We present optical and near-infrared ( IR ) photometry and near-IR spectroscopy of SNÂ 2004am , the only optically detected supernova ( SN ) in MÂ 82 .
These demonstrate that SNÂ 2004am was a highly reddened type II-P SN similar to the low luminosity type II-P events such as SNe 1997D and 2005cs .
We show that SNÂ 2004am was located coincident with the obscured super star cluster MÂ 82-L , and from the cluster age infer a progenitor mass of 12 ^ { +7 } _ { -3 } M _ { \odot } .
In addition to this , we present a high spatial-resolution Gemini-N K -band adaptive optics image of the site of SNÂ 2008iz and a second transient of uncertain nature , both detected so far only at radio wavelengths .
Using image subtraction techniques together with archival data from the Hubble Space Telescope , we are able to recover a near-IR transient source co-incident with both objects .
We find the likely extinction towards SNÂ 2008iz to be not more than A _ { V } \sim 10 .
The nature of the second transient remains elusive and we regard an extremely bright microquasar in MÂ 82 as the most plausible scenario .