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See the 11-day-old Moon occult Epsilon Capricorni on 27 September

Magnitude +4.5 star Epsilon (ε) Capricorni is occulted by the dark limb of the 11-day-old waxing gibbous Moon whilst highest in the southern sky of the UK on the night of Sunday, 27&September. The event is visible from the entire British Isles, starting close to 21h UT with reappearance some 1.3 hours later; times for specific locations are given below. This graphic shows the event’s progress as seen from Plymouth and Inverness, clearly demonstrating the parallax effect of geographical latitude. BAA illustration by Ade Ashford.

If the night of 27 September is clear, observers across the British Isles get an opportunity to witness a naked-eye star slip behind the waxing gibbous Moon while the pair are highest in the southern sky. Magnitude +4.5 star Epsilon (ε) Capricorni lies on the eastern side of the constellation Capricornus. The precise time and duration of the star’s disappearance depends on where you live in the UK, which is summarised for a widespread list of locations in a table at the bottom of the page.

Observers in London will see the disappear at the darkened limb of the 11-day-old Moon shortly after 10:12pm BST (21:12 UTC) and reappear at the bright lunar limb almost 79 minutes later. For a skywatcher in Edinburgh, the star's corresponding disappearance and reappearance times are a few seconds after 10:10pm BST (21:10 UTC) and shortly before 11:25pm BST (22:25 UTC), respectively.

While ε Capricorni's disappearance will be an easy spectacle to follow in a small telescope, the star’s reappearance at the bright lunar limb – between Mare Marginis and Mare Smythii – will be more of a challenge, plus the Moon will be lower in the south-southwest. As with all occultation observations, it pays to be setup and scrutinising the Moon five minutes before the predicted times, particularly if you live some distance from your nearest location listed below.

If you have the stamina to stay up after ε Capricorni's reappearance, magnitude +4.7 star Kappa (κ) Capricorni also disappears behind the Moon's dark limb at 1:47am BST (00:47 UTC) on 28 September for Londoners, or four minutes earlier for those in Edinburgh. Note that the Moon will be very low in the southwest at this time.

LocationOccultation disappearance (UTC)Occultation reappearance (UTC)
Cork21h 00.9m22h 18.6m
Galway21h 01.3m22h 17.4m
Dublin21h 05.0m22h 21.6m
Plymouth21h 05.1m22h 25.6m
Armagh21h 05.2m22h 20.7m
Pembroke21h 05.7m22h 24.1m
Belfast21h 06.2m22h 21.7m
Douglas21h 07.8m22h 23.9m
Cardiff21h 07.9m22h 26.6m
Oban21h 07.9m22h 21.7m
Liverpool21h 09.4m22h 26.4m
Inverness21h 09.9m22h 22.9m
Carlisle21h 10.1m22h 25.8m
Southampton21h 10.2m22h 29.4m
Edinburgh21h 10.3m22h 24.9m
Birmingham21h 10.4m22h 28.3m
Leeds21h 11.3m22h 28.1m
Newcastle upon Tyne21h 11.8m22h 27.5m
Kirkwall21h 11.9m22h 23.7m
Aberdeen21h 12.1m22h 25.8m
London21h 12.2m22h 30.9m
Cambridge21h 12.9m22h 31.0m
Lerwick21h 14.1m22h 25.2m
Norwich21h 14.6m22h 32.3m
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