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World's oldest DNA sequenced from million-year-old mammoths – CTV News

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Teeth from mammoths buried in the Siberian permafrost for more than a million years have yielded the world’s oldest DNA ever sequenced, according to a study published on Wednesday, shining the genetic searchlight into the deep past. 

Researchers said the three specimens, one roughly 800,000 years old and two over a million years old, provide important insights into the giant Ice Age mammals, including the ancient heritage of the woolly mammoth.    

The genomes far exceed the oldest previously sequenced DNA — a horse dating between 780,000 to 560,000 years ago.

“This DNA is incredibly old. The samples are a thousand times older than Viking remains, and even pre-date the existence of humans and Neanderthals,” said Love Dalen, a professor of evolutionary genetics at the Centre for Palaeogenetics in Stockholm, senior author of the study published in Nature.

The mammoths were originally discovered in the 1970s in Siberia and held at the Russian Academy of Sciences in Moscow. 

Researchers first dated the specimens geologically, with comparisons to other species, like small rodents, known to be unique to particular time periods and found in the same sedimentary layers. 

This suggested that two of the mammals were ancient steppe mammoths more than a million years old.

The youngest of the trio is one of the earliest woolly mammoths yet found.

DNA JIGSAW

They also extracted genetic data from tiny samples of powder from each mammoth tooth, “essentially like a pinch of salt you would put on your dinner plate,” Dalen told a press briefing. 

While it had degraded into very small fragments, scientists were able to sequence tens of millions of chemical base pairs, which make up the strands of DNA, and conduct age estimates from genetic information.

This suggested that the oldest mammoth, named Krestovka, is even older at approximately 1.65 million years old, while the second, Adycha, is around 1.34 million years old, and the youngest Chukochya is 870,000 years old.

Dalen said the discrepancy for the oldest mammoth could be an underestimation in the DNA dating process, meaning the creature was likely around 1.2 million years old, as suggested by the geological evidence. 

But he said it was possible the specimen was indeed older and had thawed out of the permafrost at one point and then become wedged in a younger layer of sediment.

The DNA fragments were like a puzzle with millions of tiny pieces, “way, way, way smaller than you would get from modern high quality DNA”, said lead author Tom van der Valk, of the Science for Life Laboratory, Uppsala University.

Using a genome from an African elephant, a modern relative of the mammoth, as a blueprint for their algorithm, researchers were able to reconstruct parts of the mammoth genomes.

The study found that the older Krestovka mammoth represents a previously unrecognised genetic lineage, which researchers estimated diverged from other mammoths around two million years ago and was ancestral to those that colonised North America.

The study also traced the lineage from the million-year-old Adycha steppe mammoth to Chukochya and other more recent woolly mammoths. 

It found gene variants associated with life in the Arctic, like hairiness, thermoregulation, fat deposits and cold tolerance in the older specimen, suggesting mammoths were already hairy long before the woolly mammoth emerged.

Siberia has alternated between dry and cold Ice Age conditions and warm, wet periods.

Now climate change is melting the permafrost and revealing more specimens, Dalen said, although higher rainfall could mean remains are washed away.

He said new technologies mean it may be possible to sequence even older DNA from remains found in the permafrost, which dates back 2.6 million years.

Researchers are keen to look at creatures such as the ancestors of moose, muskox, wolves, and lemmings, to shine a light on the evolution of modern species. 

“Genomics has been pushed into deep time by the giants of the Ice Age,” said Alfred Roca, a professor in the Department of Animal Sciences at the University of Illinois, in a comment piece published in Nature. 

“The wee mammals that surrounded them might soon also have their day.”

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SpaceX launches 60 new Starlink satellites, while Starship moves closer to being able to launch up to 400 at a time – Yahoo Movies Canada

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SpaceX has launched another batch of its Starlink satellites – the usual complement of 60 of the low Earth orbit spacecraft, which will join the more than 1,000 already making up the existing constellation. This is the fifth launch of Starlink satellites for SpaceX this year, and the 20th overall.

Earlier this year, SpaceX opened up Starlink access to anyone in a current or planned service area via a pre-order reservation system with a refundable up-front deposit. The company aims to continue launches like this one apace throughout 2021 in order to get the constellation to the point where it can serve customers over a much larger portion of the globe. SpaceX COO and President Gwynne Shotwell has previously said that the company expects it should have coverage over much of the globe at a constellation size of around 1,200 satellites, but the company has plans to launch more than 30,000 to fully build out its network capacity and speed.

While SpaceX is making good progress on Starlink with its Falcon 9 launcher, it’s also looking ahead to Starship as a key driver of the constellation’s growth. Starship, SpaceX’s next-generation launch vehicle currently under development in South Texas, will be able to deliver 400 Starlink satellites at a time to orbit, and it’s also being designed with full reusability and fast turnaround in mind.

The ability to launch more than six times as many satellites per mission would help SpaceX a lot in terms of the speed with which they can deploy the Starlink network, as well as the overall cost of the endeavor – assuming their cost projections about Starlink’s general affordability are even close to accurate once it becomes a high-volume production rocket. That’s definitely still at least a few years off, but SpaceX did mark a milestone on Wednesday that bodes well for its chances of making that happen.

