Page 28 - ARUBA TODAY

A28 SCIENCE
Friday 13 September 2019
Water, temperature right for life at another star’s planet

By MARCIA DUNN
AP Aerospace Writer
CAPE CANAVERAL, Fla.
(AP) — In a tantalizing first,
scientists have discovered
water at a planet outside
our solar system that has
temperatures suitable for
life.
Two research groups an-
nounced this week that
they’ve found water va-
por in the atmosphere of a
planet 110 light-years away
in the constellation Leo. This
so-called Super Earth is just
the right distance from its
star to conceivably harbor
life.
It’s the only exoplanet
known so far to have both
water and temperatures
needed for life, the Universi-
ty College London team re-
ported in the journal Nature
Astronomy on Wednesday.
But lead author Angelos
Tsiaras stressed, “This is defi-
nitely not a second Earth.”
Its star and atmosphere
are so different than ours,
“Earth-like conditions are
not possible,” Tsiaras told
reporters. “The only ques- This artist’s rendering provided by University College London Centre for Space Exochemistry Data researchers shows Exoplanet K2-
tion that we’re trying to ask 18b, foreground, its host star and an accompanying planet in this system.
here, and we’re pushing Associated Press
forward, is the question of one knows if water’s flow- tions are needed to deter- mospheres of hot gas gi- team’s Ingo Waldmann. A
habitability.” ing on the surface. Its star, mine whether the planet is ants circling other stars, the sister planet, meanwhile,
A Canadian-led team an- a red dwarf, is considerably indeed a true water world, latest findings represent the orbits closer to the star and
nounced similar findings smaller and cooler than our using next-generation ob- first detection of water va- is likely too hot to be in the
Tuesday. In a paper just sun, a yellow dwarf, and its servatories like NASA’s por in the atmosphere of habitable zone.
submitted to the Astronom- atmosphere is also different James Webb Space Tele- another type of exoplanet, The cloud cover isn’t too
ical Journal for publication, than ours. scope and the European Tsiaras said. thick on K2-18b, otherwise
these scientists suggest Nonetheless, Tsiaras said Space Agency’s Ariel, both A NASA tally currently lists it would have obscured the
it might even be raining K2-18b could help deter- due to launch in the 2020s. more than 4,000 confirmed water vapor in the atmo-
there. mine, “Is the Earth unique?” Future telescopes on Earth exoplanets and another sphere, according to the
“This represents the biggest The results are doubly ex- and in space should help 4,000 potential candidates. scientists.
step yet taken toward our citing, Tsiaras noted, given uncover more Super Earths Most have been detected The surface, meanwhile,
ultimate goal of finding life this is not only the first Super orbiting red dwarf stars — using the transit method, could be wet or dry. The
on other planets, of proving Earth with water detected believed to be the most where telescopes watch London data suggest water
that we are not alone,” the in its atmosphere but the common planets and stars for a slight, fleeting dim- vapor makes up anywhere
study’s lead astronomer, planet also resides within in our Milky Way galaxy. ming of a star’s light as a between 0.01% and 50% of
Bjorn Benneke of the Uni- the habitable zone of its Super Earths are defined planet passes in the field of the atmosphere — “quite a
versity of Montreal, said in star. as having a mass greater view. big range,” Waldmann ac-
a statement. The research teams used than Earth but less than gas For now, scientists know K2- knowledged. Either way,
Discovered in 2015, the archived data from the giants like Uranus and Nep- 18b takes 33 days to orbit given the planet’s mass, it
planet known as K2-18b is Hubble Space Telescope tune; more than 1,260 have its star, so one year there is would be difficult to walk
twice the size of Earth with and other spacecraft to been confirmed to date. one month here. At this dis- on the surface.
eight times the mass. While analyze the planet’s atmo- While water already has tance, temperatures range “Maybe not quite your va-
it’s thought to be rocky, no sphere. Further observa- been identified in the at- from minus-100 degrees cation destination just yet,”
to 116 degrees Fahrenheit Waldmann joked.q
(minus 73 degrees to 47 de-
grees Celsius.)
The star, glowing red in the
day sky, is believed to bom-
bard the planet with radia-
tion harsh enough to quick-
ly inflict any human visitors
with cancer, although “life
there may have evolved
differently” in order to sur-
vive, noted the London