CubeSat

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A CubeSat is a type of miniaturized satellite for space research that usually has a volume of exactly one liter (10 cm cube), weighs no more than one kilogram, and typically uses commercial off-the-shelf electronics components. Beginning in 1999, California Polytechnic State University (CalPoly) and Stanford University developed the CubeSat specifications to help universities worldwide to perform space science and exploration.

Several companies have built CubeSats, including large-satellite-maker Boeing. But academia does most development, with a mixed record of successfully orbited Cubesats and failed missions.

Contents 1 Design 2 Successful projects 3 Applications 3.1 Development of CubeSat technology 3.2 Earth remote sensing 3.3 Space tether 3.4 Biology 3.5 Other 4 Launch failures 4.1 Dnepr rocket crash 4.2 Falcon incident 5 Planned projects 5.1 NASA Educational Launch of Nanosatellites 5.2 QB50 6 See also 7 References 8 External links

[edit] Design

The term "CubeSat" was coined to denote nano-satellites that adhere to the standards described in the CubeSat design specification. CalPoly published the standard in an effort led by aerospace engineering professor Jordi Puig-Suari.^[1] Bob Twiggs, from the Department of Aeronautics & Astronautics at Stanford University, has contributed to the CubeSat community. His efforts have focused on CubeSats from educational institutions.^[2] The specification does not apply to other cube-like nano-satellites such as the NASA "MEPSI" nano-satellite, which is slightly larger than a CubeSat.

In 2004, with their relatively small size, CubeSats could each be made and launched for an estimated $65,000 – $80,000 dollars.^[1] This price tag, far lower than most satellite launches, has made CubeSat a viable option for schools and universities across the world. Because of this, a large number of universities and some companies and government organizations around the world are developing CubeSats — more than 113 in August 2008, Cal Poly reported.

The standard 10×10×10 cm basic CubeSat is often called a "1U" CubeSat meaning one unit. CubeSats are scalable in 1U increments and larger. CubeSats such as a “2U” CubeSat (20×10×10 cm) and a “3U” CubeSat (30×10×10 cm) have been both built and launched.

Since CubeSats are all 10x10 cm (regardless of length) they can all be launched and deployed using a common deployment system. CubeSats are typically launched and deployed from a mechanism called a Poly-PicoSatellite Orbital Deployer (P-POD), also developed and built by CalPoly.^[3] P-PODs are mounted to a launch vehicle and carry CubeSats into orbit and deploy them once the proper signal is received from the launch vehicle. P-PODs have deployed over 90% of all CubeSats launched to date (including un-successful launches), and 100% of all CubeSats launched since 2006. The P-POD Mk III has capacity for three 1U CubeSats, however since three 1U CubeSats are exactly the same size as one 3U CubeSat, and conversely two 1U CubeSats are the same size as one 2U CubeSat; the P-POD can deploy 1U, 2U, or 3U CubeSats in any combination up to a maximum volume of 3U.

Although launch prices have risen^[when?] quite substantially across the board of launch providers,^{[citation needed]} a CubeSat still forms the most cost-effective independent means of getting a payload into orbit. Several companies and research institutes offer regular launch opportunities in clusters of several cubes. ISIS, CalPoly, and UTIAS-SFL offer such services.

Most CubeSats carry one or two scientific instruments as their primary mission payload. A few CubeSat projects have limited propulsion systems; for example, the CubeSat project of the University of Illinois is testing an arcjet thruster that may one day be capable of moving Cubesats both laterally and vertically in their orbits.

[edit] Successful projects

On 27 October 2005, a Kosmos-3M launch vehicle launched from Plesetsk carried three CubeSats into orbit on the SSETI Express mission. The CubeSats on board were projects from the Norwegian University of Science and Technology and the University of Tokyo.

Seven CubeSats were launched April 17, 2007 as secondary payloads on a Dnepr rocket.^[4] They included a Colombian project from the students at the Universidad Sergio Arboleda. Their satellite, called Libertad 1, was Colombia's first. The Aerospace Corporation had their AeroCube 2 and CP-3 & CP-4 were on board from California Polytechnic State University.

