Map the Moon During Tomorrow's Lunar Eclipse
This is an AstroAlert from Sky & Telescope.
Please help us accurately map the edge of the Moon by timing occultations of stars during the August 28th total lunar eclipse (Tuesday morning in Hawaii and the western parts of the Americas, and Tuesday evening in Australia and New Zealand). This information is needed to help analyze total and annular solar-eclipse observations to determine solar-radius variations, since the Baily's Beads phenomena recorded during some past solar eclipses are caused by the same lunar features that will cover and uncover stars during the lunar eclipse. Especially needed are video or CCD timings of the occultations, especially of reappearances, and of grazing occultations that occur during the eclipse.
You can calculate predictions for lunar occultations for your observing site using Occult, which is available for downloading for free on the International Occultation Timing Association's lunar-occultations website. Timing methods are also described there.
Maps showing grazing occultations of stars of mag. 9.5 and brighter, with corresponding tables, are in the August 28th eclipse grazes section of IOTA's Asteroidal Occultation website. Especially good are grazes of 7.8-mag. stars, with path #2 (ZC 3282) being a northern limit passing near Redding, CA; n.w. of Boise, ID; near Great Falls, MT; and a short distance n.w. of Moose Jaw, Sask. Derek Breit has an interactive Google map for this graze, allowing you to see the path in great detail.
Another good one is path #7, a southern-limit graze of SAO 165048 passing over n.w. Oregon, s.e. Washington, southern Alberta, and near Saskatoon, Sask. Besides ZC 3282, Derek has Google maps for a graze of 11.1-mag. X182578, whose path passes near Rohnert Park, Beale AFB, and Nevada City, Calif.; and for path #8 (8.6-mag. SAO 165040) a little north of #2. Google maps can be prepared for grazes other than the ones mentioned above on request to either Brad Timerson at btimerson@rochester.rr.com or Derek Breit at breit_ideas@hotmail.com. For example, the paths for two 9.4-9.5-mag. stars pass near San Luis Obispo, Bakersfield, and Ridgecrest, Calif., and Las Vegas, Provo, and Greeley, CO, and others pass near Hermosillo, Las Cruces, El Paso, and Lubbock.
For more information and instructions for reporting your observations, see IOTA's lunar-occultations website:
