Tuesday, July 30, 2019
Saturday, July 27, 2019
A Close Call With An Asteroid
Forget about Mars, spend more time on asteroids!!
Alan Duffy was confused. On Thursday, the astronomer’s phone was suddenly flooded with calls from reporters wanting to know about a large asteroid that had just whizzed past Earth, and he couldn’t figure out “why everyone was so alarmed.”
“I thought everyone was getting worried about something we knew was coming,” Duffy, who is lead scientist at the Royal Institution of Australia, told The Washington Post. Forecasts had already predicted that a couple of asteroids would be passing relatively close to Earth this week.
Then, he looked up the details of the hunk of space rock named Asteroid 2019 OK.
“I was stunned,” he said. “This was a true shock.”
This asteroid wasn’t one that scientists had been tracking, and it had seemingly appeared from “out of nowhere,” Michael Brown, a Melbourne-based observational astronomer, told The Washington Post. According to data from NASA, the craggy rock was large, an estimated 57 to 130 meters wide (187 to 427 feet), and moving fast along a path that brought it within about 73,000 kilometers (45,000 miles) of Earth. That’s less than one-fifth of the distance to the moon and what Duffy considers “uncomfortably close.”
“It snuck up on us pretty quickly,” said Brown, an associate professor in Australia with Monash University’s School of Physics and Astronomy. He later noted, “People are only sort of realizing what happened pretty much after it’s already flung past us.”
The asteroid’s presence was discovered only earlier this week by separate astronomy teams in Brazil and the United States. Information about its size and path was announced just hours before it shot past Earth, Brown said.
“It shook me out my morning complacency,” he said. “It’s probably the largest asteroid to pass this close to Earth in quite a number of years.”
So how did the event almost go unnoticed?
First, there’s the issue of size, Duffy said. Asteroid 2019 OK is a sizable chunk of rock, but it’s nowhere near as big as the ones capable of causing an event like the dinosaurs’ extinction. More than 90 percent of those asteroids, which are more than half a mile wide or larger, have already been identified by NASA and its partners.
“Nothing this size is easy to detect,” Duffy said of Asteroid 2019 OK. ″You’re really relying on reflected sunlight, and even at closest approach it was barely visible with a pair of binoculars.”
Brown said the asteroid’s “eccentric orbit” and speed were also likely factors in what made spotting it ahead of time challenging. Its “very elliptical orbit” takes it “from beyond Mars to within the orbit of Venus,” which means the amount of time it spends near Earth where it is detectable isn’t long, he said. As it approached Earth, the asteroid was traveling at about 24 kilometers per second, he said, or nearly 54,000 mph. By contrast, other recent asteroids that flew by Earth clocked in between 4 and 19 kilometers per second (8,900 to 42,500 mph).
“It’s faint for a long time,” Brown said of Asteroid 2019 OK. “With a week or two to go, it’s getting bright enough to detect, but someone needs to look in the right spot. Once it’s finally recognized, then things happen quickly, but this thing’s approaching quickly so we only sort of knew about it very soon before the flyby.”
The last-minute detection is yet another sign of how much remains unknown about space and a sobering reminder of the very real threat asteroids can pose, Duffy said.
“It should worry us all, quite frankly,” he said. “It’s not a Hollywood movie. It is a clear and present danger.”
Duffy said astronomers have a nickname for the kind of space rock that just came so close to Earth: “City-killer asteroids.” If the asteroid had struck Earth, most of it would have probably reached the ground, resulting in devastating damage, Brown said.
“It would have gone off like a very large nuclear weapon” with enough force to destroy a city, he said. “Many megatons, perhaps in the ballpark of 10 megatons of TNT, so something not to be messed with.”
In 2013, a significantly smaller meteor — about 20 meters (65 feet) across, or the size of a six-story building — broke up over the Russian city of Chelyabinsk and unleashed an intense shock wave that collapsed roofs, shattered windows and left about 1,200 people injured. The last space rock to strike Earth similar in size to Asteroid 2019 OK was more than a century ago, Brown said. That asteroid, known as the Tunguska event, caused an explosion that leveled 2,000 square kilometers (770 square miles) of forest land in Siberia.
Although the chances of a large asteroid landing on a city are “modest,” Brown said it is still worthwhile to devote resources toward detection and prevention. Brown said Asteroid 2019 OK proves there are “still dangerous asteroids out there that we don’t know of” that “can arrive on our doorstep unannounced.”
