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Continued Mystery from Tabby’s Star

A year ago Tabby’s Star (officially known as KIC 8462852) made headlines when a scientific paper was published in arXiv detailing possible phenomena that could account for the strange dips in brightness around the star. The most reasonable explanation seems to be that a swarm of cometary debris surround the star and produce unusual drop-offs in its luminosity.

None of the presented arguments, however, could explain all the things we were seeing and so the scientific community naturally continued looking for explanations.

Eventually, as is typical in this field, we reached a point where many started considering the possibility of intelligent life.

For those not “in-the-know” a Dyson Sphere is a hypothetical structure (made of solar panels or some such things) surrounding a star which absorbs most of said star’s energy. It’s thought a feat of astro-engineering like this could be the powerhouse for a massive, advanced civilization.

Such an object, some argue, could replicate the strange behavior of Tabby’s star.

Now there’s been another paper published that pretty much furthers the mystery.

Trends in the stars brightness over a long term period can be explained, but only at the neglect of the short term trends and vice versa. It’s as if the star adopts a certain personality for awhile, then another for a much longer period of time and then another.

A technical look at what’s happening is this: the star has had occasional drops in luminosity ranging from 15-22% which would equal something roughly half the radius of the star blocking its light (that’s huge, imagine a planet half the size of the Sun). Furthermore, a look at photographs ranging back to when astronomers had to use photographic plates in the 1800′s show that the star has dropped in luminosity about 20% overall since then.

Long story short: we don’t have an answer to whatever strange thing is happening over there. The science continues and the Kepler spacecraft will next observe the star in May 2017. 

SETI Institute has conducted tests for radio signals from the region of KIC 8462852 and have thus far found no evidence for intelligent life.

(Image credit: IPAC/NASA and STScl/NASA)

A new star, likely the brightest supernova in recorded human history, lit up planet Earth’s sky in the year 1006 AD. The expanding debris cloud from the stellar explosion, found in the southerly constellation of Lupus, still puts on a cosmic light show across the electromagnetic spectrum. In fact, this composite view includes X-ray data in blue from the Chandra Observatory, optical data in yellowish hues, and radio image data in red. Now known as the SN 1006 supernova remnant, the debris cloud appears to be about 60 light-years across and is understood to represent the remains of a white dwarf star. Part of a binary star system, the compact white dwarf gradually captured material from its companion star. The buildup in mass finally triggered a thermonuclear explosion that destroyed the dwarf star. Because the distance to the supernova remnant is about 7,000 light-years, that explosion actually happened 7,000 years before the light reached Earth in 1006. Shockwaves in the remnant accelerate particles to extreme energies and are thought to be a source of the mysterious cosmic rays.

Credit: NASA, ESA, Zolt Levay (STScl)

Time And Space

How could a galaxy become shaped like a ring? The rim of the blue galaxy pictured on the right is an immense ring-like structure 150,000 light years in diameter composed of newly formed, extremely bright, massive stars. That galaxy, AM 0644-741, is known as a ring galaxy and was caused by an immense galaxy collision. When galaxies collide, they pass through each other – their individual stars rarely come into contact. The ring-like shape is the result of the gravitational disruption caused by an entire small intruder galaxy passing through a large one. When this happens, interstellar gas and dust become condensed, causing a wave of star formation to move out from the impact point like a ripple across the surface of a pond. The intruder galaxy is just outside of the frame taken by the Hubble Space Telescope. This featured image was taken to commemorate the anniversary of Hubble’s launch in 1990. Ring galaxy AM 0644-741 lies about 300 million light years away.

Object Names: Ring Galaxy, AM 0644-741

Image Type: Astronomical

Credit: Hubble Heritage Team (AURA/ STScl), J. Higdon (Cornell), ESA, NASA

Time And Space

Behemoth supermassive black hole weighing 17 billion suns was found in an unlikely place: in the center of a galaxy in a sparsely populated area of the universe. The observations, made by our Hubble Space Telescope and the Gemini Telescope in Hawaii, may indicate that these monster objects may be more common than once thought.
This computer-simulated image shows a supermassive black hole at the core of a galaxy. The black region in the center represents the black hole’s event horizon, where no light can escape the massive object’s gravitational grip. The black hole’s powerful gravity distorts space around it like a funhouse mirror. Light from background stars is stretched and smeared as the stars skim by the black hole.

Credits: NASA, ESA, and D. Coe, J. Anderson, and R. van der Marel (STScI) [Computer Simulated Image]