Scientists Question the Existence of Planet Gliese 581g

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"Scientists Question the Existence of Planet Gliese 581g"
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In September 2010 astronomers set global society astir with announcements that the discovery of the first potentially habitable planet akin to Earth was found in the Libra the Scales constellation. This announcement was a dream come true for many who have actively been searching for signs of potential life outside of Earth's sphere.

The new planet, dubbed Gliese 581g, was proclaimed to be only 20 light years away from our planet and orbiting the previously discovered Gliese star. This confirmed red dwarf star, which has other known planets in its solar system from earlier discoveries, is considered to be relatively close when compared to other planets and celestial detections. This was an exciting announcement because most other discovered planets have, for the most part, been determined to not have the environmental climates to be habitable. Not so with Gliese 581g

In the report written by a team of astronomers working out of the W.M. Keck Observatory on Mauna Kea in Hawaii over the course of 11 years referred to Gliese 581g as the first "Goldilocks planet", meaning not too cold, not too hot, but "just right". This, in addition, to the fact that being the planet was determined to be a temperature zone that is conducive to the presence of water promoted the idea of possible extraterrestrial life. reported "The new planet, known as Gliese 581g, is at a distance that places it squarely in the middle of the star’s “habitable zone” where liquid water could exist on the planet’s surface.  If confirmed, this would be the most Earth-like exoplanet and the first bona fide potentially habitable one yet discovered."

Subsequently there were claims of discovered life on the newly discovered extrasolar planet along with skeptics; this was not surprising as this topic often naturally spurs debates about the possibility of extraterrestrial existence. However less than a month later, October 2010, scientists are now not only debating the existence of life on Gliese 581g, but disputing its existence period.

At the International Astronomical Union meeting, some experts expressed doubts about the discovery of Gliese 581g. Francesco Pepe, an astronomer who works out of the Geneva Observatory said that his team could not confirm the presence of Gliese 581g. In fact he took this a step further and said his team could not confirm Gliese 581f either, an earlier planet discovered. (via courtesy of MSNBC) states "The Geneva team, led by Michel Mayor, announced in 2009 the discovery of planet e in the Gliese 581 solar system.  At approximately 1.9 Earth masses, this e planet is the lowest mass extrasolar planet yet found, and has a 3.15-day orbital period around the star. Since Mayor's announcement in 2009 of the lowest-mass planet Gliese 581e, we have gathered about 60 additional data points with the HARPS instrument for a total of 180 data points spanning 6.5 years of observations, said Pepe. "From these data, we easily recover the four previously announced planets b, c, d, and e."

So where are planets f and g?

Apparently the dispute arises based out of the signals derived from space. explains that "multi-planet systems create a complicated signal, and astronomers must tease out the spectral lines to figure out what represents a planet, and what is just 'noise' "

Based on these factors Pepe and his team have searched for Gliese 581g and have determined they cannot tangibly provide confirmation to agree with the other team who announced the discovery of the planet. At this time no signals have emerged in this team's data sets which would bring about a concurrence in the existence of a Goldilocks planet.

This will undoubtedly be discussed for some time to come. Scientists have long been searching for life in outer space and are not likely to give up on the idea of finally finding a habitable planet.

Realistically there is still so much not yet known in space, the vast amount of it is mindboggling and full of uncertainty, however one thing is for certain, scientists are undoubtedly going to continue to search their quest with concrete proof of the Goldilocks planet.

Source: "Doubt cast on existence of possibly habitable alien planet",, October 12, 2010

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