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Ian Wright - One of the best experts on this subject based on the ideXlab platform.
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The chemistry and origin of Micrometeoroid and space debris impacts on spacecraft surfaces
Dust in the Solar System and other Planetary Systems Proceedings of the IA U Colloquium 181 held at the University of Kent, 2002Co-Authors: Giles A. Graham, Anton T. Kearsley, Monica M. Grady, Ian Wright, G. Drolshagen, Hajime YanoAbstract:Laboratory investigations of impact residues captured on the solar cells from the Hubble Space Telescope and on insulation foils from the Space Flyer Unit demonstrate preservation of abundant and diverse Micrometeoroid and space debris remnants. Micrometeoroid residues often appear as complex melts of poly-mineralic origin derived from silicates, carbonates, metals and metal sulfides. The space debris includes paint-flakes, metal alloys and possible reactor coolant, but the most abundant components are aluminium and aluminium oxide remnants from solid rocket motor operation. The impactor origins have now been compared with the theoretical flux models for Low Earth Orbit.
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The chemistry of Micrometeoroid and space debris remnants captured on hubble space telescope solar cells
International Journal of Impact Engineering, 2001Co-Authors: G. A. Graham, J. A. M. Mcdonnell, Anton T. Kearsley, Gerhard Drolshagen, Neil Mcbride, Simon F. Green, Monica M. Grady, Ian WrightAbstract:Abstract Prior to the retrieval in 1993 from low Earth orbit (LEO), the “—V2” Solar Array wing of the Hubble Space Telescope was exposed to hypervelocity impacts (micrometre to millimetre scale) from both Micrometeoroids and space debris. The initial survey of the damage (100–3500μm diameter sized craters) identified that Micrometeoroid remnants dominated the flux in the 100–1000μm size regime, with debris dominating >1000μm. These residues were composed of remnants of silicate minerals, calcite, metal sulfides and metals that often appeared as complex poly-mineralic melts within melt pits. A further survey of 10–100μm diameter craters identified that the most common chemistry was space debris with the crossover from meteoroids to debris being at around 30μm DCO. Residues include remnants of specialised steels and paint fragments but the dominant type is aluminium and aluminium oxide, which are almost certainly remnants of solid rocket motor operations. It is found that the relative contribution of debris as a function of size, agrees remarkably with a prediction derived using flux data from Long Duration Exposure Facility and a meteoroid model.
Anton T. Kearsley - One of the best experts on this subject based on the ideXlab platform.
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The chemical composition of Micrometeoroids impacting upon the solar arrays of the Hubble Space Telescope
Advances in Space Research, 2007Co-Authors: Anton T. Kearsley, J. A. M. Mcdonnell, Giles A. Graham, Emma A. Taylor, Gerhard Drolshagen, Richard J. Chater, David S. Mcphail, Mark J. BurchellAbstract:Abstract Analytical scanning electron microscopy of solar cells returned from the Hubble Space Telescope (HST) at the end of HST Service Missions SM-1 (1993) and SM-3B (2002) has revealed abundant remains of Micrometeoroids. We have documented the most common residue compositions, and in this paper we suggest how they relate to mineral phases, and show how it is possible to estimate the proportion of the original Micrometeoroid preserved. From a total of 273 impacts examined and analysed, we found 61/162 impacts on solar cells from SM-1 were produced by Micrometeoroids, as were 45/111 from SM-3B. In each survey approximately 25% of damage features could not be assigned to a particular origin (Micrometeoroid or space debris). A cumulative Micrometeoroid flux curve for randomly selected cells shows impact features ranging from 3 to nearly 3800 μm in size. To assist interpretation of space exposed surfaces, impact residues from known meteoritic and terrestrial analogue mineral phases were produced by light gas gun assisted acceleration of buckshot projectiles into solar cell targets at 5.5–6.3 km s−1. Mg- and Fe-rich residues were found in 30/61 impacts from SM-1 and 26/45 from SM-3B, with variable Mg:Fe ratio, usually lacking Ca, and likely to be