A CubeSat is a class of small satellite with a form factor of 10 cm (3.9 in) cubes. CubeSats have a mass of no more than 2 kg (4.4 lb) per unit, and often use commercial off-the-shelf (COTS) components for their electronics and structure. CubeSats are deployed into orbit from the International Space Station, or launched as secondary payloads on a launch vehicle. As of December 2023, more than 2,300 CubeSats have been launched.
Ultra low frequency (ULF) is the ITU designation for the frequency range of electromagnetic waves between 300 hertz and 3 kilohertz, corresponding to wavelengths between 1,000 to 100 km. In magnetosphere science and seismology, alternative definitions are usually given, including ranges from 1 mHz to 100 Hz, 1 mHz to 1 Hz, and 10 mHz to 10 Hz.
A small satellite, miniaturized satellite, or smallsat is a satellite of low mass and size, usually under 1,200 kg (2,600 lb). While all such satellites can be referred to as "small", different classifications are used to categorize them based on mass. Satellites can be built small to reduce the large economic cost of launch vehicles and the costs associated with construction. Miniature satellites, especially in large numbers, may be more useful than fewer, larger ones for some purposes – for example, gathering of scientific data and radio relay. Technical challenges in the construction of small satellites may include the lack of sufficient power storage or of room for a propulsion system.
A star tracker is an optical device that measures the positions of stars using photocells or a camera. As the positions of many stars have been measured by astronomers to a high degree of accuracy, a star tracker on a satellite or spacecraft may be used to determine the orientation of the spacecraft with respect to the stars. In order to do this, the star tracker must obtain an image of the stars, measure their apparent position in the reference frame of the spacecraft, and identify the stars so their position can be compared with their known absolute position from a star catalog. A star tracker may include a processor to identify stars by comparing the pattern of observed stars with the known pattern of stars in the sky.
Explorer-1 [Prime], also known as E1P and Electra, was a CubeSat-class picosatellite built by the Space Science and Engineering Laboratory (SSEL) at Montana State University. It was launched aboard a Taurus-XL rocket from Vandenberg Air Force Base, California on 4 March 2011, but failed to achieve orbit after the rocket malfunctioned.
HawkSat-1 was a single-unit CubeSat which was built and is being operated by the Hawk Institute for Space Sciences (HISS), Pocomoke City, Maryland. It is based on a Pumpkin Inc. CubeSat kit, and carries a technology demonstration payload, primarily as a proof of concept mission, testing command, data and power subsystems, as well as solar panels and communications.
QuakeFinder is a company focused on developing a system for earthquake prediction. QuakeFinder operates as a project of aerospace engineering firm Stellar Solutions, and by subscriptions and sponsorships from the public.
Seismo-electromagnetics are various electro-magnetic phenomena believed to be generated by tectonic forces acting on the Earth's crust, and possibly associated with seismic activity such as earthquakes and volcanoes. Study of these has been prompted by the prospect they might be generated by the increased stress leading up to an earthquake, and might thereby provide a basis for short-term earthquake prediction. However, despite many studies, no form of seismo-electromagnetics has been shown to be effective for earthquake prediction. A key problem is that earthquakes themselves produce relatively weak electromagnetic phenomena, and the effects from any precursory phenomena are likely to be too weak to measure. Close monitoring of the Parkfield earthquake revealed no significant pre-seismic electromagnetic effects. However, some researchers remain optimistic, and searches for seismo-electromagnetic earthquake precursors continue.
Radio Aurora Explorer (RAX) is the first National Science Foundation sponsored CubeSat mission. The RAX mission is a joint effort between SRI International in Menlo Park, California and the University of Michigan in Ann Arbor, Michigan. The chief scientist at SRI International, Dr. Hasan Bahcivan, led his team at SRI to develop the payload while the chief engineer, Dr. James Cutler, led a team of students to develop the satellite bus in the Michigan Exploration Laboratory. There are currently two satellites in the RAX mission.
NanoSail-D2 was a small satellite built by NASA's Marshall Space Flight Center and Ames Research Center to study the deployment of a solar sail in space. It was a three-unit CubeSat, measuring 30 cm × 10 cm × 10 cm with a mass of 4 kg (8.8 lb). Its solar sail had an area of 10 m2 (110 sq ft), and was deployed in around five seconds.
