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Sunspots Essay Research Paper Our Sun continuously

Sunspots Essay, Research Paper

Our Sun continuously converts hydrogen into helium and with this process it

provides the essentials for life processes. In doing this it controls “our climate,

provides light, raises tides, and drives the food chain” (Schaefer 34). Our Sun

also has influenced many beliefs now and in the past. History has documented

Sun worshipping religions while many current societies use solar calendars

(Schaefer 34).

Because the Sun is so influential, imperfections of the Sun, such as

sunspots will continue to impact life on Earth. The discovery of sunspots is

correlated with the invention of the telescope in 1608, although there are earlier

recordings of sunspot like activity from China (Schaefer 35). Galileo was one of

the astronomers who decided to publish his findings and use sunspots in one of

his theories of Chief World Systems (Schaefer 35-6).

Today many patterns including real estate sales to fluctuations in the

climate have been attributed to the cycle of sunspots. These fluctuations may be

an explanation of the decline of Sun worship in India due the increased sunspot

activity during the time of the Medieval Maximum. Throughtout history these

fluctuations have been omens (e.g. a slave revolutionists incited a riot when he

interpreted the site of a large black area on the Sun as the black taking over the

white) (Schaefer 38). There are also modern examples of solar fluctuations

affecting the Earth like the delayed launch of the Hubble Telescope (Schaefer

38) and the disruptions in electrical and radio technology during solar flares due

to increased activity of sunspots at the last solar maximum in 1989.

Sunspots are the most apparent features on the Sun’s surface or

photosphere. Anyone could use a filter such as a welder’s helmet to observe

groups of sunspots. A sunspot consists of two regions, the umbra and the

penumbra. The temperature of the umbra can be as low as 4,000 K and the

penumbra that surrounds the umbra has a temperature of about 5,500 K which

contrasts to the photospheric temperature of 6,000 K. The difference in

temperatures makes the sunspots appear dark against the brightness of the

photosphere (Nicolson 123).

A sunspot’s average size is comparable with the Earth. They form in

regions of concentrated magnetic fields. These fields hamper the flow of energy

to the affected area. The magnetic fields on the Sun are detected by the

Zeeman effect, which shows a single spectral line that splits if a magnetic field is

present (Nicolson 124). In each sunspot pair in the northern hemisphere the first

spot has a north magnetic polarity and the second has a south magnetic polarity

{figure 1}, while in the southern hemisphere it is the opposite pattern. In sunspot

groups the polarity of the sunspots gets increasingly complex (Nicolson 124).

The sunspots follow a cycle of eleven years. The number of sunspots

varies monthly from zero to the hundreds. During the eleven year cycle there are

periods called solar maximum and solar minimum where the number of sunspots

reaches its peak or low. At the time of solar max the Sun’s magnetic poles

reverse. The north magnetic pole switches to extend through the southern

hemisphere and the south magnetic pole extends through the northern

hemisphere. In fact the Sun reached its solar max in February of this year

(Philips 1).

According to astrophysicist, K. V. K. Nehru the magnetic poles reverse

because of a theory of high range temperature matter. His theory states that

one way high temperature matter acts in is thredules, which is “[m]atter in the

ultra high temperature range manifests as slender, unidirectional, expanding

threads that keep forming and dissolving” (1Nehru 8). Nehru states that

co-magnetic lines follow the thredules as they expand. North and south

thredules form two “sheaves” one north polarized and one south polarized, but

where the sheaves interact opposite polarities are adjacent to each other {figure

2}. The thredules cannot expand beyond the high temperature core, however

the magnetic fields lengthen out into space. When the magnetic lines reach into

space the opposite polarity extending out from the opposite side attract each

other and form loops. Over time this attraction leads to the angle of where the

magnetic field extends from is altered from the high latitudes to lower latitudes

until the polarities flip (2Nehru 1-3).

This theory explains how the magnetic poles of the Sun reverse

and it also answers another question about the nature of sunspots. When the

sun begins it cycle of sunspots the majority of the sunspots are at the higher

latitudes while later in the cycle they appear at the lower latitudes. This

resembles the pattern of where the magnetic fields extending from the thredules

are positioned.

The National Center of Atmospheric Research is using sunspots to try to

predict the damage the Sun radiation is causing to the Earth’s atmosphere. To

do this they measure the amounts of radiation fluctuations. Utilizing that

information they can estimate the amount of radiation that reaches Earth. Their

results will assist astronomers and other scientist in understanding radiation’s

effect on the atmosphere (Analyzing 11-12).

Another project called Ulysses is currently being used to study the Sun.

The probe Ulysses was “launched in 1990 to observe the solar system from very

high solar latitudes” (Philips 2). Ulysses is the first probe to ever observe from

such latitudes. Ulysses has just finished flying under the Sun’s south pole and in

the fall it will be flying of the north pole at a solar latitude of 2.2 AUs (Philips 2).

This project will hopefully enable scientists to learn more about sunspots and

other properties of the Sun.

Understanding more about sunspots, their cycle, radiation, and magnetic

properties will facilitate scientists to unlock the mysterious workings of the Sun.

With today’s technology this understanding will come more quickly. Knowledge

of sunspots may lead us to be able to predict when solar activity could affect the

Earth like it did during the solar max in 1989. Information like this could

eventually allow us to be able to protect ourselves from solar radiation.

“Analyzing Variation in the Sun’s Radiation”. USA Today. 26 2637 (1998) :

11-12.

Nehru, K.V.K. Glimpses Into the Structure of the Sun—Part 1 The Nature of

Stellar Matter. March 22, 2001. .

Nehru, K.V.K. Glimpses Into the Structure of the Sun—Part 2 The Solar Interior

and the Sunspot. March 22, 2001.

Nicolson, Iain. Unfolding Our Universe. New York: Cambridge University Press,

1999. 123-4; 276+

Philips, Tony Dr. “The Sun Does a Flip.” SpaceScience. Feb. 15, 2001. March

19, 2001. .

Schaefer, Bradley E. “Sunspots that changed the World.” Sky & Telescope. 93.4

(1997). 34-38.




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