With advances in nanotechnology, very small-scale satellites, known as femtosatellites, which weigh less than 100 grams (i.e., less than 0.22 lbs) have been developed over the last fifteen years. Most of these small satellites have been used with “mother” satellites that provide operating signals; however, more recent versions are operating independently.
In 2013, Peru had made history by launching a femtosatellite into low Earth orbit. What that demonstrated is that countries that have traditionally been priced out of the satellite making and deployment market could now begin to compete by utilizing much cheaper satellite systems that can provide a variety of signaling capability. The design was by the Ponftificia Universidad Catolica del Peru by the Institute for Radio Astronomy and was called Pocket-PUCP, where that satellite transmitted temperature data.
One well known femtosatellite program was KickSat, which launched in 2014. It was designed to carry hundreds or thousands of smaller satellites that were called sprites that were essentially microchips. The mission was crowdfunded and focused on sending radio signals from the large network of sprites that would be released, demonstrating the effectiveness of the satellite systems in creating a network of low Earth orbit monitoring. Although the satellite system burned up in reentry in 2014, the structure of funding and use of smaller, microchip-sized satellites did create a template that future projects have since followed.
One advanced type of femtosatellite developed by Arizona State University scientist is called SunCube. The satellite is only 3 cm across and wide and costs about $1000 to launch from an orbiting Earth station, like the International Space Station, or about $3000 to put into low Earth orbit. Conventional satellite launches could now cost about $60,000, but with SunCube the cost for a normal orbit launch could be around $27,000. This now puts satellite launches within budgets for university-run research projects or small laboratories.
Using Femtosatellites for Earth Observation
The focus areas of femtosatellites are taking space pictures, test future technology, land on asteroids, and conduct biology experiments. The idea of SunCube and other similar systems is to now focus on Earth and near Earth satellite monitoring, including monitoring current and future space stations. It has been suggested that privatized launch companies may begin to reorient their strategic focus towards small-scale satellite systems.
Challenges for Deploying Femtosatellites
One challenge for femtosatellites is as they move outside of low Earth orbit and into medium and beyond ranges, determining their positioning becomes more difficult. This is because signaling capability is limited by the size of the systems. Kalman filtering techniques applied to Doppler shift measurements from satellites have been used to track and determine locations for satellites at more distant orbits. This shows that even with limited signaling capacity, the satellites could still be tracked and, therefore, positioned to provide potential observation data.
Femtosatellites and other types of small satellites are beginning to revolutionize not only who can send satellite systems in space but they have now given unprecedented access for data collection. One challenge might be, similar to unmanned aerial vehicles, is on how this emerging market and research area could be regulated, as the trouble of space debris continues to be a long-term problem that femtosatellites, particularly as hundreds or thousands can be launched at one time, could add to. International regulations are beginning to attempt to limit the amount of space debris, but with small satellite systems now potentially operational by individuals, how effective regulations will be can be an open question. Nevertheless, the long-term benefits also suggest that more varied types of monitoring data can be more easily created and developed and also, potentially in the near future, deployed to more distant orbits without even the need for having mother satellites.
 For more on the launch of a femtosatellite by Peru, see: http://smallwarsjournal.com/jrnl/art/a-small-box-that%E2%80%99s-a-big-deal-how-latin-american-countries-are-using-cubesats-and-why-it-ma
 For more on KickSat, see: https://digitalcommons.usu.edu/smallsat/2013/all2013/111/
 For specifications on SunCube, see: http://femtosat.asu.edu/suncube_femtosat_design_specifications_v1.pdf
4 For more on low cost femtosatellites, see: Barnhart, D.J., Vladimirova, T., Baker, A.M. & Sweeting, M.N. (2009) A low-cost femtosatellite to enable distributed space missions. Acta Astronautica. [Online] 64 (11–12), 1123–1143. Available from: doi:10.1016/j.actaastro.2009.01.025.
 For more on the cost of femtosatellites, see: McGrath, Ciara and Kerr, Emma and Macdonald, Malcolm (2015) An analytical low-cost deployment strategy for satellite constellations. In: 13th Reinventing Space Conference, 2015-11-09 – 2015-11-12 & Barnhart, D.J., Vladimirova, T., Baker, A.M. & Sweeting, M.N. (2009) A low-cost femtosatellite to enable distributed space missions. Acta Astronautica. [Online] 64 (11–12), 1123–1143. Available from: doi:10.1016/j.actaastro.2009.01.025.
 For more on what aspects femtosatellites could be developed for, see: Lastovicka-Medin, G. (2016) Nano/pico/femto-satellites: Review of challenges in space education and science integration towards disruptive technology. In: [Online]. June 2016 IEEE. pp. 357–362. Available from: doi:10.1109/MECO.2016.7525781 [Accessed: 20 November 2017].
 For more on techniques to allow the tracking of femtosatellites outside of low Earth orbit, see: Oh, H., Park, H.-E., Lee, K., Park, S.-Y., et al. (2016) Improved GPS-based Satellite Relative Navigation Using Femtosecond Laser Relative Distance Measurements. Journal of Astronomy and Space Sciences. [Online] 33 (1), 45–54.