Archive for February 2008
The Encyclopedia of Life….
27. February 2008 by admin.
While it has taken almost a year, the non-profit Encyclopedia of Life project launched yesterday. It gained so much attention, that the site quickly crashed. It went back online Tuesday afternoon (EST), but went down again the next morning.
During five-and-a-half hours, the site logged 11.5 million hits, including visitors who reached the “503 error“.
EOL is estimated to have cost $110.5 million so far.
The site has limited information on 30,000 species, and full profiles of 25 species. These fleshed-out profiles include an article with scientific references, maps of where the species are found, and are illustrated with photos and video. One million placeholder pages have been set up so far, and the plan is to eventually catalog all 1.8 million species.
The Wikimedia Foundation launched a similar project in August 2004, Wikispecies. Perhaps the least known of Wikimedia projects, it “was created to provide an open source forum for taxonomic and biological information.” It has logged 120,247 species, under a free license. The US government runs an Integrated Taxonomic Information System, with 464,081 scientific names. It is created in partnership with similar Canadian and Mexican databases.
There is also a Tree of Life Web Project, and a Catalogue of Life, the latter being the most successful; it is a compilation of 1,008,965 species, from 47 taxonomical databases. ARKive collects media of species, and the All Species Foundation was a failed early attempt at a web catalog.
USA 193, also known as NRO launch 21
22. February 2008 by admin.
USA 193, also known as NRO launch 21 (NROL-21 or simply L-21), was an American military spy satellite launched on December 14, 2006.[2] This was the first launch conducted under contract to the United Launch Alliance.[3] Owned by the National Reconnaissance Office, the craft’s precise function and purpose was classified.
The satellite malfunctioned shortly after deployment, and was intentionally destroyed just over one year later on February 21, 2008 by an SM-3 missile fired from the warship USS Lake Erie, stationed west of Hawaii.[4][5] The event sparked some controversy, being considered part of a wider Space Race involving the U.S., China and Russia.[6]
Launch data
Malfunction and orbital decay
Although launch and insertion into orbit were successful, the satellite lost contact with the ground within hours.[1]
In late January 2008, reports from anonymous U.S. officials indicated a U.S. spy satellite, later confirmed as USA 193,[1] was in a deteriorating orbit and was expected to crash onto Earth within weeks.[13][14] This came as no surprise to amateur satellite watchers, who had been predicting the deorbit of the satellite for some time.[15]
Hazardous materials on-board
Federal Emergency Management Agency (FEMA) reports indicated that the satellite contained the hazardous materials hydrazine and beryllium.[16] Though there was some speculation that the satellite might have a “nuclear” power core,[17] i.e. a radioisotope thermoelectric generator, the FEMA report indicates otherwise.
On January 29, 2008 an Associated Press story quoted a U.S. Air Force general as saying that contingency plans were being made since intact pieces of the satellite “might re-enter into the North American area”.[18]
The United States vowed to pay for any damage or destruction caused by their failed satellite.
Planning for the destruction of USA 193 with a missile reportedly began on January 4, 2008, with President Bush approving the plan on February 12.[20][21] The task force had as its goal to “rupture the fuel tank to dissipate the approximately 1,000 pounds (453 kg) of hydrazine, a hazardous fuel which could pose a danger to people on Earth, before it entered into Earth’s atmosphere”.[22]
On February 14, 2008, U.S. officials announced the plan to destroy USA 193 before atmospheric reentry, stating that the intention was “saving or reducing injury to human life”. They said that if the hydrazine tank fell to Earth it “could spread a toxic cloud roughly the size of two football fields”.[23] General James Cartwright confirmed that the United States Navy was preparing to launch an SM-3 missile to destroy the satellite, at an altitude of 130 nautical miles (240 km), shortly before it entered Earth’s atmosphere.[1]
Explosion of USA 193 following interception by the SM-3 missile.
At 21 February 03:26 GMT the missile launch went ahead. An SM-3 missile was fired from the Ticonderoga-class guided missile cruiser USS Lake Erie, and at an altitude of about 133 nautical miles (247 kilometers)[22] above the Pacific Ocean hit the satellite which was travelling with a velocity of about 17,500 mph (around 28,000 km/h); not the widely reported 22,000 mph calculated by adding the missile’s velocity to that of the satellite. The Department of Defense said it has a “high degree of confidence” that the fuel tank was hit and destroyed,[24] but has not yet confirmed it.[25][26] The satellite’s remnants were expected to burn up over the course of the next forty days, with most of the satellite’s mass re-entering the atmosphere within the first 24 to 48 hours after the missile strike.[22][27]
Controversies
The cost of the destruction operation has been estimated at between $40 million and $60 million.[20] U.S. officials denied that the action was intended to prevent sensitive technology falling into foreign hands,[1] and also denied that it was a response to the 2007 Chinese anti-satellite missile test.[28]
Although the U.S. had objected strongly to the earlier Chinese test of an anti-satellite (or ASAT) weapon that created a large amount of space debris, U.S. officials said there was “no parallel” with that test, as USA 193 was in a much lower orbit, and debris from its destruction would deorbit much sooner, probably within weeks.[1][29]
However, the Russian defense ministry accused the U.S. of using the hydrazine worries as a cover for a test of an ASAT, and noted that extraordinary measures had never before been needed to deal with the many spacecraft that had fallen to Earth.[29] The New York Times had paraphrased Gordon Johndroe, spokesman for the United States National Security Council, as stating that 328 objects had deorbited (controlled and uncontrolled) in the previous 5-year period.[30] U.S. officials maintained that the large quantity of hydrazine on board made USA 193 a special case.[1]
In 1978 the potential dangers of hazardous materials falling to Earth were demonstrated when Cosmos 954, a nuclear-powered Soviet satellite, deorbited and caused environmental damage in Canada.
