The week of April 26 – May 2 takes us from Full Moon to Lunar Day 21. This week we will highlight the crater Julius Caesar, viewable early Sunday morning on Day 21.

Julius Caesar on the moonJulius Caesar1: [NE/J11] In the Sea of Tranquillity, locate the partially ruined crater Julius Caesar near the western shore of Tranquillitatis. The floor of this crater is unusual in that it gradually darkens as you go north until it becomes one of the darkest areas on the surface of the Moon. The lighter-hued portion of the floor (and of the surrounding area) is believed to be composed of material that was blasted out of the Imbrium basin 3.9 billion years ago. Search this region to look for features that are radial to Mare Imbrium. They are further evidence of sculpting that resulted from the creation of the Imbrium basin.

1 Caesar, Julius: (100 BCE – 44 BCE) Roman general and statesman who, because of his conquests, amassed an enormous amount of power. When he was ordered by the Senate to stand trial for various charges, he marched on Rome with his armies and emerged as the undisputed leader of the Roman world. Contrary to popular opinion, Julius Caesar was not the emperor of Rome but the “Dictator in Perpetuity” who transformed Rome from a Republic to an Empire. It was his heir, Augustus, who was the first emperor. Julius was assassinated on March 15, 44 BCE, by a group of senators who wished to restore the constitutional Republic.


It is highly recommended that you get a copy of Sky and Telescope’s Field Map of the Moon, the very finest Moon map available for use at the telescope. It is available for $10.95 at and on Amazon. All features mentioned in this blog will be keyed to the grid on the Field Map and will look like this: Plato: [NW/D9]

Courtesy of Gray Photography of Corpus Christi, Texas
Lunar photos: NASA / USGS / BMDO / LROC / ASU / DLR / LOLA / Moon Globe. Used by permission

Andrew Planck
Julius Caesar on the Moon

Leave a Reply

Your email address will not be published. Required fields are marked *