News & Current Affairs

July 20, 2009

Space station toilet breaks down

Space station toilet breaks down

Toilet (Nasa)

The $100bn ISS has been blighted by toilet trouble

The main toilet has broken down on the International Space Station (ISS), currently home to a record 13 astronauts, Nasa said.

Mission Control told the crew to hang an “out of service” sign until the toilet can be fixed.

The crew of the shuttle Endeavour is confined to using the craft’s loo. ISS residents are using a back-up toilet in the Russian part of the station.

If repairs fail, Apollo-era urine collection bags are on hand, Nasa said.

“We don’t yet know the extent of the problem,” flight director Brian Smith told reporters, adding that the toilet troubles were “not going to be an issue” for now.

Bad plumbing?

The main toilet, a multi-million-dollar Russian-built unit, was flown up and installed on the US side of the space station last year.

ISS, July 17 (Nasa)

It had broken down once before, requiring a rush delivery of a replacement pump by the shuttle Discovery in 2008.

And another toilet-related row broke out earlier this year, when a Russian cosmonaut complained that he was no longer allowed to use the US toilet because of billing and cost issues.

Despite the latest housekeeping setback, astronauts managed to transfer spare parts from the shuttle Endeavour to the ISS on Sunday, the second day of a planned 11-day mission.

Nasa was also investigating why Endeavour’s tank shed an unusually large amount of insulating foam during its launch.

Advertisements

September 26, 2008

Team finds Earth’s ‘oldest rocks’

Team finds Earth’s ‘oldest rocks’

The rocks contain structures which might indicate life was present

Earth’s most ancient rocks, with an age of 4.28 billion years, have been found on the shore of Hudson Bay, Canada.

Writing in Science journal, a team reports finding that a sample of Nuvvuagittuq greenstone is 250 million years older than any rocks known.

It may even hold evidence of activity by ancient life forms.

If so, it would be the earliest evidence of life on Earth – but co-author Don Francis cautioned that this had not been established.

“The rocks contain a very special chemical signature – one that can only be found in rocks which are very, very old,” he said.

The professor of geology, who is based at McGill University in Montreal, added: “Nobody has found that signal any place else on the Earth.”

“Originally, we thought the rocks were maybe 3.8 billion years old.
The exciting thing is that we’ve seen a chemical signature that’s never been seen before
Prof Don Francis, McGill University

“Now we have pushed the Earth’s crust back by hundreds of millions of years. That’s why everyone is so excited.”

Ancient rocks act as a time capsule – offering chemical clues to help geologists solve longstanding riddles of how the Earth formed and how life arose on it.

But the majority of our planet’s early crust has already been mashed and recycled into Earth’s interior several times over by plate tectonics.

Before this study, the oldest whole rocks were from a 4.03 billion-year-old body known as the Acasta Gneiss, in Canada’s Northwest Territories.

The only things known to be older are mineral grains called zircons from Western Australia, which date back 4.36 billion years.

Date range

Professor Francis was looking for clues to the nature of the Earth’s mantle 3.8 billion years ago.

He and colleague Jonathan O’Neil, from McGill University, travelled to remote tundra on the eastern shore of Hudson Bay, in northern Quebec, to examine an outcrop of the Nuvvuagittuq greenstone belt.

The rocks turned out to be far older than first thought

They sent samples for chemical analysis to scientists at the Carnegie Institution of Washington, who dated the rocks by measuring isotopes of the rare earth elements neodymium and samarium, which decay over time at a known rate.

The oldest rocks, termed “faux amphibolite”, were dated within the range from 3.8 to 4.28 billion years old.

“4.28 billion is the figure I favour,” says Francis.

“It could be that the rock was formed 4.3 billion years ago, but then it was re-worked into another rock form 3.8bn years ago. That’s a hard distinction to draw.”

The same unit of rock contains geological structures which might only have been formed if early life forms were present on the planet, Professor Francis suggested.

Early habitat?

The material displays a banded iron formation – fine ribbon-like bands of alternating magnetite and quartz.

This feature is typical of rock precipitated in deep sea hydrothermal vents – which have been touted as potential habitats for early life on Earth.

“These ribbons could imply that 4.3 billion years ago, Earth had an ocean, with hydrothermal circulation,” said Francis.

“Now, some people believe that to make precipitation work, you also need bacteria.

“If that were true, then this would be the oldest evidence of life.

“But if I were to say that, people would yell and scream and say that there is no hard evidence.”

Fortunately, geologists have already begun looking for such evidence, in similar rocks found in Greenland, dated 3.8 billion years.

“The great thing about our find, is it will bring in people here to Lake Hudson to carry out specialised studies and see whether there was life here or not,” says Francis.

“Regardless of that, or the exact date of the rocks, the exciting thing is that we’ve seen a chemical signature that’s never been seen before. That alone makes this an exciting discovery.”

August 26, 2008

Huge statue of Roman ruler found

Huge statue of Roman ruler found


Marcus Aurelius ruled over the empire for 19 years

Parts of a giant, exquisitely carved marble sculpture depicting the Roman emperor Marcus Aurelius have been found at an archaeological site in Turkey.

Fragments of the statue were unearthed at the ancient city of Sagalassos.

