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... this is one of the top three fascinating threads on ARFCOM in 37 months
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Quoted: Lots of pics of an abandoned commie space shuttle: http://ralphmirebs.livejournal.com/219949.html https://img-fotki.yandex.ru/get/5801/46616872.dc/0_cbbe3_39b1c47a_orig.jpg View Quote ... epitome of Soviet era space missions. No grasp on NASA type Systems Engineering. Bash her if you want, but no country performs better aerospace engineering than us |
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That's what makes me think it was amateurs that built this bird. On one craft I worked on we had a timer interrupt perform a reset. If the timer was not reset periodically by the OS it was assumed it was stuck in a loop somewhere and the timer would count down and reset the bird. The communications systems also had a type of interrupt only if there was no communications on the high speed band it assumed a problem and would automatically switch over to the low speed band & antenna and try again. These are very basic ideas when building robotic devices that will operate where nobody can walk over and push a button or pull the battery - maybe Bill should go back to TV and leave the engineering to the engineers. View Quote View All Quotes View All Quotes Quoted:
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I don't understand why these things wouldn't have an automatic reset/reboot built in so that every, say, 30 days the computer does an uncommanded reset. Have it so that an interrupt signal would have to be received from Earth to keep the restart from happening. Everything cool? Great, just send the restart interrupt signal. Can't get a signal? Auto reset proceeds at scheduled time. That's what makes me think it was amateurs that built this bird. On one craft I worked on we had a timer interrupt perform a reset. If the timer was not reset periodically by the OS it was assumed it was stuck in a loop somewhere and the timer would count down and reset the bird. The communications systems also had a type of interrupt only if there was no communications on the high speed band it assumed a problem and would automatically switch over to the low speed band & antenna and try again. These are very basic ideas when building robotic devices that will operate where nobody can walk over and push a button or pull the battery - maybe Bill should go back to TV and leave the engineering to the engineers. The Watchdog Timer idea works, but resetting it from Earth would be a problem as it gets further away, what duration? Tangentially similar to the Mars rover that kept rebooting before new code could be loaded, a tiny time window they had to hit, or it was stuck in a reboot loop. |
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Next time the Moon is out at the same time as the sun look at which direction the light side is facing. I'll give you a hint: it's not towards the sun.
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Next time the Moon is out at the same time as the sun look at which direction the light side is facing. I'll give you a hint: it's not towards the sun. View Quote Do you have a diagram of that? I don't have Stellarium installed on this system, and don't want to wait until the moon and sun are both up. |
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Quoted: Do you have a diagram of that? I don't have Stellarium installed on this system, and don't want to wait until the moon and sun are both up. View Quote View All Quotes View All Quotes Quoted: Quoted: Next time the Moon is out at the same time as the sun look at which direction the light side is facing. I'll give you a hint: it's not towards the sun. Do you have a diagram of that? I don't have Stellarium installed on this system, and don't want to wait until the moon and sun are both up. |
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Quoted: Quoted: Next time the Moon is out at the same time as the sun look at which direction the light side is facing. I'll give you a hint: it's not towards the sun. |
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View Quote Is the point of light to the left of the sun which descends at the same rate a planet? |
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Is the point of light to the left of the sun which descends at the same rate a planet? View Quote View All Quotes View All Quotes Quoted:
Is the point of light to the left of the sun which descends at the same rate a planet? Earth would be my guess. |
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Quoted: Quoted: Is the point of light to the left of the sun which descends at the same rate a planet? Earth would be my guess. |
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Some of the ISS crew have just returned from space. Some pics:
The rocket they took up being rolled out: Snug fit. (These are not the guys on this mission): Lots more pics here |
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View Quote It looks like Pluto isn't perfectly spherical? |
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Quoted: It looks like Pluto isn't perfectly spherical? View Quote View All Quotes View All Quotes |
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It looks like Pluto isn't perfectly spherical? View Quote View All Quotes View All Quotes Neither is Earth |
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Neither is Earth |
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Quoted: Quoted: Neither is Earth |
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just to make sure I understand that smiley... you're saying you knew Earth was an Oblate Spheroid? View Quote View All Quotes View All Quotes Quoted:
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Neither is Earth Who doesn't? In fact, the tallest mountain when measured from the center of the Earth, is in Ecuador. It's over 7,000' taller than Everest despite being only about 20,000' above sea level. Equatorial Bulge FTW. |
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just to make sure I understand that smiley... you're saying you knew Earth was an Oblate Spheroid? View Quote View All Quotes View All Quotes Quoted:
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Neither is Earth Yes. I think I learned that in elementary school (not the term, but that Earth wasn't a sphere). Looking at the Pluto pics, it appears as if a large chunk is missing. You can't really compare that to a squished ball. |
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You can clearly see that the barycenter of pluto and charon is located in empty space: http://i.imgur.com/LgWwoQh.gif View Quote If Pluto is rotating independently and not tidally locked with Charon, might that amount of pull create some internal heat? |
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Quoted: Yes. I think I learned that in elementary school (not the term, but that Earth wasn't a sphere). Looking at the Pluto pics, it appears as if a large chunk is missing. You can't really compare that to a squished ball. View Quote |
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Quoted: If Pluto is rotating independently and not tidally locked with Charon, might that amount of pull create some internal heat? View Quote View All Quotes View All Quotes Quoted: Quoted: You can clearly see that the barycenter of pluto and charon is located in empty space: http://i.imgur.com/LgWwoQh.gif If Pluto is rotating independently and not tidally locked with Charon, might that amount of pull create some internal heat? |
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NASA is now uploading 4k ultra HD video from the ISS.