from olivine or low-Ca pyroxene. Only in a few examples is it possible to determine the divalent cation to silicon ratio, and thereby positively identify olivine or pyroxene. Vesicular Fe-, Mg-, Ni- and S-rich residues, found in eight impacts from SM-1 and 5 from SM-3B, closely resemble residue from light gas gun shots of phyllosilicate-rich meteorite grains, and may be from a layered silicate such as serpentine or smectite interlayered with tochilinite. Fe- and S-rich immiscible melt droplets, low in nickel, are probably of troilite origin. Fe-, Ni- and P-rich residue is almost certainly from the phosphide schreibersite, and iron–nickel metal residues show an elemental ratio characteristic of kamacite. One Mg-, Cr-, Fe- and O-rich residue suggests a spinel precursor. Ca-rich particles found within the spall zone of several craters closely resemble residue from calcium carbonate. Mg sulfates are also present. Very little aluminous silicate residue was found (one residue from each survey). One extraordinarily well-preserved assemblage contains residues from five mineral components and may represent impact by a chondrule fragment. Derivation of incident particle sizes from impact feature dimensions, by use of calibrated damage equations, reveals that the majority of impacting Micrometeoroids had diameters of less than 10 μm, although the mass flux is concentrated in grains of more than 50 μm diameter. In one well-preserved crater, the mass of residue was calculated to be 60 ng, approximately 25% of the particle mass as suggested by experimental crater size calibration. The smallest impacts were produced by grains of between 600 nm and 1.3 μm. The most common residue assemblages suggest that the majority of micron to millimetre scale Micrometeoroids have an origin from chondritic material, similar to interplanetary dust particles, micrometeorites, and possibly the hydrous carbonaceous chondrites of the CM, CR or CI group. The relative contribution of cometary as opposed to asteroidal particle sources cannot yet be assessed from this data set.
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Multi-layered foil capture of Micrometeoroids and orbital debris in low Earth orbit
Advances in Space Research, 2004Co-Authors: Anton T. Kearsley, Giles A. GrahamAbstract:Abstract Analyses of multi-layered polymer insulation foils recovered from the Japanese Space Flyer Unit suggest that such foils have the potential to retain substantial remnants of Micrometeoroid and space debris material from hypervelocity impact events. A purpose-built multi-layer foil collector could sample large numbers of impacts from smaller particles in low Earth orbit. Abundant residue could be classified as spece debris or Micrometeoroid in origin, both quickly and easily – a significant improvement over materials surveyed on an opportunistic basis (such as solar cells, aluminium surfaces and aluminised multi-layer insulation foils) or metallic foil collectors, in that it would allow recognition of the whole range of impacted projectile compositions in a single survey. The collector is also intended to be relatively easy and cheap to construct, light in weight, negligible in power requirements, easy to deploy, of large surface area, easy to retrieve, small in storage, and unlikely to acquire substantial contamination upon the crucial inner foils.
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The chemistry and origin of Micrometeoroid and space debris impacts on spacecraft surfaces
Dust in the Solar System and other Planetary Systems Proceedings of the IA U Colloquium 181 held at the University of Kent, 2002Co-Authors: Giles A. Graham, Anton T. Kearsley, Monica M. Grady, Ian Wright, G. Drolshagen, Hajime YanoAbstract:Laboratory investigations of impact residues captured on the solar cells from the Hubble Space Telescope and on insulation foils from the Space Flyer Unit demonstrate preservation of abundant and diverse Micrometeoroid and space debris remnants. Micrometeoroid residues often appear as complex melts of poly-mineralic origin derived from silicates, carbonates, metals and metal sulfides. The space debris includes paint-flakes, metal alloys and possible reactor coolant, but the most abundant components are aluminium and aluminium oxide remnants from solid rocket motor operation. The impactor origins have now been compared with the theoretical flux models for Low Earth Orbit.
