article_snippet.sent: This so-called ‘Snowball Earth’ theory suggests that the whole planet was once entirely frozen over - and the whole planet could have implications for finding life on other frozen worlds like Europa and Enceladus.
article_snippet.sent: The reasons why the whole planet was frozen are not understood.
article_snippet.sent: It suggests that the entire Earth was subjected to a ‘deep freeze’, with the oceans turning into ice 1,000ft (300 metres) thick.
article_snippet.sent: We had times where We really had a completely frozen Earth,’ Dr Herwartz told Discovery News.
article_snippet.sent: The exact causes for why Earth Earth seemingly froze over are not clear, though.
article_snippet.sent: And Dr Herwatz said a drop in CO2 levels was likely the cause of Earth turning into a snowball. '
article_snippet.sent: It suggests that Earth Earth was subjected to a ‘deep freeze’, with the oceans turning into ice 1,000ft (300 metres) thick (stock image shown)
article_snippet.sent: In fact, Dr Herwatz said the amount of melting probably caused Earth to go through a ‘supergreenhouse period’.
article_snippet.sent: The ‘Snowball Earth’ theory is not set in stone, though - some have instead suggested The ‘Snowball Earth’ theory may have been more of a slushball.
highlights_snippet.sent: The reasons why the whole planet was frozen are not understood .
  