Tonight on NASA’s Unexplained Files – have aliens built a massive structure around a far off star, and what is moving on Pluto?
Two planets orbit a far off star, nothing unusual in that but these two are circling the star in a very strange manner. Scientists are puzzled that even one planet has managed to get into this weird orbit, never mind two of them.
It is a puzzle that has led to some suggesting that the planets may not be entirely natural.
Meantime, closer to home on planetoid Pluto there are strange things on the move, and what did the Apollo astronauts see when they headed to the moon…
The so called Death Star planets are not the only alien structure theory that has been running in the press recently.
Stars always have a catchy name and KIC 8462852 is no different, but this one has also been called the WTF (Where’s The Flux) star.
It’s an F-type main-sequence star and sits in the Cygnus constellation, 1,480 lightyears from Earth.
The Kepler space telescope has been busy over the last few years gathering data to help detect exoplanets. This is done by observing flux in the light from the star being examined. By analysing regular changes in the light levels scientists can work out what size a planet might be and in some cases even the makeup of its atmosphere.
On WTF or Tabby’s Star (named after the initial study’s main author) the unsual thing is that the changes in brightness are not the same each time and they are also much bigger than you’d expect from a planet.
Even something the size of Jupiter would only be expected to dim a star’s brightness by about 1 per cent. Whatever is causing the dimming on the WTF Star must be much bigger. It has dimmed between 15 and 22 per cent on different occasions. Astronomers think whatever is orbiting the star must be covering about half of it.
Theories range from several large planets with huge rings, large amounts of interstellar dust, a cloud of disintegrating comets or perhaps a recent asteroid field. Some have also suggested that the star might be younger than it seems so is still surrounded by coalescing material that will eventually form into planets.
However, none of these fit the data perfectly.
The other theory is that an alien race has constructed some sort of structure around the sun, maybe for energy harvesting.
Until the mystery is solved, SETI continues to take great interest in it, with a new search due to being in October this year.
Kepler is also due to study the star further in May 2017.
Watch NASA’s Unexplained Files tonight at 9/8c on Science Channel.More: NASA's Unexplained Files, Science Channel