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The chemistry of Micrometeoroid and space debris remnants captured on hubble space telescope solar cells
International Journal of Impact Engineering, 2001Co-Authors: G. A. Graham, J. A. M. Mcdonnell, Anton T. Kearsley, Gerhard Drolshagen, Neil Mcbride, Simon F. Green, Monica M. Grady, Ian WrightAbstract:Abstract Prior to the retrieval in 1993 from low Earth orbit (LEO), the “—V2” Solar Array wing of the Hubble Space Telescope was exposed to hypervelocity impacts (micrometre to millimetre scale) from both Micrometeoroids and space debris. The initial survey of the damage (100–3500μm diameter sized craters) identified that Micrometeoroid remnants dominated the flux in the 100–1000μm size regime, with debris dominating >1000μm. These residues were composed of remnants of silicate minerals, calcite, metal sulfides and metals that often appeared as complex poly-mineralic melts within melt pits. A further survey of 10–100μm diameter craters identified that the most common chemistry was space debris with the crossover from meteoroids to debris being at around 30μm DCO. Residues include remnants of specialised steels and paint fragments but the dominant type is aluminium and aluminium oxide, which are almost certainly remnants of solid rocket motor operations. It is found that the relative contribution of debris as a function of size, agrees remarkably with a prediction derived using flux data from Long Duration Exposure Facility and a meteoroid model.
D. Maravilla - One of the best experts on this subject based on the ideXlab platform.
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The electrical effects of Micrometeoroids entering the terrestrial atmosphere at different speeds
Journal of Plasma Physics, 2010Co-Authors: D. A. Mendis, D. MaravillaAbstract:AbstractMicrometeoroids entering the terrestrial atmosphere lead to two important related electrical effects. One is the electrification of the upper atmosphere along their paths and the other is the electrical charging of the Micrometeoroids themselves. In this brief note we will emphasize the central role of the initial encounter speed of the incoming Micrometeoroid, showing how it changes the altitude profiles of electron production and electrical charging, not just quantitatively but also qualitatively. We will discuss the underlying reasons for this, as well as their importance in meteor studies.
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A note on the altitude profiles of the electron production in the atmosphere by Micrometeoroids entering it at different initial speeds
Geophysical Research Letters, 2009Co-Authors: D. A. Mendis, D. MaravillaAbstract:[1] We have extended our earlier model (Mendis et al., 2005) for the study of the dynamical, thermal and charging history of Micrometeoroids entering the earth's atmosphere, by taking into account the role of sputtering, which is important for high-speed ones. As before we confine ourselves to motion in the night side of the earth. In this short note we will not discuss these, but will confine our attention to the limited, yet important, effect of electron production in the atmosphere, by three different classes of Micrometeoroids (fast—“cometary,” average—“cometary,” and slow—“asteroidal”). It is seen that the altitude profiles of the electron production, which lead to the radar signatures of these bodies, are different, not just quantitatively but also qualitatively. This is due to the different relative importance of the three processes responsible for electron production, namely the ones associated with ablation and sputtering of the infalling Micrometeoroid and thermionic electron emission from it. It is seen that sputtering-associated electron production is the dominant process, particularly at higher altitudes, for the fast Micrometeoroid (initial entry speed 60 km/s), ablation-associated electron production is the dominant process for the average one (initial entry speed 30 km/s), while thermionic electron emission is the dominant process for the slow one (initial entry speed 12.5 km/s).
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Dynamics of charged Micrometeoroids entering the Earth's atmosphere
2009Co-Authors: D. Maravilla, D. A. Mendis, Investigaciones SolaresAbstract:In this work we present a consistent theoretical model in order to study the electrical charging, deceleration, heating, ablation, and sputtering of a low work function Micrometeoroid entering the Earths atmosphere. In the model we have calculated the production rate of electrons along the meteoroids path considering both the ionization generated by collisions and the background molecules in the atmosphere. We have simultaneously solved the equations of continuity of charge, mass, momentum and energy in order to study the Micrometeoroids dynamics and the results show these tiny bodies can have different charge polarities with small negative potential during their paths for all analyzed cases. Particularly for 100 and 40 micron-sized bodies, we have found some differences between thermionic emission of electrons and electron production associated with ablation. With regard to sputtering rate there are also some differences although they are small when we compare the sputtering rate for these both sizes.
