June Bootids

The June Bootids are a meteor stream, which has its radians in the northern region of the constellation Bootes. They are active from June 22 to July 2. The maximum of the June Bootids, which is achieved on June 27, has a variable rate of meteors.

When mother body of this meteor stream is the comet Pons- Winnecke. Beginning of the 20th century, the railway of Pons- Winnecke was modified so by the gravitational forces of Jupiter, that the comet orbit of the Earth's orbit was very close. This resulted in 1916, 1921 and 1927, an increased rate of meteors as the Earth moved by freshly liberated dust of the comet. Subsequently, the comet ride away again from the Earth's orbit, so that the meteor did not meet the earth.

However, the June Bootids surprisingly appeared again in 1998 and 2004. Then observed meteors come from previously released dust, and their orbits are very different from the present-day orbit of Pons- Winnecke.

Usually the ZHR of the June Bootids is so low that the meteor stream is hardly noticeable. In 1998 the ZHR rose for a short time to approximately 100 meteors / hour, while the ZHR rise in 2004 to about 50 meteors / hour.