Farewell, Opportunity: rover dies, but its hugely successful Mars mission is helping us design the next one

Opportunity in Endurance Crater. NASA

Andrew Coates, UCL
NASA’s Opportunity rover on Mars has been officially pronounced dead. Its amazingly successful mission lasted nearly 15 years, well beyond its initial three-month goal. Opportunity provided the first proof that water once existed on Mars and shaped its surface, a crucial piece of knowledge informing both current and future missions.
Opportunity landed on the red planet on January 25, 2004, and was last heard from on June 10, 2018, when a huge dust storm reduced light levels there significantly. This prevented the rover from using its solar panels to charge its batteries. The solar panels had already started to degrade due to the longer than expected mission, and the low light levels and the build up of dust may have caused its ultimate demise.
The rover has driven over 45km on the Martian surface despite being designed to travel for just 1km – an interplanetary record. Lasting almost 60 times its expected lifetime, it is an incredible achievement for space exploration. The mission is therefore helping scientists design new rover missions including NASA’s Mars 2020 rover and the ExoMars 2020 rover that I work on, recently named “Rosalind Franklin” after the DNA pioneer.

Stunning science

The science from the Mars exploration rovers Spirit and Opportunity has been simply groundbreaking. For Opportunity, it started with landing by chance in a 22-metre wide crater called “Eagle” on an otherwise mainly flat plain – a space exploration “hole in one”. Immediately after landing, it spotted a layered rocky outcrop, similar to sedimentary rocks on Earth but never before seen on Mars. And because it was mobile, it could actually examine the rock composition directly after leaving the landing platform.
By illuminating the rocks with radioactive sources, the rover discovered the expected iron (effectively rust) that makes Mars’ surface reddish brown, along with other metals such as nickel and zinc. But it also found more volatile elements like bromine, chlorine and sulphur, which indicated that these rocks may have reacted with ancient water. Most excitingly, it detected the mineral “jarosite”, which is often seen in the outflow of acidic water from mining sites on Earth. This provided direct evidence that acidic water had been involved in the formation of Mars’ rocks 3.8-4 billion years ago.
The rover then moved out of the Eagle crater onto the flat, surrounding plain. In the first weeks, it discovered “blueberries” – millimetre-sized spheres of the mineral hematite. Although this could have formed due to volcanism or meteor impacts, analysis revealed that it most likely formed in water.
Opportunity later visited the spectacular Victoria crater, which is 750 metres in diameter and some 70 metres deep, with dunes on the crater floor. Remarkably, the rover and its tracks were imaged from orbit by NASA’s Mars Reconnaissance Orbiter near the crater rim. There was more hematite here, too, showing that this may have formed underground in water, before being brought to the surface when the crater formed via an impact.

Opportunity at Victoria Crater spotted from orbit. NASA/JPL/University of Arizona

Its next destination was the Endeavour crater, which is 22km in diameter and 300 metres deep. Here it also made a major discovery –- there were clays near the crater rim, which would have required fresh, abundant and non-acidic water for their formation. This was the first indication that Mars was actually habitable 3.8-4 billion years ago, containing drinkable as well as acidic water.
These main science results are key to our scientific exploration of Mars today. The question of habitability is being pursued further by the NASA Curiosity mission, which has already found evidence of a large, ancient lake on early Mars that contained organic matter by drilling into the mudstones that remain.

Digging deeper

Thanks to Opportunity, upcoming missions will look closer at the spots were ancient water flowed. NASA’s Mars 2020 rover will gather samples from Jezero crater, a location where orbiters have detected signs of an ancient river delta. These samples may be returned to Earth by a future international mission. Analysis in labs on Earth may ultimately answer the question of whether there is or ever was life on Mars, if we haven’t already.

Opportunity outside Endeavour crater. NASA/JPL-Caltech/Cornell/Arizona State Univ. › Full image and caption

Meanwhile, our Rosalind Franklin rover, a collaboration between the European Space Agency and Russia, is due for launch in 2020. It will land in March, 2021, at Oxia Planum, an elevated plain. Here, there are also signs of prolonged exposure to ancient water, clays and a river outflow channel.
Rosalind the rover will pick up where Opportunity and Curiosity left off by examining a key, unexplored dimension on Mars – depth. We will drill down to two metres below the surface of Mars for the first time, much further than Curiosity’s five centimetres. This is enough to take us far enough below the harsh surface environment of Mars – with cold temperatures, a thin carbon dioxide atmosphere and high levels of harmful radiation – to see if anything lives there.
We will decide where to drill using a number of instruments, including the PanCam instrument which I lead. Samples will be vaporised and put into a drawer for analysis by three instruments which will look for markers of life – such as complex carbonates.
One of the key aspects of Opportunity’s success was the teamwork between its science and engineering teams. This is definitely something that will be implemented on upcoming rovers. Many members of the Mars 2020 team, and some on the ExoMars team, have direct experience from Opportunity which will be invaluable as we learn how to operate our rovers on the planet.
Another interesting legacy of Opportunity is that we we don’t have to worry too much about Martian dust, except during exceptional global storms. Opportunity showed that that during the rest of the time, accumulating dust blows away naturally in the wind – helped by the movement of the rover over the ground causing vibration. It was a surprise that Opportunity lasted so long, and it certainly blazed a trail for us.
Rosalind Franklin has the best chance of any currently planned mission for detecting biomarkers and even perhaps evidence for past or present life on Mars. But we are building on the shoulders of giants, like the Opportunity Rover. #ThanksOppy indeed!
Andrew Coates, Professor of Physics, Deputy Director (Solar System) at the Mullard Space Science Laboratory, UCL
This article is republished from The Conversation under a Creative Commons license. Read the original article.