Scientists are working on developing at least two approaches to deflecting potentially harmful asteroids, Duffy said. One strategy involves gently pushing the asteroid slowly over time off its course and away from Earth, he said. The other, which he called a “very elegant solution,” is the gravity tractor. If an asteroid is detected early enough, it could be possible to divert it using the gravity of a spacecraft, according to NASA.
People shouldn’t try to “blast it with a nuke,” Duffy said.
“It makes for a great Hollywood film,” he said. “The challenge with a nuke is that it may or may not work, but it would definitely make the asteroid radioactive.”
In light of Asteroid 2019 OK, Duffy stressed the importance of investing in a “global dedicated approach” to detecting asteroids because “sooner or later there will be one with our name on it. It’s just a matter of when, not if.”
“We don’t have to go the way of the dinosaurs,” he said. “We actually have the technology to find and deflect certainly these smaller asteroids if we commit to it now.”
Emily Lakdawalla, senior editor of the Planetary Society, which promotes space exploration, said the recent near miss is a reminder that “it’s an important activity to be watching the skies.” The more that can be learned about an asteroid, the better prepared people can be to prevent potential disasters, she told The Post.
Still, Lakdawalla said that while the asteroid’s close brush with Earth may have sparked some concern, “it is zero percent danger to us.”
“It’s the kind of thing where you learn about something that you didn’t know about, like things flying close by us, and your inclination is to be scared,” she said. “But just like sharks in the ocean, they’re really not going to hurt you and they’re really fascinating to look at.”
NASA's Mars 2020 Rover Does Biceps Curls
NASA's Mars 2020 Rover Does Biceps Curls: In this time-lapse video, the robotic arm on NASA's Mars 2020 rover maneuvers its 88-pound (40-kilogram) sensor-laden turret as it moves from a deployed to stowed configuration.
Thursday, July 25, 2019
Fueling of NASA's Mars 2020 Rover Power System Begins
Fueling of NASA's Mars 2020 Rover Power System Begins: NASA gives go-ahead to fuel the Mars 2020 rover's Multi-Mission Radioisotope Thermoelectric Generator - which powers rover and helps keep it warm exploring Mars.
Tuesday, July 23, 2019
What Does a Marsquake Look Like?
What Does a Marsquake Look Like?: InSight scientists used a special 'shake room' to demonstrate the differences between quakes on Earth, the Moon and Mars.
Sunday, July 21, 2019
Some Final Thoughts On The Apollo Program From Carl Sagan
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Jul 20, 2019, 7:39 AM (21 hours ago)
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Jack,
Today, we are celebrating one of the greatest days in human history: The day we stepped foot on the surface of the Moon. To celebrate with you, I wanted to share some wise words from my old Astronomy professor, Carl Sagan. He contributed the following article in 1994 while serving as President of The Planetary Society. It's a great reflection on the past, with a new perspective to take with us into the future:
—Bill
"The gates of Heaven are open wide; off I ride..."
Ch'u Tz'u (China, ca. 3rd century B.C.E.)
It's a sultry night in July. You've fallen asleep in the armchair. Abruptly, you startle awake, disoriented. The television set is on, but not the sound. You strain to understand what you're seeing. Two ghostly white figures in coveralls and helmets are softly dancing under a pitch-black sky. They make strange little skipping motions, which propel them upward amid barely perceptible clouds of dust. But something is wrong. They take too long to come down. Encumbered as they are, they seem to be flying—a little. You rub your eyes, but the dreamlike tableau persists.
Of all the events surrounding Apollo 11's landing on the Moon on July 20, 1969, my most vivid recollection is its unreal quality. Yes, it was an astonishing technological achievement and a triumph for the United States. Yes, the astronauts—Neil Armstrong, Buzz Aldrin and Mike Collins, the last keeping solitary vigil in lunar orbit—displayed death-defying courage. Yes, as Armstrong said as he first alighted, this was a historic step for the human species. But if you turned off the byplay between Mission Control and the Sea of Tranquility, with its deliberately mundane and routine chatter, and stared into that black-and-white television monitor, you could glimpse that we humans had entered the realm of myth and legend.
