Right now, there are many groups of people either planning, designing, making or launching small cube-based satellites in order to push the boundaries of spaceflight and space missions.
Cubesats, which are satellites consisting of 10cm x 10xm x 10cm units (or 1U) are very popular amongst all kinds of players in the space industry. From the university projects and small businesses to the grand agencies, including NASA. The satellites themselves are a mixture of simplicity, common-sense design practice and are often very cheap (thousands of dollars/pounds rather than 100’s of thousands).
They are standardised modules of fixed sizes with standardised launch mechanisms, often consisting mostly of off-the-shelf components rather than bespoke and unique payloads.
Cubesats versus Conventional
The main difference between a cubesat and a conventional satellite is size. Cubesats are in volume terms at 2 or 3 orders of magnitude smaller. So for launch mass and associated costs (typically estimated at $10,000 to $20,000 per kg) cubesats present a real advantage.
Another difference is the development cost. Because cubesats were created to be a low-cost way of getting into space, tight requirements meant that off-the-shelf parts and standardisation became the only way to ensure quick turnaround times. Having less time often translates to less management and overhead costs as well as a drive to achieve results and deliveries. In other words, Parkinson’s Law applies.
Some of the advantages with conventional satellites are that communication does not have to be limited and there can often be greater margin with payloads, provided some optimisation of the system has been used (for example, chemical propulsion versus electric). Power is another factor with cubesats typically being a few W or tens of W compared to kW for larger satellites.
Common barriers to easy launch
On the surface, cubesats represent affordable space technology solutions, at least in the design and manufacture of the satellites themselves. The barrier, however, is still easy access to space, either in getting onto a mission, or dealing with the associated licencing and launch site costs. These can sometimes eclipse the price of your satellite.
One other common cost is propellant wastage when a launch is delayed on site. For larger rockets, which may contain a small cubesat payload, propellant costs can be up to $500,000.
Taking a different route there is also the bureaucratic barrier, as touched on before. One issue with cubesats is that they have to be a complete system in one, or at least have a basic functionality where they have they have standalone power, communication and payload. At times this means no propulsion, which has led to calls for propulsion to be mandatory as otherwise the satellites are inherently space debris.
Recently, it was deemed that 1 in 5 cubesats violated disposal guidelines. If there is a crackdown on proliferation of all types of small satellites the associated program costs could cause the industry to go into remission.
Possible benefits of Cubesats beyond basic use
Already there are plans to use cubesats in more ways than just be technology demonstrators or simple science missions. Planet Labs are putting together a constellation of satellites to view the Earth and with Nanoracks launched a 28-satellite constellation called Flock 1.
However, what if you want docking satellites or close formation flying satellites? Tyvak Nano-Satellites Systems and NASA are working on a mission called CPOD (Close Proximity Operations Demonstration) in which satellites will fly together and also demonstrate docking.
CPOD mission from NASA.
The potential for constructing larger satellites out of component sats, in a small way reminiscent of the Constructicons from Transformers. Satellites that build to create larger satellites but do so at a fraction of the price of one very large satellite? That could present a powerful change in the space industry and is a direction that Corvos Astro Engineering is interesting in taking.