“We are much closer today to being able to send humans to Mars than we were to being able to send men to the moon in 1961, and we were there eight years later. Given the will, we could have humans on Mars within a decade.” –Robert Zubrin
This is what we can accomplish when we invest in something big.
I’m not talking about the Olympics, of course. I’m talking about investing in science, in exploration, in robotics, in engineering, in technology, and in humanity, and what can we accomplish?
For just the seventh time in history, we’ve successfully landed a spacecraft on Mars. This time, however, is different.
This time, we landed the largest, heaviest, most advanced robotic science laboratory ever constructed. Or, I should say, we got it to land itself.
After a journey of more than 350 million miles through space — from Earth through interplanetary space, all the way to Mars — Mars Science Laboratory had to hit an entry window towards Mars that was less than 15 square miles in size. By time it was set to arrive at Mars, the Red Planet was more than 150,000,000 kilometers away from Earth, meaning that it takes light (and all forms of communication) more than 15 minutes to travel from Mars Science Laboratory to Earth and back to the spacecraft again.
This time delay is so large that we couldn’t simply send commands to this spacecraft and tell it what to do; we need to empower it to make intelligent decisions on its own! And this was especially challenging because of how ridiculously powerful and awesome this new science laboratory is.
Mars Science Laboratory, shown all the way at the right, not only dwarfs all other laboratories ever sent to Mars in terms of size (it weighs nearly a tonne and is the size of a small SUV), but also in terms of technological power. With 17 cameras on board, a specially designed martian weather station, and a sample analysis kit capable of detecting organics (among other things), this spacecraft has a total of 10 major science instruments.
And, as you can imagine, it didn’t come cheap: all told, it cost $2.5 billion dollars to make this science laboratory, complete with the rover, launch, and landing systems. (For those of you wondering, Curiosity is the name of the rover, while Mars Science Laboratory is the name of the NASA mission.) This was how much it cost to do it right, which is the only way to do it if you want to land on Mars, considering the failure rate.
Because not only is it difficult to get there and land successfully under the best of circumstances, we’ve never landed anything on another world that was this combination of large, heavy, and fragile, which means that a whole new landing system needed to be designed. For $2.5 billion, you only get one shot at getting it right.
And the landing site in Gale Crater — 96 km across in its entirety — required an unprecedented precision. In order to land on Mars, Curiosity could be moving no faster than just a couple of miles-per-hour upon touchdown, which would make it the slowest, easiest landing ever performed on another world, and it needed to be performed with (by far) the heaviest device ever attempted to land on another world.
And there were plenty of worries. First off, the journey from the edge of Mars’ atmosphere to touchdown on the surface took seven minutes, meaning that by time the device is a few thousand kilometers above the surface of Mars, it’s on its own, as we can no longer send it a signal to correct its course. So it needs to be able to do literally everything on its own.
It needs to successfully hit the atmosphere at the correct angle so that the heat shield can absorb the intense energy of decelerating from 13,000 miles-per-hour down to about Mach 2. If even a small fraction of that heat made it through to the instruments, Curiosity would be ruined.
Then, the parachute needed to deploy properly, which means at the right time and speed to slow it down to a reasonable (about 180 miles-per-hour) by time it’s ready to jettison its heat shield.
This was a rousing success, and was even imaged (above) by the passing Mars HiRISE mission! This itself is very dangerous, because unlike the Moon, Mars has a significant atmosphere and rapid winds that can easily accelerate spacecraft to speeds over 100 km/hour; an impact at that speed would doubtlessly mean the demise of Curiosity.
In the past, we had used giant airbags to protect rovers from these speeds upon impact, a technology with an incredible track record of success that included Pathfinder, Spirit, and Opportunity.
But the weight of the Curiosity rover meant that this method would be inadequate, and that a new, never-before-attempted landing technique would be required. As about 50% of all attempted Mars landings have failed, this was where the real terror kicked in. Because now, we need to go from falling at about 180 miles-per-hour not just vertically, but also with significant horizontal speed, and slow down to make a landing that’s no harsher than dropping an egg from a height of about 6 inches (or 15 centimeters).
How was this to happen?
A brand new descent system, outfitted with eight retro-rockets, would bring the entire system to a virtual standstill just a few dozen feet above the martian surface, where it would then lower the rover down onto the ground ever-so-delicately.
This was the most critical stage, and meant the difference between two-to-six years of unprecedented science and a very public, $2.5 billion failure.
After maybe two minutes of total silence, the critical signal arrived.
Curiosity had landed, successfully! Almost immediately, the rover set out to do its pre-programmed photography sequence, snapping images of where it landed. Unsurprisingly, the landing (and the retro-rockets) had kicked up a large amount of dust, but one spectacularly impressive picture stood out.
More photos (including real-color images) are undoubtedly forthcoming, so sit tight (and follow along as the news comes out in real-time), but we know already that this landing means two outstanding things.
First, we made it! We are inside Gale Crater — where we are almost certain a liquid lake once existed — and ready to investigate the soil beneath our wheels, the atmosphere and weather above us, and the cosmic rays plunging all the way through the atmosphere. It looks like it’s in fantastic shape to meet all six of its science goals, including learning about radiation levels that humans will be exposed to.
But second, it means that if we can land something this complex and heavy this delicately, we can do this.
We can send a manned mission to Mars. We’ve already learned about radiation during the 9-month journey to the red planet, and we’ve successfully developed and used the technology necessary to make a heavy, controlled landing on Mars.
All that we need to make this a reality is to invest in the people who can make it happen. We’ve got the know-how, we’ve got the experience, we’ve got the astronauts and we’ve got the plans; all we need is the decision that this is worth investing in and we can be on Mars within a decade. After all, we’ve come so far already.
I can’t wait to see what Curiosity learns, and I am so hopeful that this success means that exploring the Universe won’t mean quibbling over budgetary table scraps anymore; there’s a feast to be had if only we’re willing to make the investment of planting the seeds. From last year to this, NASA’s budget was just cut by another 2%, taking it down to about 18 billion dollars annually for everything: astronauts, launches, Earth-monitoring satellites, employees, contracts, telescopes and facilities, and all of NASA science.
But if we can achieve all of this with so little, imagine what we could do if we actually invested in science, in exploration, in robotics, in engineering, in technology, and in humanity.
Here’s looking forward to an amazing mission, sure to be full of unprecedented discoveries. I’m so excited about it that — once again — I’m headed out tonight onto my local news (KGW NewsChannel 8), talking about the amazing landing of Curiosity on Mars and what it means for all of us.