Wednesday, August 31, 2005

Star event coming up

A great tip for all lovers of the natural world, just in case the sky clears:

by Steve Beyer — long-time Hayden Instructor;
author of "The Star Guide"; and
Adjunct Professor of astronomy at
the College of Staten Island, CUNY

Now through mid-September, plan to enjoy cosmic jewels, Venus and
Jupiter in conjunction. Brightest celestial objects after the Sun
and Moon, they present a spectacular sight side by side in the early
evening sky.

Shortly before sundown, if the sky is clear, go to a spot with a good
view of the western horizon. As sky colors fade and dusk deepens,
soon Venus, then Jupiter will appear in the west-southwest, a slight
left turn of your head from where the Sun touched the horizon. You
might remember and savor detailed telescopic and spacecraft pictures
of Jupiter and Venus, but to unaided eyes both planets look like
bright, beautiful stars that don't twinkle.

If clear skies cooperate, day by day, you can watch both planets
appear to move closer together until their minimum separation on
Thursday September 1. Then, Venus and Jupiter will seem to span
about the width of your index finger extended at arm's length. After
that date, the division increases, with Venus moving to the east
(left) of Jupiter. On the evenings of September 6 and 7, the
crescent Moon joins in to add even more magnificence to the vista.

Although these objects appear to line up as seen from our
perspective, they are really far apart in linear distances. On
September 1, distances from Earth are these: the Moon, about a
quarter of a million miles; Venus, 105 million miles; Jupiter, 576
million miles. For rough comparisons of relative distances, if the
Moon was as far from your eyes as the tip of your nose, Venus would
be a bit farther than first base is from home plate on a baseball
field, and Jupiter would be at a distance about twice the length of a
football field.

After enjoying the aesthetics of simply looking up at the evening sky
to see Jupiter and Venus moving along their orbits, check out close-
up views of these planets at web sites including those of NASA and JPL.

Clear skies!