Not sure if this is old news, but here is the official announcement. Early images may be useful.
The message below was issued 2011 June 7 as AAVSO Special Notice #243. It is also being distributed to the AAVSO discussion and photometry groups in order to reach the widest audience possible.
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 (
http://www.aavso.org/aavso-special-notice-241) and
#242 (
http://www.aavso.org/aavso-special-notice-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:
ptf11eon@gmail.com
"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)
Elizabeth Waagen, AAVSO
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