KickSat was a satellite dispenser for small-satellite (femtosatellite) project inaugurated in early October 2011, to launch many very small satellites from a 3U CubeSat. The satellites have been characterized as being the size of a large postage stamp. and also as "cracker size". The mission launch was originally scheduled for late 2013 and was launched April 18, 2014.
RAX-2 is a CubeSat satellite built as a collaboration between SRI International and students at the University of Michigan College of Engineering. It is the second spacecraft in the RAX mission. The RAX-1 mission ended after approximately two months of operation due to a gradual degradation of the solar panels that ultimately resulted in a loss of power. RAX team members applied the lessons learned from RAX-1 to the design of a second flight unit, RAX-2, which performs the same mission concept of RAX-1 with improved bus performance and additional operational modes. Science measurements are enhanced through interactive experiments with high power ionospheric heaters where FAI will be generated on demand.
The Dynamic Ionosphere CubeSat Experiment (DICE) is a scientific mission consisting of two Miniaturized Satellites DICE-1 and DICE-2 flying in formation. The satellites are an unusual 1.5U variant of the CubeSat design for microsatellites. Both satellites were launched from Vandenberg Air Force Base in October 2011 atop a Delta II rocket. This was a multi-payload mission with four other CubeSats, AubieSat-1, M-Cubed, Explorer-1_Prime and RAX-2.
Technology Education Satellite (TechEdSat) is a successful nano-sat flight series conducted from the NASA Ames Research Center in collaboration with numerous universities. While one of the principal aims has been to introduce young professionals and university students to the practical realm of developing space flight hardware, considerable innovations have been introduced. In addition, this evolving flight platform has tested concepts for Low Earth Orbit (LEO) sample return, as well as planetary nano-sat class mission concepts.
STRaND-1 is a failed 3U CubeSat developed by Surrey University's Surrey Space Centre (SSC) and Surrey Satellite Technology (SSTL). The 4.3 kg (9.5 lb) nanosatellite was launched into orbit on board a PSLV Rocket from India on February 25, 2013, Smartphones have flown in space before inside the International Space Station, and the computer from a PDA launched inside two Japanese CubeSats in 2006 and 2008.
AAUSat-3, is the third CubeSat built and operated by students from the Aalborg University in Denmark. It was launched on 25 February 2013 from the Satish Dhawan Space Centre in India on a Polar Satellite Launch Vehicle (PSLV) launch vehicle (PSLV-C20). AAUSat-3 carries two Automatic Identification System receivers as the main payload.
ASTERIA was a miniaturized space telescope technology demonstration and opportunistic science mission to conduct astrophysical measurements using a CubeSat. It was designed in collaboration between the Massachusetts Institute of Technology (MIT) and NASA's Jet Propulsion Laboratory. ASTERIA was the first JPL-built CubeSat to have been successfully operated in space. Originally envisioned as a project for training early career scientists and engineers, ASTERIA's technical goal was to achieve arcsecond-level line-of-sight pointing error and highly stable focal plane temperature control. These technologies are important for precision photometry, i.e., the measurement of stellar brightness over time. Precision photometry, in turn, provides a way to study stellar activity, transiting exoplanets, and other astrophysical phenomena.
CubeSail was a 2018 low-cost spacecraft propulsion demonstration mission using two identical 1.5U CubeSat satellites to deploy a 260 m (850 ft) long, 20 m2 (220 sq ft) solar sail ribbon between them. This mission was a first in a series of increasingly-complex planned demonstrations leading up to a full-scale UltraSail heliogyro by the University of Illinois and CU Aerospace.
Bi-sat Observations of the Lunar Atmosphere above Swirls (BOLAS) is a spacecraft mission concept that would orbit the Moon at very low altitude in order to study the lunar surface. The concept, currently under study by NASA, involves two small identical CubeSat satellites connected vertically above the lunar surface by a 25 km long tether. The mission goal would be to understand the hydrogen cycle on the Moon, dust weathering, and the formation of lunar swirls.
