Wednesday, June 6, 2012

Last Day of A and the Transit of Venus

A is for Address.
Sign for A
 Address mix up:My kids still struggle with our address. So I took a few sheets of paper and folded it 3 times. It created card like separation.I wrote each letter and number of our Address and cut out the cards and mixed it up.Then I showed them our address and had them put the cards in the right order.


The number of the week is 1.The kids practiced writing A's and number 1's.I had Lex count as far as she could with the blue counters.They had some impromptu fun with them when I put the Tot down for a nap.


1rst grade review: We talked about the ai and ay sound.If two vowels are together it makes it say it's name. I had him do a worksheet I found at

For the au and aw words I made a go fish game with different words.I am not sure how to put it in pdf form so that you all can down load it.It took me a while and it reminds him of the words.Words like astronaut,awful,pause,and we learned a new vocabulary word brawn.

We went to a fun puppet show at  the library.

It has been a busy day topped off with watching the transit of Venus across the sun.
I found this awesome web site that explains this on a paper plate I thought it was so clever. Here is the link : is only some of it here on my blog.

Paper Plate Education"Serving the Universe on a Paper Plate"

Activity: Transit Frequency

inclined.jpg (23247 bytes) 
A rare transit of Venus occurred June 8, 2004, when Venus passed directly between the earth and the sun.  Though it seems like that phenomenon should happen frequently, transits come in pairs that are eight years apart, followed alternately by spans of 121 ½ years and 105 ½ years.  In the 21st century, the transit pair occurs June 8, 2004, and June 5-6, 2012.  This activity offers a simplified explanation of that seemingly irregular period.

The Race

Imagine that daughter Venus and her mother Earth are going to race around their house.  The young daughter, faster of the two, will run close to the house, while Mom will encircle the whole yard further out.  Mother Earth agrees to run eight laps or until daughter Venus overtakes her five times, whichever comes first.  As seen from above, they run anti-clockwise (i.e., "planetwise").
They line up just slightly forward (to the right) of the yellow front door to start the race.  This alignment is called an inferior conjunction--Venus is between the sunny door and earth.  
"On your mark...get set...GO!"
In our race, mother Earth goes around once in a minute, but daughter Venus does it in less than 37 seconds, or about 8/13ths of Mom's time.   (Planet Venus orbits the sun in 225 days; planet earth orbits the sun in 365 days.  Dividing 225 by 365 equals 8/13.)
After running only 1.6 laps (around the house once and just past the back of the house a second time), mother Earth sees daughter Venus overtake her.  At that moment, Mom has completed 1.6 laps while daughter has completed 2.6 laps.  
Mom notes her and daughter Venus' positions.
The race continues.  Each time mother Earth completes another 1.6 laps, daughter Venus catches up to and overtakes her on the inside track.  Finally, after mother Earth has completed eight laps around the house, daughter Venus catches up to Mom for the fifth time.  Conveniently, the finish line coincides with the original starting line by the yellow front door of the house.
Mom's eight laps are shown on the outside of the plate at left.  Five times (shown in five colors) she ran 1.6 trips around the house; five times daughter caught up and overtook her again.  Daughter's corresponding position at those five meetings is shown in the same color.   During mom's 8 laps, daughter sprinted 13 times around the house.  For clarity, daughter's 13 laps are not shown. 
It would seem daughter Venus passes between mother Earth and the yellow front door (ignoring the intervening house) five times in eight years.  Yet transits do not happen every 1.6 years, because two major factors interfere.  First, daughter and mother are not running on a level surface.   Second, instead of running a clean 8 thirteenths of mother Earth's speed, daughter completes one lap closer to 7.997 thirteenths of mother Earth's speed.  

On the paper plate, cut two slits just outside the Venus markings to incline the planet's orbit. 

Contributed by Chuck Bueter

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