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Automated Technology Allows Unparalleled Space Exploration from Moon, to Asteroids, and Beyond – SciTechDaily

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Overhead view of OSIRIS-REx at sample site Nightingale, with a parking lot for comparison. Credit: NASA/Goddard/CI Lab/University of Arizona

When landing Apollo 11 in 1969, astronauts looked out the window for distinguishing features that they recognized from maps of the Moon and were able to steer the lander to avoid a disastrous touchdown on top of a rocky area. Now, 50 years later, the process can be automated. Distinguishing features, like known craters, boulders, or other unique surface characteristics, provide insight into surface hazards to help avoid them while landing.

NASA scientists and engineers are maturing technology for navigating and landing on planetary bodies by analyzing images during descent – a process called terrain relative navigation (TRN). This optical navigation technology is included on NASA’s newest Mars rover, Perseverance, which will test TRN when it lands on the Red Planet in 2021, paving the way for future crewed missions to the Moon and beyond. TRN was also being used during NASA’s recent Origins, Spectral Interpretation, Resources Identification, Security, Regolith Explorer (OSIRIS-REx) mission Touch-and-Go (TAG) event to collect samples of the asteroid Bennu in order to better understand the characteristics and movement of asteroids.

Since reaching Bennu in 2018, the OSIRIS-REx spacecraft has mapped and studied its surface, including its topography and lighting conditions, in preparation for TAG. Nightingale crater was chosen from four candidate sites based on its great amount of sampleable material and accessibility for the spacecraft.

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On October 20, the OSIRIS-REx spacecraft successfully navigated to asteroid Bennu’s surface and collected a sample. Credit: NASA’s Goddard Space Flight Center/Scientific Visualization Studio

Engineers routinely use ground-based optical navigation methods to navigate the OSIRIS-REx spacecraft close to Bennu, where new images taken by the spacecraft are compared to three-dimensional topographic maps. During TAG, OSIRIS-REx performed a similar optical navigation process onboard in real-time, using a TRN system called Natural Feature Tracking. Images were taken of the sample site during TAG descent, compared with onboard topographic maps, and the spacecraft trajectory was readjusted to target the landing site. Optical navigation could also be used in the future to minimize the risks associated with landing in other unfamiliar environments in our solar system.

NASA’s Lunar Reconnaissance Orbiter (LRO) has acquired images from orbit since 2009. LRO Project Scientist Noah Petro said one challenge to preparing for landed missions is the lack of high-resolution, narrow-angle camera images at every lighting condition for any specific landing site. These images would be useful for automated landing systems, which need the illumination data for a specific time of lunar day. However, NASA has been able to collect high-resolution topographic data using LRO’s Lunar Orbiter Laser Altimeter (LOLA).

“LOLA data, and other topographic data, let us take the shape of the Moon and shine a light on it for any time in the future or past, and with that we can predict what the surface will look like,” Petro said.

Artemis Astronaut on Moon

Artist concept of Artemis astronaut stepping onto the Moon. Credit: NASA

Using LOLA data, sun angles are overlaid on a three-dimensional elevation map to model shadows of surface features at specific dates and times. NASA scientists know the position and orientation of the Moon and LRO in space, having taken billions of lunar laser measurements. Over time, these measurements are compiled into a grid-map of the lunar surface. Images taken during landing are compared to this master map so that landers that may be used as part of the Artemis program have another tool to safely navigate the lunar terrain.

The lunar surface is like a fingerprint, Petro said, where no two landscapes are identical. Topography can be used to determine a spacecraft’s exact location above the Moon, comparing images like a forensic scientist compares fingerprints from crime scenes to match a known person to an unknown person – or to match a location to where the spacecraft is in its flight.

After landing, TRN can be used on the ground to help astronauts navigate crewed rovers. As part of NASA’s lunar surface sustainability concept, the agency is considering using a habitable mobility platform like an RV as well as a lunar terrain vehicle (LTV) to help crew travel on the lunar surface.