How Ancient Cultures Explained Comets and Meteors

An artist’s rendition of 2016 WF9 as it passes Jupiter’s orbit inbound toward the sun.

Credits: NASA/JPL-Caltech

Eve MacDonald, Cardiff University
Comets and meteors have fascinated the human race since they were first spotted in the night sky. But without science and space exploration to aid understanding of what these chunks of rock and ice are, ancient cultures often turned to myth and legend to explain them.
The Greeks and Romans believed that the appearance of comets, meteors and meteor showers were portentous. They were signs that something good or bad had happened or was about to happen. The arrival of a comet could herald the birth of a great figure, and some people have even argued that the star in the sky which the Persian Magi followed to Bethlehem to see the newborn Jesus was actually a comet.
In the spring of 44BC, a comet that appeared was interpreted as a sign of the deification of Julius Caesar, following his murder. Caesar’s adopted son Octavian (soon to be the Emperor Augustus) made much of the comet, which burned in the sky during the funerary games held for Caesar. This portentous event was frequently celebrated in the ancient sources. In his epic poem, the Aeneid, Virgil describes how “a star appeared in the daytime, and Augustus persuaded people to believe it was Caesar”.

Augustus celebrated the comet and the deification of his father on coins (it did help to be the son of a god when trying to rule the Roman Empire), and many examples survive today.

Meteor showers

The Roman historian Cassius Dio referred to “comet stars” occurring in August 30BC. These are mentioned as among the portents witnessed after the death of the Egyptian queen Cleopatra. Experts are not entirely sure what it means when Dio uses the plural term “comet stars”, but some have connected this recorded event to the annual Perseid meteor shower.
Though it retains an ancient Greek name, we now know that the arrival of the Perseid meteor shower every August is actually the Earth’s orbit passing through debris from the Swift-Tuttle comet.


The meteor shower is named for the Perseidai (Περσείδαι), who were the sons of the ancient Greek hero Perseus. Perseus was a legendary figure with a fine family pedigree – he was the mythical son of Zeus and Argive princess Danaë (she of the golden rain). Perseus earned himself a constellation after a number of epic adventures across the Mediterranean and Near East that included the frequently illustrated murder of the Gorgon sister, Medusa.
Another of Perseus’s celebrated acts was the rescue of the princess Andromeda. Abandoned by her parents to placate a sea monster, the princess was found by Perseus on a rock by the ocean. He married her and they went on to have seven sons and two daughters. Sky watchers believed that the constellation Perseus, located just beside Andromeda in the night sky, was the origin of the shooting stars they could see every summer, and so the name Perseid stuck.

Tears and other traditions

In Christian tradition the Perseid meteor shower has long been connected to the martyrdom of St Lawrence. Laurentius was a deacon in the early church at Rome, martyred in the year 258AD, during the persecutions of the Emperor Valerian. The martyrdom supposedly took place on August 10, when the meteor shower was at its height, and so the shooting stars are equated to the saint’s tears.
Detailed records of astronomical events and sky watching can be found in historical texts from the Far East too. Ancient and medieval records from China, Korea and Japan have all been found to contain detailed accounts of meteor showers. Sometimes these different sources can be correlated, which has allowed astronomers to track, for example, the impact of Halley’s comet on ancient societies both east and west. These sources have also been used to find the first recorded observation of the Perseid meteor shower as a specific event, in Han Chinese records of 36AD.
Though the myths and legends may make one think that ancient civilisations had little scientific understanding of what meteors, comets and asteroids could be, this couldn’t be farther from the truth. The early astronomers of the Near East, those who created the Babylonian and Egyptian calendars, and astronomical data were – by far – the most advanced in antiquity. And a recent study of ancient cuneiform texts has proven that the Babylonian ability to track comets, planetary movements and sky events as far back as the first millennium BC involved a much more complex geometry than had been previously believed.
Eve MacDonald, Lecturer in Ancient History, Cardiff University
This article is republished from The Conversation under a Creative Commons license. Read the original article.


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Ancient Greek music: now we finally know what it sounded like

The God Apollon Playing The Cithara,
Marble, Miletus(Balat, Söke), Roman Period, 2nd. cen. AD.,
İstanbul Archaeological Museums.
Photo: @ancientpix

Armand D'Angour, University of Oxford

In 1932, the musicologist Wilfrid Perrett reported to an audience at the Royal Musical Association in London the words of an unnamed professor of Greek with musical leanings: “Nobody has ever made head or tail of ancient Greek music, and nobody ever will. That way madness lies.”

Indeed, ancient Greek music has long posed a maddening enigma. Yet music was ubiquitous in classical Greece, with most of the poetry from around 750BC to 350BC – the songs of Homer, Sappho, and others – composed and performed as sung music, sometimes accompanied by dance. Literary texts provide abundant and highly specific details about the notes, scales, effects, and instruments used. The lyre was a common feature, along with the popular aulos, two double-reed pipes played simultaneously by a single performer so as to sound like two powerful oboes played in concert.

Despite this wealth of information, the sense and sound of ancient Greek music has proved incredibly elusive. This is because the terms and notions found in ancient sources – mode, enharmonic, diesis, and so on – are complicated and unfamiliar. And while notated music exists and can be reliably interpreted, it is scarce and fragmentary. What could be reconstructed in practice has often sounded quite strange and unappealing – so ancient Greek music had by many been deemed a lost art.

But recent developments have excitingly overturned this gloomy assessment. A project to investigate ancient Greek music that I have been working on since 2013 has generated stunning insights into how ancient Greeks made music. My research has even led to its performance – and hopefully, in the future, we’ll see many more such reconstructions.

