The balloon hit a tree and burst.

气球碰到树上就爆了。

《牛津词典》

The balloon burst with a bang.

气球啪的一声爆炸了。

《新英汉大辞典》

If there wasn't a delay, then the image would be taken before any of the balloon has really burst at all.

如果没有这个延时的话，那这个图片就只能拍到气球真正爆炸之前的画面了。

youdao

Finally, at a height of almost 19km, the balloon burst and the payload fell back to earth helped along by a parachute.

BBC: Giant weather balloon carries out its sky mission