Markdown gives you many options with formatting based on textual syntax. However, one of the items missing is the use of Centering. This is usually because centering is done based on the display engine (i.e. cascading style sheets) and not the actual text formatting.
However, there is a workaround thanks to Jon Garrison. This is using an invisible image to be inserted into the text, pushing your text to be more centered.
Using these Base64 blank images (1-pixel, 25-pixel, and 100-pixel widths respectively), inserts a single invisible
image. You then continue to paste this image code to push your text until you get it where you want it.
Depending on the resolution and/or size of the client’s browser, what looks centered to you, may not be
centered on their screen, as text boxes will automatically expand or contract.
If this is a header-size text, make sure to add the header size (i.e. ##) before the image.