C/2013 V5 (Oukaimeden)

Lore & Background

The comet was discovered on 12 November 2013 at an apparent magnitude of 19.4 using a 0.5-meter reflecting telescope at the Oukaimeden Observatory. From 5 May 2014 until 18 July 2014, its elongation from the Sun was less than 30 degrees. By late August 2014, it had brightened to apparent magnitude 8, becoming a small telescope and high-end binoculars target for experienced observers. It crossed the celestial equator on 30 August 2014, becoming a Southern Hemisphere object. On 16 September 2014, the comet passed 0.480 AU from Earth. It peaked around magnitude 6.2 in mid-September 2014, though its elongation was only about 35 degrees from the Sun. On 20 September 2014, the comet was visible in STEREO HI-1B. It reached perihelion on 28 September 2014 at a distance of 0.625 AU from the Sun.

C/2013 V5 is dynamically new, having come from the Oort cloud with a loosely bound chaotic orbit easily perturbed by galactic tides and passing stars. Before entering the planetary region (epoch 1950), its orbital period was several million years; after leaving the planetary region (epoch 2050), it will have an orbital period of about 6000 years. Infrared spectroscopy revealed that most of its volatile ices, with the exception of ammonia, are depleted. Spectrography also showed that the relative abundance of ethane and methanol increased at the start of September 2014, suggesting the ices comprising the comet are heterogeneous.

Reader's Guide

C/2013 V5 (Oukaimeden) holds significance as a dynamically new comet from the Oort cloud, providing a rare opportunity to study pristine solar system material. Its retrograde orbit and brightness evolution were well observed, with a peak magnitude of 6.2 in mid-September 2014. The comet's infrared spectroscopy revealed depletion of most volatile ices except ammonia, and a heterogeneous composition indicated by changing ethane and methanol abundances in early September 2014. Its passage through the inner solar system was tracked by ground-based observers and the STEREO HI-1B instrument. The comet's orbital history—with a period of several million years before entering the planetary region and a future period of about 6000 years—illustrates the gravitational perturbations that affect Oort cloud objects. The observations contributed to understanding the chemical diversity of cometary nuclei and their survival near the Sun.

Did You Know?

• It peaked at magnitude 6.2 in mid-September 2014, but had an elongation of only about 35 degrees from the Sun.
• Infrared spectroscopy showed most volatile ices are depleted except for ammonia.
• Before entering the planetary region, its orbital period was several million years; after leaving, it will be about 6000 years.