monophonic

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About monophonic

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  1. monophonic

    New Telescope Tips

    Hi again @HeliosPh0enix, Three weeks have gone by. The moon should now be very well placed for you in the early evening. It is also half moon, or the time of the month when the view will take your breath away, guaranteed. So if you haven't been out again with your telescope now is the time to go.
  2. monophonic

    For Questions That Don't Merit Their Own Thread

    Ultimately this, although not so much directly as because the co-operation between the engineer and the fireman is much easier when both are working in the same space. This co-operation is crucial for most efficient operation of the engine. History of the steam locomotive is long and varied, of course. So there have been a plethora of cab forward and middle designs for various purposes. Some were more successful in their niche than others, but none replaced the traditional setup in general use.
  3. monophonic

    SpaceX Discussion Thread

    These kinds of transports, where signs, lightposts and other fixtures are removed and reattached after the load has passed can and do occur every year over hundreds of kilometers even in a small country such as Finland. They are handled by a handful of smaller companies specializing entirely into these kinds of transports, who are very well connected with the various municipalities, government agencies and utility companies whose infrastructure requires manipulation. They either contract with those parties or get permits to do the necessary changes by themselves. Every such transport is a very thoroughly planned operation and the preparation can take anywhere from several months to a couple of years depending on the load and distance to be travelled. The loads typically move during nights and weekends to minimize disruption to regular traffic. Loads are typically big monolithic industrial equipment such as power substation transformers or biochemical reactor vessels that are difficult to manufacture in place. They can weight up to around 400 tons and be maybe 12 meters wide and tall or 40 meters long. I.e. stuff that is moved once, then sits in one place and provides revenue for many decades. I do not have firm grasp of the costs of such operations, but they must be into millions at least considering how they require many professionals working at night- and weekend rates. And could easily be into tens of millions. Which says this is obviously a no go for an expendable rocket whose launch campaign costs are to be kept as low as possible. Very hard to justify for a limitedly reusable rocket too, such as pre-block 5 Falcon 9. But for BFR... well, as long as the factory and the launch site are both by the sea, a ship is still cheaper and quite possibly faster too.
  4. monophonic

    SpaceX Discussion Thread

    It is always more efficient to use excess capacity in stage two for something than let it burn for nothing in the re-entry. Any bit of payload fuel saved in the plane change and circularization is more fuel available for station keeping. That directly means longer mission life-time - barring any unplanned catastrophic failures of course. So yes, it most likely did some plane changing at the same time as that is only good customer service. Of course it still is up to the payload to finish the job, but it is a slightly easier job.
  5. They are scaling up from New Shepard. It will be impressive if they can manage that without any crashes at first, but I would not consider that totally impossible. Especially since NG is said to be capable of hovering so they can do grasshopper like test flights with the real booster.
  6. monophonic

    Firefly Aerospace Discussion Thread

    Convergent evolution, for a given purpose all designs tend towards a single optimum. On Firefly itself, I remember I tried to build an Alpha analog in KSP 0.22 or thereabouts. A single T800 and aerospike for first stage, a stack of oscar-bs and can't quite remember which tiny engine for second stage. I did not get much further with it because I could not cobble together anything worthwhile (in my mind) for payload.
  7. monophonic

    New Telescope Tips

    Yet your requirements are high enough to imply that an instrument than can verifiably produce a recognizable image of Venus is useless. Do me a favor and tell me how you felt, when starting that first mirror you did, about the posts that said your mirror grinding bench was useless? Also, Dunno where you found the original description, but none of the Amazon listings for the scope I checked mention any erecting optics. Usually those would be mentioned in this price class under the "features" equal "value" marketing principle. They do however mention 10mm and 25mm 1,25" Kellner eyepieces. A cheap Kellner won't max out the image quality from a cheap 80mm achromatic doublet, however a cheap Plössl will and will also be adequate to start with in a better scope later on. Please, guys, if you want to help grow this hobby, don't denigrate stuff that new people already bought. Especially don't denigrate it based on your own factually incorrect prejudices, when the real facts are just a quick google search away. For the fiver the OP paid that scope was a steal.
  8. monophonic

