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Pulsars: How The First ‘False Alien’ Signal Opened Up A New World In Astronomy

“In 1967, a radio source emitting regular, 0.04-second long pulses every 1.3373 seconds was found for the first time using a scintillation array. After the “noise” explanation was ruled out, the next thing people turned towards were intelligent extraterrestrials. There was no natural mechanism in existence that would have explained it at that time, so turning to aliens was logical, if ultimately incorrect.”

Observations that surprise us, of a phenomenon we weren’t expecting and don’t have an explanation for, are some of the most exciting things we can encounter in astronomy. In 1967, regularly pulsing radio sources, discovered without any expectation, provided exactly that. It wasn’t noise; it was definitely a robust, repeatable observation; so what was it? While our imaginations might have run to aliens initially, further developments quickly showed that this was a ball of rapidly rotating neutrons, more massive than even the Sun but only a few kilometers in diameter. These pulsars, as they’re now know, are ubiquitous and come about from the corpses of core-collapse supernova. Could this be a harbinger of what we can expect from the ‘alien megastructure’ controversy?

Come find out how the first ‘false alien’ signal from astronomy opened up a whole new field of science for us to investigate!

this atmospheric phenomenon is known as a circumhorizontal arc, which occurs when the sun is at least 58° above the horizon and the hexagonal ice crystals which form cirrus clouds become horizontally aligned.                     

(photos x, x, x, x, x, x, x. see also: more circumhorizontal arcs, asperatus clouds, mammatus clouds, polar stratospheric clouds and cloud iridescence)

Lightweight Black Hole

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Dancers in Light Blue (Rehearsing in the Dance Studio) by Edgar Degas

Medium: oil on canvas

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Massive Galaxy Cluster

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Archaeologists Discover Unknown Fortress Walls, Byzantine Gold Coin

Two unknown fortress walls and three unknown fortress towers as well as a 14th century Byzantine gold coin have been discovered by archaeologists during the 2016 excavations of the major medieval fortress of Rusocastro in today’s Southeast Bulgaria.

The Rusocastro Fortress is best known for the Battle of Rusocastro in 1332 AD. It was the last big military victory of the medieval Bulgarian Empire before it was conquered by the invading Ottoman Turks at the end of the 14th century.

It was also the last major battle of the seven-century-long Bulgarian-Byzantine Wars for domination of the Balkan Peninsula (lasting from the 7th until the 14th century), which ended when, weakened by their hostilities against one another, among other factors, Bulgaria and Byzantium were both conquered by the Ottoman Turkish invaders at the end of the 14th and the beginning of the 15th century. Read more.

The Pork Butcher by Camille Pissarro

Size: 66x54 cm Medium: oil on canvas

2017 January 14

Stardust in the Perseus Molecular Cloud Image Credit & Copyright: Lorand Fenyes

Explanation: Clouds of stardust drift through this deep skyscape. The cosmic scene spans nearly 2 degrees across the Perseus molecular cloud some 850 light-years away. A triangle of dusty nebulae reflecting light from embedded stars is captured in the telescopic field of view. With a characteristic bluish color reflection nebula NGC 1333 is at left, vdB13 at bottom right, and rare yellowish reflection nebula vdB12 lies at the top. Stars are forming in the Perseus molecular cloud, though most are obscured at visible wavelengths by the pervasive dust. Still, hints of contrasting red emission from Herbig-Haro objects, the jets and shocked glowing gas emanating from recently formed stars, are evident in NGC 1333. At the estimated distance of the molecular cloud, legs of the triangle formed by the reflection nebulae would be about 20 light-years long.

∞ Source: apod.nasa.gov/apod/ap170114.html

Yerres, Path Through the Old Growth Woods in the Park via Gustave Caillebotte

Size: 43x31 cm Medium: oil on canvas

Hubble Chases a Small Stellar Galaxy in the Hunting Dog

by NASA’s Marshall Space Flight Center   On a clear evening in April of 1789, the renowned astronomer William Herschel continued his unrelenting survey of the night sky, hunting for new cosmic objects — and found cause to celebrate! He spotted this bright spiral galaxy, named NGC 4707, lurking in the constellation of Canes Venatici or The Hunting Dog. NGC 4707 lies roughly 22 million light-years from Earth. NGC stands for “New General Catalogue of Nebulae and Clusters of Stars.” Over two centuries later, the NASA/ESA Hubble Space Telescope is able to “chase down” and view the same galaxy in far greater detail than Herschel could, allowing us to appreciate the intricacies and characteristics of NGC 4707 as never before. This striking image comprises observations from Hubble’s Advanced Camera for Surveys (ACS), one of a handful of high-resolution instruments currently aboard the space telescope. Herschel himself reportedly described NGC 4707 as a “small, stellar” galaxy; while it is classified as a spiral (type Sm), its overall shape, center, and spiral arms are very loose and undefined, and its central bulge is either very small or non-existent. It instead appears as a rough sprinkling of stars and bright flashes of blue on a dark canvas. The blue smudges seen across the frame highlight regions of recent or ongoing star formation, with newborn stars glowing in bright, intense shades of cyan and turquoise.