**why is it that this code failed to run when i used different variable name from the function declared name**

```
function orbitalPeriod(arr) {
// giving vaues of the earth setted to constant
const GM = 398600.4418;
const earthRadius = 6367.4447;
// reading through the arr using map method to return with function with parameter of name and avgAlt
return arr.map(({name, avgAlt}) => {
// adding together the radius of the earth with the average altitude
const earth = earthRadius + avgAlt;
// create rouded orbital Period, which will be used to replace the position of avgAlt in question
const orbitalPrd = Math.round(2 * Math.PI * Math.sqrt(Math.pow(earth, 3) / GM));
return {name, orbitalPrd};
});
}
orbitalPeriod([{name : "sputnik", avgAlt : 35873.5553}]);
```

```
**but this one worked out very well** :point_down: :point_down:
```

```
function orbitalPeriod(arr) {
// giving vaues of the earth setted to constant
const GM = 398600.4418;
const earthRadius = 6367.4447;
// reading through the arr using map method to return with function with parameter of name and avgAlt
return arr.map(({name, avgAlt}) => {
// adding together the radius of the earth with the average altitude
const earth = earthRadius + avgAlt;
// create rouded orbital Period, which will be used to replace the position of avgAlt in question
const orbitalPeriod = Math.round(2 * Math.PI * Math.sqrt(Math.pow(earth, 3) / GM));
return {name, orbitalPeriod};
});
}
orbitalPeriod([{name : "sputnik", avgAlt : 35873.5553}]);
```

**so i want to know why it didnt worked out as i expected it to do. concerning the orbitalPrd that didnt work, and orbitalPeriod that worked**

*thank you*