Eclipse of the Hunter's Moon

by Matt Allard and Philip Steffey

 

In the evening of October 27, 2004, we set up Steffey's 80 mm refracting telescope just outside the southeast entrance to the Mickens Computer Laboratory and the science lecture hall, with an Orion video camera connected to a 13-inch TV monitor, in order to exhibit the phases of the total lunar eclipse to interested students and faculty. To our pleasant surprise, local amateur astronomer Tony Viviano joined us with his 16-inch Meade Dobsonian reflector. Now these events can be viewed well with only the naked eye or binoculars, but most people overlook them and our strategy was to draw attention with our instruments to an almost perfectly timed one. For the entire evening the sky was mostly very clear.

The full Moon, low in the east, entered the Earth's penumbral shadow at 8:06 P.M. EDT, but we did not expect to see anything of this and therefore prepared to observe beginning at 8:45. Our telescopes and the video equipment are shown in the first pictures group following this text. Almost immediately the video image of the Moon revealed penumbral shading though it wasn't evident to the naked eye at our site until after 9:00, probably due to glare from parking lot lights. The umbral partial eclipse began at 9:14, but the video camera didn't resolve the umbra's leading edge from penumbra very well so several minutes passed till its onset was definite. Thereafter, in an hour the Moon changed from ordinary except for a flat east limb to a tiny sliver of light on a leaden-yellowish disc. Some of this phase is reproduced from videotape in the second group of pictures following. Up to a dozen visitors at a time watched it on the TV monitor and/or in Tony's big 'scope. Another local amateur stargazer we enjoyed seeing, Bill Brown, was among them.

The late partial phases revealed that the Orion camera was incapable of registering the shadowed lunar disc and still sunlit portion well. When total eclipse began at 10:23, the medium-dark Moon (for an eclipse) barely showed on the monitor and had no details that still frames could reproduce. The small telescope was reconfigured then for direct visual observing at very low power, revealing a burnt-orange hue. The final set of pictures begins at the end of totality, around 11:45, and ends with early post-total partial phases.

 

 

Picture Descriptions:

Picture A: The 80 mm refractor with Orion video camera, outside the lobby of the Mickens Computer Laboratory and science lecture hall. A 13-inch TV monitor, just inside the lobby, shows the full Moon shortly before the Oct. 27-28, 2004 eclipse began.

Picture B: Tony Viviano with his 16-inch Dobsonian reflector, Mrs. V. and daughter.

Picture 0: At 9 P.M. EDT, penumbral shading was conspicuous in the right quarter of the Moon's video image but not yet to the naked eye.

Picture 1: The umbral partial eclipse began at 9:14 P.M. The video camera did not sharply separate the deep penumbra so this image somewhat exaggerates the umbra¹s incursion. Notice the appearance of Tycho, the dark-ringed crater in the far left of the sunlit disc, and its three prominent rays, due to penumbral shading.

Picture 2: By 9:30 P.M. the umbra was well-defined.

Picture 3: Image at 10 P.M., approximately 20 minutes before the beginning of total eclipse. A shortcoming of the camera is clear here and in Picture 2: it could not show the disc in the umbra when set for a good exposure of the still sunlit part. Unaided eye views did.

Picture 4: A few minutes before totality began. The disc in the umbra isnow visible but just above the camera's thermoelectric noise level, so detail is lacking.

Picture 5: Total eclipse over, near 11:50 P.M. Somewhat better determination than naked eye or binoculars views.

Picture 6: Five minutes after Picture 5, post-totality partial eclipse was clearly underway.

Picture 7: Last video image at approximately 12:15 A.M. As before totality, the disc in the umbra is obscured by the exposure level of the sunlit part.

 

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