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Mile-Wide ‘Planet Killer’ Asteroid Found In Sun’s Glare, Say Scientists

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An asteroid reckoned to be a mile/1.5 kilometers wide has been found in the Sun’s glare—and it has an orbit that may someday place it in Earth’s path.

Its size makes it big enough to be called a “planet killer.”

Asteroid 2022 AP7 is the largest “potentially hazardous” object to be discovered in the last eight years. It was found by astronomers using a telescope in Chile to study the region near the glare of the Sun.

This near-Earth asteroid is part of an elusive population that lurks inside the orbits of Earth and Venus, which are notoriously difficult to find. While most asteroid-hunting telescopes spend the night looking at the outer solar system, studying the inner solar system requires observations only in the 10 minutes of twilight both after sunset and before sunrise.

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2022 AP7 is only one of three new near-Earth asteroids (NEAs) uncovered in the inner Solar System—the region interior to the orbits of Earth and Venus—in a new paper published today in The Astronomical Journal.

The other two asteroids discovered, called 2021 LJ4 and 2021 PH27, have orbits interior to Earth’s orbit, so are no threat. 2021 PH27 is the closest known asteroid to the Sun.

2022 AP7 isn’t the only “planet killer” asteroid found by the survey. “Our twilight survey is scouring the area within the orbits of Earth and Venus for asteroids,” said Scott S. Sheppard, an astronomer at the Earth and Planets Laboratory of the Carnegie Institution for Science and the lead author. “So far we have found two large near-Earth asteroids that are about 1 kilometer across, a size that we call planet-killers.”

As well as only having two brief 10-minute windows each night to survey the area of the Sun’s glare the astronomers have to look very close to the horizon, which means looking through the thickest part of Earth’s atmosphere. That can blur and distort their data. “Large areas of sky are required because the inner asteroids are rare, and deep images are needed because asteroids are faint and you are fighting the bright twilight sky near the Sun as well as the distorting effect of Earth’s atmosphere,” said Sheppard.

Only about 25 asteroids with orbits completely within Earth’s orbit have been discovered to date because of the difficulty of observing near the glare of the Sun.

However, the search continues because the survey is tantalisingly close to completion. “There are likely only a few near-Earth asteroids with similar sizes left to find, and these large undiscovered asteroids likely have orbits that keep them interior to the orbits of Earth and Venus most of the time,” said Sheppard.

The observations were made using the US Department of Energy-fabricated Dark Energy Camera (DECam) on the Víctor M. Blanco 4-meter Telescope at NOIRLab’s Cerro Tololo Inter-American Observatory in Chile. “DECam can cover large areas of sky to depths not achievable on smaller telescopes, allowing us to go deeper, cover more sky, and probe the inner Solar System in ways never done before,” said Sheppard.

Wishing you clear skies and wide eyes.

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Discovery Of World's Oldest DNA Breaks Record By One Million Years – Forbes

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Microscopic fragments of DNA were found in Ice Age sediment in northern Greenland. Using cutting-edge technology, researchers discovered the fragments are one million years older than the previous record for DNA sampled from a Siberian mammoth bone.

The discovery was made by a team of scientists led by Professor Eske Willerslev and Professor Kurt H. Kjær. Professor Willerslev is a Fellow of St John’s College, University of Cambridge, and Director of the Lundbeck Foundation GeoGenetics Center at the University of Copenhagen where Professor Kjær, a geology expert, is also based.

“A new chapter spanning one million extra years of history has finally been opened and for the first time we can look directly at the DNA of a past ecosystem that far back in time,” so Professor Willerslev commenting the discovery.

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“DNA can degrade quickly but we’ve shown that under the right circumstances, we can now go back further in time than anyone could have dared imagine.”

Professor Kjær adds that “the ancient DNA samples were found buried deep in sediment that had built-up over 20,000 years. The sediment was eventually preserved in ice or permafrost and, crucially, not disturbed by humans for two million years.”

The incomplete samples, a few millionths of a millimeter long DNA strings, were taken from the København Formation, a sediment formation almost 100 meters thick deposited in the shallow area of a fjord in Greenland’s northernmost point. The climate in Greenland at the time of sedimentation was between 10 to 17 degrees warmer than today, sustaining an ecosystem with no present-day equivalent, resembling a mix of temperate forest and mixed-grass prairie.