We knew the Moon from our earliest days. It was there when our ancestors descended from the trees into the savannahs, when we learned to walk upright, when we first devised stone tools, when we domesticated fire, when we invented agriculture and built cities and set out to subdue the Earth. Folklore and popular songs celebrate a mysterious connection between the Moon and love. Especially when we lived out-of-doors, it was a major—if oddly intangible—presence in our lives.
The Moon was a metaphor for the unattainable: "You might as well ask for the Moon," they used to say. For most of our history, we had no idea what it was. A spirit? A god? A thing? It didn't look like something big far away, but more like something small nearby—something the size of a plate, maybe, hanging in the sky a little above our heads. Walking on the Moon would have seemed a screwball idea; it made more sense to imagine somehow climbing up into the sky on a ladder or on the back of a giant bird, grabbing the Moon and bringing it down to Earth. Nobody ever succeeded, although there were myths aplenty about heroes who had tried.
Not until a few centuries ago did the idea of the Moon as a place, a quarter million miles away, gain wide currency. And in that brief flicker of time, we've gone from the earliest steps in understanding the Moon's nature to walking and joyriding on its surface. We calculated how objects move in space; liquefied oxygen from the air; invented big rockets, telemetry, reliable electronics, inertial guidance and much else. Then we sailed out into the sky.
The Moon is no longer unattainable. A dozen humans, all Americans, have made those odd bounding motions they called "moonwalks" on the crunchy, cratered, ancient gray lava- beginning on that July day in 1969. But since 1972, no one from any nation has ventured back. Indeed, none of us has gone anywhere since the glory days of Apollo except into low Earth orbit—like a toddler who takes a few tentative steps outward and then, breathless, retreats to the safety of his mother's skirts.
Once upon a time, we soared into the solar system. For a few years. Then we hurried back. Why? What happened? What was Apollo really about?
The scope and audacity of John Kennedy's May 25, 1961, message to a joint session of Congress on "Urgent National Needs"—the speech that launched the Apollo program—dazzled me. We would use rockets not yet designed and alloys not yet conceived, navigation and docking schemes not yet devised, in order to send a man to an unknown world—
a world not yet explored, not even in a preliminary way, not even by robots—and we would bring him safely back, and we would do it before the decade was over. This confident pronouncement was made before any American had even achieved Earth orbit.
As a newly minted PhD, I actually thought all this had something centrally to do with science. But President Kennedy did not talk about discovering the origin of the Moon, or even about bringing samples of it back for study. All he seemed to be interested in was sending someone there and bringing him home. It was a kind of gesture. Kennedy's science advisor, Jerome Wiesner, later told me he had made a deal with the president: if Kennedy would not claim that Apollo was about science, then he, Wiesner, would support it. So if not science, what?
The Apollo program is really about politics, others told me. This sounded more promising. Nonaligned nations would be tempted to drift toward the Soviet Union if it was ahead in space exploration, if the U.S. showed insufficient "national vigor." I didn't follow. Here was the United States, ahead of the Soviet Union in virtually every area of technology—the world's economic, military and, on occasion, even moral leader—and Indonesia would go Communist because Yuri Gagarin beat John Glenn to Earth orbit? What's so special about space technology? Suddenly I understood.
Sending people to orbit the Earth or robots to orbit the Sun requires rockets-big, reliable, powerful rockets. Those same rockets can be used for nuclear war. The same technology that transports a man to the Moon can carry nuclear warheads halfway around the world. The same technology that puts an astronomer and a telescope in Earth orbit can also put up a laser "battle station."
Even back then, there was fanciful talk in military circles, East and West, about space as the new "high ground," about the nation that "controlled" space "controlling" the Earth. Of course strategic rockets were already being tested on Earth. But heaving a ballistic missile with a dummy warhead into a target zone in the middle of the Pacific Ocean doesn't buy much glory. Sending people into space captures the attention and imagination of the world. You wouldn't spend the money to launch astronauts for this reason alone, but of all the ways of demonstrating rocket potency, this one works best. It was a rite of national manhood; the shape of the boosters made this point readily understood without anyone actually having to explain it. The communication seemed to be transmitted from unconscious mind to unconscious mind without the higher mental faculties catching a whiff of what was going on.