New approaches

The situation has changed largely because over the past few years some very well preserved auloi have been reconstructed by expert technicians such as Robin Howell and researchers associated with the European Music Archaeology Project. Played by highly skilled pipers such as Barnaby Brown and Callum Armstrong, they provide a faithful guide to the pitch range of ancient music, as well as to the instruments’ own pitches, timbres, and tunings.
Central to ancient song was its rhythms, and the rhythms of ancient Greek music can be derived from the metres of the poetry. These were based strictly on the durations of syllables of words, which create patterns of long and short elements. While there are no tempo indications for ancient songs, it is often clear whether a metre should be sung fast or slow (until the invention of mechanical chronometers, tempo was in any case not fixed, and was bound to vary between performances). Setting an appropriate tempo is essential if music is to sound right.

What about the tunes – the melody and harmony? This is what most people mean when they claim that ancient Greek “music” is lost. Thousands of words about the theory of melody and harmony survive in the writings of ancient authors such as Plato, Aristotle, Aristoxenus, Ptolemy, and Aristides Quintilianus; and a few fragmentary scores with ancient musical notation first came to light in Florence in the late 16th century. But this evidence for actual music gave no real sense of the melodic and harmonic riches that we learn of from literary sources.
More documents with ancient notation on papyrus or stone have intermittently come to light since 1581, and now around 60 fragments exist. Carefully compiled, transcribed, and interpreted by scholars such as Martin West and Egert Pöhlmann, they give us a better chance of understanding how the music sounded.

Ancient Greek music performed

The earliest substantial musical document, found in 1892, preserves part of a chorus from the Athenian tragedian Euripides’ Orestes of 408BC. It has long posed problems for interpretation, mainly owing to its use of quarter-tone intervals, which have seemed to suggest an alien melodic sensibility. Western music operates with whole tones and semitones; any smaller interval sounds to our ears as if a note is being played or sung out of tune.


But my analyses of the Orestes fragment, published earlier this year, led to striking insights. First, I demonstrated that elements of the score clearly indicate word-painting – the imitation of the meaning of words by the shape of the melodic line. We find a falling cadence set to the word “lament”, and a large upward interval leap accompanying the word “leaps up”.

Second, I showed that if the quarter-tones functioned as “passing-notes”, the composition was in fact tonal (focused on a pitch to which the tune regularly reverts). This should not be very surprising, as such tonality exists in all the documents of ancient music from later centuries, including the large-scale Delphic Paeans preserved on stone.

With these premises in view, in 2016 I reconstructed the music of the Orestes papyrus for choral realisation with aulos accompaniment, setting a brisk tempo as indicated by the metre and the content of the chorus’s words. This Orestes chorus was performed by choir and aulos-player at the Ashmolean Museum, Oxford, in July 2017, together with other reconstructed ancient scores.


It remains for me to realise, in the next few years, the other few dozen ancient scores that exist, many extremely fragmentary, and to stage a complete ancient drama with historically informed music in an ancient theatre such as that of Epidaurus.

Meanwhile, an exciting conclusion may be drawn. The Western tradition of classical music is often said to begin with the Gregorian plainsong of the 9th century AD. But the reconstruction and performance of Greek music has demonstrated that ancient Greek music should be recognised as the root of the European musical tradition.


Armand D'Angour, Associate Professor in Classics, University of Oxford
This article is republished from The Conversation under a Creative Commons license. Read the original article.

From washing machines to computers: how the ancients invented the modern world

A Sun Dial, Ephesus Museum.
Photo: instagram.com/ancientpix

Zena Kamash, Royal Holloway

True innovation is hard to find, as few things come out of nothing. Take the now ubiquitous selfie, for example. The format may have changed but the concept of making self-portraits is hundreds, if not thousands of years old. The same is true of many inventions that we typically think of as modern, some of which actually have precedents dating back over 1000 years.

A Roman washing machine

“Fulling” was a major occupation in the Roman world that involved cleaning cloth by trampling it in tubs containing an alkaline solution, such as water and urine or the mineral known as fuller’s earth. But in ancient Antioch, in what is now Turkey, evidence suggests the process may have been mechanised, meaning the Romans may have effectively created the world’s first washing machine as far back as the 1st century AD.
Traditionally thought of as a medieval invention, the mechanical fulling mill would likely have consisted of a waterwheel that lifted a trip-hammer, which would then drop to press the cloth. A fullers’ canal mentioned in an inscription in Antioch would have supplied an estimated 300,000m³ of water at almost a metre per second, far in excess of what was needed for regular foot-powered fulleries. The power this could generate means it could have supported fulling on an industrial scale with maybe 42 pairs of mechanical hammers.

An ancient Greek computer

In 1900, divers off the coast of the Greek island of Antikythera discovered something that changed our view of ancient science. The Antikythera mechanism is a bronze system of 30 gears that models the cycles of the sun and moon. It is effectively the first-known analogue computer, dating back to the 1st century BC. Set in a wooden box, the internal gears would have turned dials on the outside that showed the position of the sun and moon, as well as the rising and setting of specific stars and possibly the positions of Mars and Venus, too. Another dial could be moved to take into account leap years.
Although we now know that the Babylonians discovered how to use geometry to track the course of Jupiter in around 1800 BC, the Antikythera mechanism is the earliest known device that automatically calculates astronomical phenomena. We know of no other similiar devices for several hundred more years until the 8th century AD, when mathematician Muhammed al-Fazari is said to have built the first Islamic astrolabe. And nothing as mechanically sophisticated would appear again until the European astronomical clocks of the 14th century.