In a launch coordinated by the Nanosatellite Launch System, a Polar Satellite Launch Vehicle launched CubeSats on April 28, 2008. One was a 3-unit CubeSat (10x10x30 centimeters) named Delfi-C3 from Delft University of Technology in The Netherlands.^[5]

[edit] Applications

[edit] Development of CubeSat technology

• AAU CubeSat, by Aalborg University - The Danish students in this project, beginning in the summer of 2001, designed a satellite that would evaluate the technology and demonstrate the capabilities of the CubeSat concept. In order to successfully show the technology to the public, the team installed a camera on board the spacecraft, and outfitted it with a magnetically-based attitude control system. But upon reaching orbit, the radio signals were weaker than expected and the batteries failed after only one month of semi-operational activity.^[6]

• PW-Sat, by Warsaw University of Technology - This experiment revolves around CubeSats themselves. The test will involve developing a method to deorbit CubeSats by engaging an atmospheric drag device.^[7] The mission's focus will be the testing of this foil device; its deployment to intentionally bring the satellite back into the thicker portion of Earth's atmosphere to bring the mission to an end.^[8] If successful the satellite will be Poland's first.^[9]

• OUFTI-1, by the University of Liège and I.S.I.L (Haute École de la Province de Liège) - This is a 1-unit CubeSat that is being built by Belgian students. The name is an acronym for Orbital Utility For Telecommunication Innovation. The Belgian satellite is scheduled to launch on the maiden flight of Vega. The goal of the project is to develop experience in the different aspects of satellite design and operation. In the communications portion of the device, the academic team will be experimenting with the D-STAR communications protocol that is popular with amateur radio operators.^[7][10] The satellite weighs just 1 kilogram and will utilize a UHF uplink and a VHF downlink.^[11]

• CubeSat TestBed 1, by Boeing - Boeing successfully completed all of its design and operational goals with its first nanosatellite. It was built and flown to explore the possibilities with the new CubeSat standard.^[12] Boeing satellites are usually much larger; a Boeing 601 or 702 satellite weighs 1,000 times as much as their 10 kilogram CubeSat.^[13]

• InnoSAT, by Atsb - This CubeSat will test attitude control and navigation technologies developed by five Malaysian universities.^[14]

[edit] Earth remote sensing

• Quakesat, by Quakefinder - This satellite was set out on a mission to help scientists improve earthquake detection. The students are hoping that the detection of magnetic signals may have value in showing the onset of an earthquake.^[15] The company that put the satellites together is from Palo Alto, California. They're gathering data on the extremely low magnetic field fluctuations that are associated with earthquakes to help better understand this area of study that has its skeptics.^[16] The 30 June 2003 deployment of Quakesat was along side other university CubeSats and one commercial CubeSat. The launch occurred on a Rockot rocket from Russia’s Plesetsk launch site.

• SwissCube, by École Polytechnique Fédérale de Lausanne - This project has been selected to fly aboard a new expendable launch system being developed for Arianespace jointly by the Italian Space Agency and the European Space Agency. The rocket is called Vega, and takes its name from the star. The Swiss students will conduct experiments with the air glow phenomenon in the Earth's atmosphere.^[7] The satellite's downlink radio will transmit at 437 MHz; the uplink will be at 145 MHz.

• PLUME, by the University of Leicester - They plan to launch a CubeSat that will detect cosmic dust, and will be the first English CubeSat to be launched.^[17] The students began their project at the beginning of 2007 and if successful will have a method for scientists to look at the smallest ever dust particles from space.^[18] They are publishing their documentation and code freely via a wiki.^[19]

• Firefly, by NASA's Goddard Space Flight Center and Siena College - Terrestrial gamma-ray flashes have been detected from the Compton Gamma Ray Observatory after its launch in 1991. Scientists have theories about their origins and this new CubeSat will have instruments that will observe both photons and electrons simultaneously. This, in turn, will allow scientists to better determine if lightning is the source of the gamma ray bursts.^[20]

[edit] Space tether

• MAST, by Tethers Unlimited - The Multi-Application Survivable Tether experiment, based in the United States, was launched 17 April 2007 aboard a Dnepr rocket. This 1 km multistrand, interconnected tether (Hoytether) is being used to test and prove the long-term survivability for tethers in space. The three MAST pico-satellites ejected from the P-POD successfully, but the separation mechanism did not function properly, preventing full deployment of the tether. Nonetheless, the experiment operated for over a month and downloaded over 2 MB of data on tethered satellite dynamics as well as images of the tether.^[21] While Stanford University formed the academic portion of the team, Tethers Unlimited, from Seattle, Washington, formed the commercial portion of the team.^[22]
• Tempo3, by The Mars Society - ^[23]

[edit] Biology

• GeneSat 1, by the NASA Ames Research Center - In December 2006, a Minotaur launch vehicle carried this satellite into orbit from NASA's Wallops Flight Facility to carry out a genetics experiment. The team assembled the biological growth and analysis systems to perform experiments with E coli bacteria.^[24] The project is not cheap by CubeSat standards: the total spent on the satellite and its experiments were $6 million before the launch took place. The goal is to establish methods for studying the genetic changes that come from being exposed to a space environment.^[25] The satellite was outfitted with a UHF beacon.

