Draconids
Meteor shower Giacobiniden |
|
---|---|
activity | |
Beginning | October 6th |
maximum | 8th October |
The End | October 10th |
Radian position | |
RA | 17 h 28 m |
DE | + 54 ° |
ZHR | var (1–10), outbreaks every 13–39 years |
Population index | 2.6 |
geocentric speed |
20 km / s |
The meteor shower of the Draconids , also called Giacobinids after its comet of origin , is active from October 6th to October 10th and reaches its maximum on October 8th. The Radiant is located in the "head" of the constellation Dragon , that of Central Europe from circumpolar is.
Usually only 2 meteors per hour can be seen at maximum, but in some years dozens. In addition, there are outbreaks every 13–39 years with even higher fall rates.
origin
Because of the mostly low fall rate, the meteor swarm could only be assigned to a parent comet by M. Davidson in 1915. It is the short-period comet 21P / Giacobini-Zinner with an orbit period of 6.5 years, the perihelion of which almost falls on the earth's orbit. Around October 8th the earth flies through this point and parts of the dust left by the comet burn up in the earth's atmosphere as shooting stars. If the tail star is still close to the perihelion while the earth is moving through the particle cloud of the comet there, the higher dust density leads to particularly intense meteor streams. Historically, this phenomenon occurred about every 13 years, which corresponds to about two periods of Giacobini-Zinner rotation. This resulted in an increased fall rate of meteors in 1933, 1946, 1985 and 1998 .
Similar influences and orbital disturbances by Jupiter occur not only with the comets of the Jupiter family , but also with other meteor streams such as the Quadrantids and Ursids .
history
The most spectacular events occurred in 1933 and 1946, when a Zenithal Hourly Rate (ZHR) of approximately 10,000 meteors per hour was observed - i.e. H. in a favorable location about 3 per second. In 1985 and 1998 the ZHR reached a value of over 500 meteors per hour. In 2005, a ZHR of 150 meteors per hour was registered by means of radar, while visually at least 40 shooting stars per hour were sighted.
On October 8, 2011 between 6pm and 11pm CEST , a significantly increased fall rate was observed again. The ZHR reached a value of approximately 250 meteors per hour. Because of the almost full moon , which brightened the sky, visually significantly fewer meteors could be seen. A year later, on October 8th, there was another increased meteor rate. A ZHR of about 320 meteors per hour was observed in the evening hours.
Web links
- Draconids at meteorshowersonline.com
supporting documents
- ↑ IMO Meteor Shower Calendar 2020 , accessed April 16, 2020
- ↑ "Draconids (Giacobinids)". Meteor Showers Online, accessed on January 6, 2018 ( Memento from August 7, 2008 in the Internet Archive )
- ^ Orbit data: Draconids in the Small-Body Database of the Jet Propulsion Laboratory (English).
- ^ Rainer Arlt: "Summary of 1998 Draconid Outburst Observations", Journal of the International Meteor Organization, vol. 26, no. 6, p. 256-259 1998, http://articles.adsabs.harvard.edu//full/1998JIMO...26..256A/0000256.000.html
- ↑ The 2005 Draconid outburst (PDF; 380 kB), accessed on September 30, 2011
- ↑ draconids.seti.org: 2011 Draconids: storm or just an outburst? by J. Vaubaillon - IMCCE , accessed October 14, 2018
- ↑ Draconid outbreak 2011? Sternenbote 2011 issue 10
- ↑ imo.net: Draconids 2011 campaign , accessed on September 3, 2019
- ↑ Draconids 2012: visual data quicklook ( memento of October 24, 2016 in the Internet Archive ), accessed on October 9, 2012