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: http://star.arm.ac.uk/press/2014/209P.html
Дата изменения: Thu May 22 17:43:31 2014 Дата индексирования: Sun Apr 10 05:25:06 2016 Кодировка: Поисковые слова: comet tail |
Meteor outburst predicted for 2014 May 24th, peak activity close to 07:00 UT. Significant proportion of bright meteors; possibility of fireballs.
Table of 209P trail encounters in 2014 May
Comments on the data in the table
Could the outburst fail to occur?
Which parts of the world can see the meteors?
Time adjustment (topocentric correction)
Further Web links
In this context "dust trail theory" refers to the fact that the set of meteoroids released from a parent comet during a single perihelion return stretch out into a dense, narrow dust trail during their early orbital evolution. The theory calculates (by numerical integration) the evolution of a single, representative particle at each point along the trail, rather than calculating the evolution of particles with any possible 3-dimensional ejection velocity. A meteor outburst is predicted if a trail comes close enough to the earth. This technique works if the timescale is short enough. The idea goes back many years (e.g. Plavec 1956) and was successfully applied by the Kazan research group (Kondrat'eva & Reznikov 1985, Kondrat'eva et al. 1997 etc.) to many streams.
For comet 209P, dust trail encounters were first calculated by Esko Lyytinen when Peter Jenniskens realised the possibility of close approaches (Jenniskens 2006). Further extensive dust trail calculations were made by Mikhail Maslov (2014 outburst; description; computation and comet orbit; 1901-2100 predictions). The data in the table below were calculated by David Asher with the same program used for the Leonids by McNaught & Asher (1999).
UT - Universal Time unadjusted for topocentric correction
Revs - number of orbits of dust from ejection to 2014
Ep - ejection epoch (year)
Da0 - difference between semi-major axis (a0) of
the comet and the particle at ejection. Da0~0.0 => large particles
rE-rD - distance of the dust trail node from Earth's orbit
(Earth radius=0.00004AU) (Impact radius=0.00005AU) (trail widths can easily
be a few Earth diameters, depending on ejection velocities)
fM - estimate of the along-trail dispersion. For a 1-rev trail,
fM= 1.0 but for an unperturbed n-rev trail, fM= 1/n.
Negative values indicate that the trail has bent backwards on itself.
Year Mo Da | UT | Revs | Ep | Da0 | rE-rD | fM |
---|---|---|---|---|---|---|
2014 05 24 | 08:00 | 20 | 1914 | 0.002 | 0.00202 | -0.229 |
2014 05 24 | 07:24 | 21 | 1909 | 0.001 | 0.00061 | -0.149 |
2014 05 24 | 07:09 | 22 | 1903 | 0.001 | 0.00005 | -0.113 |
2014 05 24 | 07:01 | 23 | 1898 | 0.001 | -0.00025 | -0.095 |
2014 05 24 | 06:55 | 24 | 1893 | 0.001 | -0.00044 | -0.082 |
2014 05 24 | 06:52 | 25 | 1888 | 0.000 | -0.00057 | -0.074 |
2014 05 24 | 06:48 | 26 | 1883 | 0.000 | -0.00067 | -0.067 |
2014 05 24 | 06:45 | 27 | 1878 | 0.000 | -0.00079 | -0.050 |
2014 05 24 | 06:42 | 28 | 1873 | 0.000 | -0.00086 | -0.040 |
2014 05 24 | 06:39 | 29 | 1868 | 0.000 | -0.00090 | -0.033 |
Year Mo Da | UT | Revs | Ep | Da0 | rE-rD | fM |
2014 05 24 | 06:38 | 30 | 1863 | 0.000 | -0.00093 | -0.029 |
2014 05 24 | 06:37 | 31 | 1858 | 0.000 | -0.00095 | -0.026 |
2014 05 24 | 06:37 | 32 | 1853 | 0.000 | -0.00096 | -0.020 |
2014 05 24 | 06:35 | 33 | 1848 | 0.000 | -0.00097 | -0.021 |
2014 05 24 | 06:34 | 34 | 1843 | 0.000 | -0.00097 | -0.022 |
2014 05 24 | 06:34 | 35 | 1838 | 0.000 | -0.00099 | -.--- |
2014 05 24 | 06:34 | 36 | 1833 | 0.000 | -0.00100 | -.--- |
2014 05 24 | 06:34 | 37 | 1828 | 0.000 | -0.00101 | -.--- |
2014 05 24 | 06:34 | 38 | 1823 | 0.000 | -0.00102 | -.--- |
2014 05 24 | 06:34 | 39 | 1818 | 0.000 | -0.00102 | -.--- |
Year Mo Da | UT | Revs | Ep | Da0 | rE-rD | fM |
2014 05 24 | 06:34 | 40 | 1813 | 0.000 | -0.00101 | -.--- |
2014 05 24 | 06:34 | 41 | 1808 | 0.000 | -0.00101 | -.--- |
2014 05 24 | 06:38 | 42 | 1803 | 0.000 | -0.00099 | -0.017 |
2014 05 24 | 06:37 | 43 | 1798 | 0.000 | -0.00096 | -0.023 |
2014 05 24 | 06:39 | 44 | 1793 | 0.000 | -0.00091 | -0.031 |
2014 05 24 | 06:47 | 45 | 1788 | 0.000 | -0.00078 | -0.054 |
2014 05 24 | 07:14 | 46 | 1783 | 0.001 | -0.00043 | -0.116 |
2014 05 24 | 07:47 | 47 | 1778 | 0.001 | 0.00001 | -0.047 |
2014 05 24 | 08:02 | 48 | 1773 | 0.001 | 0.00019 | -.--- |
2014 05 24 | 08:09 | 49 | 1768 | 0.001 | 0.00030 | -.--- |
2014 05 24 | 08:14 | 50 | 1763 | 0.001 | 0.00038 | -.--- |
2014 05 24 | 08:19 | 51 | 1758 | 0.001 | 0.00046 | -.--- |
2014 05 24 | 08:22 | 52 | 1753 | 0.001 | 0.00054 | -.--- |
Could the outburst fail to occur?
Back to top
Visibility map
Back to comments on data in trail table
Computer models:
Jeremie Vaubaillon, IMCCE
Ye and Wiegert (2014)
Mikhail Maslov
Meteor shower/outburst:
Peter Jenniskens (includes extensive
summary of main work done during the decade since the comet's discovery)
International Meteor Organization
NASA Science News
IAU MDC meteor shower 451 CAM Camelopardalids
Comet:
209P/LINEAR (Seiichi Yoshida)
209P/LINEAR (Gary Kronk)
209P image (NASA/MSFC/Bill Cooke)
Rob McNaught's discovery of cometary activity in 2004: this object was
originally known as near-earth asteroid 2004 CB
JPL Small-Body Database Browser
Minor Planet Center (includes observations)
International Meteor Organization home page
Armagh Observatory home page
Last revised: 2014 May 22nd by David Asher with input from Rob McNaught
Last Revised: 2014 May 22nd |