I am dissapoint. This software isn't very scientific! :(

[ds7202]

I must say, on the surface, this software seems like an awesome piece of work!  You can create your own "universe!" What's better than that?

Well, I am somewhat disappointed in this.  I tried using this software to model orbits from problems in BM&W*.  I ran into several problems:

First off, it seems that mass cannot be negated- I can't model orbits of particles, based solely on classical orbital parameters.  However, I give credit to the fact that you can create your own orbit using the classical set of parameters:  however, instead of using the TRUE ANOMALY (which BM&W uses), it asks for MEAN anomaly.  Why did the programmers decide on this?  M and Nu are the same if it's a circular orbit, but not if the orbit is elliptical!  (this is why astrodynamicists mostly use true anomally in the classical parameters rather than mean anomaly.)

Also, i'm kind of miffed that these aren't represented by their symbols in the software (For instance, parameters are classically listed in the form of:

 (a or p, e, i, Ω, ω; ν0)

where a is semimajor axis and p is semi-latus rectum,
e is eccentricity,
i is inclination angle,
Ω is longitude of ascending node,
ω is argument of periapsis,
ν0 is true anomaly.

It would be a lot easier to model REAL orbits if the parameter ν0 was used in the software rather than M (mean anomaly.) (then we don't have to use kepler's equations to solve for M O_o)


Oh, also, the camera is really wonky.



*BM&W refers to Bate, Mueller, and White's Fundamentals of Astrodynamics (pretty much the bible of orbital mechanics)

[Darvince]

So just because of the anomaly it's very non-scientific?

[APODman]

First off, it seems that mass cannot be negated- I can't model orbits of particles, based solely on classical orbital parameters.

But it´s possible to create orbits with massless particles in Universe Sandbox, and the true anomaly are not absolutely necessary. Even in another simpletic integrators ( like Mercury, Solsyin, ORSA, etc ) you use Mean Anomaly instead True Anomaly.

If you wants more control and accuracy work directly in the XML file of the simulation, there you can use also vetorial data.


[ ]´s

[dhm794]

It's not an exact replica of the universe as we know it.  It's intended to be scientific, but not 100% accurate.