(PUC - RS - 2017/2)Thrilling Discovery of Seven Ea

(PUC - RS - 2017/2)

Thrilling Discovery of Seven Earth-sized Planets Orbiting Nearby Star

Ian Sample Science editor-published on Wed. 22 Feb 2017

01  A huddle of seven worlds, all close in size to Earth,
02  and perhaps warm enough for water and the life it can
03  sustain, has been spotted around a small, faint star in
04  the constellation of Aquarius. The discovery, which has
05  thrilled astronomers, has raised hopes that the hunt for
06  alien life could start much sooner than previously thought.
07  The next generation of telescopes are due to switch on in
08  the next decade. Astronomers reported what looked like
09  three planets in orbit around Trappist-1, a star they named
10  after the Trappist robotic telescope in the Chilean desert
11  that first caught sight of the alien worlds. The telescope
12  did not see the planets directly, but recorded the shadows
13  they cast as they crossed the face of the star.

14  It is the first time that so many Earth-sized planets have
15  been found in orbit around the same star, an unexpected
16  haul that suggests the Milky Way may be teeming with
17  worlds that, in size and firmness underfoot at least,
18  resemble our own rocky home. Researchers hope to
19  know if there is life on the planets within a decade. Ignas
20  Snellen, an astrophysicist at the Leiden Observatory in the
21  Netherlands, who was not involved in the study, said the
22   findings show that Earth-like planets must be extremely
23  common. “This is really something new,” he said. “When
24  they started this search several years ago, I really thought
25  it was a waste of time.__________________________.”

26  Astronomers are now focusing on whether the planets
27  have atmospheres. If they do, they could reveal the first
28  hints of life on the surfaces below. The Hubble telescope
29  could detect methane and water in the alien air, but both
30  can be produced without life. David Charbonneau, a
31  professor of astronomy at Harvard University who was
32  also not involved in the latest study, said a growing
33  number of astronomers were getting excited about what
34  he called “the M-dwarf opportunity” – the study of planets
35  around such faint dwarf stars. “It’s a fast track approach
36  to looking for life beyond the solar system,” he said.

Adapted from https://www.theguardian.com/science/2017/feb/22/thrilling-discovery-of-seven-earth-sized-planets-discovered-orbiting-trappist-1-star

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