So far the statue’s head, right arm and lower legs have been discovered, high in the mountains of southern Turkey.

Marcus Aurelius was portrayed by Richard Harris in the Oscar-winning 2000 film Gladiator and was one of the so-called “Five Good Emperors”.

He reigned from 161AD until his death in 180AD.

In addition to his deeds as emperor, Marcus Aurelius is remembered for his writings, and is considered one of the foremost Stoic philosophers.

The partial statue was unearthed in the largest room at Sagalassos’s Roman baths.

The cross-shaped room measures 1,250 sq m (13,500 sq ft), is covered in mosaics and was probably used as a frigidarium – a room with a cold pool which Romans could sink into after a hot bath.

It was partially destroyed in an earthquake between 540AD and 620AD, filling the room with rubble. Archaeologists have been excavating the frigidarium for the past 12 years.

The dig is part of wider excavations at the ruined city, which was once an important regional center.

Imperial gallery

Last year, the team led by Prof Marc Waelkens, from the Catholic University of Leuven in Belgium, uncovered fragments of a colossal marble statue of the emperor Hadrian in the rubble.

This month, the researchers found a huge head and arm belonging to Faustina the Elder – wife of the emperor Antoninus Pius.

Archaeologists now think the room hosted a gallery of sculptures depicting the “Antonine dynasty” – rulers of Spanish origin who presided over the Roman Empire during the second century AD.

Foot of Marcus Aurelius statue (Sagalassos Archaeological Research Project)

The emperor wore army boots decorated with lion skins

Early on 20 August, a huge pair of marble lower legs, broken just above the knee, turned up in the debris.

They also found a 1.5m-long (5ft-long) right arm and hand holding a globe which was probably once crowned by a gilded bronze “Victory” figure.

But it was the giant marble head which identified this statue as the young Marcus Aurelius. The colossal head, which is just under 1m (3ft) in height, is said to bear his characteristic bulging eyes and beard.

Prof Waelkens said the pupils were gazing upwards “as if in deep contemplation, perfectly fitting of an emperor who was more of a philosopher than a soldier”.

He added that this was one of the finest depictions of the Roman ruler.

The emperor wore exquisitely carved army boots decorated with a lion skin, tendrils and Amazon shields.

The torso was probably covered in bronze Armour filled inside with terracotta or wood. When the niche’s vault collapsed in the earthquake, the torso would have exploded.

Bath complex

The statue of Hadrian was found lying halfway down in the frigidarium‘s rubble.

This initially led archaeologists to think it had been hauled in there from another part of the huge bath complex, perhaps to remove its gilded bronze armour, or to burn the huge marble pieces to make cement in a nearby lime kiln.

However, they now think sculptures of Hadrian, his wife Vibia Sabina, another Roman emperor Antoninus Pius, his wife Faustina the Elder, and Marcus Aurelius all once adorned niches situated around the room.

There were three large niches on both the western and eastern sides. The fragments of Hadrian’s statue were found near the south-west niche.

The front parts of two female feet were discovered in the opposite niche, on the room’s south-eastern side.

Arm and hand of Marcus Aurelius (Sagalassos Archaeological Research Project)

The remains of a globe can still be seen, cupped in the right hand

The archaeologists now think these belonged to a colossal figure of Vibia Sabina, who was forced into marriage with the homosexual Hadrian at the age of 14.

Remains of the statue depicting Faustina the Elder were found further along, on the eastern side.

In the opposite niche, they found the front parts of a pair of male feet in sandals, which could belong to her husband, Antoninus Pius – who succeeded Hadrian as emperor.

The experts suggest Antonine emperors occupied niches on the western side of the room, while their spouses stood opposite, on the east side.

Five good emperors

After the discovery of Faustina and her male counterpart, the archaeologists guessed the north-western niche would contain a colossal statue of Marcus Aurelius – the longest-surviving successor of Antoninus Pius.

The discovery on Wednesday confirmed this prediction, and suggests the north-eastern niche may contain remains of a statue depicting Faustina the Younger, Marcus Aurelius’s wife.

Archaeologists will get the opportunity to excavate this part of the room next year.

Lower legs of Marcus Aurelius statue (Sagalassos Archaeological Research Project)

The statue of Marcus Aurelius stood in the north-western niche

Despite his philosophical leanings, Marcus Aurelius had to spend much of his reign fighting Germanic tribes along the Austrian Danube where, inĀ  180AD, he died in nearby Carnuntum.

The part of Marcus Aurelius in Gladiator was one of Richard Harri’s last roles (the actor died in 2002). Although much of the storyline is fictional, it is set against an historical backdrop of the imperial succession from Marcus Aurelius to his son Commodus.

While Marcus Aurelius is considered, along with Nerva, Trajan, Hadrian and Antoninus Pius, as one of Rome’s Five Good Emperors, Commodus’s reign was marked by internal strife, cruelty and conspiracies.

Commodus took part, naked, in gladiatorial battles – which he always won. Opponents, whose lives were apparently spared, would eventually submit to the emperor.

He was murdered in 192AD – not by a general called Maximus, but by an athlete named Narcissus, sent by conspirators to strangle the megalomaniac emperor in his bath.

Blog at WordPress.com.