Detective work by 40 researchers from Denmark, the UK, France, Sweden, Norway, the U.S. and Germany, unlocked the secrets of the fragments of DNA. The process was painstaking – first they needed to establish whether there was DNA hidden in the sediment, and if there was, could they successfully detach the DNA from the mineral grains – like clay particles and quartz crystals – to examine it? The answer, eventually, was yes. The researchers compared every single DNA fragment with extensive libraries of DNA collected from present-day animals, plants and microorganisms.

The scientists discovered evidence of animals, plants and microorganisms including reindeer, hares, lemmings, birch and poplar trees. They even found that Mastodon, an Ice Age elephant, roamed as far as Greenland before later becoming extinct. Previously it was thought the range of the species did not extend from its known origins of North and Central America.

Some of the DNA fragments were easy to classify as predecessors to present-day species, others could only be linked at genus level, and some originated from species impossible to place in the DNA libraries of animals, plants and microorganisms still living today.

The findings have opened up a whole new period in DNA detection. Thanks to a new generation of extraction and sequencing equipment, researchers will be able to locate and identify extremely small and damaged fragments of genetic information in sediments considered previously unfit for DNA preservation.

“DNA generally survives best in cold, dry conditions such as those that prevailed during most of the period since the material was deposited at Kap København. Now that we have successfully extracted ancient DNA from clay and quartz, it may be possible that clay may have preserved ancient DNA in warm, humid environments in sites found in Africa,” Professor Willerslev concludes.

The paper “A 2-million-year-old ecosystem in Greenland uncovered by environmental DNA” is published in Nature. Material provided by the by University of Cambridge.

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NASA posts high-resolution images of Orion’s final lunar flyby

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Orion just made its final pass around the moon on its way to Earth, and NASA has released some of the spacecraft’s best photos so far. Taken by a high-resolution camera (actually a heavily modified GoPro Hero 4) mounted on the tip of Orion’s solar arrays, they show the spacecraft rounding the Moon then getting a closeup shot of the far side.

The photos Orion snapped on its first near pass to the Moon were rather grainy and blown out, likely because they were captured with Orion’s Optical Navigation Camera rather than the solar array-mounted GoPros. Other GoPro shots were a touch overexposed, but NASA appears to have nailed the settings with its latest series of shots.

Space photos were obviously not the primary goal of the Artemis I mission, but they’re important for public relations, as NASA learned many moons ago. It was a bit surprising that NASA didn’t show some high-resolution closeups of the Moon’s surface when it passed by the first time, but better late than never.

Orion’s performance so far has been “outstanding,” program manager Howard Hu told reporters last week. It launched on November 15th as part of the Artemis 1 mission atop NASA’s mighty Space Launch System. Days ago, the craft completed a three and a half minute engine burn (the longest on the trip so far) to set it on course for a splashdown on December 11th.

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The next mission, Artemis II, is scheduled in 2024 to carry astronauts on a similar path to Artemis I without landing on the moon. Then, humans will finally set foot on the lunar surface again with Artemis III, slated for launch in 2025.

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Biosignatures: Discovery Of Earth’s Oldest DNA Breaks Record By One Million Years

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Taxonomic profiles of the plant assemblage found in the metagenomes. Taxa in bold are genera only found as DNA and not as macrofossil or pollen. Asterisks indicate those that are found at other Pliocene Arctic sites. Extinct species as identified by either macrofossils or phylogenetic placements are marked with a dagger. Reads classified as Pyrus and Malus are marked with a pound symbol, and are probably over-classified DNA sequences belonging to another species within Rosaceae that are not present as a reference genome. — University of Cambridge

Two-million-year-old DNA has been identified for the first time – opening a ‘game-changing’ new chapter in the history of evolution.

 

Microscopic fragments of environmental DNA were found in Ice Age sediment in northern Greenland. Using cutting-edge technology, researchers discovered the fragments are one million years older than the previous record for DNA sampled from a Siberian mammoth bone.

The ancient DNA has been used to map a two-million-year-old ecosystem which weathered extreme climate change. Researchers hope the results could help to predict the long-term environmental toll of today’s global warming.

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The discovery was made by a team of scientists led by Professor Eske Willerslev and Professor Kurt H. Kjær. Professor Willerslev is a Fellow of St John’s College, University of Cambridge, and Director of the Lundbeck Foundation GeoGenetics Centre at the University of Copenhagen where Professor Kjær, a geology expert, is also based.

The results of the 41 usable samples found hidden in clay and quartz are published today (7 DECEMBER 2022) in Nature.

