0:00:11 > 0:00:12Good morning, guys!
0:00:12 > 0:00:14Jenny here with your first Newsround this Monday.
0:00:14 > 0:00:16First, to the experiment with two twin brothers that's
0:00:16 > 0:00:17completely out of this world.
0:00:17 > 0:00:20Watch this.
0:00:20 > 0:00:21This is Scott Kelly.
0:00:21 > 0:00:24He's a NASA astronaut and this is his identical twin brother,
0:00:24 > 0:00:28Mark, who also used to be a NASA astronaut.
0:00:28 > 0:00:32Scott went up to space and lived there for 340 days
0:00:32 > 0:00:34and Mark stayed on Earth.
0:00:34 > 0:00:37Scott returned to Earth one year ago.
0:00:37 > 0:00:39NASA is studying them to find out how being in space affected
0:00:39 > 0:00:43Scott's body and compare it to Mark's on Earth.
0:00:43 > 0:00:46This is what they have found out so far.
0:00:46 > 0:00:48Scott grew around two inches in space.
0:00:48 > 0:00:52His spine expanded because he didn't have the pull of Earth's
0:00:52 > 0:00:55gravity on his body, but he went back to his
0:00:55 > 0:00:57normal height soon after returning to Earth.
0:00:57 > 0:01:01The twins have almost identical DNA and this decides
0:01:01 > 0:01:03things like how they look.
0:01:03 > 0:01:06The DNA is stored in something called a chromosome,
0:01:06 > 0:01:07which looks like this.
0:01:07 > 0:01:10Whilst Scott was in space, his chromosomes got longer
0:01:10 > 0:01:13when you would expect them to get shorter, like his twin
0:01:13 > 0:01:15Mark's on Earth.
0:01:15 > 0:01:17Scientists are trying to work out what this means.
0:01:17 > 0:01:20When Scott came back to Earth they found that his brain
0:01:20 > 0:01:22was slightly slower than Mark's.
0:01:22 > 0:01:25After a year in space he was taking a bit longer to respond
0:01:25 > 0:01:27and solve problems in tests.
0:01:27 > 0:01:30NASA wants to use the twins' information to help figure out how
0:01:30 > 0:01:33to keep astronauts healthy if they ever send them
0:01:33 > 0:01:38to Mars in the future.
0:01:38 > 0:01:42OK, time for a quick round-up of some of the top sport stories:
0:01:42 > 0:01:45It was a very good weekend for TeamGB at the European
0:01:45 > 0:01:46Indoor Athletics.
0:01:46 > 0:01:48They won seven medals on the final day.
0:01:48 > 0:01:54Laura Muir became only the second Briton to win two individual events
0:01:54 > 0:01:59at the games after adding gold in the 3,000 metres to the 1,500
0:01:59 > 0:02:02metres title she took on Saturday.
0:02:02 > 0:02:05To footie now and Spurs are seven points behind Chelsea at the top
0:02:05 > 0:02:07of the Premier League after beating Everton 3-2.
0:02:07 > 0:02:10It's their ninth home win in the league on the trot -
0:02:10 > 0:02:11a new club record.
0:02:11 > 0:02:15Harry Kane scored two and there was also a goal
0:02:15 > 0:02:19from his England team mate Delle Ali.
0:02:19 > 0:02:22Manchester City are one point behind Spurs after winning 2-0 at bottom
0:02:22 > 0:02:24of the table Sunderland.
0:02:24 > 0:02:27Sergio Aguero scored his 23rd goal of the season
0:02:27 > 0:02:29and Leroy Sane added a second.
0:02:29 > 0:02:37It's a fourth league win in a row for Pep Guardiola's side.
0:02:37 > 0:02:39Some music lovers out there may have dreamed
0:02:39 > 0:02:42of being on a TV talent show, but when Tom got a call
0:02:42 > 0:02:46from Britain's Got Talent he decided to turn them down.
0:02:46 > 0:02:49I went to find out why.
0:02:49 > 0:02:51"Dear Simon and Britain's Got Talent, thanks for all your phone
0:02:51 > 0:02:54calls and invitations to your TV talent show.
0:02:54 > 0:02:56Sorry if my first answer wasn't clear enough,
0:02:56 > 0:02:58but I don't want to be in this competition.
0:02:58 > 0:03:01I sing songs and write songs for other reasons I can't
0:03:01 > 0:03:03even put into words.
0:03:03 > 0:03:06No need to phone me back as now everyone has seen this
0:03:06 > 0:03:08so I could never come on your show without looking daft.
0:03:08 > 0:03:12Yours sincerely, Tom".
0:03:12 > 0:03:15When I was six-years-old I started getting music lessons.
0:03:15 > 0:03:16Who inspires you?
0:03:16 > 0:03:18I listen to quite a lot of James Bay.
0:03:18 > 0:03:21He's just a really nice person and it's nice to see that people
0:03:21 > 0:03:24in the music industry are nice people.
0:03:24 > 0:03:26What do you think is brilliant about performing?
0:03:26 > 0:03:27The reaction from the crowd.
0:03:27 > 0:03:30When you get a good reaction from the crowd, it makes you feel
0:03:30 > 0:03:31you can be yourself.
0:03:31 > 0:03:34What do your friends think about the fact that you do this?
0:03:34 > 0:03:36They don't really care, in fairness.
0:03:36 > 0:03:39Whenever I'm trying to tell them about it, they will tell us to be
0:03:39 > 0:03:42quiet because they think I'm being a bit big headed.
0:03:42 > 0:03:45How did Britain's Got Talent get in touch and what did they say?
0:03:45 > 0:03:47They rang us asking if I could do their show
0:03:47 > 0:03:50and my first answer was no, then they rang us again
0:03:50 > 0:03:51and we also said no that time.
0:03:51 > 0:03:54Then the third time when they rang us we said no again.
0:03:54 > 0:03:58I just feel that it wasn't a show that I wanted to do.
0:03:58 > 0:04:00I didn't really want to take part in a music talent show
0:04:00 > 0:04:03and I like what I'm doing at the moment.
0:04:03 > 0:04:03I'm enjoying myself.
0:04:03 > 0:04:06And why did you decide to write the letter?
0:04:06 > 0:04:09We were getting a bit irritated by the fact they kept on ringing us
0:04:09 > 0:04:12and it was just a nice way of letting them know that we didn't
0:04:12 > 0:04:14want to be on the TV talent show.
0:04:14 > 0:04:17What do you think of TV talent shows?
0:04:17 > 0:04:20I don't think there is anything wrong with them, I just thought
0:04:20 > 0:04:22that it wasn't really something that I wanted do.
0:04:22 > 0:04:25I think it is important for me to do things my way
0:04:25 > 0:04:28so I can feel like myself.
0:04:28 > 0:04:30What are your hopes for the future?
0:04:30 > 0:04:34Well, I'm just going to take it as it comes, to be honest.
0:04:34 > 0:04:36I would love to, obviously, have music as my career,
0:04:36 > 0:04:41but I'm just going to play the gigs that come and see how it goes.
0:04:41 > 0:04:43That's all from me.
0:04:43 > 0:04:46Newsround is back at 8.15am.
0:04:46 > 0:04:50Head online for loads more great stories including the top tooters
0:04:50 > 0:04:53of the conch shell blowing competition in Florida!