Chaikovskij is a crater on Mercury. It has a diameter of 165 kilometers. Chaikovskij is named for the Russian composer Pyotr Ilyich Tchaikovsky, who lived from 1840 to 1893. (wikipedia entry)
A crater is a circular depression likely created by an impact event. On Mercury they are named after deceased artists, musicians, painters, and authors who have made outstanding or fundamental contributions to their field and have been recognized as art historically significant figures for more than 50 years.
Image Source. Marker locations are approximate and may not always appear to align with image on map.