Information about Interplanetary Dust Cloud
The interplanetary dust cloud has been studied for many years in order
to understand its nature, origin, and relationship to planetary systems
(our own, as well as extrasolar systems).
The interplanetary dust particles (IDPs) not only scatter solar light (called the "zodiacal light", which is confined to the ecliptic plane), the IDPs also produce thermal emission, which is the most prominent feature of the night-sky light in the 5-50 micrometer wavelength domain (Levasseur-Regourd, A.C. 1996). The grains characterizing the infrared emission near the earth's orbit have typical sizes of 10-100 micrometers (Backman, D., 1997). The total mass of the interplanetary dust cloud is about the mass of an asteroid of radius 15 km (with density of about 2.5 g/cm3).
The sources of IDPs include at least: asteroid collisions, cometary activity and collisions in the inner solar system, Kuiper Belt collisions, and interstellar medium (ISM) grains (Backman, D., 1997). Indeed, one of the longest-standing controversies debated in the interplanetary dust community revolves around the relative contributions to the interplanetary dust cloud from asteroid collisions and cometary activity.
The main physical processes "affecting" (destruction or expulsion mechanisms) IDPs are: expulsion by radiation pressure, inward Poynting-Robertson (PR) radiation drag, solar wind pressure (with significant electromagnetic effects), sublimation, mutual collisions, and the dynamical effects of planets (Backman, D., 1997).
The lifetimes of these dust particles are very short compared to the lifetime of the Solar System. If one finds grains around a star that is older than about 10^8 years, then the grains must have been from recently released fragments of larger objects, i.e. they cannot be leftover grains from the protoplanetary disk (Backman, private communication). Therefore, the grains would be "later-generation" dust. The zodiacal dust in the solar system is 99.9% later-generation dust and 0.1% intruding ISM dust. All primordial grains from the Solar System's formation were removed long ago.
The interplanetary dust cloud has a complex structure (Reach, W., 1997). Apart from a background density, this includes:
Jackson A.A.; Zook, H.A. (1992). "Orbital evolution of dust particles from comets and asteroids". Icarus 97: 70-84.
Backman, Dana (1997). "Exozody Workshop, NASA-Ames, October 23-25, 1997". Extrasolar Zodiacal Emission - NASA Study Panel Report.
See: [1]
Dermott, S.F. Jayaraman, S., Xu, Y.L., Gustafson, A.A.S., Liou, J.C., (June 30, 1994). "RA circumsolar ring of asteroid dust in resonant lock with the Earth". Nature 360: 79-?.
Dermott, S.F. (1997). "Signatures of Planets in Zodiacal Light". Extrasolar Zodiacal Emission - NASA Study Panel Report.
Levasseur-Regourd, A.C. (1996). "Optical and Thermal Properties of Zodiacal Dust". ''Physics, Chemistry and Dynamics of Interplanetary Dust, ASP Conference series, Vol 104'': 301-.
Reach, W. (1997). "General Structure of the Zodiacal Dust Cloud". Extrasolar Zodiacal Emission - NASA Study Panel Report.
Reach, W.T.; Franz, B.A.; Weiland, J.L. (1997). "The Three-Dimensional Structure of the Zodiacal Dust Bands". Icarus 127: 461.
A thermal column (or thermal) is a column of rising air in the lower altitudes of the Earth's atmosphere.
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The interplanetary dust particles (IDPs) not only scatter solar light (called the "zodiacal light", which is confined to the ecliptic plane), the IDPs also produce thermal emission, which is the most prominent feature of the night-sky light in the 5-50 micrometer wavelength domain (Levasseur-Regourd, A.C. 1996). The grains characterizing the infrared emission near the earth's orbit have typical sizes of 10-100 micrometers (Backman, D., 1997). The total mass of the interplanetary dust cloud is about the mass of an asteroid of radius 15 km (with density of about 2.5 g/cm3).
The sources of IDPs include at least: asteroid collisions, cometary activity and collisions in the inner solar system, Kuiper Belt collisions, and interstellar medium (ISM) grains (Backman, D., 1997). Indeed, one of the longest-standing controversies debated in the interplanetary dust community revolves around the relative contributions to the interplanetary dust cloud from asteroid collisions and cometary activity.
