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2013 October 13, 01:23 UT Newberry Star Park • Easton Newberry Sports Complex • Newberry, Florida Lat. 29°40.15' N, Long. 82°36.05' W, Elev. 83 ft (25 m) Summary: The dark and faint eastern limb (edge) of a first quarter moon moves eastward on the sky (toward left in this gif video) to occult (cover up) the third magnitude star Beta Capricorni, which remains stationary. The western sunlit (bright) section of the Moon is at upper right and overexposed so images can show the earthlit (dark) limb of the Moon approaching the star. The bright star is Beta Capricorni with a much fainter 8th magnitude star to the lower left of Beta. Click image for 2x larger version
mpg movie • mov movie • avi movie (May or may not work depending on your browser and add-ons) Observing Notes: Images taken at Alachua Astronomy Club's (AAC)International Observe the Moon Night 2013 (InOMN). Principle goal was to show visitors the Moon and not to observe the fortuitous occultation! Camera/telescope was set up to show a large lunar image on a 40 in. LCD TV screen. This allowed about a dozen people to watch the occultation in real time. For those who remained at this event until after nine o'clock, this was a rare opportunity for the public to view a stellar occultation! Photos were taken as a byproduct with little care given to timing, focus, exposure or tracking (poor due to unfortunate misalignment of polar axis)! However, the exposures were adjusted to overexpose the bright limb of the Moon so observers could also see the dark limb on the TV screen. The dark limb is also obvious in the photographs. Predicted time of dark limb occultation was 9:21 p.m. EDT, 2013. Oct. 12 (01:21 UT, Oct. 13). The seven frames used to make video begin at approximately 9:15:16 p.m. EDT (21:15:16 UT) and end 5m 45s later at 9:21:01 p.m. EDT (01:21:01 UT). About the Star: Beta Capricorni (Dabih = 9 Cap = HD 193495 = SAO 163481 = TYC 5753-2281-1, abbrev. Beta Cap) is a wide visual double (mag. +3.05) with a fainter star (HD 193452 = TYC 5753-2282-1 = STFA 52; mag. +6.09), 3.4 arc minutes west of Beta Cap. We also watched the occultation of this second star, which occurred about 10 minutes before the occultation of Beta Cap itself. Therefore, HD 193452 is already hidden by the Moon in this video. (Photos also taken but not processed.) However, looking carefully, one can see a still much fainter star (HD 193543 = SAO 163486 = TYC 5753-2283-1; mag. +8.78) trailing Bet Cap 3.75 arc minutes to the southeast. The distances of the pair from the Sun are about 344 and 314 light years respectively. They are likely an optical double and not related. However, Beta Cap is itself a resolvable double (3.5 arc min separation) consisting of +3.05 and +6.09 magnitude stars. The stars are about 21,000 light years apart. If actually physically related, the orbit period would be roughly 700,000 years. Both stars (Beta 1 and Beta 2) are also apparently multiple. Photo Details: TeleVue NP 127mm APO, f/5.2 on Equatorial Driven Mount with Televue 4x Powermate givng effective f/21. Camera: Canon EOS 5D Mark II. Seven frames with exposures of 0.7 sec each with equiv. ISO 1600. Sky Transparency Good but Seeing Mediocre. Temp. ~65°F (18°C), Humidity ~80%. Frames processed in Corel PaintShop and trimmed from original. |
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Last updated 2015 December 10