BOULDER, Colo. -- Wow! Fall just started and I've already been out to cover my first mountain snow storm (of course, we didn't get as much snow last week as we expected, but I'm sure there's still plenty more coming later this year).

Despite my fixation on the changing seasons, I covered another story this week that I wanted to expound on here in the blog. On Tuesday, I went to the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado in Boulder. We covered the MESSENGER flyby of Mercury and got to talk with the scientist who developed one of the instruments on the spacecraft.

First, let me just say that I'm pretty jealous of the students at CU who get to work first hand with these space missions. They actually get to communicate with and control several satellites at the LASP operation control center. MESSENGER is not actually controlled at LASP, but one of the scientists, Bill McClintock, developed a vital instrument on MESSENGER.

The instrument is called the Mercury Atmospheric and Surface Composition Spectrometer, or MASCS. Bill explained it as "an instrument that measures reflected light from the surface of the planet. We analyze the color of that light, and it tells us something about the composition of the surface."

He showed us a copy of the casing for the MASCS. It is the size of a bread box and was amazingly light because it was made from magnesium. He said all of the instruments on MESSENGER had to be extremely light-weight in order for the spacecraft to have enough fuel to make it to Mercury. The casing he showed us was originally supposed to make it on the spacecraft, but it got damaged so they had to make a new one. Now it serves as a good show-and-tell piece!

One of the most interesting things I learned was that MESSENGER launched in 2004, but still isn't in orbit around Mercury. McClintock said NASA has to fly MESSENGER around the sun 15 times and use the sun's gravity to slow it down. Then, it can finally catch up with Mercury in 2011 to begin its one-year orbit of the planet.

After that one year, MESSENGER will be out of fuel and will just crash into Mercury's surface. That's quite a way to go out! NASA has already taken some great pictures of Mercury, but McClintock said he and other scientists can't wait until it begins orbiting the planet. He said trying to digest all of the data MESSENGER will send back will be like trying to drink from a fire hose!

A Peek at the Planets:

If you plan to search for planets at dusk, Jupiter will be ascending slowly in the SE to SSE through October. Neptune will be very faint, but you can also spot it near Jupiter. The best time to see the planets this month will be at dawn. Mars will rise in the ENE six hours after sunset and climb very high in the SE to S by dawn. Venus, Mercury and Saturn will all be visible before sunrise in the E. The most striking planet gatherings will be about one hour before sunrise on Oct. 8th and 13th when Venus, Mercury and Saturn are all close together.

The Moon in Motion:

Full Moon: Sunday, October 4
Last Quarter: Sunday, October 11
New Moon: Sunday, October 18
First Quarter: Monday, October 26

This month's full moon is known as the Harvest Moon because it is the closest full moon to the fall equinox.

From the History Books:

A female U.S. astronaut made an important achievement 25 years ago. It happened in October 1984 when the Space Shuttle “Challenger” was on an 8 day mission. During the mission, Kathryn Sullivan became the first U.S. woman to walk in space. The flight was also the first to include two women astronauts, Sally K. Ride and Kathryn Sullivan.