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NASA is now uploading 4k ultra HD video from the ISS. http://www.blastr.com/2015-6-16/nasa-now-uploading-4k-ultra-hd-video-international-space-station View Quote I want to go to space so bad |
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NASA is now uploading 4k ultra HD video from the ISS. http://www.blastr.com/2015-6-16/nasa-now-uploading-4k-ultra-hd-video-international-space-station I want to go to space so bad I have hoped for as long as I remember, that when we die we get to take a "tour" through the universe on the way to where we are going. There is so, so, so much we will never get to see unless something like that happens. |
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I have hoped for as long as I remember, that when we die we get to take a "tour" through the universe on the way to where we are going. There is so, so, so much we will never get to see unless something like that happens. View Quote View All Quotes View All Quotes Quoted:
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NASA is now uploading 4k ultra HD video from the ISS. http://www.blastr.com/2015-6-16/nasa-now-uploading-4k-ultra-hd-video-international-space-station I want to go to space so bad I have hoped for as long as I remember, that when we die we get to take a "tour" through the universe on the way to where we are going. There is so, so, so much we will never get to see unless something like that happens. +1 i'm way more excited for new horizon's approach to pluto on july 14th than i should be. |
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First color video: http://www.nasa.gov/sites/default/files/styles/full_width/public/thumbnails/image/loop_final.gif?itok=GoSUPT33 View Quote Am I seeing a complete rotation every 6 days? |
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Quoted: Am I seeing a complete rotation every 6 days? View Quote View All Quotes View All Quotes Quoted: Am I seeing a complete rotation every 6 days? |
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This is awesome stuff. Keep it coming!
If you know of a good video that covers wormhole theory, black hole -> pulsar/quasar theories, and relative galactic motions, that would be cool. I like that sort of stuff. Also, a video that covers gravity, and explains if gravity has a speed or if it is instantaneous. I've heard it both ways, heard it settled on "speed of gravity = c", then a few years later as "speed of gravity is spooky action at a distance", then back to having speed.... No perpetual motion/free energy/burning water crap from the whacko area of YouTube, please. |
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Quoted: This is awesome stuff. Keep it coming! If you know of a good video that covers wormhole theory, black hole -> pulsar/quasar theories, and relative galactic motions, that would be cool. I like that sort of stuff. Also, a video that covers gravity, and explains if gravity has a speed or if it is instantaneous. I've heard it both ways, heard it settled on "speed of gravity = c", then a few years later as "speed of gravity is spooky action at a distance", then back to having speed.... No perpetual motion/free energy/burning water crap from the whacko area of YouTube, please. View Quote According to Eisenstein gravity is a result of the warping of space time. While everything in space has to obey the speed limit "C" space itself does not. Then there is a phenomenon yet to be confirmed as far as I'm aware called a gravity wave... those might propagate through space at C... Gravity is still not as well understood as we would like. There are still big questions yet to be definitively answered. |
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Gravity is still not as well understood as we would like. There are still big questions yet to be definitively answered. View Quote That's my interest in the topic. Since college, the "speed of gravity" has changed from infinite to c. Some attempt at a Grand Unified Theory (GUT) that includes gravity requied it to move at a constant speed. That theory fell apart, however. Once we have the GUT, it won't be long before we have anti-gravity vehicles, interstellar travel, and a much more. To be fair, we are finally just figuring out what exactly makes magnets work at the quantum level (quark spin states), even though we've had equations to perfectly model their behavior for a very long time. Therefore I don't expect any huge breakthroughs like warp drives soon. |
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Quoted: This is awesome stuff. Keep it coming! If you know of a good video that covers wormhole theory, black hole -> pulsar/quasar theories, and relative galactic motions, that would be cool. I like that sort of stuff. Also, a video that covers gravity, and explains if gravity has a speed or if it is instantaneous. I've heard it both ways, heard it settled on "speed of gravity = c", then a few years later as "speed of gravity is spooky action at a distance", then back to having speed.... No perpetual motion/free energy/burning water crap from the whacko area of YouTube, please. View Quote This is the cosmic microwave background. The hot spots are clumps of mass in the early universe. The size that a clump can be in this picture is governed by the speed of light. This is because the universe was so young at the point this picture was taken that gravity hadn't had enough time to reach out and pull in matter from any farther away. Some of it is covered in this vid: |
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Sidenote:
We are in a K6 rated Geomagnetic storm tonight (and yesterday). So Get outside tonight for the Aurora Borealis if you live above about 43°N -ish. More southern areas can also see it if it's pitch black and they look close. |
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Quoted: Sidenote: We are in a K6 rated Geomagnetic storm tonight (and yesterday). So Get outside tonight for the Aurora Borealis if you live above about 43°N -ish. More southern areas can also see it if it's pitch black and they look close. View Quote |
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