A Merritt Island, Fla., high school, multiple universities, a handful of non-profit organizations, and several NASA field centers have been selected to fly a series of 24 miniature CubeSat missions in 2014–16. The tiny satellites measure only 4 inches (10 cm) along each face, weigh less than 3 pounds (1.1 kg), have a typical volume of about 1 quart (1 liter), and are mainly composed of commercial, off-the-shelf technology, yet their capacity to be launched rapidly and in groups as auxiliary payloads has made them a force to be reckoned with in recent years.
The recent selections by NASA represent the fourth round of the CubeSat Launch Initiative and will become eligible for flight after final negotiations and mission opportunities become available. Most of the selectees are tertiary academic institutions—including the Embry-Riddle Aeronautical University of Prescott, Ariz., the University of Texas at Austin, the University of Colorado at Boulder, and Vanderbilt University of Nashville, Tenn.—but others are from elsewhere. Merritt Island High School, of Merritt Island, Fla., has partnered with California Polytechnic State University of San Luis Obispo, Calif., whilst The Aerospace Corp. of El Segundo, Calif., and The Discovery Museum and Planetarium of Bridgeport, Conn., have also contributed CubeSat proposals.
Three others originate from NASA’s Jet Propulsion Laboratory (JPL) of Pasadena, Calif. These are the $5.5 million Integrated Solar Array and Reflectarray Antenna (ISARA), which will demonstrate a large, deployable solar array that will pull double duty as a low-cost Ka-band high-gain antenna, in an effort to increase downlink data rates from a baseline 9.6 kilobits per second to more than 100 megabits per second. Launch is expected in 2014. Another is the Interplanetary NanoSpacecraft Pathfinder in Relevant Environment (INSPIRE), which will see the first pair of CubeSats despatched beyond Earth orbit to evaluate functionality, communications, navigation, and payload-hosting technologies. According to NASA, this mission’s fundamental goal “is to open deep-space heliophysics and planetary science to the CubeSat community.” A final JPL mission is the CubeSat VHF Transmitter to Study Ionospheric Dispersion of Radio Pulses (CHIRP) to measure very-high-frequency radio-pulse propagation through the ionosphere.
The idea of miniaturized satellites for a variety of space exploration objectives is not new, and CubeSat as a concept originated in 1999 as a study between a pair of aeronautical and astronautical engineering professors, Jordi Puig-Suari of California Polytechnic State University and Bob Twiggs of Stanford University. They envisaged a capability for graduate students to design, build, test, and operate small, inexpensive, and lightweight satellites in orbit. And for Twiggs, size really did matter. “We use everything we can get,” he told Space.com’s Leonard David in 2004. “If you’ve got lots of room to put everything in, you end up not being too careful with it. That’s the challenge. You’ve got to really think hard when you’re putting together a CubeSat.”
The first half-dozen CubeSats flew from the Plesetsk Cosmodrome, in the taiga wilderness of northern Russia, on 30 June 2003. With an estimated price range of $65,000–$80,000, more than 60 payloads have been launched from sites across the globe (Plesetsk; Baikonur in Kazakhstan; Omelek Island in the Marshall Islands; the Satish Dhawan Space Centre in India; the Uchinoura Space Centre in Japan; and the Guiana Space Centre, near Kourou, French Guiana) and in the United States (Wallops Flight Facility, Va.; Kodiak Launch Complex, Alaska; Vandenberg Air Force Base, Calif.; and Cape Canaveral Air Force Station, Fla.). Numerous boosters have been employed to loft CubeSats, with varying degrees of success or outright failure, including SpaceX’s Falcon 1 and Falcon 9, Japan’s H-II, Europe’s Vega, India’s Polar Satellite Launch Vehicle (PSLV), the U.S. Minotaur, Taurus, and Delta II, and Russia’s Rokot, Kosmos, and Dnepr workhorses.
Standard CubeSats measure 10x10x10 cm and are described as “1U” (or “one-unit”), but are scalable along one axis by 1U increments; in realisation of this capability, “2U” variants, measuring 20x10x10 cm, and “3U” variants, measuring 30x10x10 cm, have also been created and flown. Puig-Suari and Twiggs decided on the basic 10 cm size on the basis that it was large enough to house a basic communications payload, a solar panel, and a battery. This smallness and standardized dimensions—although achieving an “industry standard” was not initially Puig-Suari and Twiggs’ intention—has meant that CubeSats can be carried in a standard deployment mechanism, the Poly-PicoSatellite Orbital Deployer (P-POD), which eject the payload of nanosatellites shortly after arrival in space.
Potential payloads are both practical and exotic in nature. “A CubeSat microsatellite,” wrote Mark Wade on the website Astronautix.com, “could hold anything, from microgravity experiments to the ashes of a loved one.” Moreover, the sheer “internationality” of the CubeSats has been amply demonstrated by the range of sovereign nations whose citizens have, literally, reached for the stars. These payloads have included a Danish digital Earth-imaging camera, a Norwegian amateur radio demonstration, a Japanese satellite tether, a French radiation-monitoring investigation, a Swiss study of the upper atmosphere, a Dutch technology test—including new solar cells and a high-efficiency transceiver—and Colombia’s first satellite, “Libertad-1” (“Freedom-1”). The latter, launched atop a Russian Dnepr rocket in April 2007, was built by the Sergio Arboleda University in Bogotá.
Still, other CubeSat missions have produced the first-ever home-grown satellites for Switzerland, Hungary, Romania, and Poland. Next month, Ecuador’s first satellite will be launched under the banner of the CubeSat program. In December 2010, a handful of CubeSats accompanied SpaceX’s Falcon 9 rocket into orbit, riding piggyback alongside the first solo Dragon demonstration mission from Cape Canaveral Air Force Station, and in October of last year five of the miniaturized satellites were deployed by the Expedition 33 crew of the International Space Station. The latter had been delivered aboard Japan’s Kounotori-3 cargo craft.
With the newly-approved CubeSat missions awaiting their own launch opportunities between 2014 and 2016, there is no lapse in the pace of flights for this year. According to the Ecuadorian Civilian Space Agency, the liftoff of NEE-01 Pegasus is slated for late April, atop a Chinese Long March-2D booster. A second Ecuadorian CubeSat, NEE-02 Krysaor, will follow aboard a Russian Dnepr rocket in June, with others to include a tracking system from Denmark’s University of Aalborg, a solar electric sail from Estonia’s University of Tartu, and an ionospheric experiment from Norway’s University of Oslo. Further downstream, a Finnish meteorological payload and a Planetary Society solar sail have secured tentative spots on the CubeSat manifest.