https://greatastromatcher.com/Learn/Glyphs
A planetary symbols or glyphs are a graphical symbols used in astrology and astronomy. They we're also used in alchemy to represent the metals associated with the planets and in calendars for their associated days. The earliest forms of these symbols appear in Greek papyrus texts of late antiquity (Astronomical Papyri from Oxyrhynchus). Their current forms first appeared in the Renaissance. It's important to mention that scientific explanation of their meaning is right out ridiculous.
Symbols are made up of three basic components: circle, semicircle (crescent) and cross.
Circle - Spirit
A circle is considered as the simplest and most perfect form. It has no beginning and no end, it is complete and all-encompassing. It is self-sufficient and has the ability of self-preservation. The circle demonstrates a continuing whole. It represents eternity, Divine life-force, everlasting Spirit or the Ultimate Reality. It is also a symbol for vitality, wholeness, completion and perfection.
In ancient Greece it was called λόγος (lógos, "word, speech, reason"). In Hinduism it's known as Brahman, which means or imply the highest universal principle, the ultimate reality in the universe - final cause of all that exists. In ancient China it's Tao or Dao (道, "way, path"), which also signifies a principle - the underlying natural order of the Universe.
Semicircle - Soul
A semicircle is a half of a circle. If full circle represents the Spirit, than half of a circle represent its "not complete" reflection. It has two parts, visible and invisible one. If full circle is the ocean, than semicircle is a droplet of that ocean. So semicircle represents the Soul, the immaterial aspect or essence of a being.
In ancient Greece it was called ψυχή (psukhḗ, "soul, breath"). In Latin it's called psychē ("psyche, soul, spirit"). In Hinduism it's known as Ātman, word that refers to the (universal) Self. It comes from the word Atma, a Sanskrit word which refers to "essence, breath".
Cross - Matter
A cross is a geometrical figure consisting of two, usually perpendicular, intersecting lines or bars. With four lines, going from center, it symbolises 4 elements, also 4 cardinal points in a sine wave. So it represents material, concrete, transient, temporal and imperfect. It represents Matter and physical body.
It also illustrates the place where the sky and the earth meet, so in ancient Egypt, it was considered as a sign of the union of masculine and feminine, a source of all creation, of objective and subjective. It was also used as a symbol of consecration, especially pertaining to burial.
X is in Roman numerals also a symbol for 10, and number 10 represents the beginning of a new cycle or rebirth, a higher level of a spiral, sometimes a higher purpose and inner wisdom, which coincides with the shape and meaning of Phoenician letter Tāw (x) and Hebrew Tav (ת), which represents life and resurrection.
There is also an Arrow, which is actually a defective cross, and because it is out of balance, it represents or indicates direction, the direction of energy towards a specific aim or goal.
