Green Baron

Are we exchanging positions ? 28N/18W. As to Epox' suggestions: I am fine with those, only if they are too hig h in the sky exposure time will be limited as the camera might hit the leg of the mount.

The information about the motivation, purpose and instrumentation of and for the jwst is on the jwst web site: https://jwst.nasa.gov/ Exoplanets are not jwst's main purpose, though new questions will surely come up with it's discoveries. Exoplanets are better done in the future with big ground based telescopes with 30 and more meters diameter. No telescope can actually take a photograph of an exoplanet (if it's not a giant Jupiter far from its star in planetary disc perpendicular towards us). That star flickers, and the period and intensity of the flickering *alone* is what lead to the planet discoveries of the Trappist-family.

That is a question a cat owner waiter must bear :-)

Not wildlife, in contrary. News from domestication, one of my favourite subjects. Today, CATUS, the domestic cat, wild form Felis silvrestris ... lybica. http://www.nature.com/articles/s41559-017-0139 I asked my cat whether she remembered hunting in the dry Northafrican sands. Apparently not, she stood up, stretched, walked to the food plate and looked at me as we would look at the waiter when our mug is empty. Wildlife, eh ?

Ok, one of the nebulae it is then. Is the swan up already ? Man, time flies ... also think i saw Scorpius' tail a few days ago when driving. So Sagittarius is not far. The galactic centre rises 40° high here ... It starts to condensate now, so probably no night shift tonight. But i saw on the charts that in a few days the month long phase of westerly winds might end and give way to the usual tradewinds, which puts me on lee side with a much greater chance of clear nights. Ateriods ... hm ... i am more inclined towards deep sky, that's what my stuff is best suited for. I would expect one does it easier with a 50cm or larger aperture (roids are dark companions), corrected and even field and several consecutive nights for obtaining orbital elements. But i am not sure ...

It's not the wind, it's temperature. Air molecules at 20°C are fast (500m/s or so). "swoosh" *gasp* ... But, if you can make a gravity generator :-/ you might tame molecules as well. Herding the fleas. Edit: sorry, @kerbiloid, i didn't realize your post !

Morons don't analyse and do away with problems. Request rejected :-) You mean the primary mirror was not reflecting parallel to the longitudinal axis of the tube ? Could the uneven vignetting be the result of the secondary not being offset (set off ?) ? Or, as you mention the corrector, could the weight of the queue of corrector, adapters and camera warp the focuser or tube ? That for example makes my newton difficult to use for photography, but is has only a plastic tube (carbon fibre design, very trendy *rolleyes*). Do you use this for collimation ? It is done in seconds if your main mirror has a centre marker ... I do see a slight chance that there is an open sky tonight. Will aim at M81 in preparation of our project if this is the case.

No need for sentimentalities, it is part of the mission to let it dive through the rings and into Saturn's atmosphere. It is about getting the most out of the mission before the machine fails or might complicate future explorations.

This is not possible. fov is the outcome of the telescope's focal length/aperture and the camera chip's size. Different telescopes have different distortions and errors, the more of it the farther away from the center of the image. Some here can switch focal lengths through the help of optical compressors or expanders (aka reducer or barlow-lens) or by using different foci of the telescope (primary/cassegrain). In any case images from different systems must be rectified and aligned, that was what @kurja pointed to. These problems can only be solved by algorithms. Many here use the software PixInsight, which is, as far is i know, the most sophisticated for astroimaging. We only have to agree on an object that should then be put in the center of the image, to keep the different kinds of off axis aberrations as little as possible. Edit: images of larger fovs (like you guys with the f4 newtons) will simply have to be cropped to the fov of the images of the f/7 refractor users. This is not a problem in the ages of 8mp-cameras. And after all, we are not far away from each other when refractor- and schmidt-cassegrain-users mount their reducers. I think overall it's between f/4 and f/6 then. I think that's between 1 and 2 degrees fov in the sky. Take the moon as a reference. Andromeda galaxy will be a challenge for the project as for me there is nothing left to crop, it fits just well.

I knew it. I will actually have to read the book i bought :-) Just Read The Instructions, or, to say it clear, rtfm ... Overcast cloud cover down here. Up where the observatories are it's a steel blue sky. New moon today, eh ? Merde (J.L.Picard).

Yep, it'll force us to actually do something with the pictures than just stack them. Oh, btw., it's cloudy here ...

You can, of course, send a beam of light the long way over mirrors and things while you hike the short way. Then you're faster than light :-)

Nothing can go faster than light in spacetime, neither in special nor general relativity. Only the expansion of space can move things away from each other faster than light. Example It is not just an agreement or causality violation, it is an invariant. Any ftl are highly speculative theoretical thoughts and up to now all are just faulty when looked at them closely but none is actually based on observation.

It would be nice to have the source for the "superlimunal" thing that pop up every now and then. Ligthspeed is the limit. A particle at ligthspeed "experiences" the whole universe - infinite or not - in no time. Very short. All of it. Billions of billions of billions of years. And more. It's not negotiable, like you can't negotiate with the apple falling from the tree.

Ok, i limit myself to 16bit fits. It is probably best in my case to just submit the calibrated light frames (darks and bias subtracted) because bandwidth. Right now it is overcast :-(

Nice. Am not a biologist, but could try to help if it comes to Palaeontology, "that-what-is-old" literally translated, but in principle its about how the living realms formed on earth.

Good idea ! How about M81 ? Or any other suggestions ? In summer M31 ? I could deliver b/w images in fits format, LRGB filterset, picture size is a 4/3 with 8mp. Or 12mp colour from a nikon dslr, maybe in summer for the mosaic ... Should we agree on a specifc format ? Fits ? Aww ... sh.. i only have satellite connection and 20gb per month. That is easily exceeded with a stack of fits or tiff images ...

Superluminal doesn't exist. If you refer to the universe outside our hubble sphere, it is gone and won't come back. Impossible to interact with or reach. Say good bye :-) There is nothing superlimunal or extrauniversal about dark matter. It is right here, it explains extra gravity, it grows over time but it doesn't interact otherwise. That makes it difficult to observe. For now.

nothing is as uninteresting as the part of the runway behind you unknown

The Lord of the Rings

"I'm the schmuck who landed on the taxyway !" Harrison Ford

Planet 9, if it exists, is very far out, much farer than the irritated kbos that are all following the same pattern), between kuiper belt and oort cloud. Scroll a few pages up for the postulated orbit. And, yes, it is assumed to be a dark rock. Its orbit is (if it exists) highly eccentrical, thus it loiters a lot of time far away with little haste. Also it might be responsible for the tilt in the ecliptic of the planets. Like many other eccentrics before, after it was done with disturbing its prissy fellows they sent it off to go play somewhere else :-) If it exists ...

lol, that fits. Such empty slogans have a connotation in the topic we shall not talk about and dispensation of law :-), expressing a personal view (or in this case probably the lack of it). As to Planet Nine, there is an update on the blog of the postulaters. A few newly discovered kbos fit right in the postulation. But we have to be patient until the first snapshot, maybe wait for the next generation of telescopes.

Since most are bashing the IAU and it's trespass against Pluto's state among the family of solar system objects i state that i find the definition of planet and dwarf planet comprehensive, clear and constructive. Until it is changed again, of course, because of new insights in the forming of solar systems. I am missing a definition of moon, since the discussion about the moon's orbit in another thread ... Yes, a duke is lesser than a king ... :-)

A portrait would be best. I shortly heard of other kbos orbits that fit well in the predictions.