The company’s latest Starship prototype performed its most successful test launch to date on Wednesday, taking off from SpaceX’s Boca Chica, Texas development site and flying to around 32,000 feet before executing a ‘flop’ maneuver and then reorienting itself for a soft vertical landing. The test rocket also blew up after sitting on the pad for just under 10 minutes, but despite that spectacular ending, the test proved out a lot of the basic engineering work that SpaceX needs to make Starship a reality.

Starlink is a huge, multi-year effort, so even if Starship is still a few years away from high-volume production and flight, it should still have a significant impact on the project overall. And Starlink, once operational and fully deployed, will require regular maintenance – individual satellites in the network are only really designed to be operational for ups to five years max, with regular replacements required to keep things running smoothly.

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SpaceX sticks 75th Falcon rocket landing after launching 60 more Starlink satellites – Spaceflight Now – Spaceflight Now

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A Falcon 9 rocket disappears in a blanket of clouds shortly after launching from NASA’s Kennedy Space Center early Thursday. Credit: SpaceX

Launching through a blanket of low-hanging clouds and light mist, a SpaceX Falcon 9 rocket thundered into the sky over Florida’s Space Coast early Thursday and delivered 60 more Starlink internet satellites to orbit. The rocket’s first stage touched down on SpaceX’s floating landing platform in the Atlantic Ocean to complete its eighth trip to space and back.

The 229-foot-tall (70-meter) Falcon 9 rocket flashed to life and lifted off from pad 39A at the Kennedy Space Center at 3:24:54 a.m. EST (0824:54 GMT). Fifteen seconds later, the liquid-fueled launcher disappeared into a cloud deck over the seaside spaceport, leaving behind an orange flow that slowly faded with the roar of the Falcon 9’s powerful main engines.

Arcing toward the northeast, the Falcon 9 exceeded the speed of sound and dropped its first stage booster about two-and-a-half minutes after liftoff. A single Merlin engine on the upper stage ignited to continue the flight into space, while the first stage descended to a propulsive landing on the drone ship “Of Course I Still Love You” positioned about 400 miles (630 kilometers) downrange from Cape Canaveral.

The successful landing marked the 75th intact recovery of a Falcon rocket booster since December 2015. The booster on Thursday mission — designated B1049 — made its eighth launch and landing after debuting in September 2018, tying another first stage for the most number of flights in SpaceX’s fleet.

A Falcon 9 booster on SpaceX’s previous launch Feb. 15 failed to land on the drone ship after one of its nine main engines shut down prematurely during ascent.

After reaching a preliminary parking orbit, the upper stage coasted halfway around the world before firing its engine again for a one-second orbit adjustment burn over the Indian Ocean. The 60 Starlink satellites deployed from the Falcon 9’s upper stage at 4:29 a.m. EST (0929 GMT) while flying 172 miles (278 kilometers) above Earth just south of New Zealand.

The on-target launch came after a series of delays kept the mission grounded since late January. The delays were caused by weather and unspecified technical issues, and two other Falcon 9 missions with Starlink satellites took off from nearby pad 40 at Cape Canaveral Space Force Station while the flight from pad 39A stayed earthbound.

The change in the order of missions meant the batch launched Thursday was on the 20th Falcon 9 flight dedicated to carrying Starlink satellites, despite its designation on the military-run Eastern Range as Starlink V1.0-L17. Launches No. 18 and 19 ended up flying before No. 17.

The 60 Starlink satellites, each weighing about a quarter-ton, will unfurl their solar panels and switch on ion krypton thrusters to begin raising their altitude to 341 miles (550 kilometers) in the coming weeks. At that altitude, the satellites will join more than 1,000 active Starlink satellites flying in orbits inclined 53 degrees to the equator, taking them above nearly all of the world’s populated regions.

SpaceX has launched 1,205 Starlink satellites to date with the 60 fresh relay stations delivered to orbit Thursday. But 63 of the Starlinks have been intentionally deorbited or re-entered the atmosphere after failing, and another 20 are not maneuvering or appear to be in the process of deorbiting, according to a tally of Starlink satellites from Jonathan McDowell, an astronomer and respected tracker of spaceflight activity.

SpaceX is well on the way to finish deployment of its initial tranche of 1,584 Starlink stations — including spares — later this year. SpaceX won’t stop there, with plans to launch additional orbital “shells” of Starlink satellites into polar orbit to enable global coverage, with a first-generation fleet totaling some 4,400 spacecraft.

The Federal Communications Commission has authorized SpaceX to eventually operate up to 12,000 Starlink satellites.

The company is already providing an interim level of service over parts of the Earth, such as Canada, northern parts of the United States, and the United Kingdom. Beta testing of the Starlink services is already underway with users in those regions. SpaceX is also accepting pre-orders from Starlink consumers, who can pay $99 to reserve their place in line to get Starlink service when it becomes available in their area. For people in the southern United States and other lower-latitude regions, that should come by late 2021, SpaceX says.