When President Kennedy formulated the Apollo program, the Defense Department had a slew of space projects under development—ways of carrying military personnel up into space, ways of conveying them around the Earth, robot weapons on orbiting platforms intended to shoot down satellites and ballistic missiles of other nations. Apollo supplanted these programs. They never reached operational status. A case can be made then that Apollo served another purpose—to move the US-Soviet space competition from a military to a civilian arena. There are some who believe that Kennedy intended Apollo as a substitute for an arms race in space. Maybe.
Six more missions followed Apollo 11, all but one of which successfully landed on the lunar surface. Apollo 17 was the first to carry a scientist. As soon as he got there, the program was canceled. The first scientist and the last human to land on the Moon were the same person. The program had already served its purpose that July night in 1969. The half-dozen subsequent missions were just momentum.
Apollo was not mainly about science. It was not even mainly about space. Apollo was about ideological confrontation and nuclear war—often described by such euphemisms as world "leadership" and national "prestige." Nevertheless, good space science was done. We now know much more about the composition, age and history of the Moon and the origin of the lunar landforms. We have made progress in understanding where the Moon came from. Some of us have used lunar cratering statistics to better understand the Earth at the time of the origin of life. But more important than any of this, Apollo provided an aegis, an umbrella under which brilliantly engineered robot spacecraft were dispatched throughout the solar system, making that preliminary reconnaissance of dozens of new worlds. The offspring of Apollo have now reached the planetary frontiers.
If not for Apollo—and, therefore, if not for the political purpose it served—I doubt whether the historic American expeditions of exploration and discovery throughout the solar system would have occurred. The Mariners, Vikings, Voyagers, Magellan, Galileo and Cassini are among the gifts of Apollo. Something similar is true for the pioneering Soviet efforts in solar system exploration, including the first soft landings of robot spacecraft—Luna 9, Mars 3, Venera 8—on other worlds.
Apollo conveyed a confidence, energy and breadth of vision that did capture the imagination of the world. That too was part of its purpose. It inspired an optimism about technology, an enthusiasm for the future. If we could go to the Moon, what else was now possible? Even those who were not admirers of the United States readily acknowledged that—whatever the underlying reason for the program—the nation had, with Apollo, achieved greatness.
When you pack your bags for a big trip, you never know what's in store for you. The Apollo astronauts on their way to and from the Moon photographed their home planet. It was a natural thing to do, but it had consequences that few foresaw. For the first time, the inhabitants of Earth could see their world from above—the whole Earth, Earth in color, Earth as an exquisite spinning white and blue ball set against the vast darkness of space. Those images helped awaken our slumbering planetary consciousness. They provide incontestable evidence that we all share the same vulnerable planet. They remind us of what is important and what is not.
We may have found that perspective just in time, just as our technology threatens the habitability of our world. Whatever the reason we first mustered the Apollo program, however mired it was in Cold War nationalism and the instruments of death, the inescapable recognition of the unity and fragility of Earth is its clear and luminous dividend, the unexpected final gift of Apollo. What began in deadly competition has helped us to see that global cooperation is the essential precondition for our survival.
Travel is broadening.
It's time to hit the road again.
- Carl Sagan
Founder and First President for The Planetary Society
This article was adapted from a chapter Carl Sagan's book, Pale Blue Dot: A Vision of the Human Future in Space. It was originally featured in the May/June 1994 issue of the Planetary Society member magazine, The Planetary Report.
Onward! As Carl says, "It's time to hit the road again."
Bill Nye, CEO
The Planetary Society |
Friday, July 19, 2019
Nuke The Moon-A Wild 1960's Project!!!
Inside Project A119, the secret US plan to detonate a nuclear bomb on the Moon
Landing on the Moon was option B.Long before JFK spoke inspiringly of sending humans to the Moon, the American intelligence community was concocting a very different plan.
Option A was to detonate a nuke on it.
In the late 1950s, Washington set in place a secret operation to examine the feasibility of detonating a thermonuclear device on the surface of our closest celestial neighbour.
It was codenamed Project A119.
Had it gone ahead, the expression "shooting for the Moon" would have gained a whole new meaning.
A spectacular scheme born of desperation
What might now seem unimaginable only makes sense in the context of the Cold War, historian Vince Houghton says.
Paranoia and distrust had reached fever pitch on both sides of the Iron Curtain by the late 1950s, and military one-upmanship was the order of the day.
The United States and its arch-nemesis the Soviet Union were at loggerheads, vying for global supremacy.
