martinastro
Martin Mc Kenna
Global Moderator
Hero Member
Posts: 5182
Maghera, N. Ireland
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« on: June 20, 2010, 04:21:29 pm » |
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We could see some June Boötid activity for the first time since 2004, as four 19th-century dust trails from the meteoroid stream are predicted to encounter the Earth on June 23-24. These were laid down by the shower's parent comet, 7P/Pons-Winnecke, at its perihelion returns of 1836, 1830, 1825 and 1819, and are expected to produce whatever activity they may around 22:40 UT on June 23 and near 00:07, 01:22 and 03:53 UT respectively on June 24. Zenithal Hourly Rates (ZHRs) are uncertain, but may be possibly similar to those seen in 2004, which were ~20-50.
The Moon is at first quarter on June 19, and full on the 26th, which, with the perpetual twilight for UK observers, will make conditions unhelpfully poor. However, checking for whatever takes place is very important this summer, especially as most of the maximum timings fall perfectly for overnight British coverage. Past June Boötid returns, including that with ZHRs of ~50-100 in 1998, the first strong return since 1927, were readily seen from Britain despite the twilight, so if skies are clear, face towards as much darker sky as you can, avoid having the Moon in your view, and hope for the best!
June Boötids are very slow meteors, so should be quite unmistakable, likely emanating from a diffuse radiant in northern Boötes centred at RA 14h56m, Dec +48°, an area well on-view throughout the short nights. Note though that new International Meteor Organization (IMO) video results have suggested some very weak annual Boötid activity has occurred in most recent years, at a level too low to be detected by visual watchers, from a radiant centred notably south of the expected one, near RA 14h24m, Dec +38° on June 23. A few June Boötids could be seen at other times between June 22 and July 2, but remember, there are no guarantees any activity will definitely occur at all. We can but watch and hope. Credit: Alastair McBeath, Meteor Director, Society for Popular Astronomy.
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