It's
the most similar planet to Earth that has ever been discovered
John Grunsfeld, associate
administrator for Nasa's Science Mission Directorate in Washington, said:
"Today we're announcing the
discovery of an exoplanet
that as far as we can tell is a pretty close cousin of Earth. It's the closest
so far. It's Earth 2.0."
What does he mean by “pretty close?”
Everything about Kepler
452b - from its size, the length of its years, the estimated conditions on the
surface - is very similar to Earth.
Years
on Kepler 452b are about the same duration as they are on Earth
A year on the
newly-discovered planet - the time it takes to orbit its star, Kepler 452 - lasts for 385 days, only 20 days longer than a year
here on Earth. That’s more unique than you think. For example, a year on Venus,
the closest planet to the Earth, lasts only 88 Earth-days. A year on
Neptune, further out in our solar system, is the equivalent of 185 Earth-years.
It's
spent billions of years within the optimal habitable distance of its star
Kepler 452, the planet's
star, is around 1.5 billion years older than our Sun. If a planet is too close to its star, it will be too hot to host life. If it's too far away, it will be too
cold.
However, Kepler 452b has been the
perfect distance from its star for many billions of years. According to Jon
Jenkins, the Kepler data analysis lead at
NASA's Ames Research Centre,
this means it's possible that it hosts life on its surface, or at least could
have at some point in its history.
This brings all sorts of other “life
essential factors” into play.
The planet's star, Kepler 452, is slightly bigger than our own Sun. The added light and heat
energy that the planet receives from the star not only means it is slightly
warmer than Earth, but could also mean that plant life could thrive there,
especially as there’s also a good chance liquid water is present.
Remember, since plant photosynthesis is what produces the air we breathe, that means this essential building block
of life has a good chance of living on Kepler 452b.
Jon Jenkins told the
press conference: "The sunshine from Kepler's star is very similar to
sunshine from our own star, and plants could be able to photosynthesise just
the same."
"It would feel a lot
like home."
You
could even get a tan there
Dr Daniel Brown, an
astronomy expert at Nottingham Trent University, said: "Kepler 452b
receives the same kind of spectrum and intensity of light as we do on Earth.
This means plants from our planet could grow there if it were rocky and had an
atmosphere. You could even get a healthy
tan like here on holiday."
But don’t get too excited just yet
Unfortunately,
it's pretty much impossible to get there (at the moment)
Yes, Kepler 452b is warm,
possibly wet, and might be able to host plant life - BUT, it's 1,400 lightyears
away.
(A lightyear is the distance that a beam of light can travel in a
year. Light travels at over 670 million miles
per hour. Light from the Sun takes around eight minutes to reach Earth, so
naturally, a trip to Kepler 452b would take an incredibly long time.)
Let’s put that into
perspective with something else that was currently in the news:
Nasa's New Horizon probe - the one that
recently took the amazing pictures of Pluto - left Earth's orbit faster than any other spacecraft
before it, at around 36,373 mph.
If a specially adapted New
Horizon launched at this speed towards Kepler 452b, it would take YOU around
25.8 million years to get there. What does that mean? Well, think about it this
way...early, primitive humans only developed around 2.5 million years ago. So
by the time you get there, you’d probably have evolved into something very
special?
Sad news? Perhaps. But think about it in another way. If scientists are finding planets like this, it increases the probability of them uncovering evidence of what many have suspected for years.
We are not alone...
(Just as well X Files is coming back. Mulder and Scully might get very busy, real soon)
Source material: NASA Independent Newspaper UK