The Great Roman Bake-Off

Bread was big business in the Roman world. It was given out by the state as part of a dole known as the annona. This meant that it was possible for people to make substantial amounts of money as bakers. One such person was Marcus Vergilius Eurysaces, a freedman (ex-slave) from Rome, who was so proud of his successful baking business that he commemorated it on his tomb. Today it is one of the most striking monuments from ancient Rome.
The top of the monument is decorated with a series of scenes that show a range of baking activities including the mixing and kneading of dough, the forming of loaves and the baked loaves being stacked in baskets. The most curious part, however, is the cylinders that make up the bulk of the monument. These features have baffled scholars for quite some time. One convincing theory argues that it is likely that these cylinders are related to baking and may well represent an early dough-mixing machine. The idea is that a rotating metal arm would have been attached to each cylinder in order to mix the dough.

The first state space project

Ninth-century Baghdad in what is now Iraq saw the rise of a growing scientific community, particularly in astronomy, centred around a library known as the “House of Wisdom”. The problem for these new scholars was that their books were written many centuries earlier and came from a wide range of different cultures – including Persian, Indian and Greek – that did not always agree. The Caliph al Ma’mun decided the only solution was to build an astronomical observatory so the city’s scholars could determine the truth.
Observatories weren’t new but a state-sponsored scientific institution was. It’s hard to be sure exactly which instruments were used in the al-Shammasiyya observatory, but they probably included a sundial, astrolabes and a quadrant set on the wall to measure the precise position of objects in the sky. The quadrant may have been the first of its kind to be used in astronomical observations. The scientists used these instruments to reassess Ptolemy’s Mathematical Treatise from the 2nd century AD, and to make numerous astronomical observations, including the latitudes and longitudes of 24 fixed stars.

Zena Kamash, Lecturer in Roman Art and Archaeology, Royal Holloway
This article is republished from The Conversation under a Creative Commons license. Read the original article.

Now that TESS is Operational, Astronomers Estimate it’ll Find 14,000 Planets. 10 Could Be Earthlike Worlds in a Sunlike Star’s Habitable Zone

A new study from Thomas Barclay of NASA and the University of Maryland, Joshua Pepper at Lehigh University, and Elisa Quintana of NASA, has predicted TESS’s results. Barclay, Pepper, and Quintana ran their simulation 300 times to come up with their predicted yield. There’s a lot of detail in their results related to the type of star the planets orbit, the different observation mode used to detect which planets, and how it all relates to follow-up observations. But in a more brief form, here’s what the three researchers think TESS will find during its planned two-year mission:

• 14,000 total exoplanets
• 2100 of them will be smaller than 4 Earth radius (4R), 280 of those smaller than 2R
• 70 habitable planets orbiting red dwarf stars, 9 of them smaller than 2R
• 10 Earth-like worlds less than 2R which could be in the habitable zone of a star like our Sun

That’s a pretty exciting haul. 14,000 exoplanets, of which 10 could be Earth-like worlds in the habitable zone of a star like the Sun. It doesn’t mean that’s what TESS will find, but it should be a good approximation, and an intriguing one. Especially since, unlike Kepler, TESS’s exoplanets are prime targets for further observation and characterization.

Most exoplanets orbit red dwarf stars because they’re the most plentiful stars. This is an artist’s illustration of what the TRAPPIST-1 system might look like from a vantage point near planet TRAPPIST-1f (at right). Credits: NASA/JPL-Caltech

This isn’t the first yield simulation for TESS. But this one is done with real rather than simulated stellar population, so it should be more accurate. Another yield simulation from 2015 can be viewed here, and one from 2017 here.

The simulation yields show us that we’re likely to find Earth-like planets in habitable zones. Most of them will be orbiting red dwarfs, but a small number should be around Sun-like stars. This is what everybody wants to know.

But maybe more importantly, these simulations show us that TESS will meet its mission goal: to detect an abundance of planets smaller than Neptune that can be examined in follow up studies to determine their masses and atmospheric makeups.

In both cases, TESS is on track to deliver some solid results.

It was written by Evan Gough and originally published on Universe Today.

Roman gladiators were war prisoners and criminals, not sporting heroes

Venetio Relief, Roman Period, Nysa Ancient City, Aydın Museum.
Photo: instagram.com/ancientpix

Alastair Blanshard, The University of Queensland
For centuries, the bloody gladiator conflicts that the Romans staged in amphitheatres throughout the empire have engrossed and repelled us. When it comes to gladiators, it is almost impossible to look away. But the arena is also the place where the Romans feel most foreign to us.
The gladiator was the product of a unique environment. He can exist only within a very particular set of religious, social, legal, political and economic circumstances. It is not surprising that this is a form of spectacle we have not seen either before or since the Romans. To acknowledge this is also to acknowledge that they are only ever going to be partially comprehensible to us.

Sadly, this is not a view shared by the Queensland Museum, which last week opened its new exhibition, Gladiators: Heroes of the Colosseum. The exhibition brings together 117 objects from Italian museums, most notably the collection of the Colosseum at Rome. Highlights include some extremely well preserved and intricately decorated gladiatorial helmets and pieces of armour from Pompeii, as well as some very fine carved reliefs depicting scenes of combat.

Yet, while the quality of the individual objects is without question and certainly worth the price of admission alone, the intellectual framework of the exhibition is far more problematic.
This is not an exhibition that is plagued by doubts or uncertainties. It firmly knows who gladiators were and what they stood for – gladiators, the opening panel of the exhibition proclaims, were the “elite athletes” of the ancient world. The antique equivalent of today’s fighters in the popular sport MMA, if you like.

