<prompt> unaweza kugeuza matini haya ya swahilikwa kiingereza?wanaastronomia wengi wanaamini kuwa ulimwengu ulianza na milipuko mkubwa uitwao big bang miaka bilioni 13.7 iliyopita.  <response>: most scientists believe that the universe was created by a big bang about: 13 billion years ago. 