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Japanese Space Probe Akatsuki Enters Orbit Around Venus Five Years Late (space.com)
MarkWhittington writes: On May 17, 2010, the Japanese Aerospace Exploration Agency Venus Climate Orbiter probe or as it is now called Akatsuki lifted off from the Tanegashima Space Center. It was supposed to enter orbit around Venus on December 6, 2010. However, due to a failure in the probe's orbital maneuvering thruster, Akatsuki did not enter Venus orbit and went into orbit around the sun instead. According to a story on Space.com, just about five years to the day of the failure, Akatsuki assumed an orbit around the second planet from the sun. Japanese scientists will determine what sort of orbit that is in a couple of days and, hopefully, begin the probe's science mission.
Must be nice to be able to show up five years late and still have a job.
The impressive thing here is that the thruster is still non-operational, so it wasn't just a matter of waiting 5 years to try again. Instead they're using the RCS system, a low-efficiency thruster which was only meant for steering, to perform orbital injection. Reportedly, this is the first time that's been done for a planetary transfer, and should hopefully let them salvage the science mission which was initially thought to be lost (remains to be seen if the science equipment is still working).
The designs of these devices are not that trivial. They require a power source with most space craft it is either solar or nuclear powered. The solar cells are expensive and the nuclear devices are more even expensive. The cameras and sensors are expensive as well. Also these devices require rad-hardened materials which are not easy to come by as well.
And all of this is forgetting about the cost of actually getting the devices into space to begin with.
Duplication isn't trivial for most devices, but if you are going to make a billion of them. It makes sense to set up a system that produces these rapidly and then duplication becomes trivial after setting up the system. Sending 2-5 items into space isn't worth setting up the type of system which makes these thing trivial as well.
US probes got much more reliable over time.
A big part of the cost is the still the launch vehicle and fuel. It may be that probes are now considered reliable enough that the cost of a duplicate launch is not worth it.
Since the 80's, US probes are roughly 90% successful (excluding annoying non-show-stopper glitches) such that a duplicate launch may not be economical.
Japan may be in a different boat, though. They are still in the learning stage similar to the US in the 60's. Plus, if you duplicate probes, you also duplicate design flaws.
One of the lessons Japan should be learning is to design the probe flexible and with enough spare fuel for contingencies. Their missions seem to not work right on the first try such that being able to try again during the mission could be really helpful. For example, if you design an asteroid sampling mission, allow it to be able to try to grab a sample multiple times, and with feedback sensors to learn from each try.
It seems nations get overzealous with their early missions. For example, one of Russia's early 70's Mars landers had little rover. If they had instead focused on reliability, they may have had the first (undisputed) successful Mars landing. They put in too many bells and whistles.
The US also did such with the Ranger program of the early 60's. They kept failing, and they eventually simplified and stripped every scientific instrument off of the probes except the camera systems. Until you perfect the art, K.I.S.S.
Table-ized A.I.
Actually, the Phoenix Mars Lander was built in part from duplicate spare parts from the failed Mars Polar Lander, plus parts from a cancelled mission called "Mars 2001 Surveyor". NASA does reuse stuff.
Table-ized A.I.
Seriously? Your explanation for why something is difficult in real life is that it is difficult in some obscure game?
Does this logic work in the other direction? Would it be as easy to fly, reload weapons, encounter aliens, kill people, steal cars, etc. as some other games make it appear?
In Soviet Washington the swamp drains you.
some obscure game
Maybe you should worry more about your continued possession of a nerd card, rather than community organization in Chicago (your sig). This is a Slashdot space article FFS!
Akatsuki carries 68 fan-made images of Japanese crowdsourced digital pop star Hatsune Miku, etched onto three aluminium plates. I suppose this makes Miku the solar system's first interplanetary celebrity. (Also last year, a Miku music video was beamed into deep space by the European Space Agency as part of its "Wake up, Rosetta!" campaign).
I believe the only other pop music purposefully represented in deep space, is the Chuck Berry song Johnny B. Goode, which is on NASA's Golden Records carried by the two Voyager probes.
They can do this attempt because when the original orbit insertion failed, Akatsuki entered a heliocentric orbit in an 8:9 orbital resonance with Venus, making sure it'd meet up with Venus eventually. I haven't been able to find if that was a happy coincidence or if the initial approach to Venus was designed for this contingency.