Astronauts can typically travel short distances of a few miles in an unpressurized rover like the LTV so long as they have landmarks to guide them. However, traveling greater distances is much more challenging, not to mention the Sun at the lunar South Pole is always low on the horizon, adding to visibility challenges. Driving across the South Pole would be like driving a car straight east first thing in the morning – the light can be blinding, and landmarks can appear distorted. With TRN, astronauts may be better able to navigate the South Pole despite the lighting conditions, as the computer may better detects hazards.

Speed is the key difference between using TRN to land a spacecraft and using it to navigate a crewed rover. Landing requires capturing and processing images faster, with as short as one second intervals between images. To bridge the gap between images, onboard processors keep the spacecraft on track to safely land.

“When you move slower – such as with rovers or OSIRIS-REx orbiting around the asteroid – you have more time to process the images,” said Carolina Restrepo, an aerospace engineer at NASA Goddard in Maryland working to improve current data products for the lunar surface. “When you are moving very fast – descent and landing – there is no time for this. You need to be taking images and processing them as fast as possible aboard the spacecraft and it needs to be all autonomous.”

Automated TRN solutions can address the needs of human and robotic explorers as they navigate unique locations in our solar system, such as the optical navigation challenges faced by OSIRIS-REx for TAG on Bennu’s rocky surface. Because of missions like LRO, Artemis astronauts can use TRN algorithms and lunar topography data to supplement images of the surface in order to land and safely explore the Moon’s South Pole.

“What we’re trying to do is anticipate the needs of future terrain relative navigation systems by combining existing data types to make sure we can build the highest-resolution maps for key locations along future trajectories and landing sites,” Restrepo said. “In other words, we need high-resolution maps both for scientific purposes as well as for navigation.”

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Chinese national flag debuts on moon: CNSA – Global Times

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Photo:CNSA

The China National Space Administration (CNSA) on Friday showed photos of the first Chinese national flag on the moon. The photo was taken with the flag on board the Chang’e-5 lander vehicle before the ascender blasted off from the moon, marking another proud, inspiring moment in the memories of the Chinese people. 

As soon as the photo was released, it brought cheers from Chinese netizens on twitter-like Sina Weibo. As thousands of netizens left emojis of hearts, clapping hands, and celebrating ribbons on the social platform, some said “if there’s a color for a miracle, it must be the color red on our Chinese national flag.”

The flag, more stylish than before, was made from some special material and weighs only 12 grams. It is the third time that the five-starred red flag on the moon following the mission’s two predecessors, chang’e-3 and -4. Only this time, it comes in the form of actual fabrics other than previous coating on.

The Chinese national flag made its moon debut in December 2013 during the country’s first lunar landing mission of Chang’e-3, and it was recorded in pictures from the spacecraft’s lander and its rover Yutu-1 took for each other.

Chang’e-4 lander and rover Yutu-2 brought China’s national flag to the dark side of the moon, as the Chinese spacecraft made a historic landing in the unvisited region in January 2019.

The flags that Chang’e-3 and -4 carried were in the form of the craft’s coatings, rather than an actual flag. Chinese space technological development has allowed it to take a step forward in the Chang’e-5 mission, the third consecutive safe soft landing on the moon in seven years. 

The Chang’e-5 flag presentation system was developed by China Space Sanjiang Group under the State-owned China Aerospace Science and Industry Corporation, better known as the CASIC.

To ensure a complete and smooth unfolding of the flag, the system adopted a secondary rod-type structure, which is applied in solar panel extending for satellites and other types of spacecraft, CASIC developers told the Global Times on Thursday.

The system weight has been controlled at around one kilogram, and all connecting parts of the system have been given special protection, such as coldness-resistance measures, to help overcome unfavorable lunar surface conditions, including a drastic temperature difference on the moon ranging from 150 C to minus 150 C, Li Yunfeng, the project leader, said in a statement the CASIC company sent to the Global Times.

