Controversial 'Goldilocks" Planets that Might Support Life Don't Actually Exist (VIDEO)
Is it too hot or too cold? For two "Goldilocks" planets, the conditions seemed just right; unfortunately, though, these planets don't exist. Scientists have unraveled the controversial signals coming from a dwarf star thought to be a prime target in the search of extraterrestrial life and have found that these signals don't come from planets, but instead come from events inside the star itself.
When astronomers hunt for exoplanets, they measure shifts in the pattern of a star's spectrum, the different wavelengths of radiation that it emits as light. These shifts can result from subtle changes in the star's velocity caused by the gravitational tugs of orbiting planets. Yet Doppler shifts of a star's "absorption lines" can also result from magnetic events like sunspots, which can give false clues of a planet that doesn't actually exist.
"This result is exciting because it explains, for the first time, all the previous and somewhat conflicting observations of the intriguing dwarf star Gliese 581, a faint star with less mass than our sun that is just 20 light years from Earth," said Paul Robertson, the lead author of the new study, in a news release.
The researchers actually showed that these planets didn't exist by analyzing Doppler shifts in existing observations of the star Gliese 581. The Doppler shifts that they looked at were the ones that were most sensitive to magnetic activity. In the end, they found that the signals attributed to the existence of two controversial planets disappeared.
"Our improved detection of the real planets in this system gives us confidence that we are now beginning to sufficiently eliminate Doppler signals from stellar activity to discover new, habitable exoplanets, even when they are hidden beneath stellar noise," said Robertson. "While it is unfortunate to find that two such promising planets do not exist, we feel that the results of this study will ultimately lead to more Earth-like planets."
The findings are published in the journal Science.
Want to learn more? Check out the video below, courtesy of YouTube.