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After Arecibo, NASA isn't sure what comes next for planetary radar – Space.com

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Arecibo Observatory’s massive radio telescope has collapsed; with it has gone a crucial tool in understanding asteroid risks to Earth — and it would take a serious government initiative to replace.

Before the facility sustained irreversible damage in a series of cable failures this year, Arecibo Observatory was Earth’s most powerful planetary radar system. Astronomers can’t use radar to discover new asteroids, but the data that these systems provide can give scientists the details about an object’s size, shape and location they need to better and more quickly evaluate the threat that individual asteroids might pose to Earth. 

“This is a hard thing to have to take [down] an iconic facility like this that’s provided so much for the radio astronomy and planetary radar community over so many decades; it’s really sad to see,” Lindley Johnson, who leads NASA’s Planetary Defense Coordination Office, said during a virtual meeting of NASA’s Planetary Advisory Committee held on Nov. 30, the day before the structure collapsed. “It’s certainly not an ideal situation, but I think it really comes down to, it’s time to really get moving on investing in a new planetary radar capability.”

Related: Losing Arecibo’s giant dish leaves humans more vulnerable to space rocks, scientists say

But that’s easier said than done. There are two key complications at play when it comes to investing in planetary radar capability.

One is bureaucratic: Planetary radar has to be done from Earth’s surface. And while NASA leads the country’s asteroid-focused work, the U.S. National Science Foundation (NSF) heads the federal government’s ground-based observations, as it does Arecibo Observatory; NASA merely paid for observation time on the radar system. With the sole exception of NASA’s Infrared Telescope Facility in Hawaii, all of the agency’s observing facilities are in space.

(This is also complicated. Technically, the world’s other planetary radar facility, at Goldstone in California, is run by NASA, but that’s because its primary duty is to communicate with spacecraft traversing the solar system. The radar facility recently completed an upgrade and is back to normal observations, although it has a less flexible schedule than Arecibo did and can’t see objects as far from Earth.)

Related: Losing Arecibo Observatory would create a hole that can’t be filled, scientists say 

“The way our agencies are tasked, ground-based observations are the responsibility of NSF,” Lori Glaze, who leads NASA’s Planetary Science Division, said during the same meeting. “It’s not in NASA’s purview.”

A second complication is the cost. A radar beam as powerful as Arecibo’s requires both a powerful transmitter and a massive radio dish, neither of which is cheap. 

Taken together, the challenges mean that NASA would likely need to work out agreements with one or more government counterparts before a new planetary radar system comes online.

“This kind of thing really takes a partnership of agencies,” Johnson said, adding that Arecibo itself traced its roots to a Department of Defense-led partnership. Something similar could rev up planetary radar, he said. “We do definitely have an opportunity and an interest in partnering with the U.S. Space Force on a more capable radar system.” The military branch is interested in the technology as a way to track satellites between Earth and the moon, he added.

Related: Arecibo isn’t the first radio telescope to unexpectedly fail. Here’s what we can learn from Green Bank’s collapse.

A reduction in planetary radar doesn’t strike at the heart of NASA’s planetary defense system, which focuses on discovering and tracking relatively large asteroids that come relatively close to Earth. Spotting such objects relies on facilities that detect optical and infrared light and scan large swaths of the sky regularly enough to notice when a new, fast-moving dot appears against the background of stars.

Radar can’t do that; it requires that scientists have a good idea of precisely where the object they want to study is, so that they can point the narrow radar beam precisely enough to bounce off the object. Instead, planetary defense experts use radar to more quickly plot an object’s orbit farther into the future and to determine characteristics of the object like its shape and density that might affect attempts to deflect an asteroid if it does appear to be on course to impact Earth.

“As far as planetary defense and NEO [near-Earth object] observations are concerned, it’s only a slight negative impact,” Johnson said of the loss of Arecibo’s radar system. “It doesn’t affect our discovery rate of near-Earth objects at all, it only has some impact on the opportunities we have to characterize these objects.”

Radar data of an asteroid dubbed Phaethon captured by Arecibo Observatory in December 2017. (Image credit: Arecibo Observatory/NASA/NSF)

Nevertheless, radar data is nice to have — and definitely the sort of thing Johnson would want for the planetary defense community.

Green Bank Observatory in West Virginia was already planning to add radar capability to its primary radio dish before the loss of Arecibo, scientists say, although the system, like that at Goldstone, won’t replicate Arecibo’s specific skills. And even that new capability would build on an existing facility, rather than starting from scratch, which comes with both benefits and risks.