ALH 84001
17. February 2008 by admin.
This rock is theorized to be one of the oldest pieces of the solar system, proposed to have crystallized from molten rock 4.5 billion years ago. Based on hypotheses surrounding attempts to identify where extraterrestrial rocks come from, it is supposed to have originated on Mars and is related to other martian meteorites. The theory holds that it was shocked and broken by one or more meteorite impacts on the surface of Mars some 3.9 to 4.0 billion years ago, but remained on the planet. It was later blasted off from the surface in a separate impact about 15 million years ago and, following some interplanetary travel, impacted Earth roughly 13,000 years ago. These dates were established by a variety of radiometric dating techniques, including samarium-neodymium (Sm-Nd), rubidium-strontium (Rb-Sr), potassium-argon (K-Ar), and carbon-14.[1][2]
Possible lifeforms
On August 6, 1996[3] ALH 84001 became newsworthy when it was announced that the meteorite contained evidence for traces of life from Mars, as published in an article in Science by Dr. David McKay of NASA.[4][5]
The electron microscope revealed chain structures in meteorite fragment ALH84001Under the scanning electron microscope structures were revealed that may be the remains—in the form of fossils—of bacteria-like lifeforms. The structures found on ALH 84001 are 20-100 nanometres in diameter, similar in size to the theoretical nanobacteria, but smaller than any known cellular life at the time of their discovery. If the structures are really fossilized lifeforms, they would be the first solid evidence of the existence of extraterrestrial life, aside from the chance of their origin being terrestrial contamination.[6]
The announcement of possible extraterrestrial life caused considerable controversy at the time and opened up interest in Martian exploration. When the discovery was announced, many immediately conjectured that the fossils were the first true evidence of extraterrestrial life—making headlines around the world, and even prompting U.S. President Bill Clinton to make a formal televised announcement to mark the event.[7]
Several tests for organic material have been performed on the meteorite and amino acids and polycyclic aromatic hydrocarbons (PAH) have been found. The debate if the organic molecules were created by nonbiological processes or are due to contamination from the contact with Antarctic ice is still ongoing.[8][9]
As of 2006, some experts still argue that the microfossils are not indicative of life, but instead are caused by contamination by earthly biofilms. It has not yet conclusively been shown how the features were formed, but similar features have been recreated in labs without biological inputs.[3] Nevertheless, evidence continues to grow that nanobacteria do exist, in spite of initial skepticism[citation needed] (based on the idea that the particles were too small to contain RNA).
Recent studies on ALH 84001 have shown that, although chances are low, eventually, Martian rocks such as ALH 84001 could actually transfer Martian life to Earth[1]. Around 1 in 10 million meteorites from Mars arrives in less than a year, and around 10 rocks that weigh more than 100 grams make the journey in 2-3 years. Bacterial spores, and rock dwelling organisms are speculated to survive in space for 5 years, meaning transfer of Martian life to our planet is theoretically possible.
If Mars’s atmosphere at the time life started on Earth was like it is now, though, survival and propagation of any life form after arriving would be even less likely. The life form’s native environment probably would be completely unlike anywhere it would land on Earth. Mars has an atmosphere many times thinner than that on top of Mount Everest, with almost no water. A life form evolved to survive in such conditions would almost invariably find dense air to be toxic, as it would the relatively high temperatures[citation needed]: even the Antarctic does not get as cold as much of Mars does much of the year. However, it is hypothesized that ALH 84001 originated from a time period during which water may have existed on Mars.[3] Also, Earth’s atmosphere at that time was largely anoxic, i.e., without oxygen. Other meteorites that have potential biological markings have generated less interest because they do not originate from a “wet” Mars. ALH 84001 is the only meteorite collected from such a time period.
Origin on Mars
In September 2005, Vicky Hamilton of the University of Hawaii at Manoa presented an analysis of the origin of ALH 84001 using data from the Mars Global Surveyor and Mars Odyssey spacecraft orbiting Mars. According to the analysis, Eos Chasma in the Valles Marineris canyon appears to be the source of the meteorite.[10] The analysis was not conclusive, in part because it was limited to parts of Mars not obscured by dust.
