Comet Kohoutek was discovered by Lubos Kohoutek in March 1973 while viewing asteroid images at the Hamburg Observatory. The tail of a comet generally points away from the sun. During a portion of Comet Kohoutek's journey, it developed an antitail pointing toward the sun. Calculations predicted Comet Kohoutek would reach perihelion at the end of 1973. These predictions were fairly accurate. Comet Kohoutek achieved its closest pass by the sun on December 28, 1973.
Comet Kohoutek's passage by Earth coincidentally occurred at the same time as a Skylab mission, making it one of the most observed comets in history. It was sighted in 1973 with enough advance warning that NASA initiated Operation Kohoutek to observe the comet from Earth and from space. Comet Kohoutek was a new comet that had never been observed. The best view from Earth was on January 15, 1974, when a side view of the comet could be seen.
Comets are composed of frozen materials such as water, carbon dioxide, ammonia and methane with a mixture of dust. These materials originate from the time the Solar System was formed. The icy nucleus is surrounded by a large cloud of dust and gas that forms as the sun vaporizes the ice. Some comets develop two tails as they travel closer to the sun.