Solar Storms and You!

Activity 9: A Soda Bottle Magnetometer....Data

Data taken between February 1-5, 1999 at NASA, Goddard Space Flight Center with the Mark 2 magnetometer by Dr. Sten Odenwald.

Solar conditions during this time:
2-1-99   Quiet
2-2-99   Quiet
2-3-99   Quiet
2-4-99   Quiet
2-5-99   Quiet
Note, the Quiet/Disturbed/Active index used at the 
Space 
Weather site is 
rather crude. In several instances a 'Quiet' condition was posted even though 
the 'Current View' image of the Earth from space by the POLAR satellite clearly showed the 
ring-shaped oval of auroral activity in progress over Alaska and Canada. In 
the next data runs I will indicate both the posted condition, and the strength 
of the  'auroral oval'  on a scale  B=Bright, W=weak and A=absent.


Data:

2-1-99
9:00      5.5
9:45      5.5
11:20     4.5
12:20     4.5
12:40     4.0
14:10     4.5
14:55     4.0
15:50     4.0
16:15     4.0

2-2-99
9:00      5.5
9:35      5.0
10:00     5.5
10:25     5.0
10:45     4.0
11:00     4.0
11:40     3.5
12:05     3.5
13:00     4.0
13:15     4.5
13:55     4.0

2-3-99
9:45       5.5 oscillating spot
10:20      6.0 steady spot with amplitude of swing less than 0.2 centimeters
11:20      7.0 s
11:35      7.0 s
12:20      6.5 s
12:30      6.5 o
13:00      6.0 o
13:30      5.5 o
14:00      5.0 o
14:40      6.0 o
15:05      5.5 o
15:20      5.0 o
15:30      5.0 o
15:40      5.5 o
16:05      5.0 s
16:20      5.0 o
16:50      5.0 s
17:10      5.5 s

2-4-99
9:00       6.0 s
10:00      5.5 s
10:50      5.5 s
11:10      5.0 s
11:20      4.5 s
12:20      3.0 s
12:35      3.0 s
12:40      2.5 s
12:50      2.0 s
13:00      2.0 s
13:20      1.0 s
13:30      1.0 s
13:40      0.0 s
13:50      0.0 o    big swings, 0.5 cm amplitude
14:20      1.0 o
14:40      0.0 s
14:50      0.5 o
14:55      0.5 s
15:15      0.5 s
15:40      0.0 s    Lightning!
15:50      0.5 s
16:15      0.5 s
16:25      7.0 o    3 cm amplitude
16:30      6.0 o    6 cm amplitude
16:35      6.0 o    1 cm amplitude
16:45      6.0 o    2 cm amplitude
16:50      6.0 o    6 cm amplitude
16:55      6.0 o    4 cm amplitude
17:00      7.0 o    1 cm amplitude
17:05      6.0 o    5 cm amplitude
17:15      6.0 s    0.5 cm amplitude
17:20      0.0 o    1 cm amplitude

2-5-99
9:00       8.0 s    spot 'stuck' at -2.0 cm so I shifted it back to 8.0 cm
9:20       7.0 s
9:35       7.0 s
10:05      6.0 s
10:30      6.0 s
11:10      5.0 s
11:45      4.5 s
12:00      4.0 s
13:05      3.0 o
14:10      8.0 o   3 cm amplitude
14:25      2.0 s
15:00      2.0 s   0.5 cm amplitude or less
15:25      2.0 s
15:40      1.0 s
16:10      1.0 s
16:45      1.0 s

This completes the second consecutive week of observations. According to the Space Weather reports, the sun was quiet during this time. I have decided to include, in addition to the spot position, a measure of the amplitude of the spot oscillation. Usually, the spot is 'stable' with either no discernible oscillations going on or only a weak 0.5 cm peak-to-peak amplitude of its normal 4-second swinging. The measured value when it is swinging is the average value between the maximum positive and negative ends of its swing. Sometimes, however, the spot becomes very active as for 2-4-99, and sporadically on 2-3-99 and 2-5-99.

At least in the case of the afternoon data taken on 2-4-99 there was a very good reason for this activity. A storm front passed through the Washington DC region, especially in the county where Goddard is located. The approaching electrical disturbances could be detected by this magnetometer beginning with the 11:20 data when the spot position shifted from its apparently normal 5.0 - 6.0 location, to 4.5 cm. It continued to slide from 4.5 to 2.0 by 13:00 and then to 0.5 by 16:15 with little oscillation along the way. Then at 16:25 oscillations with large amplitudes began, and persisted until 17:15. The next morning at 9:00, the spot had shifted to -2.0 cm and so, with no further atmospheric disturbances outside, I decided to shift the scale back to 8.0 and begin the new series of measurements. 2-5-99 repeated the pattern of 2-4-99 with a steady erosion of the spot position from 8.0 to 1.0, but there were only two instances of oscillations around 13:00-14:00. There was no apparent meteorological cause for the 14:10 oscillation. This demonstrates that:

1) you need to keep watch on you local AND regional weather reports because this magnetometer can detect approaching electrical activity in lightning by up to 4 hours.

Also, 2) the amplitude of the oscillation is another parameter that you should try to keep track of, not just the average spot position on your measuring scale. The average position tracks the gradual changes in the local electromagnetic field, but the oscillations measure the strength of the rapid changes in this field which are causing the excitation of the natural 4-second oscillation of the mirror/magnet pendulum just as we saw in the December data when there were passing cars on the roadway outside.