Each year at the end of June, one of the most variable and mysterious meteor showers occurs – the June Boötids. This “meteor shower” occurs during the summer solstice, so the nights are short, although pleasant and warm after hot days. And, as the period of its activity approaches, let’s talk a little about what to expect from observations.
Where does a meteor shower originate?
Like most meteor showers, the June Boötids originate from a comet, in this case the short-period comet Pons–Winnecke (7P/Pons–Winnecke), which moves in an elongated elliptical orbit, returning to the Sun every 6.3 years. In particular, astronomers expect it to reappear in the sky in August 2027.
Comet 7P was discovered by Jean-Louis Pons on June 12, 1819, after which it disappeared from astronomers’ view for almost four decades until it was rediscovered on March 9, 1858, by Friedrich August Theodor Winnecke. Thus, the comet “inherited” its name from two of its discoverers from different generations.
As it approaches the Sun, the comet’s gases evaporate, capturing small dust particles. They continue to move along roughly the same trajectory as the comet, gradually dispersing along its orbit. When the Earth crosses this stream, the particles collide with the atmosphere and burn up, and we see a “shooting star” – a meteor. If we trace the trajectories of the meteors backward, they will intersect in a specific area of the sky in the constellation Boötes. This area is called the radiant, and its location gives the Boötids their name.
How intense are the June Boötids?
According to the International Meteor Organization (IMO) calendar, this meteor shower is active from June 22 to July 2, with peak activity expected on June 27. And this is a very favorable time for observations, as the Moon will be in a thin crescent phase.
Generally, the Boötids do not delight observers with their high activity: most often, only 1-2 meteors per hour can be observed. But in 1916, on the night of June 28, English observers witnessed a very powerful meteor shower. In fact, this shower was discovered at that time. Over the next few years, the shower “calmed down,” but in 1921 and 1927, it became highly active again.
In the same year, 1916, experienced observer W. F. Denning, who described the activity of the shower in detail, was able to link the new meteor shower to the comet Pons-Winnecke. Moreover, the comet passed its perihelion almost a year before the increased activity of the “meteor shower.”
The last high activity of this shower was observed in 1998, when up to 100 meteors per hour could be seen. Such variability and unexpected bursts of activity are most likely related to Jupiter’s gravitational influence on both the Pons-Winnecke comet and the trail of dust particles. It is reliably known that from approximately 1869 to 1964, the comet’s orbit changed dynamically, but has stabilized over the last 60 years. Thus, although the IMO’s official forecast predicts low activity, a sudden increase cannot be ruled out.
Where and how to observe?
No one can predict exactly which year will bring the next surge in activity from the June Boötids. It is quite possible that only a couple of meteors will be detected in an hour. But if you still want to try, the best chances are in the evening and early night of June 27 and 28. And, of course, it’s better to leave the city — far away from the city lights.
As soon as the sky gets dark, the radiant point of the shower will be close to the zenith. However, it is precisely in the radiant where you are least likely to see meteors. Choose a section of the sky that is 20°-30° away from it. You will not need a telescope or any other device for observations. But it’s worth taking warm clothes, tea in a thermos, snacks, and a comfortable place to relax — a travel mat or folding chair are perfect. Although, of course, nothing warms and embellishes nighttime observations like the warm company of friends or family.