Sporting analogies pepper the exhibition. Spectators are routinely referred to as “fans” and the catalogue promises that this is an exhibition that “touches on many issues that have parallels with modern-day sport and sporting culture”.
At times, the exhibition also feels like it has taken its cues from contemporary video-game culture. The special weapons of the various types of gladiators are spelled out and visitors are invited to contemplate who would win between a gladiator fighting with a net (known as a retarius to the Romans) and one heavily armed (secutor). A video-game spin-off from the exhibition is easy to imagine.

Rogues not heroes

Gladiatorial combat was certainly popular among the Romans. Evidence for gladiators is found in every province of the Roman Empire.
These fights initially began as contests of matched pairs as part of funeral rites honouring the dead. However, over time their popularity grew. By the time of the Roman Empire, hundreds of gladiators might be involved in spectacles that could last as long as 100 days.
These games were never just displays of gladiatorial fighting. At their most elaborate they involved beast hunts with exotic animals, executions of criminals, naval battles staged in flooded arenas, musical entertainments and dances.
The Queensland Museum is not the first to try to understand gladiators as sporting heroes. However, this analogy causes more problems than it solves.
The vast majority of gladiators were either prisoners of war or criminals sentenced to death. Gladiators were the lowest of the low; violent murderers, thieves and arsonists. Even your most badly behaved football team at their most morally blind would have had no trouble in rejecting this crew.


Gladiators in Rome were regarded as fundamentally untrustworthy and outside of legal protection. It is more useful to think of gladiators as prisoners on death row than as David Beckham with a net and trident. The section in the exhibition where children are encouraged to dress up as gladiators would have appalled any respectable Roman parent (that said, it’s great fun).
The Queensland Museum can’t escape the lowly, servile and criminal origins of the gladiators, but it does attempt to moderate our opinion of them by suggesting that some free citizens wilfully chose to be gladiators in search of “eternal fame and glory”. In fact, the evidence of such citizen gladiators is extremely slim. It was almost certainly extreme desperation that forced them into the arena rather than a desire to be remembered by posterity.
At another point, the exhibition suggests that the crowd saw reflected in gladiators the virtues of the soldiers who guarded the empire. Such talk would have had any self-respecting Roman legionary reaching for his short sword.

Gods and monsters

Representing gladiatorial combat as sport also inevitably underplays the religious dimension of the fighting. The exhibition includes some fabulous tomb paintings from the city of Paestum, which illustrate the origins of gladiatorial combat in the funerary rites for the dead. These are wonderful works, which deserve to be much better known; however, they are a rare intrusion into an otherwise secular narrative.
Gladiatorial combats never stopped being religious events. Every day of the games would begin with a “solemn procession” with sacrifices on altars. The gladiators themselves were deeply implicated in the Roman theology of the divine, death, and the relationship between mortal and immortal. These spectacles were Roman sermons written in blood.

The final problem with focusing on gladiators as sporting heroes is that it tends to isolate their combat from the other elements that made up the games. Beast hunts and the executions of criminals were just as popular, possibly even more so. They were not precursors to the main event or entertainment for the intervals.
The executions of criminals could involve extravagant mythological tableaus. Prisoners were dressed as Hercules and burnt alive. The fatal flight of Icarus towards the sun might be re-enacted for the audience.

Certainly, these elaborate, gruesome affairs captured the attention of ancient writers far more than the gladiators who accompanied them. Wealthy Romans seemed far more preoccupied with obtaining suitably rare fauna for their spectacles.
For the poorer members of the audience, the beast hunts had an added attraction. Often the animal meat was distributed to the audience members to take home. They were literally watching their dinner being butchered in front of them.
One of the most intriguing items in the exhibition doesn’t relate to gladiatorial combat but to one of these beast hunts. It is a second-century CE mosaic that features what appears to be a female hunter facing off a giant tiger. Who is this woman? Evidence for female hunters (like female gladiators) is practically non-existent. Is she part of some mythological tableau? A woman pretending to be an Amazon? Or a man dressed up as a woman? Is this a scene from real life at all?
She is an enigma and a worthy reminder that the real secret of the appeal of Roman combat spectacle is that it raises more questions than it answers.

---

Gladiators: Heroes of the Colosseum will be on at the Queensland Museum until January 28 2018.
Alastair Blanshard, Paul Eliadis Chair of Classics and Ancient History Deputy Head of School, The University of Queensland
This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why did Tutankhamun have a dagger made from a meteorite?

Head of Tutankhamun, Met Museum.

Diane Johnson, The Open University

Scientists have long speculated that the ancient Egyptians used metal from meteorites to make iron objects. Now an analysis of a dagger found in Tutankhamun’s tomb has given us strong evidence that this was the case – and that the Egyptians knew the iron had come from the sky. But why did they use such an unusual source for the metal when there’s plenty of iron here on Earth?

Until recently, we didn’t think that the ancient Egyptians were particularly good at producing iron objects until late in their history, around 500 BC. There’s no archaeological evidence for significant iron working anywhere in the Nile Valley. Even the large amounts of iron-rich smelting waste products found in the Delta region could actually have been produced by attempts to make copper. When Tutankhamun died – 800 years earlier – iron was a rarer material than gold.

The most common natural source of metal iron on Earth is iron ores – rocks that contain iron chemically bonded to other elements. These need to be processed by heating them with other materials (smelting) to extract a low-quality form of iron, which is then beaten with hammers to remove impurities. This requires considerable know-how, effort and tools that we have no evidence for in ancient Egypt.