“An ordinary national flag on Earth would not survive the severe lunar environment,” so the research team also spent more than a year selecting the proper materials to make sure the eventual flag would be strong enough, survive under extreme coldness and heat and capable of showing the fine colors of the national flag and remain so forever, said Cheng Chang, another leading member of the developer team.

The 12-gram national flag represents cutting-edge technology, they said.

How to preserve its original color and shape are the two most crucial questions in designing a national flag that must survive more than 380,000 kilometers away from Earth, under extreme temperatures and radiation during its journey, Wang Ya’nan told the Global Times. 

To get a sense of how difficult the task it is, five of the six flags (except for the one Apollo 11 placed on the moon) brought to the moon in the late 1960s and early 1970s during six US crewed moon landings, have been bleached white due to decades-long solar radiation, although they are reportedly still standing and casting shadows.

Many reports say the Apollo 11 flag was blown over by the exhaust from the ascent engine during lift-off.

The Soviet Union was the first country to imprint its national symbol on the moon, with a football-sized metal ball, carved with its national flag, full of explosives, smashing to the lunar ground in the Luna 2 mission in 1959.

Compared to such a method, China has a more advanced approach, which also greatly increased the complexity of the design, Wang noted.

The Chinese flag that Chang’e-5 displayed officially became the first and only fabric national flag that has ever been placed on the moon in the 21st century, which reminds many of the classic footage of an American national flag planted by Neil Armstrong in the Apollo 11 lunar mission more than five decades ago, observers said.

And they hailed that as the fresh and new icon of human’s lunar exploration, the Chinese national flag would inspire today’s mankind, just as Apollo 11 did, encourage and celebrate generations to make an endeavor to space. 

Displaying a national flag on a celestial body represents the comprehensive strength and technological advancement of the country, Song Zhongping, an aerospace expert and TV commentator, told the Global Times. 

“Yesterday’s memory is still fresh and clear, when the US astronauts stepped outside their cabins and planted the first flag in human history, an American national flag, on the moon in 1969,” Song recalled. “But China is about to showcase our own national flag as well, which I believe is a recognition of the achievements and breakthroughs that we have made, which will be the most valuable thing.”

Some readers have left comments under images and video of the Chang’e-5 landing published on the Global Times twitter account in recent days, saying they would not be convinced and acknowledge China’s achievements until the lander takes an actual photo of the American flag planted by the previous Apollo mission. 

“Is it an original video, or a TikTok post taken in the Gobi desert,” one Twitter user wrote. “Where is the lunar dust while landing,” another asked.

The landing was closely followed by space agencies from all over the world, and the European Space Agency, Russia’s Roscosmos and NASA scientists have extended their congratulations.

Pang Zhihao, a senior space expert based in Beijing, said “the lander vehicle of Chang’e-5 was designed to turn off its engine about two meters above the surface to deliberately avoid blowing dirt.”

And for the sake of innovation, the lander touched down on an unvisited region, which explains why there were no US craft nearby, Pang said.

Global Times

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Footage shows catastrophic collapse of iconic Puerto Rico telescope – cjoy.com

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Dramatic video from Puerto Rico captures the moment when a 816-tonne platform came crashing down on the Arecibo Observatory, shattering one of the world’s largest telescopes and striking a crushing blow to the global scientific community.

The catastrophic collapse happened on Dec. 1, less than two weeks after the U.S. National Science Foundation (NSF) warned that such a disaster was imminent. The NSF had already shuttered operations at the facility after a suspension cable snapped and slashed a hole in the dish last month.

Read more:
Massive Puerto Rico radio telescope collapses after cables snap

The telescope was the largest of its kind when it opened in 1963, and it has contributed to all manner of astronomical discoveries over the years, from asteroids to planets to mysterious radio signals in space. It also won a place in pop culture as the set for such films as Contact and GoldenEye, the first James Bond movie starring Pierce Brosnan.

The observatory’s telescope consisted of a 816-tonne reflector dish platform suspended 137 metres above a massive, bowl-like dish, which measured 305 metres across.

