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Carlos Entrena, one of the bright young minds in aerospace, asked a fair question last week in the wake of the Juno mission's successful insertion into orbit around Jupiter: "So why is a spacecraft doing a pre-planned burn a big deal again?" He was right, it did seem a relatively straightforward maneuver.
Another young scientist, Christopher Stelter, offered a series of answers that put the Juno spacecraft's 35-minute engine burn into perspective. Among the reasons, he said, was that, "Most burns a spacecraft does are not critical. If there's a glitch, you can try again later. Not this time. And it's a very long burn."
This exchange captured my attention because NASA in recent years has made the extremely difficult—flying robotic probes throughout the Solar System—look easy. The agency's record of achievement appears more impressive still when compared to other space agencies. In reality, no other country or space agency can really be considered NASA's peer, especially when it comes to Mars and beyond. (Admittedly, the Soviet Union does have a better record with Venus).
Consider Mars: in the 1960s the Soviet Union sent eight probes to Mars. All failed, and most were lost even before reaching Earth orbit. By contrast, three of NASA's first four missions to Mars were successful, including Mariner 4, which returned the first close-up images of the Red Planet in 1965.
Then there are the Martian landers. Eight of NASA's nine missions to the surface of Mars have been successful, with only its Mars Polar Lander failing to safely reach the surface. By contrast, four of five Soviet landers failed to reach Mars safely, and the one that did, Mars 3 in 1971, survived for only about 15 seconds. No other nation or agency has landed on Mars. Since NASA's last high-profile failure in Solar System exploration, the polar lander in 1999, Japan, China, Russia, and the United Kingdom have all lost various orbiters and landers sent to the Martian system. (In the meantime NASA put Spirit, Opportunity, Phoenix, and Curiosity on the Martian surface).
The record is more stark for Jupiter and beyond. The Soviet Union and Russia have never flown beyond Mars. The European Space Agency has participated in two NASA missions that have gone beyond the asteroid belt. The first, Ulysses, made two distant flybys of Jupiter during a mission that focused primarily on observing the Sun. NASA managed development of the second mission, Cassini, which has had a spectacular run of observing the Saturn system over the last decade. As part of that mission, the European Space Agency's Titan lander was partially successful.
And that's it for the rest of the world. Meanwhile NASA has explored the outer Solar System with Pioneer 10 and 11, Voyager 1 and 2, the Galileo and now Juno missions to the Jupiter system, and New Horizons to Pluto and beyond. It is amazing to contemplate the fact that every single probe NASA has sent into the outer Solar System has been a success. In this, NASA has a perfect record with missions no other space agency has even sought to attempt.
This is testament to NASA and its planetary science division, led by Jim Green since 2006, and a host of other visionaries before him. It is due to the fantastic work by engineers and scientists at NASA's Jet Propulsion Laboratory in California and NASA centers elsewhere across the country. And finally, it is due to Washington DC, which has recognized the value of exploring our Solar System and invested long-term in these missions.
And about those routine burns, like the one made by Juno? Back in 2010 Japan's Akatsuki spacecraft was due to make a 12-minute burn to nudge itself into orbit around Venus. Instead, the engine fired for less than three minutes, likely due to salt deposits jamming a valve between the helium pressurization tank and the fuel tank. Five years later, after spiraling around the inner Solar System, the spacecraft came close enough to Venus to try again. Using the vehicle's less powerful attitude control thrusters, Akatsuki reached a much higher orbit around Venus than originally planned. Some science has since been done.
Akatsuki, once again, demonstrated that there is nothing routine with deep space missions. Therefore when following the progress of missions such as Juno, we should not take NASA's successful track record for granted. Rather, we should celebrate it.
http://arstechnica.com/science/2016...rogram-is-just-about-the-greatest-thing-ever/
Another young scientist, Christopher Stelter, offered a series of answers that put the Juno spacecraft's 35-minute engine burn into perspective. Among the reasons, he said, was that, "Most burns a spacecraft does are not critical. If there's a glitch, you can try again later. Not this time. And it's a very long burn."
This exchange captured my attention because NASA in recent years has made the extremely difficult—flying robotic probes throughout the Solar System—look easy. The agency's record of achievement appears more impressive still when compared to other space agencies. In reality, no other country or space agency can really be considered NASA's peer, especially when it comes to Mars and beyond. (Admittedly, the Soviet Union does have a better record with Venus).
Consider Mars: in the 1960s the Soviet Union sent eight probes to Mars. All failed, and most were lost even before reaching Earth orbit. By contrast, three of NASA's first four missions to Mars were successful, including Mariner 4, which returned the first close-up images of the Red Planet in 1965.
Then there are the Martian landers. Eight of NASA's nine missions to the surface of Mars have been successful, with only its Mars Polar Lander failing to safely reach the surface. By contrast, four of five Soviet landers failed to reach Mars safely, and the one that did, Mars 3 in 1971, survived for only about 15 seconds. No other nation or agency has landed on Mars. Since NASA's last high-profile failure in Solar System exploration, the polar lander in 1999, Japan, China, Russia, and the United Kingdom have all lost various orbiters and landers sent to the Martian system. (In the meantime NASA put Spirit, Opportunity, Phoenix, and Curiosity on the Martian surface).
The record is more stark for Jupiter and beyond. The Soviet Union and Russia have never flown beyond Mars. The European Space Agency has participated in two NASA missions that have gone beyond the asteroid belt. The first, Ulysses, made two distant flybys of Jupiter during a mission that focused primarily on observing the Sun. NASA managed development of the second mission, Cassini, which has had a spectacular run of observing the Saturn system over the last decade. As part of that mission, the European Space Agency's Titan lander was partially successful.
And that's it for the rest of the world. Meanwhile NASA has explored the outer Solar System with Pioneer 10 and 11, Voyager 1 and 2, the Galileo and now Juno missions to the Jupiter system, and New Horizons to Pluto and beyond. It is amazing to contemplate the fact that every single probe NASA has sent into the outer Solar System has been a success. In this, NASA has a perfect record with missions no other space agency has even sought to attempt.
This is testament to NASA and its planetary science division, led by Jim Green since 2006, and a host of other visionaries before him. It is due to the fantastic work by engineers and scientists at NASA's Jet Propulsion Laboratory in California and NASA centers elsewhere across the country. And finally, it is due to Washington DC, which has recognized the value of exploring our Solar System and invested long-term in these missions.
And about those routine burns, like the one made by Juno? Back in 2010 Japan's Akatsuki spacecraft was due to make a 12-minute burn to nudge itself into orbit around Venus. Instead, the engine fired for less than three minutes, likely due to salt deposits jamming a valve between the helium pressurization tank and the fuel tank. Five years later, after spiraling around the inner Solar System, the spacecraft came close enough to Venus to try again. Using the vehicle's less powerful attitude control thrusters, Akatsuki reached a much higher orbit around Venus than originally planned. Some science has since been done.
Akatsuki, once again, demonstrated that there is nothing routine with deep space missions. Therefore when following the progress of missions such as Juno, we should not take NASA's successful track record for granted. Rather, we should celebrate it.
http://arstechnica.com/science/2016...rogram-is-just-about-the-greatest-thing-ever/