Abstract. Double station data on 496 meteors belonging to several meteor showers were obtained within the program of the video meteor observations during years 1998−2001. Analyzed meteors cover a range of photometric masses from 10to 10 −4 kg with a corresponding range of maximum brightness from +4.7 to −2.1 absolute magnitude. Atmospheric trajectories of Perseid, Orionid and Leonid meteors are analysed. These typical cometary high velocity meteors are compared to Geminid meteors with probable asteroidal origin and Taurid meteors -another cometary shower with significantly lower entry velocity. The light curves of the studied meteors vary widely, but generally are nearly symmetrical with the point of maximum brightness located close the to middle of the luminous trajectory. Small differences between showers are reported. We found that the height data are in good agreement with the dust-ball model predictions. The only difference is the beginning height behaviour. The beginning heights of cometary meteors increase with increasing photometric mass. These meteoroids probably contain a volatile part which starts to ablate before we are able to detect the meteors. The Geminid meteors are a different case. They start to ablate suddenly and their beginning height is almost constant in the whole range of studied meteoroid masses. In this case we observe real beginnings of meteor ablation.

Precise atmospheric trajectories including dynamic and photometric data on thirteen of the brightest Leonid fireballs have been determined from the double-station photographic observations of Leonid meteors during the ground-based expedition to China in 1998 November. The expedition was organized as a collaboration between the Dutch and Chinese Academy of Sciences and was supported by the Leonid multi-instrument aircraft campaign (MAC) program (Jenniskens and Butow, 1999). All data presented here were taken at Xinglong Observatory and at a remote station, Lin Ting Kou near Beijing, on the night of 1998 November 16/17. At the Xinglong station, photographic cameras were accompanied by an all-sky television camera equipped with an image intensifier and 15 mm fish-eye objective in order to obtain precise timings for all observed meteors up to magnitude +2. Whereas beginning heights of photographed meteors are all lower than 130 km, those observed by the all-sky television system are at -160 km, and for three brightest events, even > 180 km. Such high beginnings for meteors have never before been observed. We also obtained a precise dynamic single-body solution for the Leonid meteor 98003, including the ablation coefficient, which is an important material and structural quantity (0.16 s2 kn-2). From this and from known photometry, we derived a density of this meteoroid of 0.7 g/cm3. Also, all PE coefficients indicate that these Leonid meteors belonged to the fireball group IIIB, which is typical for the most fragile and weak interplanetary bodies. From a photometric study of the meteor lightcurves, we found two typical shapes of light curves for these Leonid meteors. (1997) Precisely reduced meteoroid trajectories and orbits from the 1995 Leonid meteor outburst. Planet. Space Sci. 45,853-856. CEPLECHA Z. (1987) Geometric, dynamic, orbital and photometric data on meteoroids from Dhotoeraohic fireball networks. Bull. Astron. Inst. -. Czech. 38,222-23i. Luminous efficiency based on photographic observations of the Lost City fireball and implications for the influx of interplanetary bodies onto Earth. Astron. Ashophys. 311,329-332.

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Abstract— Among the three large camera networks carrying out fireball observations through the seventies and eighties, the “European Fireball Network” is the last one still in operation. The network today consists of more than 34 all‐sky and fish‐eye cameras deployed with ∼100 km spacing and covering an area of ∼106 km2, in the Czech and Slovak Republics, Germany, as well as parts of Belgium, Switzerland, and Austria. Network operation results in ∼10 000 image exposures per year, which represent on average 1200 h of clear sky observations—as imaging periods are restricted due to daylight, moonlight, and clouds. The cameras detect currently large meteors at a rate of ∼50 per year; this is in good agreement with the encounter rates determined in previous fireball studies. From sightings of “meteorite candidates” (fireballs that may have deposited meteorites) and meteorite recoveries in the network area, we estimate that 15% of the influx of meteoritic matter is currently observed by the cameras, whereas <1% is recovered on the ground. Issues to be addressed by future fireball observations include the study of very large meteoroids (>1000 kg) for which statistics are currently very poor and an examination of their relationship to NEOs (near‐Earth objects) identified by current NEO search programs.

Abstract— In this paper, we study the extremely high beginning parts of atmospheric trajectories of seven Leonid meteors recorded by sensitive TV systems equipped with image intensifiers up to apparent magnitude +6.5. For all seven cases, we observed comet‐like diffuse structures with sizes on the order of kilometers that developed quickly during the meteoroids' descent through the atmosphere. For the brightest event with a maximum absolute magnitude of −12.5, we observed an arc similar to a solar protuberance and producing a jet detectable several kilometers sideways from the brightest parts of the meteor head, and moving with a velocity over 100 km/s. These jets are common features for the seven studied meteors. Precise position in trajectory, velocity, and brightness at each point is available for all seven meteors, because of double‐station records on 85 km base‐line. When these meteoroids reached 130 km height, their diffuse structures of the radiation quickly transformed to the usual meteor appearance resembling moving droplets, and meteor trains started to develop. These meteor phenomena above 130 km were not recognized before our observations, and they cannot be explained by standard ablation theory.