* Astronomy

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RE: Draconid meteor shower

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Draconids meteor maximum in the constellation at Draco is at 12:00 UT, 8th October, 2016.

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Draconids meteor maximum in the constellation at Draco at 16:00 UT, 8th October, 2014.

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Draconids 2014: prediction of activity

In 2014 the Earth is expected to encounter to 1900 trail. This trail is "verticalised", and his center composed of particles ejected at the perihelion of the comet 21P, doesn't come very close to the Earth, but intersects its orbit 0.61 day after the Earth passes the point of intersection. However the particles ejected 90 days before the perihelion pass at 0.0050 AU from the Earth at 22:42 UT on 6 October.
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Draconids meteor maximum in the constellation at Draco at 10:00 UT, 8th October, 2013
The meteor shower is active from the 2nd to the 16th October.

ZHR: 20.0
Velocity: 23.7km/s
Radiant (2000): RA=17.6h/263° Dec=55.8°

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Title: Radar Observations of the 2011 October Draconid Outburst
Authors: Quanzhi Ye, Peter G. Brown, Margaret D. Campbell-Brown, Robert J. Weryk

A strong outburst of the October Draconid meteor shower was predicted for October 8, 2011. Here we present the observations obtained by the Canadian Meteor Orbit Radar (CMOR) during the 2011 outburst. CMOR recorded 61 multi-station Draconid echoes and 179 single-station overdense Draconid echoes (covering the magnitude range of +3 <= MV <= +7) between 16-20h UT on October 8, 2011. The mean radiant for the outburst was determined to be a_g = 261.9° ±0.3°, d_g = +55.3° ±0.3° (J2000) from observations of the underdense multi-station echoes. This radiant location agrees with model predictions to ~1o . The determined geocentric velocity was found to be ~10-15% lower than the model value (17.0 - 19.1 km s^-1 versus 20.4 km s^-1), a discrepancy we attribute to undercorrection for atmospheric deceleration of low density Draconid meteoroids as well as to poor radar radiant geometry during the outburst peak. The mass index at the time of the outburst was determined to be ~ 1.75 using the amplitude distribution of underdense echoes...

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Title: The 2011 October Draconids outburst. I. Orbital elements, meteoroid fluxes and 21P/Giacobini-Zinner delivered mass to Earth
Authors: Josep M. Trigo-Rodríguez, José M. Madiedo, I. P. Williams, Joan Dergham, Jordi Cortés, Alberto J. Castro-Tirado, José L. Ortiz, Jaime Zamorano, Francisco Ocaña, Jaime Izquierdo, Alejandro Sánchez de Miguel, Jacinto Alonso-Azcárate, Diego Rodríguez, Mar Tapia, Pep Pujols, Juan Lacruz, Francesc Pruneda, Armand Oliva, Juan Pastor Erades, Antonio Francisco Marín

On October 8th, 2011 the Earth crossed the dust trails left by comet 21P/Giacobini-Zinner during its XIX and XX century perihelion approaches with the comet being close to perihelion. The geometric circumstances of that encounter were thus favourable to produce a meteor storm, but the trails were much older than in the 1933 and 1946 historical encounters. As a consequence the 2011 October Draconid display exhibited several activity peaks with Zenithal Hourly Rates of about 400 meteors per hour. In fact, if the display had been not forecasted, it could have passed almost unnoticed as was strongly attenuated for visual observers due to the Moon. This suggests that most meteor storms of a similar nature could have passed historically unnoticed under unfavourable weather and Moon observing conditions. The possibility of obtaining information on the physical properties of cometary meteoroids penetrating the atmosphere under low-geocentric velocity encounter circumstances motivated us to set up a special observing campaign. Added to the Spanish Fireball Network wide-field all-sky and CCD video monitoring, other high-sensitivity ½" black and white CCD video cameras were attached to modified medium-field lenses for obtaining high resolution orbital information. The trajectory, radiant, and orbital data of 16 October Draconid meteors observed at multiple stations are presented. The results show that the meteors appeared from a geocentric radiant located at R.A.=263.0±0.4 deg. and Dec.=+55.3±0.3 deg. that is in close agreement with the radiant predicted for the 1873-1894 and the 1900 dust trails. The estimated mass of material from 21P/Giacobini-Zinner delivered to Earth during the six-hours outburst was around 950±150 kg.

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Draconids 2012: visual data quicklook

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Update:
According to Bill Cooke, of NASAs Meteoroid Environment Office, this years Draconid meteor shower produced a major outburst of 1000 meteors per hour (CMOR radar rates), just after 16:00 UT.

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This years Draconid meteor shower is predicted to be strong, as the earth passes through a dense dust stream left by an old passage of comet 21P/Giacobini-Zinner.