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Seven Minutes of Terror: Engineering the Mars Rover's Impossible Landing
NASA engineer Adam Steltzner is driving his team to attempt the seemingly impossible.
Here's an interesting engineering challenge. Fly an unmanned spacecraft carrying a 2,000 pound rover 300 million miles to Mars. Smash into the planet's extremely thin atmosphere at 13,000 mph, which will light up the craft's heat shield like the sun, reaching temperatures of 1,600 degrees. The atmosphere will slow your craft down to about 1,000 mph, but you will need to figure out a way to eventually slow to zero, jettison the heat shield and simultaneously guide the ship to a safe landing in the constrained space of the Gale crater.
A supersonic parachute will slow you down to 200 mph, but you're still coming in too hot for a landing. It's time to exercise your pyrotechnic devices, blasting rockets to divert the craft away from the parachute. These rockets can't get too close to the ground because they might create a massive dust cloud and damage the rover's equipment. So a sky crane will have to gently lower the rover to the surface (A so-called 'rover on a rope': is it genius or crazy or a lot of both?).
This sequence is dramatized in a thrilling video below, which NASA's Jet Propulsion Lab has dubbed the "seven minutes of terror," as it will take seven minutes for the craft to travel from the top of the atmosphere to the surface of the planet. It will take 14 minutes to transmit the signal back to Earth, meaning you will have to wait in agonizing uncertainty for seven minutes, not knowing whether your $2.5 billion mission is a success or failure.
You give up? No one would blame you.
Adam Steltzner did not give up. In fact, the NASA engineer has spent the last nine years of his life leading a team to solve this problem. Given the margin for error -- which is zero -- it is a good thing that Steltzner is a cool cat, which is how NPR described him in a recent profile. We are rooting for his efforts to come to fruition early Monday, when the Mars rover is scheduled to complete its nine-month journey. On the other hand, if anything goes wrong in the sequence described above, Steltzner's mission will fail. Like those odds?
Watch the video here:
What's the Big Idea?
The highly complex field of spacecraft engineering, not surprisingly, is clouded with the kind of jargon The Associated Press describes as "a sort of Martian alphabet soup."
Steltzner's team is responsible for EDL, or Entry, Decent and Landing, the crucial phase of the Curiosity mission outlined in the video above. Steltzner's team had to custom design a landing system for a rover that is five times heavier than previous ones sent to Mars. They also had to contend with the challenge of the Red Planet's extremely thin atmosphere. A new parachute and rocket system had to be custom designed as well. And yet, the team's signature innovation is the way it all works together.
Therefore, if successful, this mission will be the triumph of both teamwork and leadership. The teamwork involved nearly a decade of tinkering the system's design. The leadership has come from the steady hand of Steltzner, who traded a career in rock n' roll for physics. His former career as a bassist appears to be suiting him well at NASA. In the face of adversity, Steltzner advises his team to keep themselves "like, chill, and focused and not freaking."
Two out of every three missions to Mars end in failure. Hero or goat, we commend Steltzner for driving his team to attempt the seemingly impossible, and will be inviting him to appear on Big Think.
As X Prize Founder and space pioneer Peter Diamandis tells us below, every radical breakthrough began as "a crazy idea." The commercial space industry is a perfect example. People didn't want to invest in the idea because they didn't believe it was possible. From a leadership standpoint, Diamandis tells us, you need to make people believe it is possible.
Watch the video here:
What's the Significance?
The significance of the Curiosity rover mission is twofold. If NASA's team is able to successfully complete this engineering challenge, the landing will be a feat unto itself. Furthermore, if Curiosity isn't consumed in a fireball, the machine will go on to conduct a geological survey of the planet for one Martian year (or 687 Earth days). Its first discovery might be imminent. Curiosity is touching down on the Gale Crater because scientists believe the sediment there will contain evidence that there was once a habitable environment on Mars.
You can give yourself a front row seat in a video game that resulted from a partnership between NASA and Microsoft called The Mars Rover Landing. The game is available as a free download at Xbox Live. NASA's engineers describe the gaming experience as very similar to what the actual landing will be like.
Image courtesy of NASA
Follow Daniel Honan on Twitter @Daniel Honan
What is human dignity? Here's a primer, told through 200 years of great essays, lectures, and novels.
- Human dignity means that each of our lives have an unimpeachable value simply because we are human, and therefore we are deserving of a baseline level of respect.
- That baseline requires more than the absence of violence, discrimination, and authoritarianism. It means giving individuals the freedom to pursue their own happiness and purpose.
- We look at incredible writings from the last 200 years that illustrate the push for human dignity in regards to slavery, equality, communism, free speech and education.
