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2003 SD220: Asteroid to flyby Earth on Christmas Eve in first of five encounters
www.ibtimes.co.uk ^ | December 17, 2015 12:13 GMT | By Hannah Osborne

Posted on 12/17/2015 12:46:11 PM PST by Red Badger

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To: Ancesthntr
The Yarkovsky effect is a force acting on a rotating body in space caused by the anisotropic emission of thermal photons, which carry momentum.

The effect appears to be similar to the 'solar sail', where "pressure" from sunlight pushes a spacecraft.

From wikipedia...

Solar sails (also called light sails or photon sails) are a form of spacecraft propulsion using the radiation pressure (also called solar pressure) from stars to push large ultra-thin mirrors to high speeds. Light sails could also be driven by energy beams to extend their range of operations, which is strictly beam sailing rather than solar sailing.

Solar sail craft offer the possibility of low-cost operations combined with long operating lifetimes. Since they have few moving parts and use no propellant, they can potentially be used numerous times for delivery of payloads.

Solar sails use a phenomenon that has a proven, measured effect on spacecraft. Solar pressure affects all spacecraft, whether in interplanetary space or in orbit around a planet or small body. A typical spacecraft going to Mars, for example, will be displaced by thousands of kilometres by solar pressure, so the effects must be accounted for in trajectory planning, which has been done since the time of the earliest interplanetary spacecraft of the 1960s. Solar pressure also affects the attitude of a craft, a factor that must be included in spacecraft design.[1]

The total force exerted on an 800 by 800 meter solar sail, for example, is about 5 newtons (1.1 lbf) at Earth's distance from the Sun,[2] making it a low-thrust propulsion system, similar to spacecraft propelled by electric engines."

21 posted on 12/17/2015 2:03:45 PM PST by ETL (Ted Cruz 2016!! -- For a better, safer America)
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To: Red Badger
Read Robert Heinlein’s “Farnham’s Freehold”. It has everything you need to know...........................

Some of us have already read it. Hint: Time travelers find that Islamic Masters have enslaved our progeny.

22 posted on 12/17/2015 2:04:34 PM PST by higgmeister ( In the Shadow of The Big Chicken!)
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To: higgmeister
Like I said, it has EVERYTHING you NEED to know.............................
23 posted on 12/17/2015 2:07:42 PM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: Boogieman; LambSlave

Pertty much!...................


24 posted on 12/17/2015 2:09:00 PM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: Ancesthntr

Well, the output of the sun is not constant, so we have a situation like Global Warming, IOW, they don’t know..........................


25 posted on 12/17/2015 2:10:04 PM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: Paladin2

I was thinking of that while in Wal-Mart. Just think of how many drones we will have around in a few years. Better make that blind a bunker.


26 posted on 12/17/2015 2:16:06 PM PST by mcshot (The "Greatest Generation" would never have allowed the trashing of our Republic.)
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To: Red Badger; 75thOVI; Abathar; agrace; aimhigh; Alice in Wonderland; AndrewC; aragorn; ...

Thanks Red Badger.

27 posted on 12/17/2015 2:21:20 PM PST by SunkenCiv (Here's to the day the forensics people scrape what's left of Putin off the ceiling of his limo.)
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To: mcshot

Not only that, I need to start working on my Tractor Beam....


28 posted on 12/17/2015 2:23:23 PM PST by Paladin2 (my non-desktop devices are no longer allowed to try to fix speling and punctuation, nor my gran-mah.)
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To: SunkenCiv

I bet they wouldn’t tell us if it was gonna hit........................


29 posted on 12/17/2015 2:32:59 PM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: ETL

“1.36 AU, or 1.36 x 92.5 million miles = 125 million miles”

Too many decimals! Make it an even 9 million furlongs.


30 posted on 12/17/2015 7:33:45 PM PST by Pete from Shawnee Mission
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To: Red Badger
The Yarkovsky effect is a force acting on a rotating body in space caused by the anisotropic emission of thermal photons, which carry momentum. It is usually considered in relation to meteoroids or small asteroids (about 10 cm to 10 km in diameter), as its influence is most significant for these bodies.

Yes of course! Who doesn't know THAT, pfft...(makes a "sure I knew that" face)

31 posted on 12/18/2015 7:03:12 AM PST by FourtySeven (47)
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To: Boogieman

Oh!! You WILL cut that hair son! What are you a hippie??

< /childhood memories >


32 posted on 12/18/2015 7:04:45 AM PST by FourtySeven (47)
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To: ETL; Red Badger

It’s that danged Yarkovsky effect! It’ll get you every time. Must be a Soviet trick, all part of their plan to steal our vital bodily fluids.


33 posted on 12/18/2015 7:06:37 AM PST by FourtySeven (47)
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To: FourtySeven

To put it in layman’s terms, The smaller the body the larger the effect of photons hitting it. But the sun’s output is not constant so it will take many years of measurements to average it out to determine the orbit accurately..............


34 posted on 12/18/2015 7:12:35 AM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: Red Badger
Like I said, it has EVERYTHING you NEED to know.............................

Yes everything we needed to know.

35 posted on 12/20/2015 4:46:03 PM PST by higgmeister ( In the Shadow of The Big Chicken!)
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