(meteorobs) Perseid pic from space

[Bill Cooke]

Wayne,

You are roughly correct on the spatial density. However, it is the flux (= spatial density x speed) which is the risk driver, not the density. In the case of this year's Perseid peak, radar indicates a flux of ~5.5e-3 per square kilometer per hour for particles greater than 0.1 mm in size.

Contrast this to the ISS flux from orbital debris with the same damage potential, which is 0.75 per square kilometer per hour. This is a factor of a hundred or so, but certainly not many orders of magnitude. It also illustrates that the sporadic meteoroid background, which has a flux of about 0.14 per square kilometer per hour to this energy threshold, is much more of a hazard than your standard meteor shower.

It is important to neither overestimate or underestimate the meteoroid risk. Both attitudes have caused issues in the past.

Bill Cooke
Lead, NASA Meteoroid Environments Office
Marshall Space Flight Center

Office: (256) 544-9136
Fax: (256) 544-0242
William.J.Cooke at nasa.gov

On Aug 16, 2011, at 10:39 PM, Wayne Hally wrote:

> It’s not a meteor storm, it’s a shower.
>  
> The particle density during the peak may have been as high as 62 per billion cubic kilometers. That includes objects the size of smoke particles.
>  
> The risk from satellite debris is far higher than that of the Perseids for the ISS, by many orders of magnitude.
>  
> From: meteorobs-bounces at meteorobs.org [mailto:meteorobs-bounces at meteorobs.org] On Behalf Of Lawrence D. Lopez
> Sent: Tuesday, August 16, 2011 10:56 PM
> To: Meteor science and meteor observing
> Subject: Re: (meteorobs) Perseid pic from space
>  
> I can't stand it.
> Have you critically thought about this.
> 
> Space station
> Meteor storm.
> Looks cool.
> What's that hissing sound.
> 
> I guess I'm a worrier.
> 
> 
> 
>  
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