Ask Slashdot: How Would You Build a Microsatellite?

Having been on a team that has built and launched two cubesats, I consider myself somewhat of an expert in the area. I'll answer this question to the best of my knowledge, I've been to the cubesat conference for several years now (it's mostly academics but most of the launch companies are there.) The first couple of years as a student I would get all excited whenever companies like this would start up. I noticed quickly that the same company never came around to the conference more than a few years, why? Because they couldn't get the funding, a launch requires some where in the range of 10$ million. There are plenty of companies that start up and claim that they will launch a rocket with a 50-100 (or so cubesats) and that will cover there costs, the problem is they have to find that many people to fill the spots. No one has done that yet. Cubesats were designed as a containerized system to mitigate the testing and integration launch costs. Everything that goes to space has to be thoroughly tested, when you have to do this on a case by case basis, it takes a lot of time (=money). So if you already know your payload will fit in a 10cm x 10cm x 10cm (1U) and has a ~1kg weight then that saves a lot of testing. Another benefit of the container is NASA can slap them all over their rockets and launch 10's of them (currently) at a time. Since every rocket has tons of payload margin (you want to ensure your payload reaches space you size its mass several percent smaller than what the rocket can handle to ensure delivery) and some payloads are in the tons, throwing on a few cubsats won't really do a thing to your mass budget. Now NASA has a program for this: http://www.nasa.gov/mission_pages/smallsats/elana/index.html [nasa.gov] this has been successful. As far as launching your own, I wouldn't count on it in the near future. Launching a satellite is not trivial, you have to make sure its not going to break apart, or damage other payloads on the way out of its container. Look up ISBN: 047075012X . You have to make sure its not going to outgass because volatile compounds evaporate and can cause problems. You have to use materials that can withstand the rigors of space, atomic oxygen and radiation can be rough on most materials. Plus some materials like PVC will evaporate in a vacuum. Another problem is ensuring you have enough battery and solar power to support your payload. You have to make sure you payload will not shake apart on the way up (rockets are very very bumpy rides). The satellite should have an attributed and control system to make sure it can orient itself in the right direction (for your solar cells and radio). And last but not least is the radio and comm system. A ground station is needed and the appropriate radio frequencies used (if you want anything fast you have to get a license from the gov, this is very difficult). The satellite itself needs to have a good antenna (if you have any nulls in your antenna pattern then you won't be able to communicate with it when the null is pointed at you. Oh, and if you put a camera on it the NOAA has to know about it and approve of your data (really stupid, but that's the way the government is). Anyway I could go on for a long time... Building a satellite requires people from many different disciplines to pull it off. Unless you are going for insanely simple you would have to have a group of people to accomplish the task. If there is available access and launch costs come down I could see a few hobbyists groups pulling it off in 10 or so years if they can clear all of the governmental hoops. I won't believe any commercial venture claiming that they will launch cubesats (or tubesats http://interorbital.com/TubeSat_1.htm [interorbital.com]) until they actually do.

Source: http://rss.slashdot.org/~r/Slashdot/slashdotScience/~3/Sc8VAdp2KEA/story01.htm

Dana Vollmer phillies phillies Ryan Dempster Phelps NBC Olympics Live Olympic medal count