In 1956, while addressing a gathering of Western ambassadors, Soviet leader Nikita Khrushchev declared: "Whether you like it or not, history is on our side. We will bury you!"
His blunt message sent a chill down the collective international spine.
"These were times when true desperation played a role in our decision-making," says Dr Houghton, curator of the International Spy Museum in Washington.
The situation went to Code Red in October of 1957 when the USSR successfully launched the world's first satellite, Sputnik.
The deployment caught the world by surprise. It was not only a great technological achievement, but was intended as a symbol of Russian superiority.
"The Americans and the West were terrified of the concept that potentially the Soviets had beaten us at our own game," Dr Houghton says.
"We'd always been the big kids in science and technology, the people who had invented new and innovative things. All of a sudden the Soviets had beaten us into space."
Doubling the sense of threat was the fact that Sputnik had been launched into orbit on what was essentially an intercontinental ballistic missile.
"The West was given a shock with the launch of Sputnik and very quickly the US Government flew into action and said we need to do something very spectacular," Dr Houghton says.
"We need to do something so big that the whole world will know that this was just an anomaly, that Sputnik was just a blip, that the United States was still the big kid on the block."
And with that, Project A119 was born.
One hell of a mushroom
The idea behind the project was ambitious, but simple — to create an explosion and lunar mushroom cloud so awe-inspiring and unavoidable that no matter where you lived on planet Earth, it would be impossible to ignore the extent of America's military and technological might.
Appointed to lead the project was a physicist named Leonard Reiffel, who later went on to become the deputy director of the Apollo Program at NASA.
Carl Sagan, the famous author and celebratory science communicator, was also on the team, though at the time he was a young and little-known astrophysicist.
It's been speculated that a secondary aspect of the project was to provide insights into the geological sub-structure of the Moon's surface.
Protectors of the late Dr Sagan's considerable reputation have suggested that his real interest was in exploring whether such an explosion might unearth signs of unknown lifeforms beneath the lunar crust.
Dr Houghton says when delivering the initial findings in June 1959, cost was among the major reasons why the project was scuttled.
But he says there were also concerns about damaging the lunar landscape.
"There were some scientists who said: 'You know, we might want to walk up there some day. Maybe we don't want to blow the hell out of it before we do,'" he says.
"But, again, Sputnik was so terrifying that a lot of people were willing to take that chance.
"A lot of people were willing to say: 'You know what? The Moon's big enough that we can nuke it and land on it at the same time, so let's give this a shot.'"
The big bang that fizzed
Dr Reiffel's secret report into the feasibility of a lunar detonation was eventually declassified in 2000.
It suggested that detonating a nuclear device on the Moon was technically feasible, but it gave no substantive detail as to how it might be done.
The project never proceeded to operational phase.
Interviewed by The Guardian shortly after the report's declassification, Dr Reiffel expressed his personal relief.
"I am horrified that such a gesture to sway public opinion was ever considered," he said.
"Had the project been made public there would have been an outcry.
"I made it clear at the time there would be a huge cost to science of destroying a pristine lunar environment, but the US Air Force were mainly concerned about how the nuclear explosion would play on Earth."
Dr Houghton says it's important to view Project A119 in its historical context.
He details the operation in a new book called Nuking the Moon, which examines a whole slate of radical intelligence projects that were set in motion during WWII and the Cold War, but which were never carried out.
Another involved dropping thousands of bats with incendiary devices strapped to their bodies over Tokyo and other Japanese cities.
While they might seem odd in hindsight, even extreme, he says the projects were born of a need to be creative in meeting a series of genuine military and political threats.
"That's really what intelligence agencies are designed to do. They're designed to provide policymakers with information that prevents us from getting surprised," he says.
"So, [intelligence communities] better be thinking way outside of the box. They better be thinking not only about what technologies we might want to use one day, but also what technologies somebody might want to use against us."
That may be true, but from a post-Cold War perspective, it's hard not to conclude that, way back in the late 1950s, the Moon really did dodge a bullet — so to speak.
