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Beware the Rings of Pluto
Hugh Pickens writes "The Christian Science Monitor reports that scientists are planning a new route for NASA's New Horizons space probe as it approaches a potentially perilous path toward Pluto through a possible set of rings that may create dangerous debris zones for the NASA spacecraft. New Horizons is currently about 1,000 days away and 730 million miles from closest approach to Pluto but given that New Horizons is currently zooming away from the sun at more than 33,500 mph, 'a collision with a single pebble, or even a millimeter-sized grain, could cripple or destroy New Horizons,' says project scientist Hal Weaver. 'We need to steer clear of any debris zones around Pluto.' Researchers are making plans to avoid these hazards if New Horizons needs to. 'We are now exploring nine other options, "bail-out trajectories,"' says principal investigator Alan Stern. New Horizon's current plan would take it about halfway between Pluto and the orbit of its largest moon, Charon. Four of the bail-out trajectories would still take the spacecraft between Pluto and Charon's orbit. The other alternatives would take New Horizons much further away from Pluto, past the orbits of its known moons. 'If you fly twice as far away, your camera does half as well; if it's 10 times as far, it does one-tenth as well,' says Stern. 'Still, half a loaf is better than no loaf. Sending New Horizons on a suicide mission does no one any good. We're very much of the mind to accomplish as much as we can, and not losing it all recklessly. Better to turn an A+ to an A- than get an F by overreaching.'"
Potentially perilous Pluto path? Perfectly petrifyingly perigee perturbation!
when I was young, only planets were allowed to have rings!
I thought if you fly twice as far, your camera will work 1/4 as well, not 1/2.
I blame Neil Degrasse Tyson for all this.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Having or not having a moon isn't part of the definition of a planet.
"(a) is in orbit around the Sun,
(b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and
(c) has cleared the neighbourhood around its orbit." [http://en.wikipedia.org/wiki/Planet#2006_definition]
Pluto meets A,B and not C.
C is there to discredit large asteroids in the asteroid belt.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Now even our spacecraft are getting bailouts!
The center of gravity of Pluto and Charon is not inside of Pluto's radius.
I love Jesus, except for his foreign policy.
So since most of the cost in any given NASA science project is in the hardware research and engineering not the construction, neither launch nor operation side why they hell aren't they making use of economies of scale? Stop building only one of something (well technically two, the "on earth version" and the "mission" version). Spread the risk out by flying in multiples. It would be unfortunate if one of them hits a "pebble" but the science returned would be magnitudes better because they're able to take advantage of opportunities that wouldn't be possible due to risk aversion. Take it a step further and make use of the same hardware R&D for multiple missions. Engineer a few platforms that are robust, and reasonably customizable. Each platform with a particular type of mission in mind. Put a Curiosity on Europa, Titan, and/or Ariel. Get an MRO around Ganymede, etc.. You don't need 7 minutes of terror if the hardware you spent more than $2B developing has already been flown and proven on other missions. You wouldn't be (as) scared to death that Congress will cut your funds because you're making good, efficient use of the R&D money. "Yes senator, that $2B from Congress has given us a platform we've reused on 10 missions now."
Two of my imaginary friends reproduced once
I thought all christians believed the earth was flat, the earth is the center of the solar system and the universe ended at the barrier around our solar system..
That's because you're a bigot.
"(a) is in orbit around the Sun,
(b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and
(c) has cleared the neighbourhood around its orbit." [http://en.wikipedia.org/wiki/Planet#2006_definition]
Pluto meets A,B and not C.
Neither has Jupiter.
Free Martian Whores!
The gravitational perturbations would, more than likely, cause the moon's moon to be unstable. Eventually, it (the moon's moon) would either crash into the planet or the moon, or be ejected from the system entirely. However, for the short term, it is entirely possible. Our Moon has quite a number of satellites orbitting it; all artificial, of course.
When our name is on the back of your car, we're behind you all the way!
You don't really get much improvement in per-unit cost by building 10 of something vs 2. The biggest factor in the cost even with just the first couple isn't the engineering but the testing and qualification. Most of that has to be repeated for every unit you build until you are creating enough to have confidence in the past performance and to fall back to statistical testing, or at least are building enough for automating that work to be economical. But you would need to be creating several dozen of them for that to kick in. Furthermore, construction is more expensive that you are allowing for at those low quantities since it's all is done by hand, by highly skilled labor. That won't drop by much until you get into mass-manufacturing quantities, hundreds at least.
So you would get minor savings, and at the loss of a huge amount of science. There is a reason that each of these probes is wildly different, and that is because the have wildly varying requirements. There is no one-size fits all suite of sensors. They will want different spectral ranges, different optics setups (detailed, narrow FOV vs wide coverage), different transmitter requirements (Horizon has much farther to transmit than MRO), all of which drives different battery requirements.
Finally, the point of science is to keep learning; to keep pushing things forward. You do that by sending probes with improved and/or different capabilities, not just more of the same. Sure we could have sent 3 more MERs (Spirit/Opportunity) for the cost of Curiosity, but we wouldn't have learned as much as Curiosity will be able to tell us.
See Ida/Dactyl.
Stick Men
Trojans don't count in the same way that moons don't count. Basically, the definition of "cleared the neighborhood" means that anything left is dominated by the gravitational influence of the planet. Moons orbit the planet, Trojans orbit the Lagrange points.
Another similar class of objects are those in orbital resonance with the planet. The Pluto/Neptune system, for example. Or Cruithne/Earth. The planet's gravity dominates in each case, so we're OK there.
The term "cleared the neighborhood" is unfortunately misleading. And purposefully vague, I always thought. When does the neighborhood become cleared? There's a lot of asteroids in our near neighborhood (which result in rather significant accretion events, so to speak).
You can blame that one on the drama peddlers. Interviewing rational Christians would be boring. They sell a lot more newspapers by seeking out the kooks and covering them. They might hold a book burning in which they throw scientific textbooks about evolution into the flames. Makes for great copy.
Intellectual Property is a monopolistic, selfish, and defective concept. It is "tyranny over the mind of man"
Yes, but leaders of rational denominations should NOT stay silent. Otherwise, their organization risks being painted and tainted by the same brush. Speak up against the BS or risk owning it!
Table-ized A.I.