A 2017 Eclipse Megamovie: Outreach and Science H.S. Hudson 1,2, S. McIntosh 3, S. Habbal 4, L. Fletcher 2, I. Hannah 2, M. Hendry 2 1 SSL, UC Berkeley, 2 University of Glasgow, 3 HAO, 4 University of Hawaii, Fig. 3. Image from the 2006 eclipse in Turkey (© 2006 Kolíbal, Druckmüllerová, & Druckmüller; see their Web site).This eclipse preceded the 2017 eclipse by ~11 years and gives a feeling for the brightness of the corona. The composed image includes 102 exposures, ranging from 1/1000 to 8 s, made with Maksutov-Cassegrain mirror lenses and 8.2 Mpix or film readout. SYNOPSIS: The 21 August 2017 total eclipse has wonderful circumstances (Figs.1, 4) and possibly good summer weather (Fig. 2). See also Poster P23.21 (Byrne et al.) and S. Habbal presentations and at the SPD Business Meeting. In Fig. 3 we show one of the spectacular Druckmüller eclipse images the Turkey eclipse 11 years prior. We suggest taking advantage of the expected huge turnout of observers all along the path to make an unprecedented “megamovie” representation of the phenomena The Data: We would expect hundreds, if not many thousands, of observers at sites all along the path of totality (Fig. 1). Many will have good optics and CCD cameras (12 Mpx now, who knows what by 2017?). All of the frames that each camera captures can be astrometrically calibrated via techniques at astrometry.net if stars are visible. Figs. 1 (above) and 2 (right): the path of totalilty across the U.S., and a global mean weather map for August. Fig. 5. Stereographic view of the whole eclipse from eclipse-maps.com The Science: We view this activity mainly as an outreach function, to encourage as much participation and learning as possible. A part of this encouragement is to have flashy science possibilities. Some of ours are: To make a long movie of coronal dynamics right down to the chromosphere. Could we have 10 6 frames? On an overview version, we could add the observers’ names. To observe exotic aspects of the corona, such as its 3D structure via rotation, jets and filament dynamics, comets near the surface and CMEs if they should occur. To revisit the Eddington experiment, almost for the first time with CCD detectors.This would use the best frames, astro-metrically calibrated (see the box on the right for the stars). The Astrometry Software: For image coalignment, especially for the Eddington experiment, we need special software. It’s available on astrometry.net – see Lang et al. AJ 139, 1782 (2010), and Lang & Hogg, astro-ph (2011) for an especially relevant and charming example of its use. Please note the Business Meeting discussion, led by Shadia Habbal, Monday evening Nu Leo Regulus Leo The Relativity: The gravitational deflection of starlight underpins the modern science of gravitational lensing. Historically, a 1919 eclipse visible in Brazil and Principe (Africa) led to Eddington’s confirmation of the Einstein prediction. Radio techniques have superseded ground- based optical eclipse observations for this purpose, but the deflection (of order one arc sec) is easily within the range of modern amateur telescopes equipped with CCD cameras – has this ever been done before? The 2017 star field includes Regulus!