[edit] Other

• Cubesat ROBUSTA, by Montpellier 2 University - A mission to test the effects of radiation on electronics.^[7] The goal is to specifically check the deterioration of electronic components based on bipolar transistors when exposed to the space radiation environment. The results of this experiment will be used to validate a test method proposed in the laboratory. The French satellite is scheduled to launch on the maiden flight of Vega.
• TJ³Sat, by Thomas Jefferson High School for Science and Technology, Alexandria, Va., which aims to be the first CubeSat by high school students.^[26]
• Xatcobeo, by University of Vigo and Instituto Nacional de Técnica Aeroespacial - The goal for this project is to test software defined radio and to experiment with solar panel deployment.^[7] The Spanish satellite is scheduled to launch on the maiden flight of Vega.
• SADAF SAT, by Pakistan Student Satellite Program - In Pakistan students from several engineering colleges and universities grouped together to start satellite project in 2007. Their planned launch date is in mid of 2011.

[edit] Launch failures

[edit] Dnepr rocket crash

On July 26, 2006, 14 CubeSats from 11 universities and a private company were launched aboard a Dnepr rocket, the largest planned deployment of CubeSats to date.^[2] The rocket failed and was destroyed during launch, obliterating the CubeSats and four other satellites aboard.^[27] The launch was lost after the first stage engine shut down prematurely.^[28] All satellite parts are believed destroyed.

The launch had been postponed numerous times because the primary payload, EgyptSat 1, was not ready. Due to ITAR concerns, the CubeSats were moved to a different launch site, with the primary payload being BelKA, which was to be the first satellite from Belarus.

The launch carried Rincon 1 and SACRED, both from the University of Arizona. Other projects came from the Norwegian University of Science and Technology and Hankuk Aviation University, Seoul, Korea. The Aerospace Corporation, from the United States, also had its own commercial project onboard.

[edit] Falcon incident

On August 3, 2008, a SpaceX Falcon 1 launched from the Kwajalein Atoll launch facility (U.S.) with two NASA Ames CubeSats. They were the PREsat from NASA's Ames Research Center, and the NanoSail-D from both NASA's Marshall Space Flight Center and Ames Research Center.^[29] These CubeSats were lost due to a launch vehicle failure when the rocket's first stage inadvertently made contact with the second stage after separation.

[edit] Planned projects

[edit] NASA Educational Launch of Nanosatellites

A July 2009 was is in place for three university CubeSats to be launched by NASA in their mission called ELaNa (Educational Launch of Nanosatellites). These university satellites include the Space Science and Engineering Laboratory's Explorer-1 PRIME (E1P) developed by students at Montana State University, Kentucky Space's KySat-1 which was developed by multiple Kentucky universities plus several organizations and companies,^[30] and the University of Colorado-Boulder's HERMES. The backup for the launch is University of Florida's ASTREC-1.^[31] The University of Michigan Student Space System Fabrication Laboratory is expected to launch their Cubesat at an unknown date by engineering students at the university. The Inter American University of Puerto Rico (Bayamon Campus) also begun working on a CubeSat and will soon post a launch date.

[edit] QB50

The goal of the QB50 project is to use an international network of 50 CubeSats for multi-point, in-situ measurements in the lower thermosphere (90-300 km) and re-entry research. QB50 is an iniative of the Von Karman Institute, ESA and NASA. Double-unit CubeSats (10x10x20 cm) are foreseen, with one unit (the 'functional' unit) providing the usual satellite functions and the other unit (the 'science' unit) accommodating a set of standardised sensors for lower thermosphere and re-entry research. 35 CubeSats are envisaged to be provided by universities in 19 European countries, 10 by universities in the US, 2 by universities in Canada and 3 by Japanese universities. All 50 CubeSats will be launched together on a single launch vehicle, a Russian Shtil-2.1. The launch is planned for mid 2013. ^[32]

[edit] See also

• AMSAT
• Canadian Advanced Nanospace eXperiment Program
• Israeli Nano Satellite Association
• OSCAR
• UCISAT

[edit] References

[edit] External links

• CubeSat Program official website Contains information about upcoming launches.
• Extensive list of Cubesat missions
• Amsat's list of CubeSats Generally kept well up to date
• Ralph Wallio's CubeSat Information Page Up to date with current Keplerian elements and frequency information.
• CubeSat Design Specification