Karmandir 
About
The Surya Yantra is the number yantra of Surya dev, who sits at the centre of the nine grahas. It is the simplest magic square of all: the numbers 1 to 9, each used once, placed so that every row, every column and both diagonals add up to 15, with 5 in the middle. An old jyotish text, the Garga Samhita (not the Krishna book of the same name), already links this square with the worship of the nine grahas, and the squares of the other eight grahas are made from it by adding 1 to 8 to every number. Families keep it in the puja place and remember Surya dev on Sundays with his verse from the Navagraha Stotram.
Parts of the yantra
Number square: nine cells, written in Devanagari digits in the drawing — top row 6, 1, 8; middle row 7, 5, 3; bottom row 2, 9, 4. Every row, column and diagonal totals 15, and 5 sits in the middle cell. Any two numbers facing each other across the middle always add up to 10. Lines: a gold outer line closes the square and saffron lines divide it into nine cells. Frame: a plain border of three lines around the square, marking the yantra's space.
How to use it
Place the yantra upright on a clean cloth in the puja place. On a Sunday, or on any day, light a diya, offer a flower and sit quietly facing it. Rest your eyes first on the middle number, 5, then move them through the numbers from 1 up to 9, one cell at a time; this gives the mind one calm thing to follow. Then read Surya dev's verse from the Navagraha Stotram (जपाकुसुमसङ्काशं…) once, or 11 times. Wipe the yantra with a soft, dry cloth to keep it clean.
जपाकुसुमसङ्काशं काश्यपेयं महाद्युतिम्। तमोऽरिं सर्वपापघ्नं प्रणतोऽस्मि दिवाकरम्॥
Japakusuma Sankasham Kashyapeyam Mahadyutim →
Frames differ from print to print: the NCERT figure, for example, draws this square inside a sun disc with rays. Many prints use the digits 1, 2, 3 instead of the Devanagari digits used here. The numbers and their places stay the same.
