Immediately after breakfast on Monday we split into our two teams and started designing our satellite. Our only guides were the previous week's lectures and our SMAD book, which I had been reading over the weekend. Fortunately, I had taken a course in orbital mechanics last summer, so I had the textbook from that to help us out as well. Some of our first tasks were to narrow down our mission goal and decide on the instruments our satellite would take into space. We thought that it would be best to equip the spacecraft to look for potential dangers on the Moon so that astronauts could avoid them when we land there again. A large part of this would be focused on making a 3D map of the surface of the moon. The tools needed for this job are a laser altimeter and a digital camera. After this team meeting, we split off individually to work on our own subsystems.
Just before lunch, we had to complete a short team-building activity. The goal was this: each team had 10 minutes to plan and 8 minutes to build a tower that was at least 2 meters high and could withstand the program director blowing on it twice. Our materials were a couple of paper plates, some Styrofoam cups, a few big sheets of paper, and tape. Though we came up with a pretty nice design in the first ten minutes, we had nowhere near enough time to complete it, and our final tower looked nothing like our plans. Still, it met the requirements. In fact, our tower was taller than the other team's and, unlike theirs, was able to stand up to both blows and for hours afterward.
After lunch, we were given a very interesting presentation on the history of Moon missions. I was surprised by the number of missions the USSR sent to the Moon. They had sent a number of robotic rovers there much like we are currently doing with Mars. After this presentation, we continued to work in our teams until the end of the day. Even after I got back to my apartment I continued to work. Using the STK software suite, I worked out an efficient orbit for getting to the moon and was then able to visualize our mission, see how well the satellite could observe the moon's surface, and generate some numbers to give to my other team members for their calculations. On the whole, the day was a lot of work, but still it was a lot of fun.
On Tuesday we worked more on our team mission. We decided on a specific Boeing Delta II launch vehicle and on a Star 48 upper stage to put the satellite into its proper orbit. These decisions then gave us a rough estimate on the mass restrictions for our satellite. I also finished up my mission model in STK. This gave us a launch day and time, as well as the required ΔV values to get us to the moon. Using these values, I worked with Robert, our propulsion lead, to determine the fuel requirements. I also used STK to generate a list of times during which our satellite would be in sunlight. These times are important to the Power subsystem, since those were the times during which the satellite can generate power, as well as to the thermal subsystem, since the satellite will be constantly heated during these times.
Our presentation for the day was on NASA's Discovery-class missions. Prior to these missions, NASA typically explored the Solar System with very large and expensive spacecraft, such as the Cassini mission, which cost the US government $3.3 billion. While the science return on these missions is enormous, it is not always enough to justify such a cost to the American public. The Discovery program was established to fund smaller, less expensive missions to explore the Solar System, and it has been extremely successful. I first heard of the Discovery program back in 6th grade, when I attended a summer camp at the Johns Hopkins Applied Physics Laboratory to learn about the very first Discovery spacecraft, NEAR. One of the more unique aspects of all Discovery-class missions is that they are required to allocate from 1-2% of all of their funds to an education and public outreach program, to ensure that the public knows how and why their tax dollars are being spent, and hopefully to excite younger citizens enough to encourage them to work for NASA in the future.
After I got back to my apartment, I began designing this website in order to satisfy the Education and Public Outreach component of our mission. I was hoping to also use the website and a PowerPoint slideshow for our final presentation on Friday, but instead we were to deliver a flip chart presentation all on paper. Still, I continued work on the website, using it to document the progress of our project.
Wednesday involved still more mission design in our teams. In the afternoon, we visited the IMDC again and sat in as they actively worked on the design of the Molniya Imager. It was fascinating to watch as they consulted with each subdivision lead and made trades in order to meet the resource requirements. Their biggest problem was minimizing the mass of the satellite so that they could use a launch vehicle that would fit the monetary budget. Though we were only there for 20 minutes, it was great to see the engineers actually at work, trading and compromising to meet the mission requirements.
After visiting the IMDC, we went to a graduate college fair, sponsored by the National Society of Black Engineers. The speakers at the fair were excellent, but, as we were all freshmen, the fair itself wasn't all that useful. Still, the free food from Subway was nice. Afterwards, most of the members of the program went back to the IMDC to talk to the engineers who had finished their work for the day. Those who went seemed to really benefit from the experience and brought back a lot of knowledge. The rest of us, including me, stayed behind in Building 26 and worked on our subsystems. I worked mostly on the communications subsystem, working out the link budget. I also started documenting our power and mass budgets to help out the systems engineer.
