Download Seven `beautiful` Earth-sized planets found

FRIDAY, 24 FEBRUARY 2017
THEDAY.CO.UK
Seven ‘beautiful’ Earth-sized planets found
NASA has discovered a solar
system 39 light years away with
a record seven exoplanets. It is
more evidence that the universe
is teeming with Earth-like
worlds. How should it make us
feel?
Welcome home? NASA says three of the seven new planets are in the star’s “Goldilocks zone”.
Have you ever looked up at the night sky and
wondered whether, somewhere out there in the
blackness of space, a planet not unlike Earth
revolves around a foreign sun?
Scientists now know that the answer is a
resounding yes — and on Wednesday NASA
made an astonishing announcement: it had
found not one, but seven potentially Earth-like
planets at once.
They are all orbiting a small, faint star called
Trappist-1, around 39 light years away. Each
planet is a similar size to Earth, and they are
close enough to the cool sun to be the perfect
temperature for liquid water — and maybe
even life.
“This is really something new,” said the
astrophysicist Ignas Snellen.
The findings confirm the idea that Earth-like
planets are extremely common. In fact, back in
2013, NASA predicted that there could be at
least 17 billion Earth-like planets in the Milky
Way alone — possibly as many as 50 billion.
The vast majority of those are not inhabited,
Q&A
of course — or even habitable. Only some will
be in the “Goldilocks zone” of a star’s orbit,
while many will have unfriendly atmospheres
thick with hydrogen and helium. And it is
unclear how many of the planets might
harbour the water molecules which are so vital
to life as we understand it. So none of this is
proof of alien life — though those who dream of
other worlds will be hugely excited by the news.
Nevertheless, this latest discovery is
momentous in itself. Scientists are now
focusing on discovering whether any of the
new planets have atmospheres. The James
Webb Telescope, which will replace the Hubble
telescope next year, will give a much clearer
picture of the distant solar system.
The idea that these planets are just seven
of a potential 50 billion — in our galaxy alone —
is staggering. When Earth was first
photographed from outer space in images like
Earthrise and The Blue Marble, its fragile,
isolated beauty changed the way people
thought about our planet. It was, said one
photographer, “the beginning of the
environmental movement”.
Could thinking about billions of other worlds
have an equally mind-altering effect?
within the next decade, rather than on a much
longer timescale. The next stage is to study
which of these planets has conditions most
likely to support life.
disagree wildly. One expert recently estimated
that our galaxy contains tens of thousands of
‘civilisations’. But academics at Princeton
University recently stated confidently that Earth
was probably the only cradle of life in the entire
universe.
Q: Still no aliens, then?
A: Not yet, sorry. But it is a major step in the
hunt for extraterrestrial life: scientists say that Q: So what are my odds of meeting ET
these seven planets could help them start the someday?
search for alien life sooner than they thought — A: That’s a question on which scientists
Just a speck
To some, the vast array of other planets makes
life here on Earth seem totally insignificant.
When we are just a speck on the edge of
infinity, they ask, why worry about bills or
deadlines or social expectations? Discoveries
like these teach us that we might as well do as
we please — the universe does not care.
For others, the vastness and dignity of
space sparks exactly the opposite revelation:
being part of something so unfathomably
enormous is humbling. The fact that our lives
are played out on the corner of such an
awesome stage gives our actions greater
significance, they say, not less.
YOU DECIDE
ACTIVITIES
SOME PEOPLE SAY...
1. How does it make you feel to know that our
galaxy contains billions of other Earths?
1. Create a piece of art, music or writing with
the title ‘17 billion worlds’.
“For small creatures such as we the vastness
is bearable only through love.”
2. Would it still be worth exploring the universe
if we knew that we could never find life outside
Earth?
2. Research the particular features of planet
Earth that make it suitable for the
development of life, and present this
information in a poster.
WHAT DO YOU THINK?
discovered that 17% of its stars had Earth-like
planets in close orbit. The Milky Way contains
around 100 billion stars, suggesting that there
are at least 17 billion such planets in our
galaxy. If you include harder-to-detect planets
further out in orbit, the number rises to 50
billion.
main requirement is that it is neither too hot
nor too cold. Just like the fairytale, in other
words, the temperature must be “just right”.
WORD WATCH
Earth-like planets – To qualify as “Earth-like”,
a planet does not have to have water, let alone
rainforests, pizzas and Justin Bieber. The
phrase simply describes any dense, small-to
medium sized planet with a rocky surface.
50 billion – After scanning a distant
constellation, in 2013 a team of astronomers
BECOME AN EXPERT
Notes
Goldilocks zone – In the orbit of each star lies
a “habitable zone”, in which planets could
theoretically be found that support life. The
Earthrise – This photo of the Earth hovering
just over the moon’s surface was taken on the
Apollo 8 flight, the first manned mission to
orbit the moon. It has been called the most
influential photo of all time.
Read this article on theday.co.uk for links to recommended videos and further reading.