andrew s

Given it was once said we would never know what stars are made of I think we know an amazing amount. I guess it's a matter of perspective. Regards Andrew

They don't. They make assumptions for example the "cosmological principle" and build theoretical models based on them. These are shaped by observation but put to the test but seeing how well there predictions match experiments. This is difficult for astronomy as we can't directly experiment but it can still be done. As an example, it is often said that space becomes discrete at the Planck scale but time of flight observations of light of different wavelengths from very distant astronomical sources does not support it. Similarly tired light is not supported by observation. On the cosmological red shift there are strong observations that support it. Tests of general and special relativity, the Layman forest the CMB and more. Alternative, theories do get published, say to avoid dark matter, but none as yet as been accepted as they don't explain other observational facts. In the end a scientific theory stands or falls on how it fits the data and its predictive power. Regards Andrew

A minor correction @ollypenrice we can see objects receeding faster than the speed of light. If I recall correctly the limit is currently about 3c. It's complex issue which is difficult to put in a post. The best I can offer is this paper https://arxiv.org/abs/astro-ph/0310808 The diagrams and maths are a challenge but the text is approachable if you accept the mathematics is correct - which it is. As per another threads real understanding takes hard work and definitely requires the wearing of underpants. Regards Andrew

By the way I think the age is right but the distances are wrong. From NASA: https://imagine.gsfc.nasa.gov/educators/programs/cosmictimes/educators/guide/age_size.html Age: 13.7 Billion Years Size: 94 Billion Light Years The most distant objects in the Universe are 47 billion light years away, making the size of the observable Universe 94 billion light years across. How can the observable universe be larger than the time it takes light to travel over the age of the Universe? This is because the universe has been expanding during this time. This causes very distant objects to be further away from us than their light travel time. For additional information, see Ned Wright's Cosmology FAQ. http://www.astro.ucla.edu/~wright/cosmology_faq.html#ct2 Regards Andrew

Not directly related to your issue but ZWO released new drivers etc. in early Jan that solved the issues I was having with my ASI 294mm pro. There is also a firmware update for the ASI120MM. Regards Andrew

As has already been said it's because light from further away has not reached us yet. The light from furthest away we can detect is the CMB. Every day we see a little bit further as light from the CMB seeeps past us. The light from the CMB is not the oldest/furthest signal we could possibly detect. In principle we could detect gravitational waves from before the time of last scattering that released the CMB radiation. Regards Andrew

I had a similar issue and was told by ZWO on their forum it was due to ice crystals. The cure for me was to cool the sensor slowly. I run a script that cools it to 0 then waits 2mins then in 1 degree steps down to -10 with a two minute wait each step. Regards Andrew

Well there is in the software I use including ASCOM, The Sky X and Voyager. It must be a hangover in SharpCap. However, I now see what you meant. Regards Andrew

Not sure what you mean but see this: " Offset is exactly as its name implies: it is an offset that is applied to the histogram curve which shifts it – offsets it – farther to the right on the histogram by some amount. This ensures that the minimum value that any pixel might record is not underexposed and is therefore clipped in the blacks. This is especially important in astrophotography because of the nature of it – some pixels on the sensor might be positioned to look at purely dark space and therefore will collect far, far fewer photons than pixels that has the light from a star, nebula, or other light-producing object pouring into it. Avoiding clipped-black pixels means that you avoid having pixels with insufficient signal or, worse, a value of 0. This is the opposite predicament of an image that has pixels that are clipped-white. Both types of clipped pixels effectively have no data that can be meaningfully acted upon during processing." From here https://daleghent.com/2020/08/understanding-camera-offset Regards Andrew

What did you have in mind? Fog is an excellent blocker or scatterer from UV through visible to IR. Regards Andrew

Ii was going to post this in it's own thread but my wife and I both observed the large sun spot with the naked eye . The filter was the freezing fog that was dimming the Sun to safe levels. In addition the cloud/fog skipping across the surfacethere was a steady dark patch . On just getting home now I confirmed it with the Solar Data Analysis images. Regards Andrew

To be honest I don't see how this will help. Regards Andrew

I have an ODK and have never seen them. I would guess that they should be way out of focus so a reflection from the corrector/ filter etc. must be focusing them. Just a guess though. Regards Andrew

You will need a robust spider design to resist the torque changes as the Newt points to different altitudes. Maybe a truss of some kind like on the Hale 200" (but smaller). I seem to recall a schmidt camera design where focusing was done my moving the mirror with three fine lead screws. Regards Andrew

Yes instrumentation has taken astronomy to a whole new level. While still too expensive for most of us the latest sCMOS cameras have close to 100% quantum efficiency and ridiculous good noise performance. Long gone are the days of alchemy to enhance photographic film. Great image by the way. Regards Andrew

After fighting some hardware problems, consisting of a pc power supply failure and a ZWO guide camera that randomly froze any USB hub it was connected to, I managed to capture an exoplanet transit. Not spectacular or novel but its a first for me. Not the best data with some thin cloud about getting worse near the end. Still learning how to use astro imagej to process the data and how to optimise the signal to noise using a new cmos camera. Regards Andrew PS Top marks to Dave at Pixel Skies for fixing the PC and endless help with the camera.

Socks obey Fermi Dirac statistics and are fermions so two identical socks can't be found together. Regards Andrew

My rig is at PixelSkies and the service is excellent. It's a while ago now but at e-eye I think you had to manage your own roof although I may be wrong. At PixelSkies they manage the roof and place the telescope so it can always shut wherever it's pointing. I am not sure how many places they have left so I recommend contacting them soon. Happy to answer any specific questions you may have. I was second in and am now there longest standing client. Regards Andrew

No you need to understand the possible orbits. It's too complex to post simply so you will have to do your own research. Regards Andrew

No they are not geocentric. You can't have a grid crisscrossing the globe in geocentric orbits which are strictly limited. Regards Andrew

Not one but a whole train of satellites all in the same orbit one behind the other. The aim is to have a near continuous grid for communication purposes. Regards Andrew

My guess (and it is just a guess) would be satellite constellations. Regards Andrew

Yes it does. It managed very nicely before we existed and will carry on regardless once we have gone. Regards Andrew

It's very simple. It's what my English teacher thought was between my ears. More importantly, the Universe is totally unconcerned about whether we can comprehend it or not. It just is. Regards Andrew

Indeed there are. I recall looking into this some 50yrs ago. I can't remember the details but non equilibrium thermodynamics can drive the creation of complex molecules some of which can become auto-catalytic. These types of process can generate the pre life self replicating entities. When that transitions into life is a whole new debate on what is life. Regards Andrew