Astro Noodles

Thanks Alan. I had to loosen the grubscrews slightly to get it to budge.

I have a SkyWatcher Starquest 130p and I would like to use it for astrophotograpy. Can anyone recommend a replacement focusser which would give enough inward focus for this telescope?

Thanks Alan.

I know this is a stupid question, but what does the silver screw at the top actually do?

I'm just a newbee at this, but it does seem that longer exposure = more photons captured. So I would have thought it would be extremely difficult to capture enough data on dim DSOs. Of course, I am looking forward to being proved wrong on this and anticipating eagerly the next Youtube video.

I've found the solution! Rev'd Merryweather's Tempest Prognosticator. It seems to run on leeches - and electricity. 😄 Tempest Prognosticator – Whitby Museum

I can't help asking. When are you expecting it to be 29C at night in the UK?

Hi and welcome to SGL.

FLO have just contacted me. What a joy they are to deal with. They have tested the Skyguider Pro and agree that it is not functioning correctly so have sent out a replacement. I am very happy. 😀

So the thinking is that dark matter is going to turn out to be a combination of thing? Axions, other exotic particles and primordial black holes, and maybe other things as well?

I have been thinking about dark matter lately (it's been very cloudy here and my job is boring). When I first heard that it was a thing, and was necessary for current theories to work, I thought 'Why does there need to be dark matter, can it not just be ordinary matter that we can't see, and black holes and stuff?'. Then I learned that It didn't interact with anything, and there had to be more of it than actual matter so I thought 'OK'. I have been watching some things on Youtube and now I see that black holes are being mooted again. Can anyone explain the current thinking on this?

It's certainly the way I know I'm learning something. I'm certainly enjoying these personal tutorials.

Thank you all for sharing your knowledge, especially @vlaiv for the detailed explanations. As you will know, I now have many more questions than I started with. 😁

😁😁😁

So, back to the original question for a recap of what I think I know now. 😁 So, an object can be said to be 10 billion light years away if the light travel time between that object and my instrument is 10 billion years. The light travel time is affected by Hubbles law which uses the red-shifting of light to determine the rate at which an object is accelerating away. Also, the expansion of the universe. So it would be possible to say that an object was perhaps 10 billion years of light travel time away as observed. But it would also be possible to say, for example that it is 20 billion light years away in distance due to Hubble's law and expansion. Furthermore it can be stated that the two results are not in conflict with each other because they are measuring different things. And then it is also true that 20 billion light years away is not a paradox which makes the object older than the universe, it is just an artifice caused by the standard of measurement selected which is not really appropriate in this case. Am I on the right track with this? I can see that the way a question is asked can be just as problematical as providing an answer. Terms of reference and definition are key to this. As I now understand it, asking a question like how far away is the edge of the universe is like asking how far away is forever?

Are you able to order from abroad?

That's an amazing image

Thanks Vlaiv I'm currently working my way through everything that Anton Petrov has posted. Working from home, I need something on in the background. I know it's not the ideal learning technique but I can always watch them again in the hope that some of it will sink in. 🙂

Your friend makes a salient point. GR and QM ask people to fundamentally re-evaluate their perception of reality. It is all backed up by extremely complicated mathematics which is far beyond the ability of most people to understand which is why people have the problems with comprehension. We non-Theoretical Physicists have to rely on the words of those teachers who have spent many years of study to achieve the level of understanding and skills necessary to formulate theories and test them. However, (if they take any interest at all) many people tend to react against anything that has experts or academics telling them what they should think or do. Especially if they are told that they wouldn't understand it anyway even if if it was explained to them. This is certainly not meant to be a pop at science or scientists in any way. I do feel like academia is being undermined, and there is a increasingly large body of people who want to define their own reality/history based on how they feel rather than on evidence or research. I would dispute that most people have no problem understanding Newtonian mechanics and gravity. I would contend that 'most people' never think about it at all. People drive cars without understanding how an internal combustion engine works, ride motorcycles without understanding gyroscopic precession, use mobile phones, microwave ovens, the internet etc with no conception of what it is that makes those things work.

There are certainly plenty of methods which have been used. It seems that at the moment, Hubble's constant is dependent on the measurement technique used. I notice that some techniques have returned quite a large potential spread of values as well, including the gravitational wave experiments. It is also interesting that the early universe techniques have returned lower values than those which have used distance ladder measurements.

I'm not making any assumptions. 🙂

If you budget will accommodate it it, then yes it seems like a good way to go. A word of caution, and it has been mentioned before, neither visual or AP are instant gratification pursuits. Buying a lot of high-end kit all at once may not be the best idea as you stand the chance of being overwhelmed as the learning curve becomes a tsunami. But, if you are confident, then why not. You can sell on any kit which becomes surplus in the future and recoup some of the investment. 🙂

I think the advice give here is absolutely correct. AP and visual are two different animals, and require different equipment. If you are looking in the $2000-$2500 range, it should be possible to get decent beginner level setup for both activities. For visual astronomy, you could start out with one of these Sky-Watcher Classic 200P Dobsonian | First Light Optics for £400 For an entry level into AP, you will need a DSLR (second hand Canons can be had for less than £150). And then you would need a German equatorial mount, These start from about £500 for one of these Sky-Watcher Star Adventurer 2i WiFi Pro Pack | First Light Optics with a sturdy tripod, to about £1000 for one of these Sky-Watcher HEQ5 PRO Go-To Astronomy Mount | First Light Optics Then you would need either a decent camera lens or a small apochromatic refractor, weight dependent on the mount you choose. These have a good reputation https://www.firstlightoptics.com/pro-series/skywatcher-evostar-80ed-ds-pro-ota.https://www.firstlightoptics.com/skywatcher-mounts/skywatcher-heq5-pro-synscan.html. With a flattener/reducer £700 but would be too heavy for the sky-guider. Then you might need several hundred/Thousand Euros/Pounds/Dollars for accessories/connectors/dew heater/laptop/viewing chair/eyepieces/filter etc - you see, the difficulty is not just knowing where to start as being able to stop once you have started. By the way, you could start out with visual and then move onto AP. You don't have to buy it all at once. 🙂

I don't think we were made to observe the universe. I think that we evolved senses to give us a competitive advantage in our own environment. Some creatures have very peculiar sensory systems which are different for our own - the ability of many creatures to navigate using the Earth's magnetic field springs to mind. I am just postulating that we might require different sensory equipment to broaden our understanding of the universe.🤔

It seems to me that cosmology as it stands is as much philosophical mathematics as anything that can be observed directly. The models will no doubt evolve as new observations either confirm their validity or not. Is the problem here something to do with perception? I think that what I'm trying to say is that humans are primarily a visual animal. And, unsurprisingly then our observations have focused on the electro-magnetic spectrum. Gravitational waves, as something entirely different will offer another perspective I imagine. Our other senses seem utterly inadequate for observing the universe beyond our immediate environment. The universe may be under no obligation to make sense to us. It may be under no obligation to be sensed at all by us.