Professor Willerslev said: “A new chapter spanning one million extra years of history has finally been opened and for the first time we can look directly at the DNA of a past ecosystem that far back in time..

“DNA can degrade quickly but we’ve shown that under the right circumstances, we can now go back further in time than anyone could have dared imagine.”

Professor Kjær said: “The ancient DNA samples were found buried deep in sediment that had built-up over 20,000 years. The sediment was eventually preserved in ice or permafrost and, crucially, not disturbed by humans for two million years.”

The incomplete samples, a few millionths of a millimetre long, were taken from the København Formation, a sediment deposit almost 100 metres thick tucked in the mouth of a fjord in the Arctic Ocean in Greenland’s northernmost point. The climate in Greenland at the time varied between Arctic and temperate and was between 10-17C warmer than Greenland is today. The sediment built up metre by metre in a shallow bay.

Scientists discovered evidence of animals, plants and microorganisms including reindeer, hares, lemmings, birch and poplar trees. Researchers even found that Mastodon, an Ice Age mammal, roamed as far as Greenland before later becoming extinct. Previously it was thought the range of the elephant-like animals did not extend as far as Greenland from its known origins of North and Central America.

Detective work by 40 researchers from Denmark, the UK, France, Sweden, Norway, the USA and Germany, unlocked the secrets of the fragments of DNA. The process was painstaking – first they needed to establish whether there was DNA hidden in the clay and quartz, and if there was, could they successfully detach the DNA from the sediment to examine it? The answer, eventually, was yes. The researchers compared every single DNA fragment with extensive libraries of DNA collected from present-day animals, plants and microorganisms. A picture began to emerge of the DNA from trees, bushes, birds, animals and microorganisms.

Some of the DNA fragments were easy to classify as predecessors to present-day species, others could only be linked at genus level, and some originated from species impossible to place in the DNA libraries of animals, plants and microorganisms still living in the 21st century.

The two-million-year-old samples also help academics build a picture of a previously unknown stage in the evolution of the DNA of a range of species still in existence today.

Professor Kjær said: “Expeditions are expensive and many of the samples were taken back in 2006 when the team were in Greenland for another project, they have been stored ever since.

“It wasn’t until a new generation of DNA extraction and sequencing equipment was developed that we’ve been able to locate and identify extremely small and damaged fragments of DNA in the sediment samples. It meant we were finally able to map a two-million-year-old ecosystem.”

Assistant Professor Mikkel W. Pedersen, co-first author on the paper and also based at the Lundbeck Foundation GeoGenetics Centre, said: “The Kap København ecosystem, which has no present-day equivalent, existed at considerably higher temperatures than we have today – and because, on the face of it, the climate seems to have been similar to the climate we expect on our planet in the future due to global warming.

“One of the key factors here is to what degree species will be able to adapt to the change in conditions arising from a significant increase in temperature. The data suggests that more species can evolve and adapt to wildly varying temperatures than previously thought. But, crucially, these results show they need time to do this. The speed of today’s global warming means organisms and species do not have that time so the climate emergency remains a huge threat to biodiversity and the world – extinction is on the horizon for some species including plants and trees.”

While reviewing the ancient DNA from the Kap København Formation, the researchers also found DNA from a wide range of microorganisms, including bacteria and fungi, which they are continuing to map. A detailed description of how the interaction – between animals, plants and single-cell organisms – within the former ecosystem at Greenland’s northernmost point worked biologically will be presented in a future research paper.

It is now hoped that some of the ‘tricks’ of the two-million-year-old plant DNA discovered may be used to help make some endangered species more resistant to a warming climate.

Professor Kjær said: “It is possible that genetic engineering could mimic the strategy developed by plants and trees two million years ago to survive in a climate characterised by rising temperatures and prevent the extinction of some species, plants and trees. This is one of the reasons this scientific advance is so significant because it could reveal how to attempt to counteract the devastating impact of global warming.”

The findings from the Kap København Formation in Greenland have opened up a whole new period in DNA detection.

Professor Willerslev explained: “DNA generally survives best in cold, dry conditions such as those that prevailed during most of the period since the material was deposited at Kap København. Now that we have successfully extracted ancient DNA from clay and quartz, it may be possible that clay may have preserved ancient DNA in warm, humid environments in sites found in Africa.

“If we can begin to explore ancient DNA in clay grains from Africa, we may be able to gather ground-breaking information about the origin of many different species – perhaps even new knowledge about the first humans and their ancestors – the possibilities are endless.”

 

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