简而言之，今年地球不与庞斯-温尼克彗星的任何年份抛射物相遇，六月牧夫座流星雨的活动将会十分微弱
June Bootids 2009: prediction of activity
[size=-1]to the list of predictions
Fig. 1. Space-temporal projection of June Bootids trails parts onto their minimal distance to the Earth orbit passages.
Fig. 2. Difference between the solar longitudes of the minimal distance passge points and timings of the Earth passing the points of the same solar longitudes on its own orbit (axis X).
[size=-1]The red rhombus approximately restricts the area where the particles pass close enought to the Earth's orbit roughly in the same time with the Earth itself.
Fig. 3. Detailed space-temporal projection of June Bootids trails parts onto their minimal distance to the Earth orbit passages in 2009.
Fig. 3. Detailed space-temporal projection of June Bootids trails parts onto their minimal distance to the Earth orbit passages in 2009.
2009
No encounters with trails, activity is not expected.
2010
In 2010 two cases of activity are possible, but probability of both of them is not high.
First, in 2010 the Earth's orbit will intersect the resonant cloud of 19 century trails, which produced June Bootids activity on June 23-24 in 2004. However, in 2010 cloud particles pass farther from the Earth's orbit, and the encounter itself will occur a couple of weeks later than in 2004. So neither direct not vertical encounters are not found for this case and we could cunclude that expected activity is zero. Still we recommend the observers to make observations during the period of June 23-25, and especially during the period of 23-24.06.2010 14-4 UT, as the dust cloud is quite perturbed and we can't exclude that a very weak activity (with ZHR up to 5 meteors) will occur in the given period. Also some other old trails can be present in the resonant area of space. Unfortunately, the almost full Moon will significantly decrease observing conditions.
Second, for 2010 the red rombus contain one of young regular stream trails (fig. 2). It intersects the Earth's 8.24 days before the Earth passes the intersection point. This is the 1921 trail, the parameters of vertical encounter are the following: Vej=99.29 m/s, fM(FMD)=0.715, sol.long.=92.802° (June 24, 13:46 UT). Due to very high ejection velocity visual activity from this encounter is not possible, but one can try to catch radioactivity of the shower around the given time, although here the probability seems to be very low too. Theoretical radiant^: RA=204.2°, Dec=+50.4°, v=13.3 km/s.
A number of other researches are also found encounters with resonant 19 century trails in 2010. For example, in [4] encounters with 1819, 1825, 1830 and 1836 June Bootid trails are listed. The timings are between June 23 22:40 UT and June 24 3:53 UT. However, the distance between those trails and the Earth will be large - -0.03834 - -0.04406 AU, so activity is not expected from those encounters.
References
1. "Comet's dust 2.0" program by S. Shanov and S. Dubrovsky. [Used for orbital computations.]
2. Information from Gary W. Kronk's page http://www.maa.agleia.de
3. Lyytinen E, van Flandern T. "Predicting the strength of Leonid outbursts", 2000, Icarus, P. 158-160.
4. Jenniskens P. Meteor showers and their parent comets, 2006, 780 p. | 
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