Subject: (urth) Diameter of the Old Sun

From: Michael Andre-Driussi <mantis at siriusfiction.com>
Date: Mon, 04 Mar 2002 00:17:51 +0000

Assuming that Lune Diameter = 2160 miles, and Orbit = 150,000 miles . . .

And using formula S = 57.3 * D/R

Shows us that the angular diameter (i.e., size in sky from Urth) of Lune is
0.82 degrees (compared with Moon from Earth as 0.52 degrees--bigger, but
not quite doubled in size).

Supposing that the Old Sun is swollen (Supposition 1); further supposing
that Lune can eclipse the Old Sun (Supposition 2); this implies that the
angular diameter of Old Sun is around 0.82 degrees (compared to Sun's 0.53
degrees).  What is the diameter of Old Sun?

0.82 = 57.3 * x/92.960 million miles
76.2272 = 57.3 * x
1.3303 = x = 1.33 million miles

According to these figurings, Old Sun has a diameter of 1.33 million miles
(2.14 million km), which translates into 0.014 AU.

If the above is correct, then there is little hazard of the planet we call
Mercury being engulfed by the swollen star, since Mercury orbits at 0.38 AU.

=mantis=

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