PpigScience: history

Showing posts with label history. Show all posts

February 09, 2018

New Horizons claims record for most distant images in history of space exploration

False-color images of KBOs 2012 HZ84, taken by the New Horizons spacecraft(Credit:NASA/JHUAPL/SwRI)

NASA's New Horizons spacecraft has returned some magnificent images of the Solar System's outer reaches around Pluto, its primary target. Its latest snaps may not be its most spectacular, but are pioneering in their own way as the farthest images ever snapped away from the Earth.

New Horizons grabbed the below black and white photo as it turned its Long Range Reconnaissance Imager (LORRI) toward a cluster of stars known as the Wishing Well, which are around 1,300 light years away from Earth. The craft itself was zipping through space around 3.79 billion miles from Earth, further away than the Voyager 1 spacecraft when it snapped the iconic Pale Blue Dot image in 1990 at a distance of 3.75 billion miles.

Image of the Wishing Well star cluster, snapped by the New Horizons spacecraft

But this record didn't stand for long. In fact New Horizons broke it again two hours later when LORRI was turned toward Kuiper Belt objects 2012 HZ84 and 2012 HE85, the closest ever images of Kuiper Belt objects. And with the probe continuing to hurtle through space at a speed of 700,000 miles (1.1 million km) per day, it will continue to collect more and more distant views of the universe.

The New Horizons spacecraft is said to be in good condition and is currently hibernating, with mission control planning to awaken it again on June 4 in preparation for a flyby of Kuiper Belt object 2014 MU69 in mid-2019. Continuing with the theme, this will be the most remote flyby in the history of robotic space exploration.

The New Horizons team turned its attention to the Kuiper Belt once its work circling Pluto was complete, specifically targeting 2014 MU69. Observations made by the Hubble Space Telescope and ESA's Gaia missionlast year revealed that the object may be shaped like a stretched out American football or even possibly be two separate bodies, configurations scientists described as "provocative" and a potential "scientific bonanza." All will be revealed in due course.

Source: NASA

February 05, 2018

Ancient Egyptian "billboard" could rewrite history of hieroglyphs

by Unknown, in science

The newly-discovered rock inscriptions show, from right to left, a bull's head on a pole, two storks back to back and an ibis in between them(Credit: Yale University)

Archaeologists from Yale and the Royal Museums of Art and History in Belgium have discovered an ancient Egyptian "billboard" that might turn back the clock on when the hieroglyphic writing system was thought to be introduced to the general population. The huge inscriptions date back to about 3,250 BCE, and show a form of writing that was thought to only be used by the ruling class at that time.
The new writings were discovered on a hill in the desert of Elkab, which was a bustling area in ancient Egypt. While the hieroglyphs were widely known from tokens and labels at the time, it was thought that the written symbols were mostly used for bureaucratic purposes. But here they were, scrawled across a rock face along a well-traveled route like a road sign, indicating that the general public may have had access to writing earlier than previously thought.
"This newly discovered rock art site of El-Khawy preserves some of the earliest — and largest — signs from the formative stages of the hieroglyphic script and provides evidence for how the ancient Egyptians invented their unique writing system," says John Coleman Darnell, Yale professor and co-director of the Elkab Desert Survey Project. "This also suggests that there is a much more expansive use of the early writing system than is indicated from other surviving archaeological material."
Apparently, the team was "absolutely flabbergasted" by the discovery, due mostly to the size of the symbols. Where most are usually only a centimeter or two tall, these hieroglyphs measured more than 50 cm (20 in) and were carved into a tableau about 70 cm (27.6 in) tall.

Professor John Darnell is the co-director of the expedition(Credit: Yale University)

"This discovery isn't new in the sense that this is the first time that anyone has seen these hieroglyphs; this is the first time that anyone has seen them on such a massive scale," says Darnell. "In the modern world this would be akin to seeing smaller text on your computer screen and then suddenly seeing very large ones made the same way only on a billboard."
The tableau is made up of four signs written right to left, which would become the dominant writing direction found in later Egyptian texts. The signs include a bull's head on a pole, two saddlebill storks standing back to back, with a bald ibis between them. These symbols are often seen in this formation in later texts that describe the solar cycle and luminosity, and according to Darnell, they may "express the concept of royal authority over the ordered cosmos."
The researchers are making use of new techniques to record the sites, by building 3D images out of photographs.

Source: Yale, NewAtlas

December 06, 2017

Iron tools from the Bronze Age found to have otherworldly origins

by Unknown, in world

A new study has found that all iron tools from the Bronze Age, including King Tutankhamun's dagger, were made from meteoric metal(Credit: University of Pisa)

A weapon as legendary as the dagger of King Tutankhamun needs an epic backstory, and last year X-ray analysis showed that the iron in the ancient blade had come from meteorites. Now, a French study has found that the artifact was far from alone as all iron tools dating back to the Bronze Age have otherworldly origins.

Beginning around 3300 BCE in the Near East and parts of South Asia, the Bronze Age was categorized by the widespread use of bronze in weapons, tools and decorations. Made by smelting copper and mixing it with tin, arsenic or other metals, bronze was durable and relatively easy to come by, and as such it remained the top choice until it was supplanted when the Iron Age began some 2,000 years later.

That's not to say that iron wasn't used during the Bronze Age – on relatively rare occasions iron artifacts have been found dating back to before the Iron Age, but it was much harder to come by and work with. The trouble was, most of the metal was locked in ore and needed to be smelted at extremely high temperatures, which was beyond the technological capabilities of the time. So where did those early iron artifacts come from?

It's long been thought that iron tools of the time were made from meteorites, which would have deposited the metal in an already-workable state on the Earth's surface. The theory would explain the presence of iron in artifacts before the advanced smelting techniques had been developed, and whether or not their owners knew that the metal was not of this planet, iron would have been prized for its relative rarity.

To determine whether these early iron artifacts were of terrestrial or extraterrestrial origin, Albert Jambon from the the National Center for Scientific Research (CNRS) in France conducted chemical analyses of several Bronze Age samples. Along with King Tut's dagger, Jambon studied a bracelet and headrest belonging to the Egyptian king in 1350 BCE, axes from Syria and China dating back to about 1400 BCE, a Syrian pendant from 2300 BCE, a Turkish dagger from 2500 BCE, and beads from Gerzeh, Egypt, which stretch right back to 3200 BCE, just after the Bronze Age began.

Jambon used a portable X-ray fluorescence spectrometer, an instrument that can determine the elements that make up a sample of rock or metal without damaging the target. Using this, Jambon could tell from the iron's impurities whether the metal in the relics came from meteorites or was naturally occurring on Earth. Iron meteorites usually contain higher levels of nickel and cobalt than Earthly iron due to the tendency for nickel to drift towards the molten core of a planet.

Sure enough, all of the tested samples had levels of nickel and cobalt that lined up with those seen in iron meteorites. Jambon concluded that essentially all iron items from the Bronze Age would therefore be made of meteoric iron, until the development of the smelting process that marked the beginning of the Iron Age from about 1200 BCE.