:00:00. > :00:00.Novak Djokovic has become the first player to win four
:00:07. > :00:13.He beat Roger Federer in the final in London.
:00:14. > :00:19.Djokovic knew he had to play at his best against Federer,
:00:20. > :00:21.who defeated him earlier in the week at the group stages.
:00:22. > :00:24.The champion seems to be pretty proud of the win.
:00:25. > :00:25.I'm just trying to enjoy every moment,
:00:26. > :00:28.you know, on the court, and cherish every moment that I
:00:29. > :00:34.You know, when you are a kid growing up, dreaming to play
:00:35. > :00:37.tennis, it's your dream to be into a tournament like this and to fight
:00:38. > :00:39.for the biggest trophies in the sport.
:00:40. > :00:44.So thank you all very much for making this day special.
:00:45. > :00:47.Some wildlife news now and a northern white rhino, one of only
:00:48. > :00:50.four believed to be left in the world, has died at a zoo in
:00:51. > :01:01.Nola, a 41-year-old female had been living at San Diego Zoo Safari Park
:01:02. > :01:04.She had to be put down after becoming ill.
:01:05. > :01:06.Just three remaining northern white rhinos live at a highly
:01:07. > :01:10.Rhinos are under threat in the wild because people hunt them
:01:11. > :01:14.Next to the dramatic rescue of Mufasa the lion believed to be the
:01:15. > :01:16.last wild animal in a South American circus.
:01:17. > :01:19.It's thought Mufasa had been captured from the wild as a cub and
:01:20. > :01:23.the circus kept him chained to the back of a truck his whole life.
:01:24. > :01:29.After being rescued and brought back to health the 22-year-old big
:01:30. > :01:33.cat was taken on a three day journey, by road and boat, to a
:01:34. > :01:36.special reserve in the Amazon rainforest where he can now live the
:01:37. > :01:40.Thousands of starling birds flying together to create mesmerising
:01:41. > :01:44.It's thought it could be a form of protection from predators, or a way
:01:45. > :01:52.And now it's been discovered flocks continue swarming
:01:53. > :01:57.A new study has found they can fly around for more than an hour, with
:01:58. > :01:59.researchers also surprised at just how many mumurations there are.
:02:00. > :02:02.It's murmaration season right now so head online to the Newsround website
:02:03. > :02:05.and find out more about how you can spot them.
:02:06. > :02:07.Now to a high-tech solar powered plant that
:02:08. > :02:11.It's in Morroco in North Africa and uses melting salt to create energy.
:02:12. > :02:17.Wasassat, an ancient city in East Morocco is
:02:18. > :02:26.Row upon row of mirrors capturing the power of the desert sun.
:02:27. > :02:31.Once complete, it will be able to provide energy to a million people.
:02:32. > :02:37.During daylight hours, these mirrors track the sun through the sky.
:02:38. > :02:42.It is known as concentrated solar power.
:02:43. > :02:45.Each mirror directs the sun's rays that hit the tube
:02:46. > :02:52.Outside the tube is oil which is boiled to 400 Celsius,
:02:53. > :02:57.then transported and used here to make steam and produce electricity.
:02:58. > :03:00.But in order to generate power after dark,
:03:01. > :03:03.it uses the sun's energy to melt salt in this huge cylinder which has
:03:04. > :03:13.This thing you see here is a tank where we store salt just like the
:03:14. > :03:18.During the day, we heat this up, in order to keep the heat we will
:03:19. > :03:22.use to produce electricity, and this is quite a big innovation.
:03:23. > :03:26.We are able to store up to three hours of energy.
:03:27. > :03:28.It's hoped that this sort of technology is the future of
:03:29. > :03:31.renewable energy and poorer nations want help from rich countries to
:03:32. > :03:47.develop technology like this to help fuel the future, day and night.
:03:48. > :03:49.I'm pretty sure singing your national anthem in front
:03:50. > :03:51.of thousands is something no one would forget.
:03:52. > :03:53.Well, this 7-year-old boy from Australia stole the show
:03:54. > :04:02.Ethan here stepped up to sing the national anthem before
:04:03. > :04:27.And then still managed to finish the song after a -- his pick-ups
:04:28. > :04:29.interrupted the song. Ethan still managed to finish the
:04:30. > :04:32.song and got a massive round of