[AZ-Observing] Re: Mars Alert

> Space Weather News for Oct. 18, 2005
> http://spaceweather.com
> looks like a brilliant orange star.  If you're impressed by Mars 
> tonight, you'll be even more impressed two weeks from now when Mars 
> makes its closest approach to Earth for the next 13 years.


Actually, it won't be *that* much more impressive two weeks from now, when it 
will have brightened from its current magnitude -2.07 to -2.27.  And it will be 
brighter still a week after closest approach on the night of opposition, when 
it will be magnitude -2.33.

In the "more info than you need" department, here's a table showing the 
brightness and angular size, as well as the distance from the earth and sun in 
a.u., and illuminated fraction.  October 31 is closest approach to earth, and 
November 7 is opposition.


Date    Mag.   Size(")  Delta    r    %Illum
                       
10/19  -2.07    19.75   0.474  1.438    97.7
10/31  -2.27    20.18   0.464  1.452    99.6
11/7   -2.33    19.95   0.470  1.461   100.0


I'm not sure that I get why it's brighter on November 7 than October 31.  It's 
farther from both the earth and the sun, but I think it has something to do 
with being in a nearly perfectly Full phase.

Tom

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

Other related posts: