hab nach längerem Suchen im Netz etwas gefunden:
http://www-space.arc.nasa.gov/~leonid/g ... rains.html
Grüße,
Mark
Infos über Nachleuchten von Meteoren (persistent trains)
-
Gunnar Glitscher
Re: Infos über Nachleuchten von Meteoren (persistent trains)
Hallo Mark,
hier noch was zum Thema: http://www.uark.edu/~meteor/abst36-9.htm
Gruß,
Gunnar
Meteoritics & Planetary Science 36 (2001)
© Meteoritical Society, 2001. Printed in USA.
Heterogeneous chemical processes as source of persistent meteor trains
Edmond Murad
Author's address: Space Vehicles Directorate, Air Force Research Laboratory, Hanscom AFB, Massachusetts 01731, USA; e-mail address: ed.murad@hanscom.af.mil
AbstractObservations of long-lasting persistent trains following the entry of some meteoroids into the Earth's atmosphere are suggested to arise in part from the interaction between meteoroid components and the atmosphere and in the heterogeneous recombination reaction of atmospheric O atoms with NO. The latter occurs on the surfaces of dust left by the explosive fragmentation of larger meteoroids. A strong role is attributed to reactions of troilite (FeS), a meteorite component, with the atmosphere at elevated temperatures. The suggestions made in this paper complement previous work that suggested that long-lived emissions results from a variety of species made in the shock of larger meteoroids.
> hab nach längerem Suchen im Netz etwas gefunden:
> http://www-space.arc.nasa.gov/~leonid/g ... rains.html
> Grüße,
> Mark
hier noch was zum Thema: http://www.uark.edu/~meteor/abst36-9.htm
Gruß,
Gunnar
Meteoritics & Planetary Science 36 (2001)
© Meteoritical Society, 2001. Printed in USA.
Heterogeneous chemical processes as source of persistent meteor trains
Edmond Murad
Author's address: Space Vehicles Directorate, Air Force Research Laboratory, Hanscom AFB, Massachusetts 01731, USA; e-mail address: ed.murad@hanscom.af.mil
AbstractObservations of long-lasting persistent trains following the entry of some meteoroids into the Earth's atmosphere are suggested to arise in part from the interaction between meteoroid components and the atmosphere and in the heterogeneous recombination reaction of atmospheric O atoms with NO. The latter occurs on the surfaces of dust left by the explosive fragmentation of larger meteoroids. A strong role is attributed to reactions of troilite (FeS), a meteorite component, with the atmosphere at elevated temperatures. The suggestions made in this paper complement previous work that suggested that long-lived emissions results from a variety of species made in the shock of larger meteoroids.
> hab nach längerem Suchen im Netz etwas gefunden:
> http://www-space.arc.nasa.gov/~leonid/g ... rains.html
> Grüße,
> Mark
-
Gunnar Glitscher
Weiterer Fund
http://www.meteorobs.org/maillist/msg07221.html
4. Where does a meteor's light and color come from? What is a meteor train?
The majority of light from a meteor radiates from a compact cloud of
gaseous atoms and molecules immediately surrounding the meteoroid or
closely trailing it. This cloud consists of a mixture of atoms and
molecules ablated from the meteoroid itself as well as from the surrounding
air. These excited particles will emit light at wavelengths characteristic
for each element/compound. The most common emission lines from meteors
originate from iron (Fe), oxygen (O), magnesium (Mg), sodium (Na), nitrogen
(N), and calcium (Ca). Less frequently seen are the emission lines of
hydrogen (H), Silicon (Si), Manganese (Mn), and Chromium (Cr).
While most meteors produce a wide blend of these emissions, giving the
meteor an overall white color, specifically colored meteors are often
reported by meteor observers. Usually, such colors are rather weak in
appearance; however, vivid colors are occasionally reported, especially
with fireballs. Reported colors range across the spectrum, from reds,
yellows, greens, and blues, to gold, orange, and (infrequently violet. The
velocity of the meteor also plays an important role, since a higher level
of kinetic energy will excite the atoms/molecules to a higher degree. Slow
meteors are often reported as red or orange, while fast meteors frequently
have a blue color. Due to the nearly identical composition and velocity of
meteors belonging to a particular shower, several showers are known for
their characteristically colored meteors.
