Jimmy Westlake: Don’t miss the double evening star   Jimmy
Westlake  Jimmy Westlake's Celestial News column appears
Tuesdays in the Steamboat Today.  Find more columns by Westlake
here.  The solar system’s two innermost planets, Mercury and
Venus, behave differently than the rest of the planets. Instead
of being free to wander all the way around the night sky, they
are tethered to the sun so that they seem to swing back and
forth, from one side of the sun to the other. Consequently, each
planet spends a brief time as our “evening star,” visible right
after sunset, followed by a brief engagement as our “morning
star,” visible just before sunrise.  The best time to spy each
planet is when it is near its greatest angular distance from the
sun, an event called greatest elongation. Even at greatest
elongation, Mercury never can be seen more than 28 degrees from
the sun. That’s not much more than the width of your
outstretched hand held at arm’s length. Venus, because of it’s
larger orbit, fares a little better — i