Something mysterious this way comes, in this instance, a star residing 1500 light years from earth, invisible to the naked eye but not to Kepler, the exoplanet explorer extraordinaire.
In 2011, several citizen scientists flagged one particular star as “interesting” and “bizarre.” The star was emitting a light pattern that looked stranger than any of the others Kepler was watching.
The light pattern suggests there is a big mess of matter circling the star, in tight formation. That would be expected if the star were young. When our solar system first formed, four and a half billion years ago, a messy disk of dust and debris surrounded the sun, before gravity organized it into planets, and rings of rock and ice.
But this unusual star isn’t young. If it were young, it would be surrounded by dust that would give off extra infrared light. There doesn’t seem to be an excess of infrared light around this star.
It gets better.
The unexplained signals have been found in data collected by Nasa’s Kepler Space Telescope. The mission was launched in 2009 and was designed to find planets by looking for the small dip in light caused when a planet passes in front of the star and blocks a small portion of the light.
It has been remarkably successful adding thousands of planets to the known roster. But in all the 150,000 stars that Kepler has monitored, none have ever looked like KIC 8462852. It stands out because the star dims so dramatically.
Whereas a planet will drop the light by a percent or two at most, this star dims by up to 20 percent. Also unlike a planet, which orbits the star and causes the drop to repeat, these dimmings took place at random intervals during the 1600 days that Kepler was monitoring the star.
Around the 800-day mark, the star’s light dropped by 15 percent, Then around the 1500-day mark, there was a flurry of dimming with one dropping 20 percent of the starlight. To fall that much, the object passing in front of the star must be almost half the diameter of the star. Yet Jupiter, the largest planet in our solar system, is only one-tenth the diameter of the Sun.
To rub salt into the wound, KIC 8462852, is estimated to be about 1.5 times larger than the sun, making the necessary object vast indeed. So it cannot be a planet.
Obviously far more research needs to be done to determine if this finding turns out to be actually true but in one sense, it reminds one of Larry Niven's SF classic Ringworld, a tale about how an advanced civilization could build tech able to harvest energy from a star at truly grand scale, something along the lines of what Kepler may have discovered.
They first travel to the Puppeteer home world, where they learn that the expedition's goal is to explore a ringworld: an artificial ring about one million miles (1.6 gigameters) wide and approximately the diameter of Earth's orbit (which makes it about 600 million miles (1,000 gigameters) in circumference), encircling a sunlike star. It rotates, providing artificial gravity that is 99.2% as strong as Earth's gravity through the action of centrifugal force. The ringworld has a habitable, flat inner surface equivalent in area to approximately three million Earth-sized planets. Night is provided by an inner ring of shadow squares which are connected to each other by thin, ultra-strong wire (shadow-square wire).
Another possibility could be the construction of a Dyson Sphere, a concept first articulated by famed SF writer Olaf Stapleton in Star Maker and popularized by Freeman Dyson.
A Dyson sphere is a hypothetical megastructure that completely encompasses a star and hence captures most or all of its power output. It was first described by Olaf Stapledon in his science fiction novel, Star Maker. The concept was later popularly adopted by Freeman Dyson. Dyson speculated that such structures would be the logical consequence of the long-term survival and escalating energy needs of a technological civilization, and proposed that searching for evidence of the existence of such structures might lead to the detection of advanced intelligent extraterrestrial life. Different types of Dyson spheres correlate with information on the Kardashev scale.