G. A. Graham - One of the best experts on this subject based on the ideXlab platform.
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The chemistry of Micrometeoroid and space debris remnants captured on hubble space telescope solar cells
International Journal of Impact Engineering, 2001Co-Authors: G. A. Graham, J. A. M. Mcdonnell, Anton T. Kearsley, Gerhard Drolshagen, Neil Mcbride, Simon F. Green, Monica M. Grady, Ian WrightAbstract:Abstract Prior to the retrieval in 1993 from low Earth orbit (LEO), the “—V2” Solar Array wing of the Hubble Space Telescope was exposed to hypervelocity impacts (micrometre to millimetre scale) from both Micrometeoroids and space debris. The initial survey of the damage (100–3500μm diameter sized craters) identified that Micrometeoroid remnants dominated the flux in the 100–1000μm size regime, with debris dominating >1000μm. These residues were composed of remnants of silicate minerals, calcite, metal sulfides and metals that often appeared as complex poly-mineralic melts within melt pits. A further survey of 10–100μm diameter craters identified that the most common chemistry was space debris with the crossover from meteoroids to debris being at around 30μm DCO. Residues include remnants of specialised steels and paint fragments but the dominant type is aluminium and aluminium oxide, which are almost certainly remnants of solid rocket motor operations. It is found that the relative contribution of debris as a function of size, agrees remarkably with a prediction derived using flux data from Long Duration Exposure Facility and a meteoroid model.
Gerhard Drolshagen - One of the best experts on this subject based on the ideXlab platform.
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The chemical composition of Micrometeoroids impacting upon the solar arrays of the Hubble Space Telescope
Advances in Space Research, 2007Co-Authors: Anton T. Kearsley, J. A. M. Mcdonnell, Giles A. Graham, Emma A. Taylor, Gerhard Drolshagen, Richard J. Chater, David S. Mcphail, Mark J. BurchellAbstract:Abstract Analytical scanning electron microscopy of solar cells returned from the Hubble Space Telescope (HST) at the end of HST Service Missions SM-1 (1993) and SM-3B (2002) has revealed abundant remains of Micrometeoroids. We have documented the most common residue compositions, and in this paper we suggest how they relate to mineral phases, and show how it is possible to estimate the proportion of the original Micrometeoroid preserved. From a total of 273 impacts examined and analysed, we found 61/162 impacts on solar cells from SM-1 were produced by Micrometeoroids, as were 45/111 from SM-3B. In each survey approximately 25% of damage features could not be assigned to a particular origin (Micrometeoroid or space debris). A cumulative Micrometeoroid flux curve for randomly selected cells shows impact features ranging from 3 to nearly 3800 μm in size. To assist interpretation of space exposed surfaces, impact residues from known meteoritic and terrestrial analogue mineral phases were produced by light gas gun assisted acceleration of buckshot projectiles into solar cell targets at 5.5–6.3 km s−1. Mg- and Fe-rich residues were found in 30/61 impacts from SM-1 and 26/45 from SM-3B, with variable Mg:Fe ratio, usually lacking Ca, and likely to be from olivine or low-Ca pyroxene. Only in a few examples is it possible to determine the divalent cation to silicon ratio, and thereby positively identify olivine or pyroxene. Vesicular Fe-, Mg-, Ni- and S-rich residues, found in eight impacts from SM-1 and 5 from SM-3B, closely resemble residue from light gas gun shots of phyllosilicate-rich meteorite grains, and may be from a layered silicate such as serpentine or smectite interlayered with tochilinite. Fe- and S-rich immiscible melt droplets, low in nickel, are probably of troilite origin. Fe-, Ni- and P-rich residue is almost certainly from the phosphide schreibersite, and iron–nickel metal residues show an elemental ratio characteristic of kamacite. One Mg-, Cr-, Fe- and O-rich residue suggests a spinel precursor. Ca-rich particles found within the spall zone of several craters closely resemble residue from calcium carbonate. Mg sulfates are also present. Very little aluminous silicate residue was found (one residue from each survey). One extraordinarily well-preserved assemblage contains residues from five mineral components and may represent impact by a chondrule fragment. Derivation of incident particle sizes from impact feature dimensions, by use of calibrated damage equations, reveals that the majority of impacting Micrometeoroids had diameters of less than 10 μm, although the mass flux is concentrated in grains of more than 50 μm diameter. In one well-preserved crater, the mass of residue was calculated to be 60 ng, approximately 25% of the particle mass as suggested by experimental crater size calibration. The smallest impacts were produced by grains of between 600 nm and 1.3 μm. The most common residue assemblages suggest that the majority of micron to millimetre scale Micrometeoroids have an origin from chondritic material, similar to interplanetary dust particles, micrometeorites, and possibly the hydrous carbonaceous chondrites of the CM, CR or CI group. The relative contribution of cometary as opposed to asteroidal particle sources cannot yet be assessed from this data set.
