Why Earth 2.0 could be just like Earth

By Nicholas RotherhamNewsbeat reporter   24/07/15

"Oh this is incredibly exciting," said one of the many scientists put in front of the TV cameras.

But whether or not you own a telescope or have a star named after you, this really is exciting.

Nasa scientists say they have discovered a planet more like Earth than any other.

Here's our guide to why you (as well as those scientists) should be excited and why "Earth 2.0" is just like our home planet.

Firstly... that name

Nasa's labelled the new discovery "Earth 2.0" after describing it as our planet's "bigger cousin".

Kepler-452b is its more technical name. It was named after the telescope that spotted[1] it, the Kepler space telescope.

Is it really like our Earth?

Image caption

Well, yes according to Dr Suzanne Aigrain, from the University of Oxford.

"I do believe the properties described for Kepler-452b are the most Earth-like I've come across for a confirmed planet to date," she said.

"We've finally found a planet that's incredibly close to what it's like here," added doctor of space physics, Martin Archer.

"We know it's about 60% bigger than the planet Earth."

Kepler-452b has a sun...

Image captio

Kind of. It orbits[2] at a very similar distance from its star to Earth.

That star belongs to the same class as the Sun.

While similar in size and brightness, Kepler-452b's host star is 1.5 billion years older than ours.

Scientists reckon[3] that could mean a possible future for the Earth.

How long does it take to orbit that star?

It's not 365 days if that's what you're thinking.

But it is close. 385 days. So its orbital period is just 5% longer than Earth's.

It's made out of the same stuff...

Scientists believe so, but they have yet to check it out properly. It is more than 1,000 light years away after all.

If it is rocky, the world would likely still have active volcanoes and its gravity would be roughly twice that on our own planet.

"It would be about five times more massive so you would feel a lot heavier there," added Dr Archer.

Hang on, does that mean it could have life on it?

Nasa believes Kepler-452b has had "considerable time and opportunity for life to exist".

One of the agency's analysts said: "For plants the sunshine from this star is very similar to the sunshine from our star, so the plants would photosynthesize[4] just like on Earth."

Maybe ET does exist after all then. He might not be wrapped in a white blanket mind.

資料來源: BBC News http://www.bbc.co.uk/newsbeat/article/33646188/why-earth-20-could-be-just-like-earth

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Structure of the Lead：   
WHO-Earth 2.0   
WHEN-not mentioned   
WHAT-Why Earth 2.0 could be just like Earth   
WHY- 1.they orbits similar distance. 2.maybe made out of the same stuff    WHERE- 1,000 light years away from Earth
HOW-not mentioned

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[1] spot (v.) 發現
[2] orbit (v.) 繞軌道運行
[3] reckon (v.) 猜想;估計
[4] photosynthesize (v.) 進行光合作用