Thursday, July 18, 2019
50 Years Ago I Met Buzz Aldrin And Neil Armstrong
50 years ago when I was a young man of 20 years I got to meet Buzz Aldrin and Neil Armstrong. I went to Buzz's house in May of 1969 before he flew to the moon. Buzz lived in an elegant 2-story house that was just short of being a wealthy man's mansion. He drove a very-expensive Chevrolet Corvette sports car. When I knocked on the door, he came to the door. He was dressed in a leisure suit. My first impression was: "Oh my God this man is so handsome that he should be a movie star." Buzz greeted me warmly. He invited me into the house. He led me to the living room. He told me to take a seat on the couch. He introduced me to his then-wife Joan. He gave me a coke. We had a nice talk and he gave me an autograph before I left.
After the moon landing in August of 1969, I went to Neil Armstrong's house. Neil lived in a very-modest one-story house quite similar to the house where my sister and I grew up. Neil drove a 1954 white Chevrolet coupe. When I came to the house, Neil was dressed in khaki pants and a white undershirt. He was working on his Chevy coupe. I told him that it was an honor to meet him. He was very polite and even kind to me. He told me that Neil Armstrong had lived in the house, but had moved away a few months before. I saw that I was going to get nowhere. I apologized to him for bothering him and left. It took me 49 years to get an autographed picture of Neil. They are rare.
Wednesday, July 17, 2019
Dr. Robert Zubrin On The Apollo 11 Anniversary
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Spend The Money for Manned Mars Missions On Social Programs?????
Dear Ron:
Elena would agree with you. I once read a brilliant little book by the author Mary Roach. It's title was Packing For Mars. This lady literally put her heart and her soul into this project. She went to Russia and trained to be a cosmonaut. She qualified to fly on the Soyuz spacecraft but would have had to pay $20 million to actually take a flight. She went to the Johnson Space Center and took US astronaut training including a two-week course on how to use the toilet on the international space station.
The ending of the book produced a real pearl of wisdom. She talked about how cold and inhospitable space was. She talked about how dangerous a long-duration spaceflight was for humans. She kept talking about all the negatives. I was sure that the book was going to end saying that we should not send human missions to Mars. Then she surprised the hell out of me with the final words in the book:
"Oh well, if we don't send humans to Mars, they won't spend that money on social programs. What the heck, we might as well go ahead and do it."
Ron if I was in court now, my words would be: "I rest my case."
With kindest regards,
Tuesday, July 16, 2019
Want to Colonize Mars? Aerogel Could Help
Want to Colonize Mars? Aerogel Could Help: Researchers are studying whether a wonder material used in Mars rovers could help warm parts of the Red Planet rich in water ice.
Saturday, July 13, 2019
Tuesday, July 9, 2019
Tuesday, July 2, 2019
Mars 2020 Rover Gets a Super Instrument
Mars 2020 Rover Gets a Super Instrument: With its rock-zapping laser, the SuperCam will enable the science team to identify the chemical and mineral makeup of its targets on the Red Planet.
Methane On Mars-A Plume Came And A Plume Went
A Plume Came, a Plume Went
Two weeks ago, NASA’s Curiosity rover on Mars detected a spike in the level of methane gas in the atmosphere above the planet’s Gale Crater.
Scientists grew excited at the high concentration of the gas, suggesting it might be a sign of microbial life.
But, alas, the gas simply dissipated a few days later, leaving astronomers puzzled as to whether Earth’s neighbor harbors any signs of life.
“A plume came and a plume went,” Paul Mahaffy of NASA’s Goddard Space Flight Center told scientists at a conference, according to the New York Times.
The space agency’s Mars rovers and orbiters are constantly searching for traces of methane in the red planet’s atmosphere, with varying degrees of luck.
In 2013, they registered a spike of up to 7 parts per billion that lasted at least two months – the recent one was 21 parts per billion.
Methane, mostly known as natural gas, can be produced by microbes, such as those living in the guts of animals, or through geological processes.
Astronomers are unsure where Mars’ methane is coming from and what’s producing it, but they are determined to find out.
Maybe it was just a burp.
“The methane mystery continues,” Ashwin R. Vasavada, a mission project scientist, declared in a statement.
NASA's InSight Uncovers the 'Mole'
NASA's InSight Uncovers the 'Mole': The lander's robotic arm has successfully removed a piece of hardware blocking the view of its digging device in order to help with recovery efforts.
A Neil Armstrong for Mars: Landing the Mars 2020 Rover
A Neil Armstrong for Mars: Landing the Mars 2020 Rover: NASA's newest rover will have an autopilot called Terrain-Relative Navigation.
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