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Experimental verification of a Micrometeoroid damage in the pn-CCD camera system aboard XMM-Newton
X-Ray and Gamma-Ray Telescopes and Instruments for Astronomy, 2003Co-Authors: Norbert Meidinger, Gerhard Drolshagen, Bernd Aschenbach, Heinrich W. Braeuninger, Jakob Englhauser, Robert Hartmann, Gisela Hartner, Ralf Srama, Lothar Strueder, Martin A. StuebigAbstract:The pn-CCD is the focal plane detector of one of the three X-ray telescopes aboard the XMM-Newton observatory. During revolution #156 more than 30 individual bright pixels lightened up out of approximately 150,000 pixels of the 6 cm × 6 cm large detector area. The amount of leakage current generated in the pixels cannot be explained by single heavy ions impact, however. We suggest that a Micrometeoroid scattered off the mirror surface under grazing incidence reached the focal plane detector and produced the bright pixels. This proposal was studied by us experimentally at the Heidelberg dust accelerator. Micron-sized iron particles were accelerated to speeds of the order of 5 km/s impinging on the surface of an X-ray mirror under grazing incidence. Scatter products have been found with detectors placed behind the mirror. They have been analyzed by various methods to characterize their properties and the effects produced by them in the pn-CCD. Micrometeoroid damage to semiconductor detectors in the focus of grazing incidence optics might be of concern for future space projects with very large collecting area and are proposed to be studied in detail.
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The chemistry of Micrometeoroid and space debris remnants captured on hubble space telescope solar cells
International Journal of Impact Engineering, 2001Co-Authors: G. A. Graham, J. A. M. Mcdonnell, Anton T. Kearsley, Gerhard Drolshagen, Neil Mcbride, Simon F. Green, Monica M. Grady, Ian WrightAbstract:Abstract Prior to the retrieval in 1993 from low Earth orbit (LEO), the “—V2” Solar Array wing of the Hubble Space Telescope was exposed to hypervelocity impacts (micrometre to millimetre scale) from both Micrometeoroids and space debris. The initial survey of the damage (100–3500μm diameter sized craters) identified that Micrometeoroid remnants dominated the flux in the 100–1000μm size regime, with debris dominating >1000μm. These residues were composed of remnants of silicate minerals, calcite, metal sulfides and metals that often appeared as complex poly-mineralic melts within melt pits. A further survey of 10–100μm diameter craters identified that the most common chemistry was space debris with the crossover from meteoroids to debris being at around 30μm DCO. Residues include remnants of specialised steels and paint fragments but the dominant type is aluminium and aluminium oxide, which are almost certainly remnants of solid rocket motor operations. It is found that the relative contribution of debris as a function of size, agrees remarkably with a prediction derived using flux data from Long Duration Exposure Facility and a meteoroid model.