[AZ-Observing] Re: Deep Impact

I forgot to add the speed of light. Assuming the below, although in 30 
minutes it would subtend an angle of 0.47 arc minutes, it takes about 7 
and a half minutes for the sunlight to reach it, and 7 and a half to be 
reflected back. So add 15 minutes to the 30 - still above the horizon, I 
believe.
Stan

Stanley A. Gorodenski wrote:

>My own thought on this is that any increase in brightness will be the 
>result of reflected sunlight from ejecta. The impactor will be traveling 
>at 6.3 mi/sec. If it is assumed the ejecta will travel equally as fast 
>(for every action there is an opposite and equal reaction), then in one 
>minute the ejecta will have traveled 378 miles. In 30 minutes, still 
>above the horizon, it will have traveled 11,340 miles. I believe Earth 
>is about 83,000,000 miles from the comet. The 11,340 miles substends a 
>angle of about 0.47 arc minutes. It would seem this should be able to be 
>visually seen, and if not that, the increase in brightness from this 
>area should be able to be seen photometrically for sure. Just my own 
>guesses.
>Stan
>
>ketelsen@xxxxxxxxxxxxxx wrote:
>
>  
>
>>Jeff-
>>Do you have an estimate of how fast it may/will brighten?  It certainly
>>won't stay above our horizon for very long...  Just wondering if an
>>increase in brightness will take minutes or hours.
>>
>>-Dean
>>--
>>See message header for info on list archives or unsubscribing, and please 
>>send personal replies to the author, not the list.
>>
>>
>>
>> 
>>
>>    
>>
>
>--
>See message header for info on list archives or unsubscribing, and please 
>send personal replies to the author, not the list.
>
>
>
>  
>

--
See message header for info on list archives or unsubscribing, and please 
send personal replies to the author, not the list.

Other related posts: