Tabby's Star
Credit: NASA - JPL Caltech


We live in an amazing time when powerful computers are available, highly advanced space telescopes are active, and the average person still has the ability to contribute to science. In truth, these three benefits are all related to the development of powerful, and inexpensive, computers. They have combined to create the opportunity to solve a mystery.

KIC 8462852
This star in the Northern sky, was imaged by the Kepler Space Telescope during a mission to find distant planets. Unfortunately, it didn't meet the pattern and so it was rejected as a candidate system containing orbiting planets. That might have been the end of the story for "KIC" except for the existance of amateur astronomers.[1]

Planet Hunters
This online citizen group was established with the intent of finding planets that might be missed by the more sophisticated searching efforts. When "KIC" was checked by the group, they identified certain traits that were unusual. First, the light emitted was quite ordinary over the time span of available observations, indicating a plain sun. Next, however, significant drops in the amount of light did occur. This might have indicated the existence of a distant world, except there were several problems.

KIC 8462852Credit: 2MASS and GALEX

The Mystery

Too Much Light Loss

Tabetha Boyajian, and her team, reviewed the information found by the Planet Hunters. Indeed, the light from the star did dip significantly. While this might have been caused by an orbiting world, there was too much blockage. Jupiter, for example, causes the Sun to dim about 1%, for a distant observer. The "KIC" dimming was far higher. This could, theoretically, be caused by an object much larger than Jupiter. Unfortunately, such large objects would emit light, becoming stars themselves.

Not Regular Enough
The observation of the star found that there were occassional dips in brightness. There was, however, no pattern detected. Normally, bodies that pass in front of suns do so in a regular orbit. They can be observed as dimming over the course of several hours. The strange sun was dimmed for days at a time. As well, the dimming was not regularly timed. This would seem to rule out an orbiting body as the cause.

Not The Right Pattern

Next, the observation of the dimming over time showed that the pattern was unusual. Rather than doing so quickly, the process took days and even wavered at times. When the brightness was restored, it was not uniform, nor similar to the earlier dimming. No other occurrence showed such behavior.

Tabby's Star
Tabetha Boyajian, (Tabby) described KIC 8462852 as the most mysterious object in the universe. The observations did not match any others obtained by the Kepler Space Telescope. The mission had imaged about 150,000 stars over a rather long length of time. Tabby showed how no other set of data was like "her" star. Most others showed events that blocked starlight quickly, and regularly. All others showed much less significant blockages. Tabby's Star was mysterious, in many ways.

Potential Causes of Tabby's Star Behaviors

  • A large body, such as Jupiter or Saturn, might have blocked emissions from Tabby's Star. This theory, however, requires that such an object be many times more massive than any other ever detected. Such an object would emit various types of radiation which have not been detected.
  • A body located between Earth and Tabby's Star may have caused the effects. This theory can be ruled out because such a object would dim many other stars over time. Such events have not been detected.
  • The data may be faulty. This possibility was rigorously examined. Many thousands of observations obtained at the same time were not found to have any anomolies. Moreover, observations of Tabby's Star were taken over the course of several years. Only Tabby's Star showed these unique traits, among a group of 150,000 stars imaged during the mission

It has been theorized that an advanced alien culture may have established a mechanism that diverted starlight. This could potentially be observable as a reduction in emissions. Such an action has never been detected before and is beyond our ability. Various theories have been proposed that may match observed data. These all require the existence of a distant civilization, one that has never been previously detected anywhere, yet.

How You Can Help

There is a vital need to fully observe the next obscuring event. This is no longer possible with Kepler as it has moved on to other projects. Instead, other platforms must be used. A crowd funding effort is underway to obtain the money necessary to perform such observations. This represents the chance for regular people to help solve a mystery in space. Doubtless, the observations will be made in the coming decades, but the funding program will speed the process considerably. Over 1,300 backers have pledged to support observing missions. You can get involved as well with a contribution as low as $5.

What's Next?

Tabby mentions in her TED Talk that we know a lot about what this star is not. It is not a normal star being eclipsed by a planet, even one like Jupiter. It is not being obscured by dust or gas. It is not being blocked by a black hole. 

We need to fully observe another dimming event to obtain more data. This will give us the ability to develop more theories as to the cause. If we obtain the right information, we may even be able to theorize the correct cause. So far, all theories have been shown to have problems.

The crowd funding effort may be able to obtain the funds necessary to perform a long period of observations. This stands the greatest chance of being able to capture information during the next event. 

Amateur astronomers have also answered the call. They have pointed many telescopes to watch further developments. There is a good chance that one of these may identify an event shortly after it begins. Unfortunately, the information obtained is patchy and not easily correlated. Observations from one amateur astronomer may not be compatible with those from others. 

An organized, professional observing program is required. This can be arranged, but there are significant costs involved. The funding drive will obtain the necessary money and begin such a scientifically important program.

Tabby's Star is indeed mysterious. Out of 150,000 stars observed with a precision instrument, only this one exhibited such odd behaviors. All attempts to explain the cause have been proven inadequate. It is important that we increase the amount of data available in order that we may be able to find the true cause of the mystery.