Theories are only crap to those who do not present them.
RIK-210
A young star has been seen having episodes of dimming. The star is RIK-210 and it is around 472 light-years away from the Earth. A star will sometimes dim whenever an object would pass by it. That is how some planets have been found, by the dimming to causes to the star as it passes in front of it.
However, there is no planet near RIK-210 to explain for its dimming. It also doesn't have any nearby star that might cause it to be dim. RIK-210 is said to be around five to ten million years old and half as massive as the Sun.
http://www.itechpost.com/articles/66535/20161219/astronomers-find-star-mysteriously-dims.htm
https://arxiv.org/abs/1612.03907
https://phys.org/news/2016-12-astronomers-mysterious-dimming-young-nearby.html
RIK-210 is only 472 LY away from Earth and would be a better study to determine what is causing the light curve of KIC 8462.
The light curve variations of KIC - 8462 could be attributed to the remnants of late stage planet formations or an enshrouded protoplanet with an extended tail which are also theories that surround RIK-210 as well.
Not all alien mega structures would be neccessarily comprised of steel. An alien language could also be a mega structure.
https://phys.org/news/2016-12-astronomers-mysterious-dimming-young-nearby.html
I recently watched the movie Arrival very interesting movie if you know what you are looking for. This is an interesting theory to the light curves of several stars that have mysterious dims that cannot be explained.
Why were Sheena Easton sites used?....See...She....He...across the distance of the sea.
How an alien civilization might communicate with Earth.
The very first sense that a newborn uses upon emerging from the womb is its eyes as it encounters light for the very first time. An alien civilization having discovered Earth but not wanting to disturb our natural evolution would understand that the simple sense of sight would be a common language foundation or speech through seeing.
Hearing would be the second sense with touch and smell and taste to follow. But the two primary foundations of a language would be sight and hearing that like the letter A would form the legs of the letter A to a single point of understanding. The bar in the center of the letter A is to ensure that the rigidity of the foundation is remains connected at the simplest forms of communications and to not get to communicated with dual meanings of words.
In 1977 the Voyager program launched into space to explore what we call Deep Space, or the space beyond Pluto. On both of those spacecraft were Golden Records that described humanity and Earth and where Earth was located thus achieving the first foundation of communication between an alien civilization through sight.
An advanced alien civilization would know how sound is created based on a guide wavelength's, depth. width and length that would allow the aliens to understand what was on the record.
Like I mentioned sight is the first sense that an infant uses when it comes from the void into the light. Humans looking from the Earth into space is much like the infant seeing for its first time. An alien race would design its language based on sight first as a mutual understanding as a formal base of communication.
Because light travels very far and very fast through space and has a less likely chance to degrade across time and since sight is the first sense that we use an advanced civilization would use the largest source of light that we can see in space to communicate with.
A sun.
A sun emits light based on its own rhythm but there are several stars that are experiencing mysterious light curves or dims that cannot be explained as there is not any celestial objects interfering with the suns to cause the dims. The only explanation can be that something is manipulating the sun's light curve to create a language that humans can first see.
Stars that have mysterious dims that cannot be explained are:
RIK-210
EPIC-2042
KIC-8462
The closest sun is RIK-210 at approx 470 light years from Earth.
In all three mysteries the numbers, 0,1,2,4,6 and 8 are present in the first three and four numerical values.
All of these stars have dims that have increase mysteriously that much like the wavelength of sound can converted into sight at the speed of light.
Going back to the Golden Record and how a record is made. Each sound that is recorded on a record has left and right wave channel that the stylus travels across to create the desired the sound. If the light curves of the three suns listed above are treated like the wave channels where the length, depth and distance are converted into wave channels and a stylus then travels through both left and right wave channels then a message might be present that an advanced alien civilization is using to try and communicate with humanity.
The link below shows a record and stylus at 1,000 times magnification. If you look close enough at the outside edges of the wave channels a 2D wavelength is formed that is very much similar to how a light curve of a sun would look in 2D.
http://dangerousminds.net/comments/vinyl_and_stylus_at_1000x_magnification
If the light curves of the above three mysterious suns are placed together in various combinations such as the right channel of RIK-210 and the left channel of EPIC-2042 for example then the Golden Record of the aliens trying to communicate with humans might be present.