![]() Sometimes, when zooming in on a comet or asteroid, both the 3D textured spheroid and the star-like fuzzy blob are visible at the same time, and the star texture is “dancing around” the “solid” spheroid.Despite the fact that both use “absolute magnitude” and “slope parameter” as parameters, apparent magnitude is calculated in different ways for comets and asteroids. (It is also used with some of Stellarium’s default Solar System bodies when there’s no available surface map of the body, for example for some of the gas giants’ satellites.)Īll comets imported via the plug-in get the same radius – 5 km (see lines 518 and 969 in SolarSystemEditor.cpp).Īll asteroids imported via the plug-in have their approximate size calculated from their absolute magnitude with an assumed albedo of 0.15 (see line 737 in SolarSystemEditor.cpp).įor both asteroids and comets imported with the plug-in, the apparent magnitude (brightness) is calculated using simplistic two-parameter models that provide only a crude approximation. In both cases, the provided information contains only the object name and/or designation, its current orbital elements and data for predicting its brightness.Īll comets and asteroids imported via the Solar System Editor plug-in use the same surface texture – nomap.png. ![]() They maintain both prepared lists of interesting objects and a search engine, hence the two tabs in the “Import data” window – “Lists” and “Online search”. When you import new bodies with the Solar System Editor plug-in, you pull the information from the website of the Minor Planet Center. The situation is the same with asteroids – they are rendered as balls, instead of irregular lumps. Realistic rendering of comets has been on the wishlist for quite some time now, but no willing OpenGL programmer has stepped forward to do something about it. ![]() Instead, they look just like the other Solar System objects – star-like if you are zoomed out, textured balls when you zoom in enough. Stellarium doesn’t render comets realistically – it can’t display they tail and coma. The size of the fuzzy blobs can be manipulated using the “Absolute scale” and “Relative scale” parameters in the “Sky” tab of the “Sky and viewing options” window. apparent magnitude), not the size of the body itself. When Solar System objects are rendered as star-like objects (fuzzy blobs), they are treated as stars – their apparent size reflects their current brightness (i.e. How a particular body is rendered in any given moment depends on its size and the current FOV/zoom/magnification – when the view is “zoomed out” enough, the object is rendered as a star. The one in your user directory overrides the one in Stellarium’s installation directory.) Indeed, before the introduction of the Solar System Editor plug-in, manually editing that file was the only way to add Solar System objects to Stellarium.Īll Solar System objects can be rendered in two ways – as star-like objects with a fuzzy halo and as spheroids wrapped in a texture (an image showing the surface of the body). ![]() It’s a plain text file, so you can open it with something like Notepad++ and look at what data Stellarium is using for a given object. Stellarium’s database of Solar System objects is kept in the ssystem.ini file. This applies to stars, Solar System objects, nebulae, satellites, etc. It can’t display an object that is not in its databases, and its databases don’t contain all objects that exist or even all that are known. Some parts of the description may no longer apply to future versions.įirst, let’s make something extremely clear. I’m going to discuss the videos themselves after the explanation.Īll of this applies to Stellarium 0.11.0, released in July 2011. A recent example is a series of videos on YouTube that convinced me that I need to explain how Stellarium handles comets and asteroids and how the Solar System Editor plug-in works. Some of the stuff I come upon during these vanity searches is rather amusing, though. It’s also a good way to catch bugs that haven’t been reported to Stellarium’s bug tracker. It’s a good way to find out what good (or bad) things software reviewers are saying about Stellarium (and sometimes about me). I occasionally search for Stellarium in Google when I’m bored.
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