“In a perfect world, I would pursue a new planetary radar capability,” Johnson said, even before Arecibo’s final collapse. “Trying to keep these old facilities going — they are high maintenance.”

But new capability wouldn’t mean a copy of Arecibo’s iconic dish, he emphasized. “It’s really time to be looking at the next generation of planetary radar capabilities,” he said, in particular hypothesizing that an array of dishes may be a more appealing approach now than Arecibo’s single massive dish.

“Technology has moved on since the 30, 40 years ago that the radar capability was installed at Arecibo,” Johnson said. “We need to take advantage.”

Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook. 

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New species of crested dinosaur identified in Mexico

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A team of palaeontologists in Mexico have identified a new species of dinosaur after finding its 72 million-year-old fossilized remains almost a decade ago, Mexico’s National Institute of Anthropology and History (INAH) said on Thursday.

The new species, named Tlatolophus galorum, was identified as a crested dinosaur after 80% of its skull was recovered, allowing experts to compare it to other dinosaurs of that type, INAH said.

The investigation, which also included specialists from the National Autonomous University of Mexico, began in 2013 with the discovery of an articulated tail in the north-central Mexican state of Coahuila, where other discoveries have been made.

“Once we recovered the tail, we continued digging below where it was located. The surprise was that we began to find bones such as the femur, the scapula and other elements,” said Alejandro Ramírez, a scientist involved in the discovery.

Later, the scientists were able to collect, clean and analyze other bone fragments from the front part of the dinosaur’s body.

The palaeontologists had in their possession the crest of the dinosaur, which was 1.32 meters long, as well as other parts of the skull: lower and upper jaws, palate and even a part known as the neurocranium, where the brain was housed, INAH said.

The Mexican anthropology body also explained the meaning of the name – Tlatolophus galorum – for the new species of dinosaur.

Tlatolophus is a mixture of two words, putting together a term from the indigenous Mexican language of Nahuatl that means “word” with the Greek term meaning “crest”. Galorum refers to the people linked to the research, INAH said.

 

(Reporting by Abraham Gonzalez; Writing by Drazen Jorgic; Editing by Ana Nicolaci da Costa)

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Alberta family searches for answers in teen's sudden death after COVID exposure, negative tests – CBC.ca

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A southern Alberta mother and father are grappling with the sudden, unexplained death of their 17-year-old daughter, and with few answers, they’re left wondering if she could be the province’s youngest victim of COVID-19.

Sarah Strate — a healthy, active Grade 12 student at Magrath High School who loved singing, dancing and being outdoors — died on Monday, less than a week after being notified she’d been exposed to COVID-19.

While two tests came back negative, her parents say other signs point to the coronavirus, and they’re waiting for more answers. 

“It was so fast. It’s all still such a shock,” said Sarah’s mother, Kristine Strate. “She never even coughed. She had a sore throat and her ears were sore for a while, and [she had] swollen neck glands.”

Kristine said Sarah developed mild symptoms shortly after her older sister — who later tested positive for COVID-19 —  visited from Lethbridge, one of Alberta’s current hot spots for the virus.

The family went into isolation at their home in Magrath on Tuesday, April 20. They were swabbed the next day and the results were negative.

‘Everything went south, super-fast’

By Friday night, Sarah had developed fever and chills. On Saturday, she started vomiting and Kristine, a public health nurse, tried to keep her hydrated.

“She woke up feeling a bit more off on Monday morning,” Kristine said. “And everything went south, super-fast.”

Sarah had grown very weak and her parents decided to call 911 when she appeared to become delirious.

“She had her blanket on and I was talking to her and, in an instant, she was unresponsive,” said Kristine, who immediately started performing CPR on her daughter.

When paramedics arrived 20 minutes later, they were able to restore a heartbeat and rushed Sarah to hospital in Lethbridge, where she died.

“I thought there was hope once we got her heart rate back. I really did,” recalled Sarah’s father, Ron.

“He was praying for a miracle, and sometimes miracles don’t come,” said Kristine.

Strate’s parents say her health deteriorated quickly after being exposed to COVID-19. She died at Chinook Regional Hospital in Lethbridge on Monday. (Ron Strate)

Searching for answers

At the hospital, the family was told Sarah’s lungs were severely infected and that she may have ended up with blood clots in both her heart and lungs, a condition that can be a complication of COVID-19.

But a second test at the hospital came back negative for COVID-19.

“There really is no other answer,” Ron said. “When a healthy 17-year-old girl, who was sitting up in her bed and was able to talk, and within 10 minutes is unconscious on our floor — there was no reason [for it].”

