<?xml version="1.0"?>
<dust version="2.1.5">
<group attachto="milky way">
<particle>
<pos>-2.85065626704077E 22;-2.51860896964597E 22;-1.19278508036318E 22</pos>
<vel>-98669.8089133845;-480087.695355888;-12620.2240438105</vel>
<color>94;112;148</color>
<coloralt>133;202;26</coloralt>
<size>0.464</size>
</particle>
<particle>
<pos>-2.8902737144867E 22;-2.54025408856429E 22;-1.19392810820725E 22</pos>
<vel>-512808.822130403;99191.7691300322;-12617.8796991993</vel>
<color>96;114;152</color>
<coloralt>135;204;26</coloralt>
<size>0.44</size>
</particle>
<particle>
<pos>-2.86712617511411E 22;-2.50668497307232E 22;-1.19279817665385E 22</pos>
<vel>194016.639373354;-638869.257637167;-12638.6466666615</vel>
<color>192;225;247</color>
<coloralt>169;251;39</coloralt>
<size>0.583</size>
</particle>
<particle>
<pos>-2.88798047303789E 22;-2.53319692428078E 22;-1.1946397300561E 22</pos>
<vel>-597051.595799248;97499.886330418;-12627.8554357558</vel>
<color>101;114;159</color>
<coloralt>137;207;26</coloralt>
<size>0.516</size>
</particle>
<particle>
<pos>-2.90963958461226E 22;-2.48129594998068E 22;-1.19379689872708E 22</pos>
<vel>328617.89203342;266568.674172137;-12617.8484732346</vel>
<color>49;63;89</color>
<coloralt>113;172;19</coloralt>
<size>0.644</size>
</particle>
<particle>
<pos>-2.85869849558433E 22;-2.53766212611073E 22;-1.19282200744914E 22</pos>
<vel>-336505.274093228;-338979.101575179;-12617.699802909</vel>
...
Use Blender. 3dstudio max is for capitalists.
look on Artist-friendly particle system tools at wiki.
http://en.wikipedia.org/wiki/Particle_systemBuy Universe Sandbox for the complet system.
Edit:
The solarsystem xml are with mass and other settings.
<?xml version="1.0"?>
<objects version="2.1.5">
<obj>
<AFIAGGPNLBFPKLOPJCGHOLAFIPDMADFLBMIP>false</AFIAGGPNLBFPKLOPJCGHOLAFIPDMADFLBMIP>
<GHCJFOBNPPOIJBDKKCONBCBMLJKMFLCIJFGA>0.3</GHCJFOBNPPOIJBDKKCONBCBMLJKMFLCIJFGA>
<PDIEHMEAEJHADOIAIPMPAJMMIHLNMACDJGKA>0.77</PDIEHMEAEJHADOIAIPMPAJMMIHLNMACDJGKA>
<PKKAGOBBJMLEHEGDCHGDJPLNFOHMOHHMDIPN>0</PKKAGOBBJMLEHEGDCHGDJPLNFOHMOHHMDIPN>
<id>earth</id>
<name>Earth</name>
<mass>5.9736E 24 kg</mass>
<diameter>12742020 m</diameter>
<density>5.5147098661212821</density>
<pos>-118787.629089259;-46625.0433253565;-9090.93460877995</pos>
<vel>-2.53183155610512;-1.10281415374765;-0.202154763952774</vel>
<color>85;101;131</color>
<coloralt>0;0;255</coloralt>
<poslock>false</poslock>
<appearance>Earth</appearance>
<texture>earth.dds</texture>
<rot>0.682607860857802;-0.148518517483756;-0.715597755326294;33.823491588988</rot>
<rotvel>0;0;-0.00417806931416992</rotvel>
<colortint>false</colortint>
</obj>
Another question: How accurate is your CPU?