“Meteor showers” are not expected in October

The Draconid meteor shower with a radiant in the constellation Draco is considered the youngest known: the comet Giacobini-Zinner (21P/Giacobini-Zinner) that formed it was able to approach the Earth a little more than a century ago. The swarm of meteor particles ejected by it during this time did not have time to disperse significantly around its orbit and move away from the comet nucleus. Therefore, the period of activity of the shower is quite short (approximately from October 5 to October 11), and its bursts are observed when the comet passes close to our planet.

This happened, for example, on October 9, 1933, when the intensity of the Draconids reached two thousand meteors per hour. Recall that “meteor showers” are phenomena during which this number exceeds a thousand. The burst of activity of the shower on October 9, 2018, slightly “fell short” of this status when some observers reported 700–800 “falling stars” within an hour. That year, comet Giacobini-Zinner flew at a distance of 0.392 AU (58.6 million km) from Earth. Now it is located in a remote part of its orbit from the Sun, which means that we are not in danger of “meeting” either with it or with the dense part of the meteor swarm generated by it. Therefore, media reports about the “October meteor shower” should not be believed.

The “almost shower” of the Draconid in October 2018 also looked quite impressive. Source: Getty Images

But even with the comet’s next return in 2025, it will not come close enough to us, and astronomers do not expect significant activation of the Draconids during this period. Its appearance looks much more promising in 2031, when on September 4, the distance between the Earth and the “tailed star” will be 0.55 AU (82 million km). It won’t come that close to us until the autumn of 2058.

It is very convenient to observe Draconids in our latitudes; their radiant does not go beyond the horizon on the territory of Ukraine. This shower is also characterized by the fact that the rate of entry of its meteor particles into the earth’s atmosphere is relatively low (only 20 km/s). Consequently, their kinetic energy, which then turns into heat and light due to braking in the air, is relatively small. In addition, the density of these meteors is also one of the lowest — 4-5 times less than the density of water. That is, in order to create a meteor phenomenon visible to the naked eye, a particle of cometary matter should be large enough. Therefore, bright, remarkable “falling stars” in the Draconid shower are rare.

On autumn evenings in our latitudes, the Draconid radiant is located approximately 50° above the western part of the horizon, to the right of the bright Vega (α Lyra). It is in this direction that everyone who wants to see the “fiery greetings” from the comet Giacobini-Zinner should look. At the peak of the shower’s activity, their zenith hourly number may exceed 20. On the night of October 9–10, the Moon in Kyiv will rise at about 2 o’clock and will almost not interfere with observations.

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