A very young core-collapse supernova burst forth on 21st March in the bright Messier galaxy Messier 65, surprisingly the first supernova to be discovered in that galaxy, raising hopes of a spectacular and pretty rare chance for amateur observers to follow its rise to brightness.

Messier 65 showing the type-II supernova shining at 16th magnitude on 7 April. Image credit: Jose Carrillo. Check out a larger image.
 
But supernova 2013am has subsequently disappointed astronomers by holding steady around its 16th magnitude discovery magnitude.

M Sugano from Kakogawa, Japan imaged M65 on 21 March, noticed the 'new star' glowing at magnitude +15.6 and alerted the Central Bureau for Astronomical Telegrams, the official clearing house for astronomical discoveries. The Asiago 1.82-m telescope obtained a spectrum just over 24 hours later, confirming the object was a very young (few days after explosion) type-II supernova, the result of a massive star that has used up all of its fuel and goes out in spectacular fashion.

Meanwhile the Intermediate Palomar Transient Factory (iPTF) had detected the supernova on 22 March using the Oschin Schmidt telescope at the Palomar Observatory, reporting that nothing was detected at the place of the new object on an image taken on 19 March down to a limiting magnitude of +21. All their significant resources swung into action remarkably quickly and efficiently, with the 3m Shane telescope at Lick Observatory, a veteran of confirming supernovae spectrally, obtained a spectrum just 7.8 hours later, the same night in fact, confirming the young type-II classification.

M65 is one of the Leo trio or triplet galaxies along with M66 and NGC 3628. Look for it 2.5 degrees southeast of Chertan (theta Leonis). Check out a larger image.
 
Astronomers professional and amateurs alike homed in on M65, a magnificent spiral galaxy in Leo and one of the famous so-called Leo Trio or Triplet, expecting a rapid and steady increase in brightness. M65 lies 32 million light years away and a classic type-II supernova at maximum light should reach at least twelfth magnitude at maximum brightness and take around 15 days to get there.

But the supernova has stubbornly refused to behave and dashed observers hopes by languishing around magnitude +16. So what's the story? The more observant astronomers looking at the plethora of images coming in of M65 have noticed the supernova lies close or in a dark patch of dust. The spectra obtained show a reddened continuum and a more recent high-res spectrum from the 3.58-m TNG telescope on La Palma shows strong Na D absorption, confirming high extinction or light-loss by dust in M65.

All is not lost though; the supernova is well within range of CCDs on moderate apertures and it's well worth keeping an eye on the galaxy while it's in prime position in the evening sky.

Check out latest images and magnitudes of the supernova.