doc: update

README.md

@@ -97,7 +97,7 @@ positions are given by:
 
 ```math
 \vec{r_1} = \begin{bmatrix} 0.159321004 \\ 0.579266185 \\ 0.052359607 \end{bmatrix} \text{ [AU]} \quad \quad
-\vec{r_2} = \begin{bmatrix} 0.057594337 \\ 0.605750797 \\ 0.068345246 \end{bmatrix} \text{ [AU] }
+\vec{r_2} = \begin{bmatrix} 0.057594337 \\ 0.605750797 \\ 0.068345246 \end{bmatrix} \text{ [AU]} \quad \quad
 ```
 
 The time of flight is $\Delta t = 0.010794065 \text{[year]}$. The orbit is