There were abundant supplies of iron ore in both Egypt and the Sinai peninsula and textual sources indicate that Egyptians were aware of the metal from early in their history. But the ore was mostly used to create pigments for art and make up. One explanation for this may be that the readily accessible iron ores were of poor quality so couldn’t be worked into more useful metal.

Interstellar source

But iron doesn’t just come from iron ore. We have evidence that numerous prehistoric societies worldwide which did not have access to ores or knowledge of smelting made use of metallic iron found in occasional meteorites. This precious gift from nature still required shaping into a useful form, often resulting in very basic iron objects, such as small thin metal pieces that could be used as blades or bent into shapes.

If ancient Egyptians knew that iron could be found in meteorites that came from the sky – the place of the gods – it may have been symbolically important to them. As a result, they could have seen all iron as a divine material that wasn’t appropriate to work into a practical, everyday form and that should be reserved only for high-status people.

Meteorites may have even played a more direct role in state religion. For example, the “Benben” stone worshipped in the sun temple of the god Ra at Heliopolis is thought to have possibly been a meteorite. The word “benben” is derived from the verb “weben”, meaning “to shine”.

The ancient language also offers clues as to how how iron was perceived by Egyptians – and that they knew meteorites were a source of the metal. The earliest hieroglyphic word for iron was greatly debated by translators, who frequently confused the words for copper and iron. The word “bi-A” was eventually translated as “iron”, but could easily have referred a range of hard, dense, iron-like materials.

The word was used in many texts including the funerary Pyramid Texts, early religious writings dating from approximately 2375 BC but likely to have been composed far earlier, carved on the internal walls of some pyramids. These textual references to iron connect it with aspects of the sky and with the bones of the dead king who will live for ever as an undying star in the sky.

From the beginning of the 19th Dynasty (approximately 1295 BC) a new hieroglyphic word for iron appeared: “bi-A-n-pt”, which literally translates as “iron from the sky”. Why this new word appears in this exact form at this time is unknown but it was later applied to all metallic iron. An obvious explanation for the sudden emergence of the word would be a major impact event or large shower of meteorites.

This would have been witnessed by much of the ancient Egyptian population, leaving little uncertainty as to where exactly the mysterious iron came from. One possible candidate event is the Gebel Kamil meteorite impact in southern Egypt. Although its exact date remains unknown, based upon nearby archaeology we know it occurred within the past 5000 years.

Ritual significance

Iron is also connected to ritual artefacts such as those used in the Opening of the Mouth ceremony, a ritual performed at the entrance of a tomb designed to transform the mummy into a latent being with the potential for life. Later texts, including temple inventories, that reference the equipment used in this ceremony refer to the iron blades used as “the two stars”. It may be that iron was allowed an important role in this ceremony because of the association of iron with meteorites, powerful natural phenomena whose own inherent power might increase the potency of the ritual.

We also know that iron dagger blades were important enough to be mentioned in diplomatic correspondence. The best-known example is a letter from King Tushratta of Mitanni (today in northern Iraq and Syria) detailing a dowry of his daughter who was to be sent as a bride to Tutankhamun’s grandfather, king Amenhotep III. This letter intriguingly refers to a dagger blade of “habalkinu”, a poorly documented word derived from the ancient Hittite language which some linguists have translated as “steel”.

Only further detailed analysis of the chemistry and microstructure of other artefacts will tell us if meteorites were a common source of the iron that the ancient Egyptians produced. We also need to determine when where and how the smelting of terrestrial iron ores started in Egypt to further guide us in our knowledge on the origins, evolution and specific techniques of ancient Egyptian metalworking technology. By combining this with our knowledge of the cultural importance of iron, we can start to develop a realistic understanding of the true value of this metal in ancient Egypt.

Diane Johnson, Post Doctoral Research Associate, Department of Physical Sciences, The Open University
This article is republished from The Conversation under a Creative Commons license. Read the original article.

Will China's moon landing launch a new space race?

What will China discover on the far side of the moon? BeeBright/Shutterstock.com

Wendy Whitman Cobb, Cameron University
China became the third country to land a probe on the Moon on Jan. 2. But, more importantly, it became the first to do so on the far side of the moon, often called the dark side. The ability to land on the far side of the moon is a technical achievement in its own right, one that neither Russia nor the United States has pursued.
The probe, Chang’e 4, is symbolic of the growth of the Chinese space program and the capabilities it has amassed, significant for China and for relations among the great power across the world. The consequences extend to the United States as the Trump administration considers global competition in space as well as the future of space exploration.
One of the major drivers of U.S. space policy historically has been competition with Russia particularly in the context of the Cold War. If China’s successes continue to accumulate, could the United States find itself engaged in a new space race?

China’s achievements in space

Like the U.S. and Russia, the People’s Republic of China first engaged in space activities during the development of ballistic missiles in the 1950s. While they did benefit from some assistance from the Soviet Union, China developed its space program largely on its own. Far from smooth sailing, Mao Zedong’s Great Leap Forward and the Cultural Revolution disrupted this early programs.
The Chinese launched their first satellite in 1970. Following this, an early human spaceflight program was put on hold to focus on commercial satellite applications. In 1978, Deng Xiaoping articulated China’s space policy noting that, as a developing country, China would not take part in a space race. Instead, China’s space efforts have focused on both launch vehicles and satellites - including communications, remote sensing and meteorology.
This does not mean the Chinese were not concerned about the global power space efforts can generate. In 1992, they concluded that having a space station would be a major sign and source of prestige in the 21st century. As such, a human spaceflight program was re-established leading to the development of the Shenzhou spacecraft. The first Chinese astronaut, or taikonaut, Yang Liwei, was launched in 2003. In total, six Shenzhou missions have carried 12 taikonauts into low earth orbit, including two to China’s first space station, Tiangong-1.
In addition to human spaceflight, the Chinese have also undertaken scientific missions like Chang’e 4. Its first lunar mission, Chang’e 1, orbited the moon in October 2007 and a rover landed on the moon in 2013. China’s future plans include a new space station, a lunar base and possible sample return missions from Mars.

