Green Baron

I find this funny :-) Are you working with different scales here, to suit a personal conception of what is "good" or "bad" ? A tiny scale (x/1000) is used for the impact of radiation and emission of green-house gases by conventional means of power generation to show that this is not that bad and nobody dies of it, and a huge scale (x*1000) is used to illustrate imaginative dangers of a renewable energy. Germans have a word for that "Stammtisch Politik", illustrating the discussion of politics by those members of a village between mugs of beer in a local pub who have problems with a change. Nothing good comes from that :-) Like the hobbits in the lord of rings :-) Sorry, no offense, but i just couldn't resist to overlook it from a distance. But i think you must admit that it has a political touch. Sure, not everything is gold, but we will not change the world the one or other way in a game forum :-) http://www.iea.org/topics/renewables/subtopics/wind/ Edit: i got a 1:50 die cast scale model of the crane with the lattice jib. It stands tall. Very tall.

@wumpus: i would guess that behind a tower or antenna there is an effect as well, like shown f.e. by the accumulation of silt on the leeside od an obstacle, depending on the windspeed and direction. But surely few care about this. It plays a role in the planning of development a city (pressure changes, wind-dynamics, ...) but not on a regional scale. Noone cares about the effects of warming in and behind a city, though we are talking about many degrees here (temperature above concrete vs. above forest/meadows, sealing of the ground, changes to evaporation of surface water, ....). I think that, as the discussion about alternative energies is changing the way we think and consume (it does change mine :-)), a lot of it is exaggerated in the one or the other way, depending on "what side your on". Sorry if this sounds a little ... comical, but there are substantial economic interests involved. The energy markets of the countries i know (i do not know the USA, fill me in !) are often oligarchic, few companies divide the market. That is not exactly a recipe for a change. In some countries the installation of alternative energies, namely solar power, is highly encouraged, even subsidized, but not so here. You are not allowed to produce energy and feed it into the grid (like in Germany, where you get paid a little), instead you must disconnect or make sure that nothing gets out (technically not a problem). Some say this is because the company is in bed with the decision makers. But things change under public pressure, it just takes a while :-) @tater: I hate to link to Wikipedia ... but this might solve your problem. *duckandcover* :-)))) Edit, yes how silly from me .... there are more sophisticated methods for felling a windmill. :-)

Well, i agree with the uglyness and noise and some sites could have been chosen more wisely (though i wouldn't call it criminal), but the power output is not that bad and i wouldn't say it is silly. A decent turbine produces 2-6MW if the wind blows (needs less than one might assume), some of the offshore parks produce power in the range 0.5GW and slightly more. That's not as much as a nuclear or fossil powered power plant can do but wind energy can contribute its part. We just don't want it right in front of out door. The "ugliness" of a nuclear or a correctly cleaned coal power plant is just less visible to the human eye ... btw: in front of the door of those on the other side of the island, above Santa Cruz, is a heavy oil power plant with a constant smelly blue cloud over it. I wouldn't want to live there, people often complain about the bad air. But the power company is state owned and of course everything is in compliance with the rules ...

Finding the right mix indeed is the biggest technological challenge, together with means for storage and distribution. A grid for power distribution for renewables has to be much more flexible due to the inpredictability. Edit: ... that leads us to home made electricity, if local conditions permit. Quite a few here (San Miguel de La Palma) have disconnected themselves from the public grid.

Yes. Though i believe that on- or offshore windparks could provide a good part in renewable energies ...

@Darnok, i probably didn't hit the right tone in my responses, sorry if i upset you. I must admit that posts like (sloppy) "look i found out that climate care isn't as important as we all should believe" do in fact provoke me, that is my excuse. Nevertheless, i didn't mean anything personal, i'm not your enemy. But i'm not a teacher as well, searching for publications on a special subject like the above takes a lot of time that i do not always want to invest. That might be the reason why you had the impression i was posting just an opinion. Of course, your impression was correct. Touché. :-) gb

Nope, wikipedia, newspapers and internet news magazines are not sources. The content is in no way controlled and endangered to serve the purpose to transport a message. So that should be taken with salt ;-) Dr. Miller mixes weather and climate and seems to use a climate model that suits his assumptions. He is, as i read, not a climatologist but a neurobiologist and i couldn't find any other publications of him on the subject, so i find it hard to take it serious. Climatology is a very complex field of earth science and from time to time driven by politics because much of it can be subject to interpretation. If you just post a link to a text that contradicts a main-stream view you should expect responses like mine ... :-) I'm not that much into local climate or weather phenomina since these are very difficult to model and put into numbers. In fact, measurements are often uncomparable since on a day with more sun you'll have completely (local) different temps/humidity/thermal winds than on a cloudy day. Regional weather changes or overlays the local conditions, seasons do and large scale circulations as well. But, as a peace offer, i change my response from "nonsense" to "i do not believe it". Peace ? gb

@Darnok: weather and climate are different things. No. The slight temp differences refer to a few .1 of degrees a few 100m behind the turbines. Data from social media is grossly misleading (disinformation), go to the sources ;-)

Browsing for Dr. Lee Miller i get the feeling that this is a "sponsored research". He doesn't even state his climate model, it seems like it was created for that purpose. There already has been more serious work on the impact of turbines on local (!) windsystems. Global atmospheric circulation is driven by the the arrangement of continents, sea currents, large scale solar insolation, atmospheric composition ... these things. Even mountain ranges have "only" sub-continental impact on gc. With my (limited) knowledge of earth science i'd say: nonsense. Until proven wrong of course :-) Edit: if course, the wind behind the turbine is different than in front of it, but the amount of energy taken out even by a large scale windpark (northsea comes to mind) is neglectible compared to what is available. And polluting the atmosphere with even more greenhouse gases or radiation is the ... second best solution, to say the least ;-)

The IAU gives a definition of a planet or dwarf planet. A moon then is a natural satellite that orbits a planet or dwarf planet. This is a little fuzzy when it comes to bodies of similar size, but as Phoebos and Deimos are Mars' moons likewise Charon is a moon of Pluto. I suppose there is no minimum size, the special case being that two bodies are equal in mass ...

Hi, there have been 2 or 3 threads recently on telescopes. A few people here are doing imaging with telescopes, i'm a beginner myself but reading about it since a few years. Pls., before i go into detail, please specify a little more: you want to do imaging, right ? In principle you can do imaging with any telescope you can look through as long as a few preconditions are met, namely connectivity and mounting. Sadly these preconditions cost funds. What do you want to shoot at ? Rather nebulas/galaxies or planets ? That is a little contradictory because the former needs a wide field and the latter a large magnification. Are you dreaming of a state of the art imaging equipment with a 12cm apochromatic refractor, a decent mount, a ccd cam, a guide scope and guiding cam ? We are talking about many thousand funds then. The telescope itself does not connect, it's the attached equipment (usually a camera) and the mount for guiding (via a guiding camera). On the other hand, the cheapest version for imaging would be a newton reflector with a stable focuser to connect a camera, and an equatorial mount. But even then we are talking >1k funds without camera, the expensice part being the mount. For imaging both refractors and newtons need correcting lenses between the telescope and the camera. In between are the SCT (Schmidt-Cassegrain-Telescopes) in different sizes and fabric. These contain the correction already and have the advantage that the camera can be connected on the axis of the telescope (like a refractor)), which is a far better weight balance compared to the newtons where the equipment sticks out at the side, thus changing the balance over the course of a night while the telescope moves. Also newtons need frequent collimation and take a long time to adjust to the temperature, refractors just work and usually cool down quickly. Don't underestimate weight and balance of an imaging equipment. Usually a mount comes with a number of kilograms (or pounds) it can carry. That is the upper limit, to say the best, stay away from that. So if you have an 8" Newton with 8kg, 1kg camera, 1kg other parts like adaptors and coma-corrector, 3kg guide scope with camera and cable stuff we are in the class of a mount that can carry 20kg .... So, pls. specify a little more. Also, pls. see the forums at www.cloudynights.com, the beginners section has a lot of material to work on :-) And show us your awesome pictures ;-)

Und ich bestelle dann den kleinen Reducer wie von Ihnen vorgeschlagen (siehe unten). Der hat aber kameraseitig nur T2, nicht M48. Für den bräuchte ich eine Anpssung an den 2,5"-Feathertouch-Auszug (also M48 auf M63 ?) sowie am kameraseitigen Ende eine extrem kurzbauende Erweiterung von T2 auf M48, denn ich besitze die TS-Filterschublade für 2" Filter mit M48 auf beiden Seiten sowie den Adapter TSM48-T2. Bitte darauf achten daß sich die Schublade noch öffnen läßt nach Verschraubung ! Ich würde sie freundlich bitten mir vor Versand die weiteren M48-Teile aufzulisten um auf das Maß von 55mm (+1mm für den Filter ?) zu kommen (LZOS 115/805 ist der Refraktor). Sollte das mit M48 nicht aufgehen müssen eben T2-Teile her, dann auch bitte eine Liste der Teile zusenden ______________________ It's German. And it took me 2 hours to figure out (edit: not because it's German ...). I am preparing my christmas present, an order to an astronomy shop. Muy complicado ... i need a focal reducer to connect a camera to a telescope. The telescope has a russian lens in a german crafted tube with an American focuser. Yeah, hail globalisation ! :-) Different threads are involved, luckily even the 'murrican focuser has a metric thread (M63). In the path sits a drawer element for 2" filters and the overall length from reducer-thread to camera chip must be 55mm + thickness of filterglass. 55 is not 54 nor 56. If it works out with M48*1, i ask for a list of parts. If it doesn't, there is a plan B with the slightly smaller T2-thread (M42*0.75). Additional side effects (filter drawer might get locked by thread of screwed-in parts) apply. Be it as it may, i hope to post first-light photos in the astro-photo thread soon(tm). :-)

1/10. I am human. I come in peace.

Totally on your wavelength, @-Velocity-. Unfortunately neither sentience nor intelligence are sharply defined. Anthropologists hedge and stammer when it comes to defining human intelligence. Imho these words are used in every day life to transport a message (intelligent windshield-wipers :-)), to induce a sales message or to distinguish between the one and the other. So, as long as there is no waterproof definition, i think that if we use these words, maybe we have to sketch what we mean to avoid misunderstandings. Edit: i personally for example thought about sentience as something anatomical, nerves as receptors, signal transport, and a brain as a processing unit like "This is hot, hands off !", so limiting sentience to "higher life-forms" like vertebrates .... seems i was wrong ...

You are talking about Nappy Bonaparte (I). There were two others and i always found the III the most interesting of the Napoleons, though Bonaparte 1.0 was the first one to successfully turn Europe in cinder and ashes. At the size of onemeterandsixtyeightcentimeters. We're in Europe, guys ! Continental Europe ! :-)

Might be true that one day we'll dismiss conservation of momentum or find something else to replace it, and maybe the em-drive thing is the first step towards that, but for now and until there haven't been reliable reproductions as well as seriously reviewed papers the em-drive thing is rather something to hope for/believe in. In one of the links in the OP there was a peer reviewed paper announced for december, if i got it right. Looking forward to that ...

@Kokoro: ever tried hdr's in backlight conditions ? The graphical things have their own appeal, no question ... Foehn Wall Video, DSLR, 330 frames, converted to video with ImagesToVideo. Hope the link works ...

Hi, i did a few timelapses and will experiment more. But where to put them ? Youtube just no. I tried vimeo but the upload simply didn't work. Imgur doesn't accept clips (yet ?). Doesn one of you know of any serious hoster for video clips ? I wouldn't like the clips to be put between slippery content ...

He, funny. But it's the thinking of a nineteenth century when things where classified depending on style, make and stratification. Some progress have they made since then. Like physical/chemical dating methods, dating of soil and deposition, flow direction and energy of sediments, the list is looong. It's not that difficult for a professional to date surrounding soil, carved pit, and contents of the pit. You must be very accurate to fool them, like using a material that can't be dated (plastic), spoil and mix the soil with fossil hydrocarbons ... but then your material choice will tell it's own story. Or, in one word: it won't work :-) On the other hand, so much stuff is mixed up in a geological horizon called anthropocene that future archaeology will probably focus on a different approach to field research than how we do it today. Like (science fiction !) applying a strong magnetic field to obtain a direct image of all elements in a cube of earth without digging anything out. Also they'll have their heap of written history, information and disinformation ....

Now on TMT website: http://www.tmt.org/news-center/statement-regarding-selection-alternate-site-tmt Officially announced the primary secondary, alternate, site for the TMT if problems persist on Hawaii. Will report from the construction site if it comes that far ... or near. :-) A local newspaper reported the other day that the committee want a clear go from all involved authorities before they start construction on the Roque de Muchachos. There is a lot of traffic up there, a new visitor center is being built, also sites for astronomy tourists to mount their equipment, away from any lights and nightly aircrafts. Good news: no holy aborigine's sites are up there.

Very rough numbers, depending on circumstances (aircraft, atmosphere), don't nail me to the cross with these numbers: Piston engine uncharged 15.000ft, turbocharged 25.000ft, turboprop 30.000ft, turbofan 35.000ft. Can be more, can be less, but not much ... none of these aircrafts work at the speed of sound. You want a number ? Piston engines (WWII) mach 0.5, Turboprop mach 0.7, turbofans could principally work low supersonic, as said not the airliner ones. A typical Cessna/Piper/Soccata 2-4 seater goes at 80-120knots, a small turboprop 250-350knots, airliners 450, 480 if in a hurry. Legal speed limits apply ;-) No idea about jets ... Aircraft failure at high speeds might not be due to the engine but to the structure ... you know, structural integrity and so on ... :-) If you want specific numbers on a special aircraft (service ceiling, cruising speed), i'm sure you can find them ... each aircraft has a Vne, never exceed speed, a red dial on the airpseed indicator. It's construction is so that above that filght stability and structural integrity can not be guaranteed, like flaps flying off for example or wings saying good-bye to the rest due to high load. Bad things can happen :-)

Looking forward to the paper and following discussion, and of course successfull reproductions ... (pls use si units :-))

Yeah, Soyuz can only reach leo. Ariane 5, are you sure ? It was intended, but is it really ?

Aaah, real science & spaceflight. Feels soooo good :-)

Pizza in space :-) Yeah, even the basis is lacking. There is no launcher rated for human transport and no craft that could transport humans even to the moon. Both are in a state of development, some facing unexpected difficulties. Robotic plants are a challenge even on earth, as are automated vehicles. A lot (billions) is invested by the manufacturers to develop that, they say it's the future and they have the best paid engineers .... I understand you wrote this to show the difficulties (read: impossibility) of such a project. One day soon SpaceX will go to space again.