Dear all

The report below has been sent to the CBAT but for those who want to
further follow this comet there might be some useful early information
here.

cheers

Jure Skvarc

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Periodic comet P/2010 H2 (Vales)

We observed the comet P/2010 H2 (Vales) in moonless conditions on May
1, 2010 using B, V and R photometric filters, as well as with the
clear filter on the 0.6 m, f/3.3 Cichocki telescope at the Crni Vrh
Observatory. The exposures, all of 8 minutes duration, were tracked on
the comet and obtained between 19:46 and 20:31 UT. The pixel scale was
0.93 arcseconds.

All images exhibit slightly asymmetrical coma. On the highest SNR
image, taken with the clear filter, the coma has a 1.9 x 2.0 arcminute
axis length. The axis of symmetry is at PA = 134 +- 5 degrees,
measured from the central condensation towards the middle of the wider
part of the coma. No obvious tail or any other structure is been seen
on any od the unprocessed images, regardless of contrast stretching or
false colouring of the images.

To resolve details inside the coma the images were processed with the
wavelet decomposition tool of the IRIS software. Rather remarkable
details become visible. There is a blob of ejected material at 14 +-
1 arcseconds (projected distance from the comet 22000 km) at PA of 215
+- 3 degrees. Images taken with V, R and clear filters show a
distinct spiral structure emanating from the comet at a single spot
located at the PA = 240 +- 5 degrees. Nothing like this is seen on
the B filter image. Especially the clear filter image is very
suggestive of the explanation that we are looking at the dust ejection
process. The stream of material is emanating from the comet nucleus
and is aligned along the line of sight with a spiral of 1 arc-minute
(93000 km at the comet distance) diameter.

Rotational gradient filtering with angles of 30 or 45 degrees reveals
basically the same features but with lower contrast.

False-color images, on which this analysis has been made, are
accessible at http://www.observatorij.org/images/10h2_d01.html

Jure Skvarč
Črni Vrh Obsevatory