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Certain repeating sequences of DNA are also called Microsatellites. See [[Wikipedia:Microsatellite (genetics)]]<br>

'''Miniaturized satellites''' or '''small satellites''' are [[Wikipedia:artificial satellite|artificial satellite]]s of unusually low weights and small sizes, usually under 500 [[Wikipedia:kilograms|kilograms]].<ref>{{cite web|url= http://centaur.sstl.co.uk/SSHP/sshp_classify.html |title= Satellite Classification |accessdate=2010-06-04}}</ref> While all such satellites can be referred to as ''small satellites'', different classifications are used to categorize them based on mass (see below).

One reason for miniaturizing satellites is to reduce the cost: heavier satellites require larger rockets of greater cost to finance; smaller and lighter satellites require smaller and cheaper launch vehicles and can sometimes be launched in multiples. They can also be launched 'piggyback', using excess capacity on larger launch vehicles. Miniaturized satellites allow for cheaper designs as well as ease of mass production, although few satellites of any size other than 'communications constellations' where dozens of satellites are used to cover the globe, have been mass produced in practice.

Besides the cost issue, the main rationale for the use of miniaturized satellites is the opportunity to enable missions that a larger satellite could not accomplish, such as:
* Constellations for low data rate communications
* Using formations to gather data from multiple points
* In-orbit inspection of larger satellites.
''This article contains content from Wikipedia. Parts of it [http://en.wikipedia.org/wiki/Wikipedia:Articles_for_deletion/COMMStellation were deleted from Wikipedia]''

==The Physics Behind Covering the Earth==

Polar oriented, or [[Wikipedia:Polar orbit|Polar orbiting]] microsatellites pass approximately over the north and south poles along lines of [[longitude]]<ref>[http://www.newmediastudio.org/DataDiscovery/Hurr_ED_Center/Satellites_and_Sensors/Polar_Orbits/Polar_Orbits.html Polar Orbiting Environmental Satellites (POES)]</ref>. Imagine shining a flashlight on a globe at a simulated 1,000 km above the earth surface. The [[diameter]] of the beam on the earth will cover 4,819 km assuming a 10 degree slant angle<ref>[http://www.1728.com/volcone.htm Right Circular Cone Calculator & Cone Frustum Calculator]</ref>. If you were to draw a [[square]] within that footprint such that each corner of the square just touches the edge of the [[circle]], each side of the square will have a length of 3,407 km<ref>[http://mathcentral.uregina.ca/QQ/database/QQ.09.04/bob1.html Math Central, Pythagorean Theorem]</ref>. With the 12 spaces (found between the six orbital planes) [[multiplied]] by 3,407 km, the coverage of the squares equals 40,884 km. The circumference of the earth at the [[equator]] is approximately 40,075 km<ref>[http://geography.about.com/library/faq/blqzcircumference.htm What is the circumference of the earth?, About.com]</ref>. As such, the squares will overlap each other at the equator providing complete coverage. As you move toward the poles, the circumference of the earthâ€™s east/west orientation decreases as the cosine of the latitude <ref>[http://www.newton.dep.anl.gov/askasci/env99/env086.htm Environmental Earth Science Archive, Department of Energy, United States of America]</ref> resulting in more overlap. In addition, if we include the area between any side of the square and the edge of the circle, the overlap from one satellite footprint to another is greater. The overlap at the equator covers an area of approximately 1,480 km. The strength of the beam at the surface varies with the square of the satellite altitude according to the inverse-square law.

==Classification groups==
[[Image:Space Technology 5 on payload structure.jpg|thumb|300px|3 microsatellites of [[Space Technology 5]]]]
=== Minisatellite ===
The term "minisatellite" usually refers to an artificial satellite with a "wet mass" (including fuel) between 100 and 500 kilograms (kg), though these are usually simply called "small satellites". Minisatellites are usually simpler but use the same technologies as larger satellites.

=== Microsatellite ===

Microsatellite or "microsat" is usually applied to the name of an artificial satellite with a wet mass between 10 and 100 kg. However, this is not an official convention and sometimes microsats can refer to satellites larger than that. Sometimes designs or proposed designs of these types have microsatellites working together or in a formation. The generic term "small satellite" is also sometimes used.

=== Nanosatellite ===
The term "nanosatellite" or "nanosat" is usually applied to the name of an artificial satellite with a wet mass between 1 and 10 kg. Again designs and proposed designs of these types usually have multiple nanosatellites working together or in formation (sometimes the term "swarm" is applied). Some designs require a larger "mother" satellite for communication with ground controllers or for launching and docking with nanosatellites.

