Damoсloid asteroid 2013 UQ4 showed cometary activity

Damocloid asteroid 2013 UQ4 was discovered in the autumn of 2013. Observations carried out by A. Novichonok and T. Prystavski on May 07.82, 2014 revealed  cometary activity of this object. In addition, this newly discovered comet is expected to be bright in the mid of summer, attaining magnitude up to 7 mag and having good conditions for observations in the Northern Hemisphere. 2013 UQ4 will pass perihelion  on July 5^th, 2014 at a distance of 1.08 a.u. being close to Earth at the same time (0.31 a. u. on July 10^th). Close approach to Earth at the perihelion and also sufficiently large nucleus make this comet shine bright throughout the hot summer nights!

A. Novichonok and T. Prystavski  discovered cometary features of  Damocloid asteroid 2013 UQ4 observing it low in the morning sky (at altitude 20 deg) using a 50-cm remote telescope (MPC=Q62, iTelescope observatory. Siding Spring, Australia). Comet has large and very diffuse asymmetric coma with approximately 1.5' diameter, no tail and total magnitude near 13.5m. Inner well condensed coma is 25'' diameter. Photometric nucleus is well condensed and shifted relative to the center of coma.

  Object 2013 UQ4 was discovered on October 23^rd, 2013 at 18.5 mag (68-cm telescope, Catalina Sky Survey). Observers did not admit any cometary activity during several months. Absolute magnitude H=12.9 which is proof that object is actually large with diameter of about 7-15 km. At the end of January, 2014 Damocloid asteroid 2013 UQ4 ceased to be observed due to conjunction with the Sun. Now it is in the sky again revealing clear cometary activity.

Visually comet can be observed already, but the conditions are expected to get better. In May, 2014 comet can be found in the morning sky in constellation Cetus. In June it will move up north floating constellations Pisces and Andromeda. 2013 UQ4 will brighten up to 13.5-11.5 mag during May, attaining 8–9 mag by the end of  June. In time of perihelion passage (June 5^th, 2014), when comet will be at maximum brightness (7 mag predicted) best observation conditions will be just for northern observers. On July, 10^th comet will have close approach to Earth (0.31 a. u.), moving fast in the constellation Andromeda, Lacerta, Cepheus, Draco and Boötis (sky motion 7 deg per day). Reaching maximum brightness about July 10, C/2013 UQ4 begin to weaken rapidly -  (10 mag at the beginning of August and 13 mag at the beginning of September).

Watch comet C/2013 UQ4 visually and submit your observations to CometBase!

Authors - T. Prystavski, A. Novichonok