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Striking


Subdeacon Joe

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http://digg.com/2019/super-blood-wolf-moon-meteor-strike?fbclid=IwAR3PNhadH8zsA_-Q9gJu_bRsuBgyICNtLjO2_YJ-mVu_k-wqNfZVOsPERXo

 

Observers who closely watched the Super Blood Wolf Moon eclipse over the weekend spotted an extra bonus: a meteoroid flying into the surface of the moon, mid-eclipse. 

You can see the apparent strike at the 2:11:00 mark in the video, just left of center on the bottom curve of the Moon:
 

 

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9 minutes ago, Forty Rod SASS 3935 said:

The moon has no atmosphere.  What would cause it to flash or flame without oxygen.

 

Give me another solution.  Do meteors et al have an on-board source of oxygen?

 

The impact strikes a Big spark.

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I was too dang tired to stay up. I had run a plow truck all weekend and was pretty tuckered out. The sky was clear as can be for it though.

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18 minutes ago, Forty Rod SASS 3935 said:

But without oxygen there wouldn't be a visible flash.

 

https://physics.stackexchange.com/questions/449571/impact-flash-in-vacuum

Quote

An impactor of mass mm moving at speed vv will have kinetic energy E0=(1/2)mv2E0=(1/2)mv2, which will be significant for hypervelocity impacts. When it hits something inelastically this gets converted into kinetic energy of ejected fragments, work in deforming the target, and through this heating. This heating will make the hot material radiate blackbody radiation - this is what produces the flash.

The problem is that the exact distribution of energy. Some of it will go into a hot spot or ball of plasma shining, but the amount is going to depend on how the impact happens.

If we just assume a fraction ηη ends up as heating a plasma ball of radius rr it will have temperature T=ηE0/(4π/3)r3CT=ηE0/(4π/3)r3C where CC is the volumetric heat capacity of the plasma. If it loses energy as blackbody radiation from a hemisphere as E=(2πr2)σ(E/(4π/3)r3C)4=(27/128π3C4)σE4/r10E′=−(2πr2)σ(E/(4π/3)r3C)4=−(27/128π3C4)σE4/r10, starting out as E=ηE0E=ηE0. The energy and brightness declines as Et1/3E∝t−1/3. Note the extreme dependence on rr; this is yet another reason it is hard to give a reasonable answer, since in practice rr (and CC) will change fast over time.

To sum up, it all depends on complex deformation, fluid and plasma dynamics during the impact.

 

 

http://adsabs.harvard.edu/abs/2015AGUFM.P53C2131R

 

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Abstract

Hypervelocity impacts frequently generate an observable "flash" of light with two components: a short-duration spike due to emissions from vaporized material, and a long-duration peak due to thermal emissions from expanding hot debris. The intensity and duration of these peaks depend on the impact velocity, angle, and the target and projectile mass and composition. Thus remote sensing measurements of planetary impact flashes have the potential to constrain the properties of impacting meteors and improve our understanding of impact flux and cratering processes. Interpreting impact flash measurements requires a thorough understanding of how flash characteristics correlate with impact conditions. Because planetary-scale impacts cannot be replicated in the laboratory, numerical simulations are needed to provide this insight for the solar system. Computational hydrocodes can produce detailed simulations of the impact process, but they lack the radiation physics required to model the optical flash. The Johns Hopkins University Applied Physics Laboratory (APL) developed a model to calculate the optical signature from the hot debris cloud produced by an impact. While the phenomenology of the optical signature is understood, the details required to accurately model it are complicated by uncertainties in material and optical properties and the simplifications required to numerically model radiation from large-scale impacts. Comparisons with laboratory impact experiments allow us to validate our approach and to draw insight regarding processes that occur at all scales in impact events, such as melt generation. We used Sandia National Lab's CTH shock physics hydrocode along with the optical signature model developed at APL to compare with a series of laboratory experiments conducted at the NASA Ames Vertical Gun Range. The experiments used Pyrex projectiles to impact pumice powder targets with velocities ranging from 1 to 6 km/s at angles of 30 and 90 degrees with respect to horizontal. High-speed radiometer measurements were made of the time-dependent impact flash at wavelengths of 350-1100 nm. We will present comparisons between these measurements and the output of APL's model. The results of this validation allow us to determine basic relationships between observed optical signatures and impact conditions.

 

Release enough energy fast enough and you get a flash, with or without oxygen.

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I give up, I've watched the dang thing at least a half dozen times and haven't seen a thing! I've been looking at the bottom edge just left of center and nothing.

 

4T, at meteoric speeds wouldn't the heat of impact throw out white hot rock and debris?

 

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WOW!  A college level class in less than three minutes.

 

And just when I thought I couldn't learn anything new, too.

 

Now that I know it...or a tiny bit about it, I have no idea what to do with all my new smarts.

 

You gotta be quick, Clay.  It's well under a second in duration and it's is very small.

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On ‎1‎/‎23‎/‎2019 at 8:36 PM, Forty Rod SASS 3935 said:

The moon has no atmosphere.  What would cause it to flash or flame without oxygen.

 

Give me another solution.  Do meteors et al have an on-board source of oxygen?

Maybe. Or it could have an alien spacecraft with oxygens and a hot exhaust pipe. 

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23 minutes ago, Sixgun Sheridan said:

Of course you can have explosions and fireballs in space. Didn't you watch Star Wars?

 

;)

And all sorts of noises...

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