C/2011 K1 (Schwartz-Holvorcem) was discovered on 2011, May 26.25 by M. Schwartz and P. Holvorcem with the 0.41-m f/3.75 astrograph + CCD from Tenagra Observatory, Arizona, USA.
P/2011 JB15 (Spacewatch-Boattini) was originally discovered as an asteroid by Spacewatch team using the 0.90-m f/3 reflector + CCD from Kitt Peak, Arizona – USA, on 2011, May 8 and 12, and designated by the Minor Planet Center 2011 JB15.
IAUC nr.9209, issued on 2011, May 20, announced the discovery of a new comet (discovery magnitude 19.7) by the LINEAR survey through their 1.0-m f/2.15 reflector + CCD, on images obtained on 2011, May 14.3 The new comet has been designated C/2011 J3 (LINEAR).
A tumbling comet nucleus with a changing rotational rate has been observed for the first time, according to a new paper by a Planetary Science Institute researcher.
A new bright comet diving into the Sun has been discovered on May. 09 by amateur astronomer Sergey Shurpakov using the images taken by SOHO spacecraft.
CBET nr.2714, issued on 2011, May 07, announced the discovery of a new comet (discovery magnitude 19.7) by the LINEAR survey through their 1.0-m f/2.15 reflector + CCD, on images obtained on 2011, May 04.2 The new comet has been designated C/2011 J2 (LINEAR).
IAUC nr.9206, issued on 2011, May 05, announced the discovery of an apparently asteroidal object (discovery magnitude 19.7) by Alex R. Gibbs on CCD images taken on April 26.3 with the Mt. Lemmon 1.5-m reflector. Gibbs suspected that this object might show slight cometary appearance.
You may have heard the news: Comet Elenin is coming to the inner-solar system this fall. Comet Elenin (also known by its astronomical name C/2010 X1), was first detected on Dec. 10, 2010 by Leonid Elenin, an observer in Lyubertsy, Russia, who made the discovery remotely using the ISON-NM observatory near Mayhill, New Mexico.
It seems the past couple of years have seen a bright Comet McNaught and this year is no different. The 58th comet discovery by Rob McNaught and 74th from Siding Spring Observatory, C/2011 C1 was first seen on February 10th of this year.
For the first time, scientists have found convincing evidence for the presence of liquid water in a comet, shattering the current paradigm that comets never get warm enough to melt the ice that makes up the bulk of their material.