hello, so I have run into a little bit of trouble. I was creating newtons cannon in excel and it dose not work as supposed to. What happens is a very powerful slingshot effect. It will stay on orbit for a while, but eventually it will fly away.

my code looks like that. maa - earth ; kuul-bullet ; v-velocity

Because it is still in a test phase, I have left out some constants that do not change the orbits shape.

//setting centre

x0 = maa.Left + maa.Width / 2

y0 = maa.Top + maa.Height / 2

//mass

m = Sheets("nwkahur").Range("a2").Value

// input speed

vx = Sheets("nwkahur").Range("A1").Value

vy = 0

//movement

Do

x = x0 - kuul.Left + kuul.Width / 2

y = y0 - kuul.Top + kuul.Height / 2

r = (x ^ 2 + y ^ 2) ^ (1 / 2)

//new position

kuul.Left = kuul.Left + vx

kuul.Top = kuul.Top + vy

//new velocity

vx = vx + m / (r ^ 3) * x

vy = vy + m / (r ^ 3) * y

pause 0.0001

loop

I can understand that the problem is in calculations but, I cant but my finger on it. I would be very grateful, if you could help.

Kristjan Vilgo

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I wrote a similar code as urs and i think i am just as you stuck at the middle :)