andrew s

Is that just eccentric or monocentric? Regards Andrew

@JeremyS your a very naughty boy. Regards Andrew

Enjoy your rig there. Dave and Michelle are great hosts. Regards Andrew

Both are moving away from the earth. Regards Andrew

Rubber cups are for wimps. I have had my eye freeze to a brass eyepiece. No wonder I gave up visual. Regards Andrew

I am not an expert but as at focus the eyepiece gives parallel rays the eye would be relaxed and focused at infinity. It can tolerate small amount of defocus caused by, for example, seeing but not more. This link may help https://www.telescope-optics.net/eye.htm with a general overview of the eye/telescope. Regards Andrew

It's a long time since I looked seriously at this. It's explained in part 3. For a given rig you observe standard photometric stars and then use these to calculate the linear fit constants I.e. an adaptive and multiplicative constant. Regards Andrew

As explained in the link this assumes you have a wide slit so that you collect equally all the wave lengths. Obviously, it depends on how accurate you want it to be. However, there are many issues for example atmospheric effects if the known star and target star are at different altitudes. It's certainly not as easy as differential photometry. Regards Andrew

This may help. Regards Andrew

No, just giving up observing. I am still keeping up with developments in general. I hope the JSWT will give us some new insights before I retire from life completely. 😊

I always enjoyed building telescopes and instrumentation as much as using them. However, the time has come to take them all apart and sell them on. Look out for a flood of bargains! I will advertise the first on SGL for what I think is a fair price but will consider discounts and offers from long-term members. This is just the tip of the iceberg the Paramount and ODK are to big for the loft! Regards Andrew

Looks like legitimate technology to me. See the second link I cross posted with your reply. Also this on sreak cameras . Regards Andrew

A quick search found this https://www.caltech.edu/about/news/ultrafast-camera-takes-1-trillion-frames-second-transparent-objects-and-phenomena and https://www.popularmechanics.com/technology/design/a32434104/worlds-fastest-camera/ Regards Andrew

I posted my results on the AAVSO site although there is/was a bug in the search which had not been fixed when I retired from observing. A bonus is NASA may pick up your data! The BAA data base does not take relative flux which is the normal. Nice start, well done. Regards Andrew

@iantaylor2uk has it right. The particles are moving faster than the speed of light in air.

My Paramount ME II gave about 0.9 arc sec peak to peak after training out the periodic error. Regards Andrew

Very productive, he is.

Very interesting. Do you know if it preserves the photometry? Regards Andrew

Oh you engineer. Remember we would not be here but for quantum mechanics. Classical atoms are unstable. Regards Andrew 😌

Indeed they have. They are dilute beams so that on average only one photon goes through at a time. The beam is not a single photon state in the sense I intended. Regards Andrew PS It might be worth adding for those less familiar with the topic that a single photon doesn't make an interference pattern. It just makes a localised "hit". You have to pass a large number of single photon throught for the pattern to appear in line with the quantum perdition. Or better still prediction . Thanks @MalcolmP.

They have to be energetic enough to produce pair production. Then they can cause a star to collapse into a super nova see here Regards Andrew

That was my incorrect post 😊 Solar sails are the only macroscopic example I can come up with. Regards Andrew

In essence that is exactly what it is. However, the connection between light and normal matter is demonstrated by pair production where a high energy gamma ray can produce an electron positron pair. Similarly, a particle and its anti-particle can annihilate to photons. Regards Andrew

Incorrect post removed

This gives the experimental rest mass as less tha 10^-48 kg. The photon is the most enigmatic of quantum particles. From a quantum field theory perspective it is a localised excitation of the field. However, its location is impossible to measure, most states of the field don't have any meaningful number of photons and it's very difficult to create single photon states! I could go on. Regards Andrew