Suspension cables holding up the platform snapped on Dec. 1, dropping the heavy platform on the dish with a tremendous crash.

Video captured by the Arecibo control tower shows one of the three major cables snapping, causing the platform to swing down on the remaining cables before snapping them, too.

The footage shows the reflector dish platform falling apart in mid-air, while dragging down several support towers behind it.

Drone footage captured from one of the support towers shows the moment when the first cable snapped. The cable snapped at the tower, then the whole structure came crashing down, pulling other towers with it and cracking the bowl of the telescope. Large clouds of dust rose from the bowl after the catastrophe.

Read more:
Mysterious radio signal from space traced to ‘zombie’ in our galaxy

Jonathan Friedman, who worked for 26 years at the facility and still lives nearby, described the awful sound of the collapse in an interview with the Associated Press.

“It sounded like a rumble. I knew exactly what it was,” he said. “I was screaming. Personally, I was out of control. … I don’t have words to express it. It’s a very deep, terrible feeling.”

Many scientists, Puerto Rico residents and other public figures mourned the telescope’s loss after it was closed, and again after it collapsed.

Ángel Vázquez, the telescope’s director of operations, said it was no surprise when the telescope fell apart early Tuesday.

“It was a snowball effect,” he said. “There was no way to stop it. … It was too much for the old girl to take.”

© 2020 Global News, a division of Corus Entertainment Inc.

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Footage shows catastrophic collapse of iconic Puerto Rico telescope – Global News

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 on


Dramatic video from Puerto Rico captures the moment when a 816-tonne platform came crashing down on the Arecibo Observatory, shattering one of the world’s largest telescopes and striking a crushing blow to the global scientific community.

The catastrophic collapse happened on Dec. 1, less than two weeks after the U.S. National Science Foundation (NSF) warned that such a disaster was imminent. The NSF had already shuttered operations at the facility after a suspension cable snapped and slashed a hole in the dish last month.

Read more:
Massive Puerto Rico radio telescope collapses after cables snap

The telescope was the largest of its kind when it opened in 1963, and it has contributed to all manner of astronomical discoveries over the years, from asteroids to planets to mysterious radio signals in space. It also won a place in pop culture as the set for such films as Contact and GoldenEye, the first James Bond movie starring Pierce Brosnan.

Story continues below advertisement

The observatory’s telescope consisted of a 816-tonne reflector dish platform suspended 137 metres above a massive, bowl-like dish, which measured 305 metres across.

Suspension cables holding up the platform snapped on Dec. 1, dropping the heavy platform on the dish with a tremendous crash.






0:43
Aerial footage shows damage caused by Arecibo radio telescope collapse


Aerial footage shows damage caused by Arecibo radio telescope collapse

Video captured by the Arecibo control tower shows one of the three major cables snapping, causing the platform to swing down on the remaining cables before snapping them, too.

The footage shows the reflector dish platform falling apart in mid-air, while dragging down several support towers behind it.

Drone footage captured from one of the support towers shows the moment when the first cable snapped. The cable snapped at the tower, then the whole structure came crashing down, pulling other towers with it and cracking the bowl of the telescope. Large clouds of dust rose from the bowl after the catastrophe.

Story continues below advertisement

Read more:
Mysterious radio signal from space traced to ‘zombie’ in our galaxy

Jonathan Friedman, who worked for 26 years at the facility and still lives nearby, described the awful sound of the collapse in an interview with the Associated Press.

“It sounded like a rumble. I knew exactly what it was,” he said. “I was screaming. Personally, I was out of control. … I don’t have words to express it. It’s a very deep, terrible feeling.”

Many scientists, Puerto Rico residents and other public figures mourned the telescope’s loss after it was closed, and again after it collapsed.

Ángel Vázquez, the telescope’s director of operations, said it was no surprise when the telescope fell apart early Tuesday.

“It was a snowball effect,” he said. “There was no way to stop it. … It was too much for the old girl to take.”

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© 2020 Global News, a division of Corus Entertainment Inc.

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