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Special Notice #243: Pre-SN 2011dh images of M51 requested

June 7, 2011: Iair Arcavi and Avishay Gal-Yam (on behalf of the Palomar Transient Factory) write:

"[The discovery of SN 2011dh in M51] (see AAVSO Special Notices #241 and #242) is a very exciting scientific discovery, to which amateurs can further significantly contribute! We at the Palomar Transient Factory seek more image data of M51, obtained between May 30 and June 2, 2011. So, if you have imaged this galaxy using a telescope and a digital camera, your data may be very useful to this project!

"Helpful data would be:
- images of M51 between 2011 May 30 and June 2
- only if it has an accurate time stamp

"In case such data exist, please send the raw images, specify the filter(s) used, and if possible also send images of the same field taken with the same instrument and telescope before May 30, to:

"Your help could be crucial for great scientific discoveries! We will not use any data without permission, and will of course credit all useful images. Many thanks."

Coordinates of M51 (NGC 5194): RA 13 29 52.698   Dec +47 11 42.93 (J2000.0)

This AAVSO Special Notice was compiled by Elizabeth O. Waagen.



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