Once confirmed, customers will pay $499 for a Starlink antenna and modem, plus $50 in shipping and handling, SpaceX says. A subscription will run $99 per month.

A SpaceX Falcon 9 booster stands on the drone ship “Of Course I Still Love You” after launch Thursday. Credit: SpaceX

“Starlink continues to improve as SpaceX deploys additional infrastructure and capability, averaging two Starlink launches per month, to add significant on-orbit capacity alongside activation of additional gateways to improve performance and expand service coverage areas across the country,” SpaceX wrote in the filing.

Elon Musk, SpaceX’s founder and CEO, tweeted Feb. 9 that SpaceX’s Starlink subsidiary will go public once it has a predictable cash flow.

“Once we can predict cash flow reasonably well, Starlink will IPO,” Musk tweeted.

Until then, SpaceX will be spending cash at a high rate to maintain the Starlink network’s high-tempo deployment, from satellite launches at an average pace of every couple of weeks to the manufacturing of user ground terminals. SpaceX has said the entire project could cost more than $10 billion, but Musk has said the revenue opportunities are even higher, providing resources for SpaceX to advance its audacious plans to send people to Mars.

The centerpiece of SpaceX’s Mars plans is a next-generation fully reusable rocket called the Starship, which the company says will eventually replace the company’s Falcon 9 rocket and Dragon spacecraft.

The Falcon 9 launch early Thursday occurred less than a half-day after at atmospheric test flight of a Starship prototype from SpaceX’s development facility in South Texas. The Starship test vehicle made a controlled landing, a first for a Starship descending from high altitude, and a major step forward for the rocket program.

But the prototype exploded a few minutes later, scattering debris across the landing site on Texas Gulf Coast. Nevertheless, SpaceX declared the test a success.

SpaceX’s jam-packed launch schedule continues with the next Falcon 9 mission set to blast off Sunday night from pad 40 at Cape Canaveral Space Force Station with 60 more Starlink satellites. That flight is scheduled for 10:41 p.m. EST Sunday (0341 GMT Monday), followed by more Falcon 9 launches with Starlink satellites in the coming weeks.

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Follow Stephen Clark on Twitter: @StephenClark1.

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NASA's Perseverance Mars rover deploys wind sensor as health checks continue – Firstpost

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A fortnight since its widely-documented touch down on Mars, NASA’s Perseverance rover continues to find its bearings and stretch its numerous ‘arms’ on the Red Planet. Since the 18 February landing, the rover team has been performing a methodical battery of tests on its seven science instruments, and begun deploying the ones that work. In the latest deployment, Perseverance deployed its wind sensor, as seen in photographs captured by the navigation cameras on board.

The Perseverance rover’s navigation cameras show the wind sensor deployed. Image Credit: NASA/JPL-Caltech

The wind sensor is one of the instruments part of a weather monitoring experiment on the rover called the Mars Environmental Dynamics Analyzer (MEDA). The sensor collects data on air temperature, humidity, radiation, dust and wind around the rover, which is currently parked in its landing site – the Jezero Crater, a 45-km-wide depression in the ground that is thought to have once been home to an ancient lake and river delta.

The High Resolution Imaging Experiment (HiRISE) on NASA’s Mars Reconnaissance Orbiter, spotted Perseverance at its landing site, six days after touchdown and in the process of system checks.

Perseverance rover and the Jezero Crater around it, as seen by HiRISE on 24 February. Image Credit: HiRISE: Beautiful Mars/Twitter

Perseverance rover and the Jezero Crater around it, as seen by HiRISE on 24 February. Image Credit: HiRISE: Beautiful Mars/Twitter

From the orbiter’s vantage point over 250 kilometres away in orbit, the ground below Percy’s wheels appears to be loose, dark material, with brighter material underneath. The bright zones are visible on either side of the rover, likely “scoured clear by the descent stage rockets” during descent, as per a statement on the HiRISE website.

In late February, ESA’s Trace Gas Orbiter shared another wide view of the rover and components after its descent, littering the surface of the Red Planet. The Perseverance rover is visible in images as a relatively faint spot next to a ridge connecting to one of the smaller craters in the vicinity.

Ingenuity: Perseverance rover’s first ‘big job’

Perseverance’s first big job will be to find an airfield where its little helicopter buddy can take off, according to a Space.com report. Mission controllers received the first status report from the Ingenuity Mars Helicopter attached to the belly of the rover, hours after its landing. Ingenuity will remain attached to the rover for the next several weeks, NASA had said in a statement at the time. Provided Ingenuity survives the frigid Martian nights to come, where temperatures dip to lows of minus 90 degrees Celsius, the mission team will proceed with the first flight of an aircraft on another world.

If Ingenuity manages to land successfully and remain operable, NASA may send four successors, “each building on the success of the last”, the agency said. These descendants of the Ingenuity rotorcraft can bring an aerial dimension to exploration of Mars.

Also read: ESA’s Trace Gas Orbiter, NASA’s HiRISE catch stunning glimpses of Perseverance rover on Mars

NASA shares video, audio of Perseverance Mars landing

Ingenuity helicopter reports in

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