The main physical processes "affecting" (destruction or expulsion mechanisms) IDPs are: expulsion by radiation pressure, inward Poynting-Robertson (PR) radiation drag, solar wind pressure (with significant electromagnetic effects), sublimation, mutual collisions, and the dynamical effects of planets (Backman, D., 1997).
The lifetimes of these dust particles are very short compared to the lifetime of the Solar System. If one finds grains around a star that is older than about 10^8 years, then the grains must have been from recently released fragments of larger objects, i.e. they cannot be leftover grains from the protoplanetary disk (Backman, private communication). Therefore, the grains would be "later-generation" dust. The zodiacal dust in the solar system is 99.9% later-generation dust and 0.1% intruding ISM dust. All primordial grains from the Solar System's formation were removed long ago.
The interplanetary dust cloud has a complex structure (Reach, W., 1997). Apart from a background density, this includes:
- At least 8 dust trails -- their source is thought to be short-period comets.
- A number of dust bands, the sources of which are thought to be asteroid families in the main asteroid belt. The three strongest bands arise from the Themis family, the Koronis family, and the Eos family. Other source families include the Maria, Eunomia, and possibly the Vesta and/or Hygiea families (Reach et al 1996).
- at least 2 resonant dust rings are known (for example, the Earth-resonant dust ring, although every planet in the solar system is thought to have a resonant ring with a "wake") (Jackson and Zook, 1988, 1992) ,(Dermott, S.F. et al., 1994, 1997)
References
Jackson A.A.; Zook, H.A. (1988). "A Solar System Dust Ring with the Earth as its Shepherd". Nature 337: 629.Jackson A.A.; Zook, H.A. (1992). "Orbital evolution of dust particles from comets and asteroids". Icarus 97: 70-84.
Backman, Dana (1997). "Exozody Workshop, NASA-Ames, October 23-25, 1997". Extrasolar Zodiacal Emission - NASA Study Panel Report.
See: [1]
Dermott, S.F. Jayaraman, S., Xu, Y.L., Gustafson, A.A.S., Liou, J.C., (June 30, 1994). "RA circumsolar ring of asteroid dust in resonant lock with the Earth". Nature 360: 79-?.
Dermott, S.F. (1997). "Signatures of Planets in Zodiacal Light". Extrasolar Zodiacal Emission - NASA Study Panel Report.
Levasseur-Regourd, A.C. (1996). "Optical and Thermal Properties of Zodiacal Dust". ''Physics, Chemistry and Dynamics of Interplanetary Dust, ASP Conference series, Vol 104'': 301-.
Reach, W. (1997). "General Structure of the Zodiacal Dust Cloud". Extrasolar Zodiacal Emission - NASA Study Panel Report.
Reach, W.T.; Franz, B.A.; Weiland, J.L. (1997). "The Three-Dimensional Structure of the Zodiacal Dust Bands". Icarus 127: 461.
planetary system consists of the various non-stellar objects orbiting a star such as planets, moons, asteroids, meteoroids, comets, and cosmic dust.[1][2] The Sun together with its planetary system, which includes Earth, is known as the Solar System.
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Cosmic dust is a type of dust composed of particles in space which are a few molecules to 0.1 mm in size. Cosmic dust can be further distinguished by its astronomical location; for example: intergalactic dust, interstellar dust, circumplanetary dust, dust clouds around other stars,
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The zodiacal light is a faint, roughly triangular, whitish glow seen in the night sky which appears to extend up from the vicinity of the sun along the ecliptic or zodiac.
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ecliptic is the apparent path that the Sun traces out in the sky, as it appears to move in the sky in relation to the stars, this apparent path aligns with the planets throughout the course of the year.
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- thermal, see thermal (disambiguation).
A thermal column (or thermal) is a column of rising air in the lower altitudes of the Earth's atmosphere.
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In physics, emission is the process by which the energy of a photon is released by another entity, for example, by an atom whose electrons make a transition between two electronic energy levels. The photon is created in the process.
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19th century - 20th century - 21st century
1960s 1970s 1980s - 1990s - 2000s 2010s 2020s
1993 1994 1995 - 1996 - 1997 1998 1999
Year 1996 (MCMXCVI
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1960s 1970s 1980s - 1990s - 2000s 2010s 2020s
1993 1994 1995 - 1996 - 1997 1998 1999
Year 1996 (MCMXCVI
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EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001. Their greatest hit, their debut single "time after time", peaked at #13 in the Oricon singles chart.
