The Pluto fly-by

One of the difficulties in writing a column such as this is something called "lead time." That is the amount of time before the publication date the copy has to be into the newspaper. In this case, the copy must be sent in at least by the Friday before the Wednesday publication.

I will say that I have not always met that deadline, however, the newspapers have been most kind in their allowing me some leeway, for which I am thankful.

That is the reason I am not able to bring to you -- the reader -- any significant news about the planet Pluto from the New Horizon mission; I am writing this well before the July 14, fly-by, so we will just need to wait.

Our knowledge about Pluto is very scant. We know about as much about it as we did about Mars before robotic missions were sent there to not only orbit but land on the surface. So whatever we receive will be a giant leap forward.

What we do know is that Pluto is about two-thirds the diameter of our moon, and up until a few years ago we only knew of the one moon, Charon (pronounced Shehr-on). Now we know there are five (at least). There is also the possibility that there are rings. Not as glamorous or as large as Saturn's rings, but rings none the less.

There are some who believe that the Pluto/Charon pair are really a double planet since Charon does not really orbit Pluto as much as they swing around a common center of gravity called a "barycenter" because that center is outside of Pluto's mass.

If Pluto and Charon were put side by side, they would extend almost across the width of the United States.

So, here we sit, waiting for July 14, so we can see something we have never seen before, or at least get a much better view than the cloudy, fuzzy images that earth-bound telescopes -- even the Hubble Space Telescope -- have been able to render.

If you would like to watch in real time as New Horizons passes Pluto you will need to be up early as the space probe will arrive at 05:50 am MDT. Point your favorite web browser to: www.slooh.com; or www.nasa.gov/newhorizons; or http://pluto.jhuapl.edu.

Just be aware, those sites will probably be swarmed and you may have trouble getting on, so plan on showing up early.

SKY WATCH: New moon today. Remember, at new moon, no moon is visible. It is between Earth and the Sun. A good time to restart your monthly moon watch as it changes form . A slender sliver of the moon will show up near the Venus/Jupiter pair on the evening of Saturday, July 18. The other bright point of light just above them is the star Regulus, the brightest star in Leo, the Lion. Start looking for them starting about a half-hour after local sunset, they will all be very close to the western horizon. Saturn is almost directly south about halfway up the sky just above the head of Scorpius. Even though you won't be able to see it, find the "Tea Pot" shape of Sagittarius just left of Scorpius. On the left side is a small asterism called "The Teaspoon." Pluto will be just above it. Just so you will know.

NEXT WEEK: Starting our summer constellation tour, and more astronomical blathering.