GHOSTLY PLANET GOES BOO
astronomers claimed the discovery of an exoplanet in the habitable zone
of a nearby star, declaring: “…the chances of life on this planet are
Two weeks later, other astronomers, through more careful analysis, showed this and other promising planets are just ghostly apparitions.
Gliese 581 is a mundane red dwarf star, remarkable only for being home to the most non-existent “habitable” planets.
20 light-years away (120 trillion miles), and less than a third of our
Sun’s size and mass, Gliese radiates only 1/80th as much energy as our
Sun. Most of its light is infrared, invisible to human eyes. It also
radiates body-piercing x-rays.
581b was the first planet discovered orbiting this star. (The naming
convention is: suffix “a” denotes the star; its planets are named “b”,
“c”, “d”,… in the order of discovery.) Gliese 581b is the size of Uranus
in our Solar System, but is so close to its star that its year lasts
only 5 Earth-days, making it an ghoulish inferno.
came “c”, the first Gliese planet that was declared “habitable.” Gliese
581c is at least 5.5 times Earth’s mass, and orbits its star in 13
Earth-days. Astronomers initially said its surface temperature was balmy
20ºC (68ºF). Later analysis using planet climate models raised that
estimate to 500ºC (932ºF), hot enough to boil anyone’s cauldron.
came “d”, said to orbit in 83 days, which was later revised to 67 days.
The closer orbit gave “d” 30% of the light energy that Earth receives
(by comparison, life-less Mars gets 40% of Earth’s light intensity).
Some claimed “d” could be habitable if it had a dense atmosphere. Recent
analysis concluded that planet “d” does not exist !
581e is a real planet, with twice Earth’s mass and an orbital period of
3 days. It is ten times closer to its star than Mercury is to our Sun.
Everyone agrees that “e” is hellish.
last zombies to emerge from the darkness were “f” and “g”, with “f”
being too cold for life, but “g” being right in the middle of the
habitable zone, the region where water is liquid.
Stephen Vogt of University of California at Santa Cruz is the lead author of the paper in the Astrophysical Journal
that announced the discoveries of “f” and “g”, based on 11 years of
observations using the mammoth 10-meter Keck telescope. In a TV
interview, Vogt proclaimed a “100%” probability of life on Gliese 581g,
and his paper says: “…our Milky Way could be teaming with potentially
habitable planets.” Indeed, Vogt estimated 1 in 5 stars have a habitable
on his findings, Vogt proposed a $100 million research program for his
field. When a science paper makes a pitch for money, one wonders if it’s
claims the probability of his analysis being wrong — the probability of
false-positive detections — is only: 1 in 400,000 for Gliese
581d; 1 in 100,000 for Gliese 581f; and 1 in 370,000 for the “100%-er”
The truth is, it’s very likely that none of these claimed exoplanets actually exist. Subsequent analysis, published in Science Magazine,
shows that Gliese 581 is a dynamic star. That variability, coupled with
its rotation, led to the erroneous “discovery” of three exoplanets that
actually don’t exist. This study shows that Gliese 581 truly has just
three planets, not six.
/ JPL / Caltech maintain the world’s official list of confirmed
exoplanets. They have removed Gliese 581’s ghost planets, retaining only
b, c, and e. Meanwhile, Vogt is sticking to his claims; he’s a true believer.
Scientific discovery is a rocky road best traversed with great persistence and healthy skepticism. It is easy to be blinded by exuberance,
self-confidence, and practical career pressures. Some will find what
they desperately seek, even if it isn’t there. Public media and some
journals eagerly publish spectacular claims, even without compelling
in the dogfight for funding, tenure, and prestige, scientists are
policed by other scientists eager to prove their “colleagues” wrong.
Earth and Artist’s Concept of the Non-Existent
Exoplanet with “100% Chance of Life”
Have a Happy & Safe Halloween!
October 30, 2014
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