The province currently has no record of any Albertans under the age of 20 who have died of COVID-19.

According to the Strate family, the medical examiner is running additional blood and tissue tests, in an effort to uncover the cause of Sarah’s death.

‘Unusual but not impossible’

University of Alberta infectious disease specialist Dr. Lynora Saxinger, who was not involved in Sarah’s treatment, says it is conceivable that further testing could uncover evidence of a COVID-19 infection, despite two negative test results.

However, she hasn’t seen a similar case in Alberta.

“It would be unusual but not impossible because no test is perfect. We have had cases where an initial test is negative and then if you keep on thinking it’s COVID and you re-test, you then can find COVID,” she said.

According to Saxinger, the rate of false negatives is believed to be very low. But it can happen if there are problems with the testing or specimen collection.

She says people are more likely to test positive after symptoms develop. 

“The best sensitivity of the test is around day four or five of having symptoms,” she said. “So you can miss things if you test very, very early. And with new development of symptoms, it’s always a good time to re-test because then the likelihood of getting a positive test is a little higher. But again, no test is perfect.” 

Sarah deteriorated so quickly — dying five days after she first developed symptoms — she didn’t live long enough to make it to her follow-up COVID-19 test. Instead, it was done at the hospital.

‘An amazing kid’

The Strate family now faces an agonizing wait for answers — one that will likely take months — about what caused Sarah’s death.

But Ron, who teaches at the school where Sarah attended Grade 12, wants his daughter to be remembered for the life she lived, not her death.

Strate, pictured here at three years old, had plans to become a massage therapist. She attended Grade 12 at Magrath High School and was an active, healthy teenager who was involved in sports, music and the school’s suicide prevention group. (Ron Strate)

Sarah was one of five children. Ron says she was strong, active and vibrant and had plans to become a massage therapist after graduating from high school.

She played several sports and loved to sing and dance as part of a show choir. She was a leader in the school’s suicide prevention group and would stand up for other students who were facing bullying.

“She’s one of the leaders in our Hope Squad … which goes out and helps kids to not be scared,” he father said.

“She’s an amazing kid.”

Sarah would often spend hours helping struggling classmates, and her parents hope her kindness is not forgotten.

“She’d done so many good things. Honestly, I’ve got so many messages from parents saying, ‘You have no idea how much your daughter helped our kid,'” said Ron.

“This 17-year-old girl probably lived more of a life in 17 years than most adults will live in their whole lives. She was so special. I love her so much.”

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China launches key module of space station planned for 2022

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BEIJING (Reuters) -China launched an unmanned module on Thursday containing what will become living quarters for three crew on a permanent space station that it plans to complete by the end of 2022, state media reported.

The module, named “Tianhe”, or “Harmony of the Heavens”, was launched on the Long March 5B, China’s largest carrier rocket, at 11:23 a.m. (0323 GMT) from the Wenchang Space Launch Centre on the southern island of Hainan.

Tianhe is one of three main components of what would be China’s first self-developed space station, rivalling the only other station in service – the International Space Station (ISS).

The ISS is backed by the United States, Russia, Europe, Japan and Canada. China was barred from participating by the United States.

“(Tianhe) is an important pilot project in the building of a powerful nation in both technology and in space,” state media quoted President Xi Jinping as saying in a congratulatory speech.

Tianhe forms the main living quarters for three crew members in the Chinese space station, which will have a life span of at least 10 years.

The Tianhe launch was the first of 11 missions needed to complete the space station, which will orbit Earth at an altitude of 340 to 450 km (211-280 miles).

In the later missions, China will launch the two other core modules, four manned spacecraft and four cargo spacecraft.

Work on the space station programme began a decade ago with the launch of a space lab Tiangong-1 in 2011, and later, Tiangong-2 in 2016.

Both helped China test the programme’s space rendezvous and docking capabilities.

China aims to become a major space power by 2030. It has ramped up its space programme with visits to the moon, the launch of an uncrewed probe to Mars and the construction of its own space station.

In contrast, the fate of the ageing ISS – in orbit for more than two decades – remains uncertain.

The project is set to expire in 2024, barring funding from its partners. Russia said this month that it would quit the project from 2025.

Russia is deepening ties with China in space as tensions with Washington rise.

Moscow has slammed the U.S.-led Artemis moon exploration programme and instead chosen to join Beijing in setting up a lunar research outpost in the coming years.

(Reporting by Ryan Woo and Liangping Gao; Editing by Christian Schmollinger, Simon Cameron-Moore and Lincoln Feast.)

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