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ORBit is a CORBA compliant Object Request Broker (ORB). The current version is called ORBit2 and is compliant with CORBA version 2.4. It is developed under the GPL license and is used as middleware for the GNOME project.
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1 metre =
SI units
1000 mm 0 cm
US customary / Imperial units
0 ft 0 in
The metre or meter[1](symbol: m) is the fundamental unit of length in the International System of Units (SI).SI units
1000 mm 0 cm
US customary / Imperial units
0 ft 0 in
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20th century - 21st century
1960s 1970s 1980s - 1990s - 2000s 2010s 2020s
1994 1995 1996 - 1997 - 1998 1999 2000
Year 1997 (MCMXCVII
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1960s 1970s 1980s - 1990s - 2000s 2010s 2020s
1994 1995 1996 - 1997 - 1998 1999 2000
Year 1997 (MCMXCVII
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Asteroids, also called minor planets or planetoids, are a class of astronomical objects. The term asteroid is generally used to indicate a diverse group of small celestial bodies in the solar system that orbit around the Sun.
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comet is a small body in the solar system that orbits the Sun and (at least occasionally) exhibits a coma (or atmosphere) and/or a tail — both primarily from the effects of solar radiation upon the comet's nucleus, which itself is a minor body composed of rock, dust, and
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Kuiper belt (pronounced IPA: /ˈkaɪpɚ/, to rhyme with "viper"),[1] sometimes called the Edgeworth-Kuiper belt
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Radiation pressure is the pressure exerted upon any surface exposed to electromagnetic radiation. If absorbed, the pressure is the energy flux density divided by the speed of light. If the radiation is totally reflected, the radiation pressure is doubled.
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The Poynting-Robertson effect, also known as Poynting-Robertson drag, named after John Henry Poynting and Howard Percy Robertson, is a process by which solar radiation causes a dust grain in the solar system to slowly spiral inward.
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solar wind is a stream of charged particles (i.e., a plasma) which are ejected from the upper atmosphere of the sun. It consists mostly of high-energy electrons and protons (about 1 keV) that are able to escape the sun's gravity in part because of the high temperature of the corona
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Sublimation can have several meanings:
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- Sublimation (chemistry), the change from solid to gas, while at no point becoming a liquid.
- Sublimation (psychology), the transformation of emotions.
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Solar System or solar system[a] consists of the Sun and the other celestial objects gravitationally bound to it: the eight planets, their 166 known moons,[1]
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protoplanetary disk (or proplyd) is a rotating disk of dense gas surrounding a young newly formed star, a T Tauri star or Herbig star. The protoplanetary disk may be considered an accretion disk because gaseous material may be falling from the inner edge of the disk onto the
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An asteroid family is a group of minor planets that share similar orbital elements, such as semimajor axis, eccentricity, and orbital inclination. The members of the families are thought to be fragments of past asteroid collisions.
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asteroid belt is the region of the Solar System located roughly between the orbits of the planets Mars and Jupiter where 98.5% of the known minor planets' orbits can be found.
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The Themis Asteroid Family is a Hirayama family of asteroids found in the outer portion of the main asteroid belt, between the orbits of Mars and Jupiter. At a mean distance of 3.13 AU (Astronomical Units) from the Sun, it is one of the more populous .
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The Koronis family is a family of asteroids in the Main Belt between Mars and Jupiter. They are thought to have have been formed at least two billion years ago in a catastrophic collision between two larger bodies.
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The Eos family is a prominent family of asteroids that is believed to have formed as a result of an ancient catastrophic collision. Members of the family share similar orbits. The family is named after 221 Eos.
The Eos family asteroids have semimajor axes between 2.99 and 3.
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The Eos family asteroids have semimajor axes between 2.99 and 3.
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The Maria asteroids are a group of asteroids that orbit the sun with a between about 2.5 and 2.706 AU. Asteroids in this family typically have an inclination of 12 to 17 degrees.[1] The family gets its name from the asteroid 170 Maria.
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The Vesta family of asteroids is a large and prominent grouping of mostly V-type asteroids in inner main belt in the vicinity of 4 Vesta. Approximately 6% of main belt asteroids belong to this family.
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The Hygiea family of asteroids is a grouping of dark, carbonaceous C-type and B-type asteroids in outer main belt, the largest member of which is 10 Hygiea. About 1% of all known main belt asteroids belong to this family.
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