refractor F15 achromat and reflector F8. The reflector doesn't have colour fringes. These days people want apo refractors. Good for star fields visually and also with camera. Quality varies but none are cheap.

Long ago a fairly famous French guy pointed out the advantages of an F6 8" Newtonian. Still fairly compact but needs a firm mount. Usually a German type that uses a counter weight to balance the scope. That increases weight of the kit and means a more rigid mount is needed.

A fork mounted 8" SCT - it's easier to produce a stable mount. They are pretty compact but performance will be a little worse than a good Newtonian, On these I would favour the models that use 2 fork arms rather than one and if photo's are going to be taken as far as I am aware a wedge will be needed.

Then there is the Dobsonian. A Newtonian on a very simple mount. No guidance and likely to be rather tricky for planets. Star fields - for visual use larger diameters capture more light into the eye. It's a cheaper route for that use.
I’m leaning towards a Dobsonian. There’s one I’ve seen (6 or 8”) with tracking mount for a reasonable price. I’d have to add a fixture into the ground to mount the whole thing. I’ll definitely want to be looking at starfields etc.

The non tracking/non go to Dobsonians are really cheap but I get the feeling that without at least tracking, they are good only for visual work - ie not really useful for photography. There’s some really good iPad apps around now for finding your way around the night sky so go to is not really necessary in my view unless you want to be sitting inside in winter, whisky in hand, looking at stuff on your PC via Wi-Fi
 
I say this politely, Bonsai, but you seem to be severely dyslexic. Imminent and and serms ring alarm bells to me.

You are on the Autistic spectrum, IMO. Hope it helps.

I have actually read Galileo:

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

He was hard work. But obviously was unhapppy at the standard of Engineering at Pisa. But nevertheless used it for some experiments.

View attachment 1214538

The only thing I have seen that is worse in Engineering standards is Chartres Cathedral.

View attachment 1214542
Yes, my spelling leaves much to be desired, but the spell checker has a habit of mangling things up as well. I’m using Grammerly [sp?] on the PC which is pretty good- alas, not on the iPhone.

My large fingers, a source of endless amusement to my two sons, don’t help either. I tend to hit two letters on the iPhone keypad at the same time.

I’m on spectrum alright - somewhere around infrared 🤣
 
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Still mulling over my scope options. I have a kiwi mate who is a long term amateur Astro so I’m going to ask him as well. Serms there are many options.
If you are unsure of what sort of astronomy you want to do, and what the optimum for your location is, I suggest you rent some time on a scope and get a feel for what things can do, etc... eg, itelescope.net.
You can learn a lot about scopes, seeing, cameras, filter and software that way for a small outlay...
If you get serious you'll need to do that anyway, for objects in the southern hemi, or that plain don't get high enough at your latitude for decent imaging...
 
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just came across this quote...
“We've arranged a global civilization in which most crucial elements profoundly depend on science and technology. We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces.”
—Carl Sagan
 
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I’m leaning towards a Dobsonian.
I'd be inclined to feel that an F5 10" dobsonian is likely to be manageable. Light gathering power relates to the area of the mirror, piR^2 etc. An open frame type is very likely to need a cover to keep the light out and if it's a put it together to use type bear in mind that the mirrors need rather accurate alignment. Some use a hood over their head too to keep stray light out of their eyes.

There are equatorial platforms for them. Same idea as a wedge on a SCT. The angle is set according to latitude. With these the star fields don't rotate as their position is tracked during the night. A dobsonian can be balanced simply such that once positioned it stays put. I'm not sure that's the case when mounted on this type of platform.

A tracking alt az dobsonian will track but the view seen will rotate with time. In the past there has been mention of diy camera rotators to prevent this. No idea if this has been taken on commercially. For visual use it's not much of a problem. For camera work the exposure time is limited. However the price of cameras can limit that as well. It seems some do take decent shot with a dob and an alt az mount. Lot's of short exposures.

All in all goto is a good idea. You may not be able to see what you want to look at.

Setting up a tracking mount of any type is great fun. Some have the facility to add corrections due to things being a little bit off - actual direction of north and latitude. Maybe the scope is stood on a slight slope. This is usually done by re centering on some objected you have told the scope to slew to.

F ratio.- 8" F6 was dreamt up on the basis of being suitable for all of the usual uses. A Newtonian telescope can give near perfect image directly on axis. Coma creeps in further out from that. Faster F ratio makes it worse and increasing size does the same at the same F ratio. :) I wouldn't worry too much about this if I were you as correctors can be added if needed as can focal reducers. Star fields are usually viewed at low magnifications which will reduce the effect but in some respects small is beautiful. It's all a matter of compromise. Price usually has to figure as well.

One interesting factor is the current size of the draw tube for focusing. In the days when the 8" was dreamt up it was usually 1 1/4 inches. These days it's inclined to be 2". Even larger on astrographs which loose on resolution but gain on aberrations. However the size of the objects people generally look at are still the same size. In practice the 2" will get more light into the eyepiece as the F ratio gets faster and it allows them to be longer - mainly so that the focal plane is well out of the tube for photography.
 
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It was interesting to read that a corpuscular theory of gravity first proposed in 1690 was examined by a succession of famous physicists including Isaac Newton, James Clerk Maxwell and Richard Feynmann.

This kinetic theory of gravity is usually referred to as the Fatio–Le Sage theory, or colloquially as Push Gravity.

There have been attempts to revive the theory in recent years and, as the following link illustrates, as recently as 2023.

https://www.researchgate.net/public...iable_Form_of_FatioLe_Sage-style_Push_Gravity

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