The inherent worth of all human beings<p>Human dignity is the inherent worth of each individual human being. Recognizing human dignity means respecting human beings' special value—value that sets us apart from other animals; value that is intrinsic and cannot be lost.</p> <p>Liberalism—the broad political philosophy that organizes society around liberty, justice, and equality—is rooted in the idea of human dignity. Liberalism assumes each of our lives, plans, and preferences have some unimpeachable value, not because of any objective evaluation or contribution to a greater good, but simply because they belong to a human being. We are human, and therefore deserving of a baseline level of respect. </p> <p>Because so many of us take human dignity for granted—just a fact of our humanness—it's usually only when someone's dignity is ignored or violated that we feel compelled to talk about it. </p> <p>But human dignity means more than the absence of violence, discrimination, and authoritarianism. It means giving individuals the freedom to pursue their own happiness and purpose—a freedom that can be hampered by restrictive social institutions or the tyranny of the majority. The liberal ideal of the good society is not just peaceful but also pluralistic: It is a society in which we respect others' right to think and live differently than we do.</p>
From the 19th century to today<p>With <a href="https://books.google.com/ngrams/graph?year_start=1800&year_end=2019&content=human+dignity&corpus=26&smoothing=3&direct_url=t1%3B%2Chuman%20dignity%3B%2Cc0" target="_blank" rel="noopener noreferrer">Google Books Ngram Viewer</a>, we can chart mentions of human dignity from 1800-2019.</p><img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDg0ODU0My9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY1MTUwMzE4MX0.bu0D_0uQuyNLyJjfRESNhu7twkJ5nxu8pQtfa1w3hZs/img.png?width=980" id="7ef38" class="rm-shortcode" data-rm-shortcode-id="9974c7bef3812fcb36858f325889e3c6" data-rm-shortcode-name="rebelmouse-image" />
American novelist, writer, playwright, poet, essayist and civil rights activist James Baldwin at his home in Saint-Paul-de-Vence, southern France, on November 6, 1979.
Credit: Ralph Gatti/AFP via Getty Images
The future of dignity<p>Around the world, people are still working toward the full and equal recognition of human dignity. Every year, new speeches and writings help us understand what dignity is—not only what it looks like when dignity is violated but also what it looks like when dignity is honored. In his posthumous essay, Congressman Lewis wrote, "When historians pick up their pens to write the story of the 21st century, let them say that it was your generation who laid down the heavy burdens of hate at last and that peace finally triumphed over violence, aggression and war."</p> <p>The more we talk about human dignity, the better we understand it. And the sooner we can make progress toward a shared vision of peace, freedom, and mutual respect for all. </p>
With just a few strategical tweaks, the Nazis could have won one of World War II's most decisive battles.
- The Battle of Britain is widely recognized as one of the most significant battles that occurred during World War II. It marked the first major victory of the Allied forces and shifted the tide of the war.
- Historians, however, have long debated the deciding factor in the British victory and German defeat.
- A new mathematical model took into account numerous alternative tactics that the German's could have made and found that just two tweaks stood between them and victory over Britain.
Two strategic blunders<p>Now, historians and mathematicians from York St. John University have collaborated to produce <a href="http://www-users.york.ac.uk/~nm15/bootstrapBoB%20AAMS.docx" target="_blank">a statistical model (docx download)</a> capable of calculating what the likely outcomes of the Battle of Britain would have been had the circumstances been different. </p><p>Would the German war effort have fared better had they not bombed Britain at all? What if Hitler had begun his bombing campaign earlier, even by just a few weeks? What if they had focused their targets on RAF airfields for the entire course of the battle? Using a statistical technique called weighted bootstrapping, the researchers studied these and other alternatives.</p><p>"The weighted bootstrap technique allowed us to model alternative campaigns in which the Luftwaffe prolongs or contracts the different phases of the battle and varies its targets," said co-author Dr. Jaime Wood in a <a href="https://www.york.ac.uk/news-and-events/news/2020/research/mathematicians-battle-britain-what-if-scenarios/" target="_blank">statement</a>. Based on the different strategic decisions that the German forces could have made, the researchers' model enabled them to predict the likelihood that the events of a given day of fighting would or would not occur.</p><p>"The Luftwaffe would only have been able to make the necessary bases in France available to launch an air attack on Britain in June at the earliest, so our alternative campaign brings forward the air campaign by three weeks," continued Wood. "We tested the impact of this and the other counterfactuals by varying the probabilities with which we choose individual days."</p><p>Ultimately, two strategic tweaks shifted the odds significantly towards the Germans' favor. Had the German forces started their campaign earlier in the year and had they consistently targeted RAF airfields, an Allied victory would have been extremely unlikely.</p><p>Say the odds of a British victory in the real-world Battle of Britain stood at 50-50 (there's no real way of knowing what the actual odds are, so we'll just have to select an arbitrary figure). If this were the case, changing the start date of the campaign and focusing only on airfields would have reduced British chances at victory to just 10 percent. Even if a British victory stood at 98 percent, these changes would have cut them down to just 34 percent.</p>
A tool for understanding history<p>This technique, said co-author Niall Mackay, "demonstrates just how finely-balanced the outcomes of some of the biggest moments of history were. Even when we use the actual days' events of the battle, make a small change of timing or emphasis to the arrangement of those days and things might have turned out very differently."</p><p>The researchers also claimed that their technique could be applied to other uncertain historical events. "Weighted bootstrapping can provide a natural and intuitive tool for historians to investigate unrealized possibilities, informing historical controversies and debates," said Mackay.</p><p>Using this technique, researchers can evaluate other what-ifs and gain insight into how differently influential events could have turned out if only the slightest things had changed. For now, at least, we can all be thankful that Hitler underestimated Britain's grit.</p>
A new study shows our planet is much closer to the supermassive black hole at the galaxy's center than previously estimated.
Arrows on this map show position and velocity data for the 224 objects utilized to model the Milky Way Galaxy. The solid black lines point to the positions of the spiral arms of the Galaxy. Colors reflect groups of objects that are part of the same arm, while the background is a simulation image.
Apple sold its first iPod in 2001, and six years later it introduced the iPhone, which ushered in a new era of personal technology.