=== Picosatellite ===
Picosatellite or "picosat" (not to be confused with the PICOSat series of microsatellites) is usually applied to the name of an artificial satellite with a wet mass between .1 and 1 kg. Again designs and proposed designs of these types usually have multiple picosatellites working together or in formation (sometimes the term "swarm" is applied). Some designs require a larger "mother" satellite for communication with ground controllers or for launching and docking with picosatellites. The [[CubeSat]] design, with 1 kg maximum mass, is an example of a large picosatellite (or minimum nanosat).

== Technical challenges ==

Micro/nanosats usually require innovative propulsion, [[attitude control]], communication and computation systems.

Larger satellites usually use [[monopropellant]]s or [[bipropellant]] [[combustion]] [[Rocket|rockets]] for propulsion and attitude control; these systems are complex and require a minimal amount of volume to surface area to dissipate heat. These systems are used on larger microsats, while other micro/nanosats have to use electric propulsion, compressed gas, vaporizable liquids such as [[butane]] or [[carbon dioxide]] or other innovative propulsion systems that are simple, cheap and scalable.

Microsats can use conventional radio systems in UHF, VHF, the S-band and X-band, although often miniaturized using more up-to-date technology as compared to larger satellites. Tiny satellites such as nanosats and small microsats may lack the power supply or mass for large conventional radio [[transponders]], and various miniaturized or innovative communications systems have been proposed, such a laser receivers, antenna arrays and satellite to satellite communication networks. Few of these have been demonstrated in practice.

Electronics need to be rigorously tested and modified to be "space hardened" or resistant to the outer space environment (vacuum, microgravity, thermal extremes, and radiation exposure). Miniaturized satellites allow for the opportunity to test new hardware with reduced expense in testing. Furthermore, since the overall cost risk in the mission is much lower, more up-to-date but less space-proven technology can be incorporated into micro and nanosats than can be used in much larger, more expensive missions with less appetite for risk.

Manufacturers of microsatellites include [[SpaceDev]] and [[Surrey Satellite Technology Ltd]].

Manufacturers of nanosatellites include GomSpace, ISIS and UTIAS-SFL.

[[SuitSat]], a retired spacesuit fitted with some basic instrumentation and radio transmitting equipment and released into orbit in 2006, was an unconventional example of a low-cost microsatellite test platform.

== See also ==
{|width=85%
||
* [[Wikipedia:Canadian Advanced Nanospace eXperiment Program]]
* [[Wikipedia:Micro air vehicle]]
* [[Wikipedia:N-prize]]
* [[Wikipedia:Nanosatellite Launch System]]
* [[Wikipedia:Satellite formation flying]]
||
* [[Wikipedia:Satellite constellation]]
* [[Wikipedia:SPHERES]]
* [[Wikipedia:Student Space Exploration & Technology Initiative]]
* [[Wikipedia:DRAGONSat]] picosatellite
* [[Wikipedia:University Nanosat Program]]
|}

== Citations ==
{{reflist|2}}

==External links==
*[http://www.edusat.info Edusat Project]
*http://marsnet.jpl.nasa.gov/index.html
*http://www.accessscience.com/ResUpdates/2004/YB_041170_frameset.html?doi
*[http://www.alteich.com/tidbits/t121399.htm Teich's Tech Tidbit of the Week December 13, 1999 Nanosats]

The reference WP missed, because they only used Google News, therefore deciding to scrap the article:
*[http://www.css.ca/index.php?option=com_content&view=article&id=333:new-sponsor-for-canadian-satellite-design-challenge&catid=47:earth-observation&Itemid=61 Geocentrix Welcomes Microsat Systems Canada Inc. (MSCI) as a Gold-Level CSDC Sponsor] Larry Reeves, Thursday, 05 August 2010 12:23, [[Wikipedia:Canadian Space Society]]

[[Category:Satellites]]

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 * Using formations to gather data from multiple points
 * In-orbit inspection of larger satellites.
-''This article contains content from Wikipedia. Parts of it [http://en.wikipedia.org/wiki/Wikipedia:Articles_for_deletion/COMMStellation were deleted from Wikipedia]''
 ==The Physics Behind Covering the Earth==
@@ Line 74: / Line 77: @@
 The reference WP missed, because they only used Google News, therefore deciding to scrap the article:
 *[http://www.css.ca/index.php?option=com_content&view=article&id=333:new-sponsor-for-canadian-satellite-design-challenge&catid=47:earth-observation&Itemid=61 Geocentrix Welcomes Microsat Systems Canada Inc. (MSCI) as a Gold-Level CSDC Sponsor] Larry Reeves, Thursday, 05 August 2010 12:23, [[Wikipedia:Canadian Space Society]]
+{{Wikipedia}}
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Microsatellite - Revision history

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