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BEIJING, Sept. 6 (Xinhuanet) -- The amount of space junks floating in Earth's orbit has reached a critical level, warned scientists.The future space missions may become too dangerous to fly for a risk of colliding with space junks, said a report released recently by the U.S. National Research Council (NRC).The kinds of space junks range from huge, the report said, there are thousands of discarded satellites and rocket boosters and countless tiny pieces of daily gabages from space missions.The debris are traveling in orbit at 17,500mph, at such a speed even a tiny clash can destroy a spacecraft.The NRC recommended that NASA should launch a plan to clean up the floating debris and called on other major space nations' cooperation."The current space environment is growing increasingly hazardous to spacecraft and astronauts," said Kessler, an ex-NASA researcher, "NASA needs to determine the best path forward for tackling the multifaceted problems caused by meteoroids and orbital debris that put human and robotic space operations at risk."

RAMALLAH, Aug. 26 (Xinhua) -- China's special envoy to the Middle East, Wu Sike, said here Friday that his country fully supports the Palestinians' right to establish an independent state in a balanced manner and through peace talks."China supports the Palestinian people and their cause. We also support the Palestinians to get the United Nations recognition of a Palestinian state on the lands occupied in 1967 with Jerusalem as capital," he told Xinhua in Ramallah.The envoy said peace talks with Israel are the best way to reach a settlement, adding that gaining UN recognition is not an alternative to peace negotiations.China supports a two-state solution -- Israel and an independent Palestinian state living side-by-side in peace and security, he said, noting that he believes the current developments in the Middle East have a positive impact on the Palestinian cause."The Middle East witnesses many changes. People have many chances to participate in political life. The Palestinian cause is a main issue that attracts the attention of the Arab people," he said."The recent meeting of the Arab League Peace Initiative Follow- Up Committee in Qatar assures the Arabs' support to the Palestinians' bid for full UN membership," he said. "This will help the Palestinians gain more international support."The Palestinians say they will approach the UN in September to get full membership of the world body as peace talks with Israel have long been deadlocked, a move disapproved by Israel and the United States.Wu expressed his appreciation of the reconciliation deal signed between Palestinian National Authority President Mahmoud Abbas' Fatah party and Hamas movements in Cairo in May."This move will help the Palestinians to have more countries on their side," he said.Wu said his Middle East tour was taking place at an important moment as the region is witnessing crucial changes, stressing that China respects the choices of the peoples."The Arab peoples are able to make their own decisions toward development," said the envoy.He also said the ties between China and the Arab countries are based on strong foundations, regardless of the changes taking place in the region.Wu met with Palestinian President Mahmoud Abbas and other officials Tuesday, the first day of his ongoing Middle East tour.This was Wu's second visit to Palestinian territories this year, after which he will travel on to Israel, Egypt and France.

BEIJING, Sept. 14 (Xinhuanet) -- Scientists had discovered the fossils of a new species of ancient carnivorous fish, National Geographic reported Monday.The newly-found ancient fish, "Laccognathus embryi", is a 1.8-meter-long predator, which was "waiting to lunge out to grab whatever was in front of it," said study co-author Ted Daeschler, a vertebrate zoologist at the Academy of Natural Sciences in Philadelphia, the U.S..It had a jaw filled with sharp teeth that were 1.5 inches long, the Journal of Vertebrate Paleontology described.The fish lived in the Devonian period, 415 to 360 million years ago, which "was a fish-eats-fish kind of world," Daeschler said. "There was a real arms race going. If you didn't have good armor on your body, you were very vulnerable.""It's not just finding the animal - it's also placing the animal in its evolutionary crucible," Daeschler added.Its closest living relative is the lungfish which can survive in the drought, scientists said.Scientists hope the finding can help in their study on the revolution of fishes as well as other species.

CANBERRA, Aug. 31 (Xinhua) -- Australia's new chief medical officer, Professor Chris Baggoley, on Wednesday said Australian should not be worried about reports that a mutant strain of the deadly bird flu virus is spreading across Asia and beyond.On Monday, the UN's Food and Agriculture Organization (FAO) said a mutant strain of the deadly avian influenza virus was spreading in Asia and issued a warning that the bird flu could spread from poultry to humans. It urged "heightened readiness and surveillance" as the mutant strain posed "unpredictable risks to human health."But Professor Baggoley, who took office on Tuesday, said Australia is well served by strict testing and customs regimes, adding that avian migration patterns also mean infected birds are highly unlikely to arrive in Australia."I don't think we should be worried," Prof Baggoley told Sky News."The country and the Australian government is certainly vigilant in relation to bird flu."Prof. Baggoley insisted the H5N1 virus remains overwhelmingly a disease of birds and it is very uncommon for humans to catch it. It is also exceedingly rare for humans to spread it among themselves.He said that even if bird flu did arrive and affected humans, Australia is ready to respond to any new and significant developments in bird flu."Australia tests migratory wild birds, looking for H5N1, and has been doing this for some years and has never found it," he said."On the human side of things, Australia has been preparing for a possible outbreak of H5N1 since 2004."We've got the laboratory capacity to diagnose influenza; we've got arrangements in place for a rapid production of an H5N1 vaccine for humans, and we've got ready access to antivirals."There have been no outbreaks of bird flu in Australia to date.The UN said the latest human death from bird flu occurred earlier this month in Cambodia, which has registered eight cases of human infection this year, all of them fatal.H5N1 has infected 565 people since it first appeared in 2003, killing 331.

CANBERRA, Aug. 17 (Xinhua) -- Australian scientist on Wednesday said his international research team has discovered the trick on how butterfly learn to change its wing pattern to avoid being eaten by birds.The Amazonian butterfly, Heliconius numata, has learnt to carry out a single genetic switch to alter its wing pattern so it appears to be another bad-tasting butterfly that birds will avoid.Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at Australia's University of Melbourne was part of the international research team, which was led by scientists at Centre National de la Recherche Scientifique (CNRS) and the University of Exeter in United Kingdom.Dr. Lee said the historical mystery had puzzled researchers for decades."Charles Darwin was puzzled by how butterflies evolved such similar patterns of warning coloration," Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at the University of Melbourne told Western Australia Today."We have now solved this mystery, identifying the region of chromosome responsible for changing wing pattern."He said the research team identified a genetic switch known as a supergene, which allowed the butterfly to morph into several different forms, allowing one species to mimic another."It is amazing that by changing just one small region of the chromosomes, the butterfly is able to fool its predators by mimicking a range of different butterflies that taste bad," he said."The butterflies rearrange this supergene DNA like a small pack of cards, and the result is new wing patterns. It means that butterflies look completely different but have the same DNA."There are other butterflies doing similar tricks, but this is the most elegant one."I was just fascinated by how elegant they were."He said the discovery proves that small chromosomal changes can preserve successful gene combinations, and thus help a species to adapt.The findings of the study are published on August 14 in the international journal Nature.

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