Often, a brief glow will remain after the passage of the meteor. If this
glow persists for less than 0.5 seconds, it is called a wake. This residual
glow is caused by the same atoms which produced the original light from the
meteor, only at lower excitation energies.
If the glow from the meteor trail persists for a longer period, this is
called a meteor train. Trains are most often seen from fast, bright
meteors, in the altitude band from about 100 to 120 km (62 - 75 miles).
This type of train usually lasts about 1-2 seconds, and is primarily
generated by the green emissions of the neutral nitrogen atom. On very rare
occasions, a train may persist for several minutes, and will be observed to
change shape as the trail is blown by upper atmosphere winds. Such
persistent meteor trains provided scientists with their first data on winds
in this region.
end of excerpt.
The green color you reported matches with the neutral Nitrogen atom
emission mentioned above (although I don't know the exact wavelengths of
the most prominent line(s)).
Take care,
Jim
James Richardson
Graceville, Florida
richardson@digitalexp.com
Operations Manager / Radiometeor Project Coordinator
American Meteor Society (AMS)
http://www.serve.com/meteors/
4. Where does a meteor's light and color come from? What is a meteor train?
The majority of light from a meteor radiates from a compact cloud of
gaseous atoms and molecules immediately surrounding the meteoroid or
closely trailing it. This cloud consists of a mixture of atoms and
molecules ablated from the meteoroid itself as well as from the surrounding
air. These excited particles will emit light at wavelengths characteristic
for each element/compound. The most common emission lines from meteors
originate from iron (Fe), oxygen (O), magnesium (Mg), sodium (Na), nitrogen
(N), and calcium (Ca). Less frequently seen are the emission lines of
hydrogen (H), Silicon (Si), Manganese (Mn), and Chromium (Cr).
While most meteors produce a wide blend of these emissions, giving the
meteor an overall white color, specifically colored meteors are often
reported by meteor observers. Usually, such colors are rather weak in
appearance; however, vivid colors are occasionally reported, especially
with fireballs. Reported colors range across the spectrum, from reds,
yellows, greens, and blues, to gold, orange, and (infrequently violet. The
velocity of the meteor also plays an important role, since a higher level
of kinetic energy will excite the atoms/molecules to a higher degree. Slow
meteors are often reported as red or orange, while fast meteors frequently
have a blue color. Due to the nearly identical composition and velocity of
meteors belonging to a particular shower, several showers are known for
their characteristically colored meteors.
Often, a brief glow will remain after the passage of the meteor. If this
glow persists for less than 0.5 seconds, it is called a wake. This residual
glow is caused by the same atoms which produced the original light from the
meteor, only at lower excitation energies.
If the glow from the meteor trail persists for a longer period, this is
called a meteor train. Trains are most often seen from fast, bright
meteors, in the altitude band from about 100 to 120 km (62 - 75 miles).
This type of train usually lasts about 1-2 seconds, and is primarily
generated by the green emissions of the neutral nitrogen atom. On very rare
occasions, a train may persist for several minutes, and will be observed to
change shape as the trail is blown by upper atmosphere winds. Such
persistent meteor trains provided scientists with their first data on winds
in this region.
end of excerpt.
The green color you reported matches with the neutral Nitrogen atom
emission mentioned above (although I don't know the exact wavelengths of
the most prominent line(s)).
Take care,
Jim
James Richardson
Graceville, Florida
richardson@digitalexp.com
Operations Manager / Radiometeor Project Coordinator
American Meteor Society (AMS)
http://www.serve.com/meteors/
-
Claudia
Zeitrafferaufnahme
von der AKM-Leonidenexpedition 1999:
http://aipsoe.aip.de/~rend/leo98res.html
Gruß
Claudia aus Chemnitz
(wo nach 6 trüben Tagen endlich die Sonne wieder scheint...)
http://aipsoe.aip.de/~rend/leo98res.html
Gruß
Claudia aus Chemnitz
(wo nach 6 trüben Tagen endlich die Sonne wieder scheint...)
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