A new space race?

The most notable feature of the Chinese space program, especially compared to the early American and Russian programs, is its slow and steady pace. Because of the secrecy that surrounds many aspects of the Chinese space program, its exact capabilities are unknown. However, the program is likely on par with its counterparts.
In terms of military applications, China has also demonstrated significant skills. In 2007, it undertook an anti-satellite test, launching a ground-based missile to destroy a failed weather satellite. While successful, the test created a cloud of orbital debris that continues to threaten other satellites. The movie “Gravity” illustrated the dangers space debris poses to both satellites and humans. In its 2018 report on the Chinese military, the Department of Defense reported that China’s military space program “continues to mature rapidly.”
Despite its capabilities, the U.S., unlike other countries, has not engaged in any substantial cooperation with China because of national security concerns. In fact, a 2011 law bans official contact with Chinese space officials. Does this signal a new space race between the U.S. and China?
As a space policy researcher, I can say the answer is yes and no. Some U.S. officials, including Scott Pace, the executive secretary for the National Space Council, are cautiously optimistic about the potential for cooperation and do not see the beginning of a new space race. NASA Administrator Jim Brindenstine recently met with the head of the Chinese space program at the International Astronautical Conference in Germany and discussed areas where China and the U.S. can work together. However, increased military presence in space might spark increased competition. The Trump administration has used the threat posed by China and Russia to support its argument for a new independent military branch, a Space Force.
Regardless, China’s abilities in space are growing to the extent that is reflected in popular culture. In Andy Weir’s 2011 novel “The Martian” and its later film version, NASA turns to China to help rescue its stranded astronaut. While competition can lead to advances in technology, as the first space race demonstrated, a greater global capacity for space exploration can also be beneficial not only for saving stranded astronauts but increasing knowledge about the universe where we all live. Even if China’s rise heralds a new space race, not all consequences will be negative.

Wendy Whitman Cobb, Associate Professor of Political Science, Cameron University
This article is republished from The Conversation under a Creative Commons license. Read the original article.

Rainfall clues link climate change to Maya collapse

Pyramid of the Magician in Uxmal, ancient Maya city. Yucatan, Mexico.
Image: Dreamstime.com - @Publicdomainphotos ID 116733902

Ancient Central American rainfall records suggest climate change was linked to the rise and fall of the Maya civilisation between AD 300 and 1000, a new study has found. Giant stone structures throughout the region hint at the strength of the Maya economy and its kings in its heyday, when plentiful rains led to an an abundance of food and a population explosion.The study, published today in the journal Science, compared rainfall patterns reconstructed from stalagmites inside Yok Balum Cave in Belize with historical clues carved into local monuments.
While rain brought prosperity, the drought that followed brought disaster.
“We propose that anomalously high rainfall favoured unprecedented population expansion and the proliferation of political centres between 440 and 660 C.E,” the authors wrote.
“This was followed by a drying trend between 660 and 1000 C.E. that triggered the balkanisation of polities, increased warfare, and the asynchronous disintegration of polities, followed by population collapse in the context of an extended drought between 1020 and 1100 C.E.”
The droughts were linked to crop failures, death, famine, and migration in Mexico, the study said.
“Over the centuries, the cities suffered a decline in their populations and Maya kings lost their power and influence,” lead author Dr Douglas Kennett, a professor of anthropology at Penn State University, said in a statement.
Dr Andrew Glikson from the Climate Change Institute and the School of Archaeology and Anthropology at the Australian National University said the new paper “builds up on previous studies, confirming a collapse of Maya civilisation due to combined regional warming and deforestation.”
“The ensuing severe droughts and agricultural collapse were caused by aggravation of natural warming trend due to extensive deforestation and thus loss of moisture, droughts and depletion of the ground water the Maya tapped from water holes,” said Dr Glikson, who was not involved in the study.
“The parallel with modern climate change is evident – global warming associated with deforestation, leading to droughts in extensive areas and floods in other regions.”
Sunanda Creagh, Editor, The Conversation
This article is republished from The Conversation under a Creative Commons license. Read the original article.

Claros Prophecy Centre

Claros(Prophecy Centre), a place where the concept of world citizenship adopted.Claros was an ancient Greek sanctuary on the coast of Ionia. It contained a temple and oracle of Apollo, honored here as Apollo Clarius. Claros, The Godhead God Apollo is one of the two important prophecy centers in Anatolia. İzmir is located at Menderes District at the base of Ahmetbeyli Valley, 13 km to the north of Kolophon and 2 km to the south of Notion.

There had been many applications this Prophecy Centre of Apollo Clarios from Anatolia(Bithynia, Mysia, Troas, Aiolis, Ionia, Lydia, Phygria ve Karia, Pisidia, Pamphylia, Paphlagonia, Cappodacia),Greece, Thrace, Macedonia, Islands(Such as Chios, Crete) and Syria Cities. In short, these applications could had been as individually or municipally from many parts of the Ancient World.

Alexander The Great applied to this center for the interpretation of a dream he had seen and set up the new town of Smyrna in Pagos upon receiving the answer that the new people to sit in Pagos would be 3-4 times more happy. Alexander's application to this center is the first individual application made here.Like the Hellenes, communities seen as Barbarians could apply to this center.This made Claros famous. It was a place where the concept of world citizenship is adopted.

