From: NOSPAMsl AT psycode DOT com (Gili) Newsgroups: gac.physics.astronomy,nctu.club.astronomy,relcom.fido.su.astronomy,tw.bbs.sci.astronomy,comp.os.msdos.djgpp Subject: Orbits, planets, PLEASE HELP! Date: 16 Mar 1998 16:51:07 GMT Organization: Generation.NET Lines: 26 Message-ID: Reply-To: NOSPAMsl AT psycode DOT com NNTP-Posting-Host: portD25.Generation.NET Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8bit To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Precedence: bulk Hello, I have a science project due next week. I am programming something which will find the most efficient orbit given certain parameters. However, I have been unable to find the locations of all planets (and their moons) in our solar system at a fixed time. In order for my program to work, I must have the positions of all planets (and their moons) at a fixed time (so I know where they all begin off) and I also need to know their exact velocity at that given time. My program will launch a rocket into space where it will be totally under the influence of gravity (which is why I need to know the positions/velocities of those planets.) However, I have run into another problem, how do I know the positions of the planets in the solar system after 1 second has past? The same goes for my rocket.. I can resolve the force vectors being applied by all the planets/moons on my rocket, and I know its position and velocity. But where do I go from there? How do I know where it will be a second later? Please help me as soon as possible. Thank you, PS: Please email your response to "sl AT psycode DOT com" Gili