The June Bootid Meteor Shower is visible each year between 26 June and 2 July, typically peaking on 27 June. This meteor shower if highly unpredictable in nature, with most years producing very few meteors, but the shower occasionally having peak years, in which hundreds of meteors are visible each hour; the most recent of such peak years happened in 1998, with the three peaks prior to that happening in 1927, 1921, and 1916. The shower has a radiant point (point from which the meteors appear to radiate) in the constellation of Boötes, close to the North Pole, making the shower possible to spot from anywhere in the Northern Hemisphere, but hard to see in the Southern Hemisphere. Unfortunately, this year peak activity comes only a few days after the Full Moon on 24 June, which means that good observation of the meteors may be hampered by the brightness of the Moon.
Meteor showers are thought to be largely composed of material from the tails of comets. Comets are composed largely of ice (mostly water and carbon dioxide), and when they fall into the inner Solar System the outer layers of this boil away, forming a visible tail (which always points away from the Sun, not in the direction the comet is coming from, as our Earth-bound experience would lead us to expect). Particles of rock and dust from within the comet are freed by this melting (strictly sublimation, transforming directly from a solid to a gas due to the low pressure on it's surface) of the comet into the tail and continue to orbit in the same path as the comet, falling behind over time.
The June Bootids Meteor Shower is caused by the Earth passing through the trail of comet 7P/Pons-Winnecke, where it encounters thousands of tiny dust particles shed from the comet as its icy surface is melted (strictly sublimated) by the heat of the Sun. 7P/Pons-Winnecke visits the Inner Solar System every 6.37 years, most recently in 2015, and last came close to the Earth on 1927.
7P/Pons-Winnecke was discovered on 12 June 1819 by French astronomer Jean-Louis Pons, then based at Marseilles Observatory, and rediscovered by Friedrich August Theodor Winnecke at Pulkovo Observatory near Saint Petersburg. The designation 7P/Pons-Winnecke implies that it was the seventh comet discovered (7/ - strictly speaking people had been observing comets for thousands of years, but it was not until the mid-eighteenth century that it was realised that they were predictable objects that returned cyclically), that it is a periodic comet (P - again, most comets are periodic, but the term 'periodic comet' is reserved for those with periods of less than 200 years, since these can be reliably predicted), and that it was discovered by Pons and Winnecke.
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