CrowdSat

The second question comes from Heriberto from the SEDS chapter at Instituto Tecnologico y de Estudios Superiores de Monterrey (ITESM) in Mexico. Apparently he and his friends are starting a CubeSat program at his university -- great to hear.

Question 2: Can we choose our working orbit or do we have to follow an established orbit?

Since there are so few CubeSat launches available each year -- if there even is a launch available in a given year -- you are likely stuck with any orbit that you can get. CubeSats are launched as secondary payloads, meaning that they are placed in a similar orbit to the primary payload; this is how the launch cost for a CubeSat can be so "inexpensive" (if you can call ~$50,000 inexpensive, but you take what you can get).

Looking at the CubeSat Community Website, there have been six CubeSat launches:

1. 30 June 2003. Six CubeSats were launched aboard a Rockot rocket from Russia. The primary payload was the Canadian Space Agency's Microvariability and Oscillations of STars (MOST). The CubeSats were placed in a circular sunsynchronous orbit with an altitude of 820 km.
   
2. 27 October 2005. Three CubeSats were launched aboard a Kosmos-3M rocket from Russia. The primary payload was SSETI Express. The CubeSats were placed in a 686 km circular orbit at an inclination of 98 degrees.
   
3. 21 February 2006. One CubeSat was launched aboard an M-V-8 rocket from Japan. The primary payload was JAXA's ASTRO-F satellite. The CubeSat was placed in a sunsynchronous polar orbit with an apogee of 751 km and a perigee of 290 km at an inclination of 98 degrees.
   
4. 26 July 2006. Fourteen CubeSats were launched aboard a Dnepr rocket from Kazakhstan. However, the rocket failed to reach orbit. The intended orbit was a 500-600 km circular sunsychronous orbit at an inclination of 97.43 degrees.
   
5. 11 December 2006. One CubeSat was launched aboard a Minotaur rocket from the United States. The primary payload was TacSat-2. The CubeSat was placed in a circular orbit with an altitude of 410 km and an inclination of 40 degrees.
   
6. 17 April 2007. Seven CubeSats were launched aboard a Dnepr rocket from Kazakhstan. The primary payload was EgyptSat 1. The CubeSats were placed in an approximately circular 700 km orbit at an inclination of 98 degrees.

That's the basic information from the CubeSat launch history. Launches for a CubeSat are quite rare, so if you do find a rocket that is willing to host your satellite, go for it. If you wait for a perfect orbit, you may be waiting for a long time.

Does this information help?

(ps: I'll post sources and more precise orbital parameters as I find them...)