Replicas of many statues found here is exhibited in this center. Many important figurines such as Artemis and homeros are in here. Original sculptures are in the surrounding museums. While you are walking here you can come across the foot pieces of the gigantic sculptures. There is entrance fee in Claros. If you visit during winter time, do not forget that some parts may be full of water because it is below the clathose floor. Since this city is in the Ionia region, you can also visit the neighboring cities which are Kolophon, Notion, Teos and Ephesus.

Alexander The Great

Alexander The Great, İstanbul Archaeological Museums.

Alexander The Great was King of Macedonia, Pharaoh of Egypt and Monarch of Asia.

Alexander was educated by the great philosopher Aristotle. Aristotle was a student of Plato whose teacher was Socrates. Aristotle, Plato and Socrates called as big three in philosophy. So Alexander had been equipped with the latest scientific ideas of the period, built in nearly a century, in 3 generations. He conceptualized the importance of science and philosophy.

His some interesting quotes about the one united world:

-This may originate from Plutarch's essay On the Tranquility of Mind, part of the essays Moralia: Alexander wept when he heard Anaxarchus discourse about an infinite number of worlds, and when his friends inquired what ailed him, "Is it not worthy of tears," he said, "that, when the number of worlds is infinite, we have not yet become lords of a single one?"

-There are no more other worlds to conquer!

The unification of all the nations of the world under one single state was a dream of him. He did not harm the religious temples which he captured, equated the Egyptian gods to the Greek gods and respected the cultures of other societies. His these features made him a popular ruler in lands outside of Macedonia.

Nearly Seventy cities were builded in new conquered lands and some of their names were Alexander. During his campaign he was taking along important people like scholars.

During the reign of his, Greek culture and greek language spread over a very wide area. Alexander became the pioneer of the Helenistic Period and prepared the foundations of the Roman Empire.

Alexander lost his life in Babylon at the age of 33. Without this surprise death, Our world would look very different from now. There could be the same language and religion in all other continents, except for the American continent in the world. Due to the importance given to informatics, maybe the world would not experience with medieval era. We could enter the industrial revolution era instead of entering the middle ages.

Teos Ancient City Olive Trees

Teos is located in Sığacık Neighborhood, Seferihisar District, İzmir Province of Turkey. It is one of the twelve Ionian Cities on the Aegean Coast and approximately 50 km away from the city center of Izmir. It can be reached by public transport. The entry to this ancient city is a fee and archaeological excavations continue in the ancient city. Dionysus temple, bouleuterion(council house), theater, cistern(fountain), acropolis, ancient port and ancient olive trees which are thousands years old must be seen. It is thought that this olive tree which I shot above and share with you is 1800 years old.

More than 200 old olive trees aged over 500-years-old are thought to be in the ancient city of Teos. The olive oil is obtained from these old trees by traditional methods in the lead of Seferihisar municipality. These oils are sold at auction held later. On October 16, 2017, auction was held for the second time under this 1800-year-old tree. Half a liter of olive oil, which can be obtained from this 1800 year old tree, was sold to 22 thousand Turkish liras (Approximately 6,000 American Dollars). This tree is located in the eastern of the Dionysus Temple in Teos Ancient City, a few hundred metres away from temple. In This auction, the oils were priced according to the age of the trees from which they were obtained. In total 137 liters of oil were sold to 49,200 Turkish Liras.

These olive trees are real monuments made by nature. These have bloomed for thousands of years and they continue to feed people. They saw Romans, Byzantines, Selchuks and Ottomans. Despite the fact that a lot of human beings generations have passed away from this world, they are still in the same place and alive like it was thousands of years ago. They are living witnesses in many historical events. I wish they could tell us what they saw.

1800 years old olive tree

Magnesia Ancient City

Magnesia Ancient City Stadion

Magnesia Ancient City reffered as "Magnesia ad Maeandrum" or "Magnesia on the Maeander". Maeander(Büyük Menderes) is a river where this city founded on one of the tributaries of Maeander. At the same time, Magnesia is a city which referred as Manisa Province of Turkey. A city called with its river helps to prevent misunderstanding. According to Strabo, Magnets founded Magnesia.

It is located in Tekin Village, Ortaklar Area, Germencik District, Aydın Province of Turkey. Magnesia nearly 80 km and 1 hour away from Adnan Menderes Airport in İzmir Province of Turkey. It is on the road between the Ortaklar and Söke. It was neighbour of crucial cities which included Ephesus, Priene and Tralleis Ancient Cities. 

The principal deity of the City is Artemis. There is a Temple and sacred area dedicated to Artemis. According to  Anciet Roman Period Writer Vitruvius, Architecture of Artemis Temple was Hermogenes, he was the first architect to apply the octagonal pseudodipteros temple plan. Vitruvius tells us that the main work of Hermogenes was the temple of Artemis Leukophryene in Magnesia. This temple was one of the greatest Artemis temples in Anatolia.

After walking around the sanctuary of Artemis, you can visit theatron, gymnasium and stadion, respectively. The City has one of the biggest stadions on the world. If you are going to this city, it is the stadion building you should definitely see. According to the entrance of the ancient city, the stadion remains far away. It may take some time to reach. The stadium is huge and magnificent. It has the capacity to allow monitoring of tens of thousands of people. The seats are made of marble. The city was known as the "city of races" due to many sports events were organized in antiquity times.

Swampy areas caused by alluviums carried by Maeander River led to formation of diseases, and the population gradually decreased over time. The artifacts found in Magnesia are exhibited in the Paris, Berlin and İstanbul Museums. Today, Archaeologiacal excavations continues in the city.