Heads up for five-planet lineup

4/16/02 7:49:02 AM Pacific Daylight Time

Heads up for five-planet lineup

April 11, 2002 Posted: 8:20 PM EDT (0020 GMT)

(CNN) -- Round up the kids and the neighbors any time after
dusk Wednesday night, April 17th. The western skies will
provide a show that can't be matched by television or the
movies. And Mother Nature won't be doing a rerun for

Kelly Beatty, executive editor of Sky & Telescope Magazine,
talked with CNN producer Marsha Walton about the unusual
planetary alignment that will be visible all over the world
for the next four to six weeks.

WALTON: What causes this configuration of planets in our
solar system?

BEATTY: The planets operate like a clockwork as they go
around the sun, and sometimes they gather together. This is
one of those times. Every 20 years or so, Jupiter and Saturn
are close together in the sky, and everything else sort of
piles up around them. Jupiter and Saturn are in the evening
sky. They're very bright, they're very easy to see, and
they're being joined by the other "naked eye" planets --
Mercury, Venus, and Mars -- along with the moon this coming

WALTON: Do you need any special knowledge or any equipment
to take advantage of this spectacle?

BEATTY: This is the most basic kind of astronomy; it's what
we call doorstep astronomy. All you really need to do is go
someplace where you can see where the sun sets in the west.
Keep an eye on that spot as it gets dark. You'll gradually
see these planets appear. They'll look like stars but
they're not -- they're planets. What's arresting about this
view is they all line up in a straight line, starting down
very close to the horizon with Mercury and stretching up in
a straight line, most of the way overhead to the bright
planet Jupiter. On the night of April 17th, they'll all be
about equally spaced apart, the moon included.

WALTON: So there's no easy way to tell the stars and planets

BEATTY: You really can't tell the planets and stars apart.
To the ancient Greeks, these were known as wanderers, and
the word "planet" derived from the Greek word for
"wanderer," so they're "wandering stars." We only know that
they're planets because they kind of mingle around the
background stars. They move from night to night. And in
fact, that's one of the beautiful things about what's going
on right now, as you watch these planets from night to night
you'll see that their positions change. They're kind of
doing a dance with one another as they circle around the

WALTON: When is the next time there will be such a clear
lineup of these planets?

BEATTY: The next time we'll have a chance to see anything
like this, anything nearly like this will be in the year
2040. That's the next time they'll all be clumped together
in the evening sky. A lot of us won't be around then, so I
think we should take advantage of this while we can!

WALTON: Where and when should we be looking up?

BEATTY: We're keying on April 17. That's when an eerie
straight line alignment takes place. But there will be other
nights when there will be interesting things to watch. For
example, later in the month, Mercury will be jumping its
highest in the sky; you'll be able to see it down low near
Venus. On May 5, Venus, Mars and Saturn will form a kind of
triangle in the sky.

I'd suggest people make note of where the sun is setting,
and then go out another 45 minutes later and look in the
same general direction. By then, the sky will be dark
enough, the brightest stars will be out, these planets will
be out. In this particular alignment, Mars will be the
faintest and the hardest to see. Mercury will also be hard
to see only because it's down very close to the horizon, so
you need a place where it's very clear all the way to the

WALTON: Will big city lights make it harder to see this?

BEATTY: Even people who live in the city can enjoy this.
Despite all the light pollution that you have to deal with,
planets are one of the last things to be blotted out of the
sky. So you'll be able to see this no matter where you are
-- urban, rural, remote locations -- everyone will get a
chance at this one. You should take advantage of it!