Thursday, December 2, 2010

How to Catch Space Dust in the Snow (from MacBeth's Opinion)

Every day, the earth gathers 100 tons of dust from space!  You can easily catch an observe some of this minute invasion force, using simple household items--a coffee filter, oven, and a microscope (a magnifying glass may do, as space dust is fairly large), and a magnet.  Since much of space dust is made up of iron, it is very magnetic!  Even if you don't find space dust, you may be surprised by the amount of regular old dust in snow--even fresh clean snow!
Take a bit of fresh snow and place it on a coffee filter inside a cup (cone filters work best).  Allow the snow to melt away, and let the filter dry (you may use a warm oven to aid this process).  Examine any dust left behind.
How much is there?  Can you see any large "dust?"  Use a magnifying glass of a microscope to examine the specks.  Space dust is roughly spherical, having melted on its journey through the atmosphere.  Sometimes, space dust has a tiny "tail."  Sometimes, especially if the dust contains nickel, it looks like Mickey Mouse--a tiny sphere with "ears."  Use a magnet on the dust to determine if it contains iron.
Older students may wish to quantify the observation, by weighing the dust collected (use a fine, digital scale, available from Science Kit).  Even earth dust is heavy, and while snow is naturally dusty, sitting snow will have an increased volume of dust.  How much more concentrated does the dust sample become in one-day-old, two-day-old or week old snow?   Cover some snow to protect it from gathering "new" dust.  Does the volume of dust increase as the volume of snow decreases?  Why?

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