Mystery deepens around 'alien megastructure' star

The mystery surrounding a star previously linked to aliens continues to deepen.

The entity known as KIC 8462852 originally made headlines after scientists observed a range of unexplained light fluctuations being emitted from it.

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Since the occasional 20 percent drop in light can't be explained by normal means like a passing planet, one theory that has been proposed involves its periodic obstruction from a group of comets.

Another includes heavy construction activity by extraterrestrials who may be building what have been called "alien megastructures."

Now, Louisiana State University's Bradley Schaefer has determined that the star had dimmed by about a fifth in the period between 1890 and 1989 based on an examination of archived photographic plates at Harvard College Observatory.

He has called the fading output "completely unprecedented" for a star of that kind.

This finding largely discounts the comet theory since he estimates it would take 648,000 comets, each about 124 miles wide, to cause the effect.

According to him, aliens would also not be able to build enough to produce the outcome.

As such, more observation of the star is needed to explain its mysterious behavior.

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