Re: New member talk
Jim Varney (jamesv@softcom.net)
Tue, 26 May 1998 22:31:33 -0700
On 26 May 98, Terry Pundiak wrote:
> Do you have any simple formulas for calculating sat's fractinal
> illuminations out there so I could use the values in Molczen's tle's?
Welcome to the list.
phase = 0.5(1 + cos(d)) where d = phase angle (sun-sat-observer angle)
and phase will range from 0 ("new") to 1 ("full").
> ... and maybe formulas for the tracking from original tle? --- I don't
> mind trying to do this on a Mac just for the fun of it, but is is
> probably too large a project - anything to avoid the obvious (buy a pc).
http://www.celestrak.com/NORAD/documentation/index.html
has a NORAD document called "Spacetrack No. 3" that includes FORTRAN source
code for several propagators. You probably couldn't do it with Hypercard;
you'll need a FORTRAN compiler or use another language and translate.
> I'd also like any recommendations observers have for binocs... now, I
> realize that the ones I have are poor... are 11 by 70 mm by Orion a good
> buy? (I don't want to spend more than they cost.) or any thing real good
> in the 7 by 50 format?
You're in Pennsylvania! Take advantage of an astronomy dealer in your
state known for friendly service and low prices: Pocono Mountain Optics.
http://www.rahul.net/resource/regular/products/pocono/pg1.htm
Generally the Orion line of optics has a mixed reputation so you'd better
try them out first to see how you like them. Fujinons are very good.
-- Jim
__________________________________________________________
Jim Varney
Member, Sacramento Valley Astronomical Society
Sacramento Iridiums www.softcom.net/users/jamesv/index.htm