    New Telescope Tips

    Hi again @HeliosPh0enix! What @_Augustus_ said, while rough, is unfortunately quite accurate. Do mind you don't have to upgrade for as long as you yourself are content with it - consider that @_Augustus_ has himself built at least two telescopes from scratch and fully ground the primary mirror for at least one of them! At his level his requirements are magnitudes beyond what I could even take any advantage of over a - several hundred $ - mass market telescope. Take your time, enjoy and don't listen to people who say you can't have fun without X-ton dollar equipment - I know I have ruined many a hobby for me by listening to them. Only upgrade I would recommend for your telescope would be a cheap (and I do emphasize cheap, aim for the $10-$15 price range and "plossl" type) aftermarket eyepiece or two. Anything else will quickly dwarf the retail price of that scope. Still these mass produced eyepieces will be a magnitude better than what came with the scope and will max out the capability of it. They shouldn't be any worse than what comes with a lot more expensive telescopes either, as the manufacturers try to push down on the prices of most popular scopes and make a profit selling better eyepieces and accessories. Another option is to get a good guide and a starmap or planisphere. There is a lot of beautiful sights to see in the sky, but a lot of it can be difficult to find, because there is really a lot of sky up there. These things can help with that. A book named "Turn left at Orion" is often recommended, but I haven't got it personally. A free software called Stellarium is also nice tool to have - but can be a handful to learn especially if you don't know the jargon yet.
  9. monophonic

    New Telescope Tips

    Congrats on picking up a new great hobby! Unfortunately at that price point "a kind of smudgy" is pretty much what you can expect, but don't let that bring you down. Clean all the lenses like @Gargamel suggested and just go check out any targets of opportunity the sky offers you. I will return to you with some suggestions for small upgrades, unless other people beat me to it. You won't need to spend hundreds to get a clear view. In three weeks you should have the moon perfectly placed for you. It is best viewed at half moon anyway when the lighting angle brings out all the details of the surface. One obligatory safety warning though: stay away from those small sun filters that screw into the eyepiece. They have a tendency to crack and let full power of the sun into the eye destroying the sight. All solar observation must be done with a proper full size filter in front of the entire telescope. Or better yet a purpose built solar telescope.
  10. monophonic

    For Questions That Don't Merit Their Own Thread

    Sure. Every boat in it has at least one. But that nearest ship's boat sure is an eyesore. A bright orange RIB on a tall ship, ugh. Certainly very practical as a utility boat though.
  11. monophonic

    For Questions That Don't Merit Their Own Thread

    In this context of orbits around a central body the difference is where the zero point is. Altitude is calculated from the surface of the central body while distance from the center of mass. So a satellite in a geostationary orbit is at altitude of 35,786km above the Earth and distance of 42,164 km from Earth, both at the same time. The difference is the Earth's equatorial radius, 6,378km. All numbers copied from the wikipedia article. https://en.m.wikipedia.org/wiki/Geostationary_orbit
  12. monophonic

    SpaceX Discussion Thread

    A Reliant Robin. Reuseable of course.
  13. A couple notes about the RL-10 choice I found in this article: http://www.spaceflightinsider.com/organizations/orbital-sciences-corp/alpha-omega-orbital-atks-new-rocket-gains-name/ "Affordable" is not a word I would choose. Unless that 3D printing and what else has given some major cost reductions - and / or AJ has cut their margins very low.
  14. monophonic

    Arianespace launch thread

    That biconic thing with solar panels looks like a service module being jettisoned before re-entry rather than a payload to me. Definitely not a fully reuseable system then, but we knew that already from use of the Vega launcher. Perhaps the end-to-end reuseability is meant to only concern the customer's payload? Dunno, I'm not a salesperson.
  15. monophonic

    Arianespace launch thread

    This. This too. Well, either one kinda follows from the other one.