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Cosmic dust
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Porous chondrite interplanetary dust particle.
Cosmic dust can be taken to be all dust in the cosmos, as its name implies, or limited to space dust in the Solar System. It is for the most part a type of small dust particles which are a few molecules to 0.1 µm in size. A smaller fraction of all dust in space consists of larger refractory minerals that condensed as matter left the stars. It is called "stardust" and is included in a separate section below. The dust density in the local interstellar medium of the Local Bubble is approximately 10-6 × dust grain/m3 with each grain having a mass of approximately 10-17 kg.Cosmic dust can be further distinguished by its astronomical location: intergalactic dust, interstellar dust, interplanetary dust (such as in the zodiacal cloud) and circumplanetary dust (such as in a planetary ring). In the Solar System, interplanetary dust causes the zodiacal light. Sources of Solar System dust include comet dust, asteroidal dust, dust from the Kuiper belt, and interstellar dust passing through the Solar System. The terminology has no specific application for describing materials found on the planet Earth except for dust that has demonstrably fallen to Earth. By one estimate, as much as 40,000 tons of cosmic dust reaches the Earth's surface every year. In October 2011, scientists reported that cosmic dust contains complex organic matter ("amorphous organic solids with a mixed aromatic–aliphatic structure") that could be created naturally, and rapidly, by stars.On August 14, 2014, scientists announced the collection of possible interstellar dust particles from the Stardust spacecraft since returning to Earth in 2006.
^ "Applications of the Electrodynamic Tether to Interstellar Travel" Gregory L. Matloff, Less Johnson, February, 2005
^ "Spacecraft Measurements of the Cosmic Dust Flux", Herbert A. Zook. doi:10.1007/978-1-4419-8694-8_5
^ Chow, Denise (26 October 2011). "Discovery: Cosmic Dust Contains Organic Matter from Stars". Space.com. Retrieved 2011-10-26.
^ ScienceDaily Staff (26 October 2011). "Astronomers Discover Complex Organic Matter Exists Throughout the Universe". ScienceDaily. Retrieved 2011-10-27.
^ Kwok, Sun; Zhang, Yong (26 October 2011). "Mixed aromatic–aliphatic organic nanoparticles as carriers of unidentified infrared emission features". Nature 479 (7371): 80–3. Bibcode:2011Natur.479...80K. doi:10.1038/nature10542. |accessdate= requires |url= (help)
^ Agle, DC; Brown, Dwayne; Jeffs, William (August 14, 2014). "Stardust Discovers Potential Interstellar Space Particles". NASA. Retrieved August 14, 2014.
^ Dunn, Marcia (August 14, 2014). "Specks returned from space may be alien visitors". AP News. Retrieved August 14, 2014.
^ Hand, Eric (August 14, 2014). "Seven grains of interstellar dust reveal their secrets". Science (journal). Retrieved August 14, 2014.
^ Westphal, Andrew J. et al. (August 15, 2014). "Evidence for interstellar origin of seven dust particles collected by the Stardust spacecraft". Science (journal) 345 (6198): 786–791. doi:10.1126/science.1252496. Retrieved August 15, 2014.
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